Scottish Marine Special Protection Area Network Assessment: Species Assessments

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Scottish marine Special Protection Area network assessment: Species Assessments

September 2018

Scottish MPA Programme Scottish SPA Network Assessment

Species Assessments (all species)

Document version control

Version* Date Author Reason / Comments 1st drafts Febuary/ Kate Thompson, First drafts completed using standard species March 2018 Helen Wade & template agreed at Workshop 1 assessments Emma Philip (20/12/2017) 2nd drafts March 2018 Kate Thompson & Second drafts to address species Emma Philip recommendations from Workshop 2 assessments (26/02/2018) 3rd drafts April 2018 Kate Thompson & Final drafts species Emma Philip assessments All species May 2018 Emma Philip Merged all species assessments assessments – 1st draft All species July 2018 Gail Churchill Quality Assured (QA) assessments – 2nd draft All species August Kate Thompson Amendments further to QA assessments 2018 – 3rd draft All species September Liz Scott & Kate Final formating all species assessments 2018 Thompson assessments – 4th draft All species September Kate Thompson & Final version for publication assessments 2018 Emma Philip – Final draft *Individual version controls are available for each species assessment

Distribution list

Format Version Issue date Issued to Electronic 1st drafts (Arctic tern, February Workshop 2: Bob Furness, Greg Slavonian grebe, red- 2018 Mudge, Kate Thompson, Emma breasted merganser and Philip & Helen Wade (SNH), Jared razorbill) Wilson (MSS) and Kerstin Kober & Matt Parsons (JNCC) Electronic 2nd drafts (12 species- March Advisory Panel: Greg Mudge & seasons reviewed by 2018 Emma Philip (SNH), Jared Wilson panel**) (MSS) and Matt Parsons (JNCC) Electronic All species assessments – July 2018 Gail Churchhill 1st draft Electronic All species assessments – August Emma Philip & Kate Thompson 2nd draft 2018 Electronic All species assessments – August Liz Scott 3rd draft 2018 Electronic All species assessments – September Emma Philip & Kate Thompson 4th draft 2018 **See main report

Contents

Introduction 1

Arctic skua (breeding) 2

Arctic tern (breeding) 9

Atlantic puffin (breeding) 15

Atlantic puffin (non-breeding) 23

Black-headed gull (non-breeding) 28

Black-legged kittiwake (breeding) 35

Black-legged kittiwake (non-breeding) 42

Black-throated diver (non-breeding) 48

Common eider – faeroeensis subspecies (non-breeding) 54

Common eider – mollissima subspecies (non-breeding) 61

Common goldeneye (non-breeding) 70

Common guillemot (breeding) 76

Common guillemot (non-breeding) 84

Common gull (non-breeding) 92

Common scoter (non-breeding) 98

Common tern (breeding) 106

European shag (breeding) 112

European shag (non-breeding) 120

European storm-petrel (breeding) 128

Goosander (non-breeding) 134

Great black-backed gull (breeding) 140

Great black-backed gull (non-breeding) 146

Great cormorant (breeding) 152

Great cormorant (non-breeding) 156

Great crested grebe (non-breeding) 161

Great northern diver (non-breeding) 166

Great skua (breeding) 174

Great skua (non-breeding) 181

Greater scaup (non-breeding) 188

Herring gull (breeding) 194

Herring gull (non-breeding) 201

Leach's storm-petrel (breeding) 209

Lesser black-backed gull (breeding) 213

Lesser black-backed gull (non-breeding) 218

Little auk (non-breeding) 224

Little gull (non-breeding) 228

Little tern (breeding) 234

Long-tailed duck (non-breeding) 241

Manx shearwater (breeding) 249

Northern fulmar (breeding) 256

Northern fulmar (non-breeding) 264

Northern gannet (breeding) 271

Northern gannet (non-breeding) 278

Razorbill (breeding) 282

Razorbill (non-breeding) 288

Red-breasted merganser (non-breeding) 294

Red-throated diver (breeding) 302

Red-throated diver (non-breeding) 310

Roseate tern (breeding) 317

Sandwich tern (breeding) 321

Slavonian grebe (non-breeding) 327

Sooty shearwater (non-breeding) 333

Velvet scoter (non-breeding) 338

Introduction

This document comprises a series of 531 species-season assessments for 39 species of marine birds, 38 of which occur regularly in Scottish waters2. These species assessments have been prepared by Scottish Natural Heritage in support of the ‘Scottish proposed Special Protection Areas Network Assessment’ commissioned by Marine Scotland covering 15 marine proposed Special Protection Areas (pSPAs) that were the subject of public consultation in 2016/17.

The first step in the network assessment was the preparation of the following assessments. For each species-season, these assessments provide an objective indication based as far as possible on published sources of data, of the relative value that protected areas in Scotland’s marine environment could make to that species’ conservation in Europe and provide an indication of what is considered to be appropriate in terms of level of representation in marine SPAs. This is then compared with the number and location of proposed marine SPAs for each species. These species assessments should be read in conjunction with the Network Assessment.

Content of species assessments

Table 1 in the species assessments considers a standard set of species conservation status attributes encompassing: GB marine distribution; the relative importance of Scotland; contribution to relevant biogeographic populations; and European population conservation status. These attributes are described in detail in section 5.1.1 of the network assessment. The associated thresholds and scoring system (detailed in Annex 2 of the network assessment) enable the ‘relative value’ (Very High, High, Medium, Low or Very Low) of protected areas in Scotland’s marine environment to the conservation of each species in Europe to be objectively assessed.

Section 5.1.2 of the network assessment details the scaled approach to describing a minimum level of network representation expected for each species based on the ‘relative value’ score; essentially, the higher the relative value the higher the expected number of SPAs where the species is represented.

Table 2 in the species assessments considers vulnerability to anthropogenic threats and pressures and associated potential value of additional replication within the marine SPA network (see section 5.2.2 in the network assessment).

Table 3 in the species assessments considers the occurrence of each species-season within each proposed SPA where it is a qualifying feature. As described in section 5.2 of the Network Assessment, this includes consideration of populations represented, replication across the network and within OSPAR regions, geographic range and linkages among SPAs.

In the Summary in each species assessments, the minimum level of representation indicated by Table 1, together with any considerations for additional replication (including management of anthropogenic threats and pressures identified in Table 2), are compared within the actual number of proposed SPAs for each species-season (Table 3) This allows an assessment of whether the number of proposed SPAs for species-season is appropriate to the relative value of protected areas in Scotland’s marine environment to the conservation of the species in Europe and informs the final Conclusions in each account.

1 Including two subspecies of common eider Somateria mollissima mollissima and S. m. faeroeensis 2 Roseate tern (breeding) was also included as it previously bred at SPA colonies in Scotland

Arctic skua (breeding)

1. Introduction

Arctic skua is a regularly occurring migratory species. Breeding Arctic skua is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for Arctic skua (breeding)

2. Species account

Table 1 Summary of status of Arctic skua (breeding)

Species’ status Score Notes

GB marine Widespread Modelling of boat-based and aerial survey data indicates that in the summer months Arctic skua are distribution widely distributed in GB waters (JNCC range score 99.6%1) with highest density areas around the

northeast coast of Scotland and the Northern Isles, off the east coast of England north of The Wash, and several hundred kilometres west of the Outer Hebrides (Bradbury et al, 2017). The concentration of birds off the east coast of England is similar to that observed by Stone et al (1995) in the post- breeding period and is most likely associated with non-breeding or post-breeding birds. Significance of High Arctic skua breeding sites in GB are confined to coastal moorlands in proximity of other seabird Scotland’s seas colonies in the far north and west of Scotland, particularly in Shetland and Orkney, which in 1998- in GB context 2002 held 52% and 34% respectively of the Scottish (GB) population (Mitchell et al, 2004). Smaller colonies are found further west, including on Handa (Sutherland). There are few data on the foraging range of breeding Arctic skuas (Thaxter et al, 2012), but recent tracking studies at Fair Isle indicate that birds may currently be ranging up to 150km in search of food (Humphreys et al, 2017). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 2,136 pairs, equivalent to 6.1 to 13.9% of the biogeographic population (NE population Atlantic) estimated at 15,000 to 35,000 pairs (Mitchell et al, 2004). However, the GB population has declined markedly since 2002 (Foster & Marrs, 2012; Meek et al, 2001) such that its current contribution to the biogeographic population is unclear. Arctic skua breeding in northern Scotland are at the southern edge of the species’ range in the NE Atlantic.

Arctic skua have a high-latitude circumpolar breeding distribution, with the largest populations in Russia, Canada and Alaska and in the NE Atlantic they breed in Iceland, Norway, Greenland, Sweden, Finland, Faroes and Scotland (Mitchell et al, 2004). Arctic skua winter in the southern hemisphere (BirdLife International, 2018). European Least The European and global conservation status of this regularly occurring migratory species is Least population Concern Concern (Secure) (BirdLife International, 2017, 2018).

conservation status Species’ status summary and The European population status of breeding Arctic skua is considered Least Concern and GB is of assessment of level of Medium importance to the biogeographic population of this regularly occurring migratory species. representation in Scottish Arctic skua (breeding) have a widespread distribution in GB waters with highest densities largely off SPA network. Scotland, which holds 100% of the GB breeding population. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of Arctic skua (breeding) in Europe is Low.

This assessment indicates there is an expectation of Arctic skua (breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of Arctic skua (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have high or threats and medium impacts on relevant populations of Arctic skua (breeding) (Furness, 2016). In particular, Arctic skua are pressures vulnerable to reduced availability of fish such as sandeels (Furness & Tasker, 2000) to the other seabirds (auks, Arctic terns and kittiwake) from which Arctic skuas steal their prey. As well as directly affecting provisioning rates of Arctic skua chicks, sandeel availability underpins complex interactions with the larger great skua, which is a significant predator of Arctic skua chicks at some colonies (Dawson et al, 2011; Meek et al, 2011; Jones et al, 2008; Caldow & Furness, 2000; Phillips et al, 1996).

Arctic skua have been identified as being at risk of extinction as a breeding species in Britain as a consequence of climate change (Russell et al, 2015). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Arctic skua populations are vulnerable to high or medium impacts from a number of different threats and pressures. Replication within OSPAR regions should be considered.

3. Contribution to Scottish SPA network

This section considers the occurrence of Arctic skua (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Arctic skua (breeding) are being considered for inclusion at two marine proposed SPAs and are represented in seven existing colony SPAs, six of which have marine extensions classified to protect areas used by various cliff-nesting seabird species for maintenance behaviours, such as preening, loafing and roosting, close to the colony .

Table 3 Summary of occurrence of Arctic skua (breeding) within marine proposed SPAs in the Scottish MPA network

Proposed Representation Replication Geographic range Linkages SPAs

Pentland Firth Supports a Arctic skua (breeding) is Provides an example Birds in the Pentland Firth are within breeding seabird represented within 2 in the Northern Isles foraging range of the nearest breeding assemblage, proposed SPAs and 7 and represents the colony at Hoy SPA and potentially also of including 75 Arctic existing colony SPAs, 6 of southern extent of the colonies at Papa Westray, Rousay and skua2. which have marine range of this species West Westray SPAs, but typical foraging extensions. However, in Scotland. ranges of breeding Arctic skua are uncertain

Arctic skua is not the (Thaxter et al, 2012; Humphries et al, 2017)

species determining the Seas off Foula Supports a extension. Provides an example Birds foraging in the Seas off Foula are breeding seabird in the Northern Isles within foraging range of the nearest assemblage, Replication of this feature and represents the breeding colony at Foula SPA and including 219 Arctic in the network is proposed northern extent of the potentially also of colonies at Fair Isle and skua2. in OSPAR Region II. range of this species Fetlar SPAs, but typical foraging ranges of No sites were identified in in Scotland. breeding Arctic skua are uncertain (Thaxter OSPAR Region III. et al, 2012; Humphries et al, 2017).

2 This is an average number of birds within a site, derived from analysis of densities using the ESAS dataset to identify areas of sea that on average held higher and more aggregated densities of birds than other areas (Kober et al, 2010). Essentially the average figure gives an indication of the relative importance of sites; it represents a snapshot of usage because the entire population of the relevant breeding colonies are not at sea at any one time and are not solely confined to those areas identified as pSPAs. The total number of individuals using the site over the breeding season will be well in excess of the estimate used for site selection purposes and will reflect the breeding populations at colonies within foraging range of the site and turnover within the site.

4. Summary

The species assessment (Table 1) indicates there is an expectation of Arctic skua (breeding) being represented once or twice in the Scottish SPA network.

The proposed Scottish SPA network includes two marine pSPAs for Arctic skua (breeding) holding an average of 294 birds2. Both sites are in OSPAR region II, which holds over 90% of the GB population (Mitchell et al, 2004) and therefore, the pSPA locations reflect the geographic range of this species in Scotland.

The number and distribution of marine proposed sites for Arctic skua (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the species assessment (Table 1) but exceeds the minimum level of representation.

Replication in the network where this overlaps with the Scottish distribution of Arctic skua (breeding) is considered appropriate because Arctic skua (breeding) are vulnerable to changes in food availability and associated interspecific interactions with great skuas. They have also been assessed as vulnerable to extinction in Britain as a consequence of climate change (Russell et al, 2015). Arctic skua are at the southern edge of their breeding range in northern Scotland and the population in Scotland has been declining since the mid-1980s (Foster & Marrs, 2012). In conjunction with wider seas measures, site-based protection of marine areas used regularly by aggregations of Arctic skua (breeding) is considered an appropriate conservation measure to enhance resilience to such threats and pressures.

The pSPAs are collectively within foraging range of at least two of seven breeding colony SPAs in Orkney and Shetland. Inclusion of Arctic skua (breeding) in the Seas off Foula pSPA and Pentland Firth pSPA provides added conservation value by safeguarding marine habitats supporting prey species used by Arctic skua (breeding) from existing colony SPAs.

5. Conclusion

The number and distribution of marine proposed SPAs for Arctic skua (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of Arctic skua (breeding) in Europe.

The case for inclusion of Arctic skua (breeding) at Seas off Foula pSPA and Pentland Firth pSPA is further supported by functional linkages to existing colony SPAs.

No further SPA provision in Scotland's marine environment is considered necessary for Arctic skua (breeding). However, additional conservation measures could be considered to address anthropogenic threats and pressures influencing Arctic skua populations at the wider seas/ecosystem level.

6. References

BirdLife International, 2017. European birds of conservation concern: populations, trends and national responsibilities. Staneva, A. & Burfield, I. (comps.). http://www.birdlife.org/europe-and-central-asia/European-birds-of-conservation-concern

BirdLife International, 2018. Species factsheet, Stercorarius parasiticus. http://www.birdlife.org

Caldow, R.W.G. & Furness, R.W. 2000. The effect of food availability on the foraging behaviour of breeding great skuas Catharacta skua and Arctic skuas Stercorarius parasiticus. Journal of Avian Biology 31, 367-375.

Dawson, N. M., MacLeod, C. D., Smith, M. & Ratcliffe, N. 2011. Interactions with Great Skuas Stercorarius skua as a factor in the long-term decline of an Arctic Skua Stercorarius parasiticus population. Ibis, 153, 143–153. doi:10.1111/j.1474-919X.2010.01065.x

Foster, S. & Marrs, S. 2012. Seabirds in Scotland. Scottish Natural Heritage Trend Note No. 021

Furness, R.W. & Tasker, M.L. 2000. Seabird-fisheries interactions quantifying the sensitivity of seabirds to reductions in sandeel abundance and identification of key areas for sensitive seabirds in the North Sea. Marine Ecology Progress Series, 202, 253-264.

Humphreys, L., Harris, S. & Agombar, D. 2017. Arctic Skuas – tracking the most rapidly declining seabird in the UK. BTO Research project leaflet. https://www.bto.org/sites/default/files/bto-arctic-skua-project-leaflet.pdf

Jones, T., Smith, C., Williams, E. & Ramsay, A. 2008. Breeding performance and diet of Great Skuas Stercorarius skua and Parasitic Jaegers (Arctic Skuas) S. parasiticus on the west coast of Scotland. Bird Study, 55, 257-266.

Kober, K., Webb, A., Win, I., Lewis, M., O’Brien, S., Wilson, L.J. & Reid, J.B. 2010. An analysis of the numbers and distribution of seabirds within the British Fishery Limit aimed at identifying areas that qualify as possible marine SPAs. JNCC report No. 431.

Meek, E.R., Bolton, M., Fox, D. & Remp, J., 2011. Breeding skuas in Orkney: a 2010 census indicates density-dependent population change driven by both food supply and predation. Seabird, 24, 1-10.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Phillips, R.A., Caldow, R.W.G. & Furness, R.W. 1996. The influence of food availability on the breeding performance and reproductive success of Arctic Skuas. Ibis. 138, 410-419.

Russell, D.J.F., Wanless, S., Collingham, Y.C., Huntley, B. & Hamer, K.C. 2015. Predicting future European breeding distributions of British seabird species under climate change and unlimited/no dispersal scenarios. Diversity – Basel, 7, 342-359.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Stone, C.J., Webb, A., Barton, C., Ratcliffe, N., Reed, T.C., Tasker, M.L., Camphuysen, C.J. & Pienkowski, M.W. 1995. An atlas of seabird distribution in north-west European waters. JNCC. ISBN 1 873701 94 2.

Thaxter, C.B., Lascelles, B., Sugar, K., Cook, A.S.C.P., Roos, S., Bolton, M., Langston, R.H.W. & Burton, N.H.K. 2012. Seabird foraging ranges as a preliminary tool for identifying candidate Marine Protected Areas. Biological Conservation, 156, 53-61.

Arctic tern (breeding)

1. Introduction

Arctic tern is an Annex 1 species. Arctic tern (breeding) is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for Arctic tern (breeding)

2. Species account

Table 1 Summary of status of Arctic tern (breeding)

Species’ status Score Notes

GB marine Moderately Breeding Arctic terns forage in inshore waters, typically within c.25 -30km of their colonies (Wilson et distribution restricted al, 2014; Thaxter et al, 2012) although failed or non-breeders range further when present in the Northern hemisphere during the summer months. This is reflected in the observed at-sea distribution, with the highest densities largely confined to the vicinity of breeding concentrations in the Scottish islands and north-east England (Bradbury et al, 2017). Significance of High Arctic terns breeding in GB have a predominantly northerly distribution with the majority of colonies Scotland’s seas found in the Northern Isles and Outer Hebrides (Mitchell et al, 2004). The Seabird 2000 national in GB context census of breeding seabirds in Britain and Ireland found a total GB population of 52,600 pairs of which 47,300 (90%) were in Scotland (Mitchell et al, 2004). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this Annex 1 species is to biogeographic 52,600 pairs which represents 2.9 – 3.5% of the biogeographic population (Europe and North population Atlantic) estimated at 1,493,000 - 1,800,000 pairs (Mitchell et al, 2004).

Arctic tern has a circumpolar breeding range across the Arctic and subarctic regions of Europe, Asia and North America as far south as Northern France and Massachusetts (U.S.A.). It is a transequatorial migrant wintering throughout the Southern Ocean to the edge of the Antarctic ice and the southern tips of South America and Africa (BirdLife International, 2018). European Least The global and European conservation status for Arctic tern is Least Concern (Secure) (BirdLife population Concern International, 2017 & 2018). conservation status Species’ status summary and The European population status of breeding Arctic tern is considered Least Concern. GB is of assessment of level of Medium importance to the biogeographic population of this Annex 1 species. Arctic tern (breeding) representation in Scottish have a moderately restricted distribution at sea with the highest densities predominantly in vicinity of SPA network. colonies in Scotland, which holds 90% of the GB population. Accordingly, the overall assessment of the relative importance of Scotland’s marine environment to Arctic tern (breeding) in Europe is Medium.

This assessment indicates there is an expectation of Arctic tern (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of Arctic tern (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have either high or medium threats and impacts on relevant populations of Arctic tern (breeding) (Furness, 2016). In particular, Arctic terns are highly pressures vulnerable to depletion of food-fish stocks (Furness & Tasker, 2000) and sandeel stock declines have been associated with breeding failure and with reduced growth and survival of Arctic tern chicks (Monaghan et al 1992).

Arctic terns are potentially sensitive to bycatch in longline fisheries (ICES, 2013) but are not identified as among the more sensitive species to bycatch in fisheries operating in UK waters (Bradbury et al, 2017). Arctic tern may be highly sensitive to changes in water turbidity but potential exposure of breeding Arctic terns in GB waters to relevant activities such as marine aggregate extraction operations appears limited and impacts on populations are undocumented (Cook & Burton, 2010).

Arctic tern populations in the UK are also highly susceptible to climatic fluctuations or change (Möller et al, 2006; Huntley et al, 2007; Pearce-Higgins et al, 2011; Russell et al, 2015). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Arctic tern populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of Arctic tern (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Arctic tern (breeding) is being considered for inclusion at two marine proposed SPAs and is a feature at 12 existing colony SPAs, 6 of which have marine extensions. The marine proposed SPAs encompass the foraging areas used by breeding terns from existing colony SPAs. The foraging areas used by Arctic terns extend beyond the existing marine extensions which are classified to protect areas used by puffin, guillemot, razorbill, gannet, kittiwake and/or fulmar for maintenance behaviours close to the colony such as preening, loafing and roosting.

Table 3 Summary of occurrence of Arctic tern (breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Pentland Firth Supports Arctic tern (breeding) is Provides only example in the Birds foraging in the approximately 2% represented within 2 marine Northern Isles Pentland Firth are within of the GB breeding proposed SPAs and at 12 foraging range of the population. existing colony SPAs, six of Pentland Firth Islands SPA

which have marine extensions. colonies (Wilson et al, However, Arctic tern is not the 2014). Outer Firth of Supports species determining the Provides only example on the Birds foraging in the Outer Forth and St approximately 1% extension. east mainland coast and Firth of Forth and St Andrews Bay of the GB breeding Replication of this feature in the represents the southern Andrews Bay Complex are Complex population. network is proposed in OSPAR extent of the range of this within foraging range of Region II. species in Scotland. breeding colony at Forth Islands SPA (Wilson et al, No sites were identified in OSPAR Region III. 2014).

4. Summary

The species assessment (Table 1) indicates there is an expectation of Arctic tern (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes two marine pSPAs for Arctic tern (breeding) supporting c. 3% of the GB population. There are no proposed sites in OSPAR Region III, which includes waters used by foraging Arctic terns from colonies in the Outer Hebrides and on the west coast. There is replication within OSPAR Region II, which holds the majority (c.85%) of the Scottish population, but no sites in Shetland, which in 1998-2002 held 52% of the Scottish and 47% of the GB population (Mitchell et al, 2004).

The number and distribution of marine proposed SPAs for Arctic tern (breeding) in the Scottish network, as summarised above and in Table 3, is below the minimum indicated by the species assessment (Table 1).

Replication in the network where this overlaps with the Scottish distribution of Arctic tern (breeding) is considered appropriate. This is because Arctic tern is an Annex 1 species and there is evidence that Arctic terns (breeding) are vulnerable to pressures or threats likely to cause either high or medium impacts on relevant populations where site-based protection would enhance resilience of the species in Scotland. In particular, Arctic tern populations are vulnerable to depletion of preferred prey, principally sandeels.

Additional replication in the network is desirable, but major declines and erratic breeding performance in SPA colonies in Scotland, and particularly Shetland, since the Seabird 2000 census pose a challenge to robust site identification.

There are functional linkages between the marine pSPAs and existing colony SPAs; the proposed sites encompass core modelled foraging areas for breeding Arctic terns from the Pentland Firth Islands SPA and Forth Islands SPA (Wilson et al, 2014).

5. Conclusion

The number and distribution of marine proposed SPAs for Arctic tern (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of Arctic tern (breeding) in Europe.

The case for inclusion of Arctic tern (breeding) in the Outer Firth of Forth and St Andrews Bay Complex pSPA and Pentland Firth pSPA is further supported because it provides added conservation value to the Scottish marine SPA network by safeguarding the foraging habitats and prey species used by Arctic tern (breeding) from existing colony SPAs.

Further SPA provision in OSPAR Region III or additional site-based and/or alternative conservation measures are recommended for Arctic tern (breeding). Potentially suitable additional SPAs could probably be identified with relatively little additional work.

6. References

BirdLife International, 2018. Species factsheet, Sterna paradisaea. http://www.birdlife.org

Cook, A.S.C.P. & Burton, N.H.K. 2010. A review of the potential impacts of marine aggregate extraction on seabirds. Marine Environment Protection Fund Project 09/P130. British Trust for Ornithology. Thetford, Norfolk, UK.

Huntley, B., Green, R.E., Collingham, Y.C. & Willis, S.G. 2007. A climatic atlas of European breeding birds. Durham University, RSPB and Lynx Edicions, Barcelona. 521 pp.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Möller, A.P., Flensted-Jensen, E. & Mardal, W. 2006. Dispersal and climate change: a case study of the Arctic tern Sterna paradisaea. Global Change Biology 12, 2005-2013.

Monaghan, P., Uttley, J.D. & Burns, M.D. 1992. Effect of changes in food availability on reproductive effort in Arctic Terns Sterna paradisaea. Ardea, 80, 71-81.

Pearce-Higgins, J.W., Johnston, A., Ausden, M., Dodd, A., Newson, S.E., Ockendon, N., Thaxter, C.B., Bradbury, R.B., Chamberlain, D.E, Jiguet, F., Rehfisch, M.M. & Thomas, C.D. 2011. Final Report to the Climate Change Impacts on Avian Interests of Protected Area Networks (CHAINSPAN) Steering Group. BTO Report to DEFRA. http://randd.defra.gov.uk/Document.aspx?Document=9962_CHAINSPANFINALREPORT.pdf

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wilson L. J., Black J., Brewer, M. J., Potts, J. M., Kuepfer, A., Win I., Kober K., Bingham C., Mavor, R. & Webb, A. 2014. Quantifying usage of the marine environment by terns Sterna sp. around their breeding colony SPAs. JNCC Report No. 500.

Atlantic puffin (breeding)

1. Introduction

Atlantic puffin is a regularly occurring migratory species. Atlantic puffin (breeding) is being considered for inclusion within three marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for Atlantic puffin (breeding)

2. Species account

Table 1 Summary of status of Atlantic puffin (breeding)

Species’ status Score Notes

GB marine Widespread Atlantic puffin (breeding) have a widespread distribution in the GB marine environment (JNCC range distribution score 89.4%1). Modelling of boat-based and aerial survey data across UK waters shows the highest densities as: along the North Sea coast from Aberdeen to Yorkshire, with a particular concentration off the Firth of Forth; around the Northern Isles; in the northern half of the Minch and west of Lewis and Harris to St Kilda; and, off SW Wales (Bradbury et al, 2017). The modelled distribution at sea is consistent with both recent GPS tracking studies (Harris et al, 2012)2 and earlier studies (e.g. Anker- Nilssen & Lorentsen,1990) indicating that breeding puffins typically feed close to their colonies but are also capable of much longer distance foraging trips. Significance of High The at sea distribution reflects that of breeding colonies of Atlantic puffin in GB with 85% of breeding Scotland’s seas birds in Scotland; the largest colonies at St Kilda and the Shiants in the Outer Hebrides together hold in GB context over a third of the GB total and colonies in Shetland and Orkney a further 29% (Mitchell et al, 2004). On the North Sea coast the colonies at the Farnes in Northumbria and in the Firth of Forth together represent 17% of the GB total (ibid). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 579,500 pairs equivalent to 9.1 – 10.9% of the very large biogeographic population population (subspecies artica, Atlantic) estimated at 5,500,000 – 6,600,000 pairs (Mitchell et al, 2004).

Atlantic Puffin breed on coasts and islands throughout the North Atlantic from Newfoundland and Maine through Greenland, Iceland, Norway and north-west Russia to Britain, Ireland and France (BirdLife International, 2018; Mitchell et al, 2004). European Vulnerable The European and global population status of this regularly occurring migratory species is Vulnerable population (BirdLife International, 2017 & 2018). This reflects rapid declines in breeding populations across most conservation of the Atlantic puffin’s European range, particularly in Norway and Iceland. Population trends outside status Europe are unknown.

1 Derived from the distribution models in WWT Consulting (2016) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 https://www.birdguides.com/articles/tracking-the-sea-parrot-a-new-approach-to-puffin-conservation/ 16

Species’ status summary and Breeding Atlantic puffin in GB are of Medium importance to the very large biogeographic population of assessment of level of this regularly occurring migratory species and the European population status is considered representation in Scottish Vulnerable. Atlantic puffin (breeding) have a widespread distribution at sea, with the highest densities SPA network. in Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of Atlantic puffin (breeding) in Europe is Medium.

This assessment indicates there is an expectation of Atlantic puffin (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of Atlantic puffin (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have high or threats and medium impacts on relevant populations of Atlantic puffin (breeding) (Furness, 2016). Atlantic puffin are dependent pressures on high quality fish, such as juvenile sandeels or herring, for successful chick rearing (Wanless et al, 2005; Harris et al, 2007; Miles et al, 2015) and are susceptible to overfishing of food fish stocks (e.g. the collapse of Norwegian herring stocks has resulted in sustained breeding failure for puffins at major colonies in Norway) (Tasker et al, 2000). Recent studies in Canada have also linked adult Atlantic puffin survival rates to herring stocks (Breton & Diamond, 2014).

Atlantic puffin and closely related species have been recorded as bycatch in a number of gillnet fisheries (e.g. for cod off Atlantic Canada) but there is no evidence of population level impacts (Tasker et al, 2000; Žydelis et al, 2013).

Atlantic puffin are identified as among the most potentially vulnerable species to bycatch in surface gears in UK waters given their susceptibility to entanglement (Bradbury et al, 2017), but there is no systematic data from which to assess bycatch rates or impacts (ibid).

Changes in sandeel productivity and energy content (Wanless et al, 2005) are potentially linked to climate change and puffins are also susceptible to flooding of their nest burrows during exceptional rainfall events during the breeding season3 and to winter “wrecks” (Jessop, 2014)4. Breeding populations of Atlantic puffin in Europe are predicted to experience range contraction as a consequence of climate change (Russell et al, 2015) and the UK SPA population is projected to decline by at least 25% in response to climate change over the next 40 years under a

3 See e.g. https://www.nationaltrust.org.uk/farne-islands/features/wildlife-review-2015 4 See Return Rates and Survival Rates in http://jncc.defra.gov.uk/page-2966 for discussion of impact of 203/14 winter “wreck” on Skomer colony 17

medium emissions scenario (Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Atlantic puffin (breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of Atlantic puffin (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Atlantic puffin (breeding) are being considered for inclusion at three marine proposed SPAs and are represented in fifteen existing colony SPAs, all of which have marine extensions for puffin maintenance behaviours.

Table 3 Summary of occurrence of Atlantic puffin (breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports a Atlantic puffin (breeding) is Provides only Birds foraging in the Outer Firth of Forth Forth and St breeding seabird represented within three example on the east and St Andrews Bay Complex are Andrews Bay assemblage, proposed SPAs and 15 mainland coast and within mean foraging range (4km, Complex including 61,086 existing colony SPAs, all of represents southern Thaxter et al, 2012) of the breeding Atlantic puffin5. which have marine extent of the range of colony at Forth Islands SPA and extensions for puffin this species in additionally within mean maximum maintenance behaviours. Scotland. foraging range (105.4km, Thaxter et al, Replication of this feature in 2012) of two English SPA colonies.

5 This is an average number of birds within a site, derived from analysis of densities using the ESAS dataset to identify areas of sea that on average held higher and more aggregated densities of birds than other areas (Kober et al, 2010). Essentially the average figure gives an indication of the relative importance of sites; it represents a snapshot of usage because the entire population of the relevant breeding colonies are not at sea at any one time and are not solely confined to those areas identified as pSPAs. The total number of individuals using the site over the breeding season will be well in excess of the estimate used for site selection purposes and will reflect the breeding populations at colonies within foraging range of the site and turnover within the site.

Proposed SPAs Representation Replication Geographic range Linkages

Seas off Foula Supports a the network is proposed in Provides an example Birds foraging in the Seas off Foula are breeding seabird OSPAR Region II. in the Northern Isles within mean foraging range (see above) assemblage, and represents the of the breeding colony at Foula SPA including 14,886 northern extent of the and within mean maximum foraging Atlantic puffin5. range of this species range of three additional colony SPAs in Scotland. in Shetland. Seas off St Kilda Supports a Provides only Birds foraging in the Seas off St Kilda breeding seabird example of this are within mean foraging range (see assemblage, species on the west above) of breeding colony at St Kilda including 6,198 coast of Scotland. SPA and within mean maximum Atlantic puffin5. foraging range of three additional colony SPAs in the Outer Hebrides.

4. Summary

The species assessment (Table 1) indicates there is an expectation of Atlantic puffin (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes three marine pSPAs for Atlantic puffin (breeding) that together hold an average of 82,170 birds5. Two of these pSPAs are within OSPAR region II and the third is mainly in OSPAR region III, with a small part of the site in OSPAR Region V. This distribution reflects the overall distribution of Atlantic puffin within Scotland’s seas, although not the relative importance of OSPAR Region III (Bradbury et al, 2017).

The number and distribution of marine proposed sites for Atlantic puffin (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the species assessment (Table 1) but exceeds the minimum level of representation in OSPAR Region II.

Replication in OSPAR regions overlapping the Scottish distribution of Atlantic puffin (breeding) is considered appropriate because there is evidence that puffin (breeding) populations are potentially vulnerable to a number of threats and pressures associated with activities in the marine environment. In conjunction with wider seas measures, site-based protection of marine areas used regularly by aggregations of Atlantic puffin (breeding) is considered an appropriate conservation measure to enhance resilience to such threats and pressures.

The three pSPAs are collectively within mean maximum foraging range (Thaxter et al, 2012) of nine (of 15) existing colony SPAs in Scotland, including five of the six largest colonies in Scotland. The Outer Firth of Forth and St Andrews Bay Complex pSPA is also within mean maximum foraging range of two colony SPAs in England, including the Farne Islands, which is the third largest colony in GB (Mitchell et al, 2004). Inclusion of the three marine pSPAs in the network provides added conservation value by safeguarding marine habitats supporting prey species used by Atlantic puffin (breeding) from existing colony SPAs.

5. Conclusion

The number and distribution of marine proposed SPAs for Atlantic puffin (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of Atlantic puffin (breeding) in Europe.

The case for inclusion of Atlantic puffin (breeding) in the Outer Firth of Forth and St Andrews Bay Complex pSPA, Seas off St Kilda pSPA and Seas off Foula pSPA is further supported because of the functional linkage with existing colony SPAs.

No further SPA provision in Scotland's marine environment is considered necessary for Atlantic puffin (breeding). However, additional conservation measures could be considered to address anthropogenic threats and pressures influencing Atlantic puffin populations at the wider seas/ecosystem level.

6. References

Anker-Nilssen, T. & Lorentsen, S.-H. 1990. Distribution of Puffins Fratercula arctica feeding off Røst, northern Norway, during the breeding season, in relation to chick growth, prey and oceanographical parameters. Polar Research, 8, 67-76.

BirdLife International, 2018. Species factsheet, Fratercula arctica. http://www.birdlife.org

Breton, A.R. & Diamond, A.W. 2014. Annual survival of adult Atlantic puffins Fratercula arctica is positively correlated with herring Clupea harengus availability. Ibis 156, 35-47

Harris, M.P., Newell, M., Daunt, F., Speakman, J. & Wanless, S. 2007. Snake pipefish Entelurus aequoreus are poor food for seabirds. Ibis 150, 413-415

Harris, M. P., Bogdanova, M. I., Daunt, F. & Wanless, S. 2012. Using GPS technology to assess feeding areas of Atlantic Puffins Fratercula arctica. Ringing and Migration 27, 43- 49.

Jessop, H. 2014. Seabird tragedy in the north-east Atlantic winter 2013-14. Unpublished report, RSPB, Sandy

Miles, W.T.S., Mavor, R., Riddiford, N.J., Harvey, P.V., Riddington, R., Shaw, D.N., Parnaby, D. & Reid, J.M. 2015. Decline in an Atlantic Puffin Population: Evaluation of Magnitude and Mechanisms. PLoS ONE, 10, (7): e0131527.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M. L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531–5

Wanless, S., Harris, M.P., Redman, P. & Speakman, J.R. 2005. Low energy values of fish as a probable cause of a major seabird breeding failure in the North Sea. Marine Ecology Progress Series, 294, 1-8.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

Atlantic puffin (non-breeding)

1. Introduction

Atlantic puffin (non-breeding) is a regularly occurring migratory species. No marine proposed SPAs have been identified for Atlantic puffin (non-breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of Atlantic puffin (non-breeding)

Species’ status Score Notes

GB marine Widespread Atlantic puffin (non-breeding) have a widespread distribution in the GB marine environment (JNCC distribution range score 99.9%1). The highest densities modelled from boat-based and aerial survey data across UK waters are generally offshore to the north of Scotland and in the North Sea to the east of Scotland and north-east England. High densities approach the coast in north Shetland and at the border between Scotland and England, although this could be an artefact of modelling boundaries. It was not possible to confidently model densities for the seas around most of England and Wales (Bradbury et al, 2017). Kober et al (2010) indicate high densities of wintering puffin off the coast of east Scotland, and between Skye and the Western Isles. Significance of Low Harris & Wanless (2007) suggest 20,000 Atlantic puffin winter offshore in Scottish waters, Scotland’s seas representing c. 4% of the estimated number of birds overwintering in the UK (536,514 in GB context individuals; Furness 2015). Owing to the challenges associated with censusing this burrow nesting species, its wide dispersal offshore during winter and its intolerance to carrying tracking devices there is a lack of knowledge around Atlantic puffin wintering behaviour and distribution, and therefore high uncertainty around population estimates (Harris & Wanless, 2007; Furness, 2015). GB contribution Medium The best available estimate of the UK2 wintering population for this regularly occurring migratory to biogeographic species is 536,514 birds (Furness, 2015), which is approximately 4.5% of the biogeographic population population (with connectivity to UK waters) estimated to be 11,840,000 birds (Furness, 2015). There

is high uncertainty around these figures, which could range from greater than 50% less to 80% more (Furness, 2015).

Atlantic puffin breed from north-east Canada and Greenland, south to Maine, Iceland, Faroe Islands, northern Russia south through Norway, and the British Isles to north-west France. Atlantic puffin are usually solitary during winter and highly pelagic. Some individuals reach the Azores, Canary Islands, north-west Africa and the western Mediterranean (Harris & Wanless, 2007). European Endangered The European conservation status for Atlantic puffin is Endangered (BirdLife International, 2015). population The global conservation status is Vulnerable, although population trends outside Europe are conservation unknown (BirdLife International, 2017). status Species’ status summary and Non-breeding Atlantic puffin in GB are of medium importance to the very large biogeographic assessment of level of population of this regularly occurring migratory species. Their European population status is representation in Scottish SPA Endangered. The species has a widespread distribution in UK waters and is highly pelagic, occurring network. mostly offshore, but within GB territorial waters Scotland is thought to be of low importance. Accordingly, the overall assessment of the relative importance of Scotland to Atlantic puffin (non- breeding) in Europe is Low.

This assessment indicates there is an expectation of Atlantic puffin (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of Atlantic puffin (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of Atlantic puffin (non-breeding) (Furness, 2016) including competition with unsustainable pressures exploitation of prey species (Harris & Wanless, 2011; Breton & Diamond, 2014). Lower level impacts include accidental bycatch in fishing nets (Bradbury et al, 2017) and oil spills (Harris & Wanless, 2011). Extreme weather events and storms also pose a threat, with large wrecks recorded following severe winter storms at sea (BirdLife International, 2017).

Atlantic puffin is highly susceptible to the impacts of climate change, such as sea temperature rise and shifts in prey distribution and abundance (Durant et al, 2003; Sandvik et al, 2005). This is particularly during the breeding season but likely during the non-breeding season as well.

Atlantic puffin (non-breeding) populations are vulnerable to medium and lower level impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by site-based protection.

3. Summary

The species assessment indicates there is an expectation of Atlantic puffin (non-breeding) being represented once or twice in the Scottish SPA network. No sites have been identified for Atlantic puffin (non-breeding) in the Scottish pSPA network which is below the minimum level of representation anticipated by the species assessment (Table 1).

However, Atlantic puffin (non-breeding) are widely dispersed offshore with an unpredictable distribution. There is evidence of Atlantic puffin (non-breeding) being vulnerable to anthropogenic threats and pressures in the marine environment. These primarily exist at the wider ecosystem level and most require appropriate management at a broader scale than is afforded by site-based protection.

4. Conclusion

Significant marine SPA provision is not considered an appropriate conservation measure for Atlantic puffin (non-breeding) due to the widely dispersed and unpredictable nature of their distribution.

Alternative conservation measures could be considered to address anthropogenic threats and pressures influencing Atlantic puffin (non-breeding) populations at the wider seas/ecosystem level.

5. References

BirdLife International, 2015. Fratercula arctica. The IUCN Red List of Threatened Species 2015: e.T22694927A60110592.

BirdLife International, 2017. Fratercula arctica. The IUCN Red List of Threatened Species 2017: e.T22694927A117606911. http://dx.doi.org/10.2305/IUCN.UK.2017- 3.RLTS.T22694927A117606911.en.

Breton, A.R. & Diamond, A.W. 2014. Annual survival of adult Atlantic puffins Fratercula arctica is positively correlated with herring Clupea harengus availability. Ibis 156, 35-47.

Durant, J., Anker-Nilssen, T. & Stenseth, N.C. 2003. Trophic interactions under climate fluctuations: the Atlantic puffin as an example. Proceedings of the Royal Society of London, Series B 270: 1461-1466.

Furness, R.W. 2015. Non-breeding season populations of seabirds in UK waters: Population sizes for Biologically Defined Minimum Population Scales (BDMPS). Natural England Commissioned Reports, 164. http://publications.naturalengland.org.uk/publication/6427568802627584

Harris, M. & Wanless, S. 2007. Atlantic Puffin. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 2: 867 – 871. Scottish Ornithologists’ Club, Aberlady.

Harris, M.P. & Wanless, S. 2011. The Puffin. Poyser, London.

Sandvik, H., Erikstad, K.E., Barrett, R.T. & Yoccoz, N.G. 2005. The effect of climate on adult survival in five species of North Atlantic seabirds. Journal of Animal Ecology, 74(5), 817- 831.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Black-headed gull (non-breeding)

1. Introduction

Black-headed gull is a regularly occurring migratory species. Black-headed gull (non- breeding) is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for black-headed gull (non-breeding)

2. Species account

Table 1 Summary of status of black-headed gull (non-breeding).

Species’ status Score Notes

GB marine Highly Highly restricted distribution in the GB marine environment (JNCC range score 33.7%1). The highest distribution restricted densities modelled from boat-based and aerial survey data across UK waters were in south-east England. Low densities were modelled in the Firth of Forth, Solway Firth, Firth of Clyde and around

Skye (Bradbury et al, 2017), although large areas of UK waters were not mapped as a result of high uncertainty in model estimates. Kober et al (2010) identify black-headed gull (non-breeding) hotspots in the Severn Estuary and Thames Estuary, and along the coast of Galloway, the south coast of England near the Isle of Wight, the coast of Pembrokeshire, and around Blackpool. Lower densities were identified along the south and north west coast of Scotland, and in the Firth of Forth and the Moray Firth. This species forages primarily in terrestrial and intertidal (above mean low water springs) habitats, mainly using marine and estuarine areas as night-time roosts (Tasker, 2007). Significance of Low Burton et al (2013) estimate 199,682 (188,437 – 211,796) black-headed gulls winter in Scotland Scotland’s seas representing c. 9% of the estimated number of birds overwintering in GB (2,155,147 individuals; in GB context Burton et al, 2013)2. GB contribution High The best available estimate of the GB wintering population of this regularly occurring migratory to biogeographic species is 2,155,147 birds (2,093,327 – 2,225,476; Burton et al, 2013)2, which is approximately 51% population of the biogeographic population (west Europe) estimated to be approximately 4,210,000 birds (Wetlands International, 2015).

This species has an extremely large range and breeds from Spain, France, UK, Iceland and Norway eastwards across Europe and Asia to the Pacific coast. Small numbers breed on the east coast of North America. Birds breeding on the coast of Europe are largely sedentary in winter but other populations tend to migrate. In Scotland, overwintering birds are most commonly found on the east and south-west coasts. Some Scottish breeding birds winter in England and Ireland. An influx of wintering birds move into western Europe with others reaching coastal equatorial Africa, Arabia, the

1 Derived from the distribution models in WWT Consulting (2016) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Data are calculated from counts of birds wintering in terrestrial and near-shore coastal waters; birds roosting offshore or not visible from land are not included, which therefore may underestimate populations.

Indian sub-continent, south-east Asia and the east coast of North America. Wintering birds feed in coastal and inland sites and roost overnight on lochs, reservoirs and estuaries (Tasker, 2007). European Least The global and European conservation status for black-headed gull is Least Concern (BirdLife population Concern International, 2015 & 2017). conservation status Species’ status summary and The European population status of black-headed gull (non-breeding) is considered Least Concern assessment of level of although GB is of High importance to the very high biogeographic population of this regularly occurring representation in Scottish migratory species. Black-headed gulls (non-breeding) have a highly restricted distribution at sea, with SPA network. the highest densities in south-east England (Bradbury et al, 2017). Hotspots were identified in the Severn Estuary and Thames Estuary, and along the coast of Galloway, the south coast of England near the Isle of Wight, the coast of Pembrokeshire, and around Blackpool (Kober et al, 2010). Low densities were estimated in the Firth of Forth, Solway Firth, Firth of Clyde, and around Skye (WWT Consulting, 2016). This species forages primarily in terrestrial and intertidal (above mean low water springs) habitats, mainly using marine and estuarine areas as night-time roosts (Tasker, 2007). Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of black-headed gull (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of black-headed gull (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of black-headed gull (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence that offshore wind development is a medium threat to relevant populations of black-headed gull threats and (non-breeding) in UK waters, primarily as a result of potential collision with turbines (Furness et al, 2013; Furness, pressures 2016). Lower level impacts include accidental entanglement in fragments of fishing net and other plastic waste (Mendel et al, 2008) and potential infection with H5N1 through interactions with farmed birds (Ramis et al, 2014). Black-headed gull have also been identified as at risk of accidental bycatch in some fisheries (ICES, 2013). Breeding populations are vulnerable to depredation by introduced and native mammalian predators (Tasker, 2007).

The potential impacts of climate change on black-headed gull in the UK are unclear, although one model suggests breeding populations may increase as a result of climate change (Pearce-Higgins et al, 2011). High uncertainty is associated with this prediction and until more evidence is available well-managed protected sites are likely to be important to promoting the resilience of species and habitats to potential impacts of climate change with larger areas

of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Black-headed gull (non-breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures. Replication within the network should be considered.

3. Contribution to Scottish SPA network

This section considers the occurrence of black-headed gull (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Black-headed gull (non-breeding) are being considered for inclusion at two marine proposed SPA and are not represented in any existing colony SPAs in Scotland.

Table 3 Summary of occurrence of black-headed gull (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports a non- Black-headed gull (non- Provides only example of this No known linkages. Forth & St breeding seabird breeding) is represented within species on the east coast of Andrews Bay assemblage, 2 proposed SPAs. Scotland. Complex including black- There are no existing SPAs for headed gull with this species in Scotland.

equivalent to c. There is no replication of this 1.2% of the GB feature in the OSPAR regions. non-breeding population.

Proposed SPAs Representation Replication Geographic range Linkages

Solway Firth Supports a non- Provides only example of this No known linkages. breeding waterbird species on the west coast of assemblage, Scotland. including black- headed gull with equivalent to c. 0.6% of the GB non-breeding population.

4. Summary

The species assessment (Table 1) indicates there is an expectation of black-headed gull (non-breeding) being represented once or twice in the Scottish SPA network.

The proposed Scottish SPA network includes two marine pSPAs for black-headed gull (non- breeding) supporting c. 1.8% of the GB non-breeding population2. The pSPAs occur in OSPAR Regions II and III. The proposed SPA locations reflect this species’ habit of foraging primarily in terrestrial and intertidal (above mean low water springs) habitats, mainly using marine and estuarine areas as night-time roosts (Tasker, 2007). The site selection is based on counts of birds wintering in terrestrial and near-shore coastal waters. The proposed SPAs overlap with marine areas estimated to hold some of the highest densities of wintering black- headed gull in Scotland (Kober et al, 2010; Bradbury et al, 2017).

The number and distribution of marine proposed sites for black-headed gull (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with species assessment (Table 1) but exceeds the minimum level of representation.

Replication in the network is considered appropriate because there is evidence of medium threat to relevant populations of black-headed gull (non-breeding) in UK waters from potential collision with wind turbines (Furness et al, 2013, Furness, 2016). Black-headed gull have also been identified as at risk of accidental bycatch in some fisheries (ICES, 2013). Breeding populations are vulnerable to depredation by introduced and native mammalian predators (Tasker, 2007). The potential impacts of climate change on black-headed gull in the UK are unclear, although one model suggests breeding populations may increase as a result of climate change (Pearce-Higgins et al, 2011). High uncertainty is associated with this prediction.

5. Conclusion

The number and distribution of marine proposed SPAs for black-headed gull (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of black-headed gull (non-breeding) in Europe.

The marine extension to the Upper Solway Flats and Marshes SPA forming the Solway Firth pSPA will incorporate black-headed gull as a named qualifier of the waterbird assemblage and provides added conservation value by encompassing the full range of intertidal and subtidal habitats used by roosting non-breeding black-headed gull at this location.

No further SPA provision in Scotland's marine environment is considered necessary for black-headed gull (non-breeding).

6. References

BirdLife International, 2015. Larus ridibundus. The IUCN Red List of Threatened Species 2015: e.T22694420A60087749.

BirdLife International, 2017. Larus ridibundus (amended version of 2016 assessment). The IUCN Red List of Threatened Species 2017: e.T22694420A111823721. http://dx.doi.org/10.2305/IUCN.UK.2017-1.RLTS.T22694420A111823721.en.

Burton, N.H.K., Banks, A.N., Calladine, J.R. & Austin, G.E. 2013. The importance of the United Kingdom for wintering gulls: population estimates and conservation requirements. Bird Study, 60 (1), 87-101.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

ICES. 2013. Report of the Workshop to Review and Advise on Seabird Bycatch (WKBYCS), 14–18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM:77.

Kober, K., Webb, A., Win, I., Lewis, M., O’Brien, S, Wilson, L.J. & Reid, J.B., 2010. An analysis of the numbers and distribution of seabirds within the British Fishery Limit aimed at identifying areas that qualify as possible marine SPAs, JNCC Report 431, ISSN 0963-8091.

Mendel, B., Sonntag, N., Wahl, J., Schwemmer, P., Dries, H., Guse, N., Müller, S. & Garthe, S. 2008. Profiles of seabirds and waterbirds of the German North and Baltic Seas. Distribution, ecology and sensitivities to human activities within the marine environment. Federal Agency for Nature Conservation, Bonn.

Ramis, A., van Amerongen, G., van de Bildt, M., Leijten, L., Vanderstichel, R., Osterhaus, A. & Kuiken, T. 2014. Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus). Veterinary Research, 45, (84).

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M. 2007. Black-headed Gull. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 754 – 758. Scottish Ornithologists’ Club, Aberlady.

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

Black-legged kittiwake (breeding)

1. Introduction

Black-legged kittiwake is a regularly occurring migratory species. Black-legged kittiwake (breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for black-legged kittiwake (breeding)

2. Species account

Table 1 Summary of status of black-legged kittiwake (breeding).

Species’ status Score Notes

GB marine Widespread Black-legged kittiwake (breeding) have a widespread distribution in the GB marine environment distribution (JNCC range score 90.9%1). The highest densities modelled from boat-based and aerial survey data across UK waters were in inshore waters along the North Sea coasts of England and Scotland from the Humber north and over the Dogger Bank. Moderate densities were modelled over a larger area of the North Sea, extending around Orkney and the north coast of Scotland, along parts of the shelf break west of Shetland and in parts of the Irish Sea (Bradbury et al, 2017). This pattern is largely consistent with that in Stone et al (1995) and with models of kittiwake distribution at sea based on tracking studies (Wakefield et al, 2017). Significance of Medium The at-sea pattern of usage reflects the distribution of breeding colonies of black-legged kittiwake in Scotland’s seas GB. At the time of the last full seabird census in Britain the largest and most numerous colonies were in GB context found along North sea coasts of northeast England and eastern Scotland, in the Northern isles and in northwest Scotland (Mitchell et al, 2004). Subsequent rapid declines in the GB breeding population have been most evident in the Northern Isles and Outer Hebrides2. Hence, the relative importance of Scotland, which in 1998-2002 held 77% of the GB breeding population (Mitchell et al, 2004) has declined, but the current overall population and distribution of kittiwake in GB is unknown. GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic (uncertain) migratory species is 366,800 pairs, equivalent to 12.3 – 14.8% of the biogeographic population population (tridactyla North Atlantic, east to Novaya Zemlya) estimated at 2,500,000 - 3,000,000 pairs (Mitchell et al, 2004). However, breeding numbers of kittiwakes have apparently been declining throughout most of the North Atlantic over recent years, including GB (see above) so current proportion of the biogeographic population in GB is uncertain (Furness, 2015).

The nominate (North Atlantic) race of black-legged kittiwake breeds in northern North America, Green- land, Iceland and in NW Europe as far south as Spain (BirdLife International, 2018; Mitchell et al, 2004).

European Vulnerable The global conservation status for black-legged kittiwake is Least Concern and the European population conservation status is Vulnerable (BirdLife International, 2017 & 2018). conservation status The conservation statuses differ because although the black-legged kittiwake population is large and distribution is widespread on a global scale, the European population of black-legged kittiwake has experienced steep declines (magnitude 47%) (BirdLife International, 2017). Species’ status summary and The European population status of breeding black-legged kittiwake is considered Vulnerable and GB assessment of level of is of High importance to the very large biogeographic population of this regularly occurring migratory representation in Scottish species. Black-legged kittiwake (breeding) have a widespread distribution at sea, with the highest SPA network. densities along North sea coasts, including Scotland where the majority of the GB breeding population is located. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of black-legged kittiwake (breeding) in Europe is Low.

This assessment indicates there is an expectation of black-legged kittiwake (breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of black-legged kittiwake (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have high or medium impacts on threats and relevant populations of black-legged kittiwake (breeding) (Furness, 2016). These include mortality as a result of pressures collision with offshore wind farm developments and displacement from foraging/commuting areas (Furness et al, 2013). Depletion of prey resources by fishing activities is also a known driver of population declines (Frederiksen et al, 2004). Lower level population impacts include oil spills (Mendel et al, 2008) and organochlorine pollution (Tartu et al, 2015). A reduction in the availability of discards as a result of fisheries management changes could also impact black-legged kittiwakes that forage in association with fishing vessels (Tasker et al, 2000; Bicknell et al, 2013). Black- legged kittiwake are identified as potentially sensitive to bycatch in surface gears in UK waters but there is no empirical evidence of bycatch rates or impacts (Bradbury et al, 2017).

Black-legged kittiwake (breeding) populations are highly vulnerable to the impacts of climate change driven impacts on the population dynamics and distribution of their preferred prey (Sandvik et al, 2014; Russell et al, 2015; Frederiksen et al, 2004). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change

by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Black-legged kittiwake (breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by site-based protection.

3. Contribution to Scottish SPA network

This section considers the occurrence of black-legged kittiwake (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Black-legged kittiwake (breeding) are being considered for inclusion at one marine proposed SPA and are represented in 28 existing colony SPA, all of which have marine extensions classified to protect areas used by various other cliff-nesting seabird species for maintenance behaviours, such as preening, loafing and roosting, close to the colony. Table 3 Summary of occurrence of black-legged kittiwake (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic Linkages range

Outer Firth of Supports a Black-legged kittiwake (breeding) is Provides only Birds foraging in the Outer Firth of Forth and St breeding seabird represented within one proposed SPA example of this Forth and St Andrews Bay Complex Andrews Bay assemblage, and 28 existing SPAs, all of which species in are within mean maximum foraging Complex including 12,020 have marine extensions. However, Scotland. range (Thaxter et al, 2012) of the black-legged kittiwake is not one of the species breeding colonies at Forth Islands kittiwake3. determining the extension. There is no SPA, Fowlsheugh SPA and St Abb’s replication of this feature in the Head to Fast Castle SPA. OSPAR regions.

3 This is an average number of birds within a site, derived from analysis of densities using the ESAS dataset to identify areas of sea that on average held higher and more aggregated densities of birds than other areas (Kober et al, 2010). Essentially the average figure gives an indication of the relative importance of sites; it represents a snapshot of usage because the entire population of the relevant breeding colonies are not at sea at any one time and are not solely confined to those areas identified as pSPAs. The total number of individuals using the site over the breeding season will be well in excess of the estimate used for site selection purposes and will reflect the breeding populations at colonies within foraging range of the site and turnover within the site.

4. Summary

The species assessment (Table 1) indicates there is an expectation of black-legged kittiwake (breeding) being represented once or twice in the Scottish SPA network.

The proposed Scottish SPA network includes one marine pSPA for black-legged kittiwake (breeding) holding an average of 12,020 birds3. The proposed site (Outer Firth of Forth and St Andrews Bay Complex) is at the southern limit of the range of black-legged kittiwake (breeding) in Scotland within OSPAR Region II, which in 1998-2002 held the majority of the population (Mitchell et al, 2004). There are no proposed sites in OSPAR Region III, but the number and size of breeding colonies and associated densities of birds at sea in the breeding season are substantially lower than in OSPAR Region II and no breeding season density hotspots were identified in this region (Kober et al, 2010).

The number of marine proposed sites for black-legged kittiwake (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the level of representation indicated by the species assessment (Table 1).

Black-legged kittiwake (breeding) are widely dispersed with a relatively unpredictable distribution in Scotland posing a challenge to SPA identification of discrete locations. There is evidence that black-legged kittiwake (breeding) are vulnerable to anthropogenic pressures that exist at the wider ecosystem level, most of which require appropriate management at a broader scale than is afforded by site-based protection.

There are functional linkages between the proposed SPA and three existing colony SPAs. Inclusion of the marine pSPA in the network provides added conservation value by safeguarding marine habitats supporting prey species used by black-legged kittiwake (breeding) from these existing colony SPAs.

5. Conclusion

The single marine proposed SPAs for black-legged kittiwake (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of black-legged kittiwake (breeding) in Europe.

The case for inclusion of black-legged kittiwake (breeding) in the Outer Firth of Forth and St Andrews Bay Complex pSPA is further supported because of the functional links with existing colony SPAs.

Significant marine SPA provision is not considered an appropriate conservation measure for this black-legged kittiwake (breeding) due to the widely dispersed and largely unpredictable nature of their distribution. However, additional conservation measures could be considered to address anthropogenic threats and pressures influencing black-legged kittiwake populations at the wider seas/ecosystem level.

6. References

Bicknell, A.W.J., Oro, D., Camphuysen, K. & Votier, S.C. 2013. Potential consequences of discard reform for seabird communities. Journal of Applied Ecology, 50, 649–658

BirdLife International, 2018. Species factsheet, Rissa tridactyla. http://www.birdlife.org

Frederiksen, M., Harris, M.P., Daunt, F., Rothery, P. & Wanless, S. 2004. The role of industrial fisheries and oceanographic change in the decline of North Sea black-legged kittiwakes. Journal of Applied Ecology 41, 1129-1139

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66

Kober, K., Wilson, L.J., Black, J., O’Brien, S., Allen, S., Win, I., Bingham, C. & J.B. Reid. 2012. The identification of possible marine SPAs for seabirds in the UK: The application of Stage 1.1 – 1.4 of the SPA selection guidelines. JNCC Report No 461.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Sandvik, H., Reiertsen, T.K., Erikstad, K.E., Anker-Nilssen, T., Barrett, R.T., Lorentsen, S.H., Systad, G.H. & Myksvoll, M.S. 2014. The decline of Norwegian kittiwake populations: modelling the role of ocean warming. Climate Research, 60, 91-102.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tartu, S., Lendvai, A.Z., Blevin, P., Herzke, D., Bustamante, P., Moe, B., Gabrielsen, G.W., Bustnes, J.O. & Chastel, O. 2015. Increased adrenal responsiveness and delayed hatching date in relation to polychlorinated biphenyl exposure in Arctic-breeding black-legged kittiwakes (Rissa tridactyla). General and Comparative Endocrinology, 219, 165-172.

Tasker, M. L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531–5

Wakefield, E. D., Owen, E., Baer, J., Carroll, M. J., Daunt, F., Dodd, S. G., Green, J. A., Guilford, T., Mavor, R. A., Miller, P. I., Newell, M. A., Newton, S. F., Robertson, G. S., Shoji, A., Soanes, L. M., Votier, S. C., Wanless, S. & Bolton, M. 2017. Breeding density, fine- scale tracking, and large-scale modelling reveal the regional distribution of four seabird species. Ecological Applications, 27, 2074–2091.

Black-legged kittiwake (non-breeding)

1. Introduction

Black-legged kittiwake is a regularly occurring migratory species. Black-legged kittiwake (non-breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for black-legged kittiwake (non-breeding)

2. Species account

Table 1 Summary of status of black-legged kittiwake (non-breeding).

Species’ status Score Notes

GB marine Widespread Very widespread distribution in the GB marine environment (JNCC range score 99.9%1). The highest distribution densities modelled from boat-based and aerial survey data across UK waters were in the Moray Firth, along the shelf-break west of Shetland, along the north coast of Scotland and Orkney, >200km east of Scotland in the North Sea, eastern England (including a hotspot over Dogger Bank), and around south-west England extending into the Celtic Sea. Lesser densities were modelled around the west coast of Scotland and in the English Channel (Bradbury et al, 2017). Significance of Low Although variable, Heubeck (2007) suggests 10,000 black-legged kittiwake winter inshore in Scottish Scotland’s seas waters, representing 0.6-0.8% of the estimated number of birds overwintering in the UK in GB context (1,319,342 - 1,741,523 individuals; Furness, 2015). GB contribution High The best available estimate of the UK2 wintering population for this regularly occurring migratory to biogeographic species is 1,319,342 - 1,741,523 birds (Aug-Dec – Jan-Apr; Furness, 2015), which is approximately population 26-34% of the biogeographic population (with connectivity to UK waters) estimated to be 5,100,000 birds (Furness, 2015). There is high uncertainty around these figures, which could range from greater than 50% less to 80% more (Furness, 2015).

Black-legged kittiwake have a large circumpolar range and breeds throughout the North Atlantic and North Pacific. They are largely pelagic in the non-breeding season. Most breeding black-legged kittiwakes leave Scotland in winter but significant numbers remain in coastal areas and in the North Sea. Birds tend to leave colonies by late August but feeding aggregations may be seen around the Scottish coast until late October/early November. Scottish breeding birds largely overwinter in the West Atlantic, with some birds wintering in the North Sea and the North Atlantic (Heubeck, 2007; Frederiksen et al, 2012).

Population High The global conservation status for black-legged kittiwake is Least Concern, however the European conservation conservation status is Vulnerable (BirdLife International, 2017 & 2018). status The conservation statuses differ because although the black-legged kittiwake population is large and its distribution is widespread on a global scale, the European population of black-legged kittiwake has experienced steep declines (magnitude 47%) (BirdLife International, 2017). Species’ status summary and The UK black-legged kittiwake (non-breeding) population is of high importance to the biogeographic assessment of level of population, although the Scottish wintering population of this regularly occurring migratory species is of representation in Scottish very low importance to the overall UK population. This species’ European population status is SPA network. considered Vulnerable and therefore measures to improve their conservation status are considered to be of high importance. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of black-legged kittiwake (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of black-legged kittiwake (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of black-legged kittiwake (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on high and/or relevant populations of black-legged kittiwake (non-breeding) (Furness, 2016). These primarily include mortality as a medium result of collision with offshore wind farm developments and displacement from foraging/commuting areas (Furness impacts. et al, 2013). Depletion of prey resources by fishing activities is also a known driver of population declines (Frederiksen et al, 2004). Lower level population impacts include oil spills (Mendel et al, 2008), organochlorine pollution (Tartu et al, 2015), accidental bycatch in fishing nets (Bradbury et al, 2017), and outbreaks of bird flu as a result of high mixing of populations during the non-breeding season (OSPAR Commission, 2009; Frederiksen et al, 2012). A reduction in the availability of discards as a result of fisheries management changes could also impact black-legged kittiwakes that forage in association with fishing vessels (Tasker et al, 2000; Bicknell et al, 2013).

Whilst there is no specific evidence on the impacts of climate change to black-legged kittiwakes (non-breeding), it is recognised that well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing

other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Black-legged kittiwake (non-breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by site-based protection.

3. Contribution to Scottish SPA network

This section considers the occurrence of black-legged kittiwake (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Black-legged kittiwake (non-breeding) is being considered for inclusion at one marine proposed SPA. There are no existing SPAs for this species in this season in Scotland.

Table 3 Summary of occurrence of black-legged kittiwake (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed Representation Replication Geographic range Linkages SPAs

Outer Firth of Supports a non- Black-legged kittiwake Provides only There is a lack of evidence to assess direct Forth and St breeding seabird (non-breeding) is example of this linkages between breeding colony SPA Andrews Bay assemblage, including represented within one species in Scotland. populations and overwintering populations of Complex black-legged kittiwake proposed SPA. black-legged kittiwake in the pSPA. equivalent to c. 0.2% There are no existing Black-legged kittiwakes tend to be pelagic of the UK non- SPAs for this species in during the non-breeding season Heubeck, 2007; breeding population. this season in Scotland. Frederiksen et al, 2012). However, some birds No sites were identified from the Forth Islands SPA (Isle of May) winter in OSPAR Region III. in the North Sea (Frederiksen et al, 2012). These birds could occur in the pSPA, as could birds from other east coast SPAs. Breeding birds from the Isle of May that winter in the North Sea tend to be successful breeders (Bogdanova et al, 2011).

4. Summary

This assessment indicates there is an expectation of black-legged kittiwake (non-breeding) being represented once or twice in the Scottish SPA network.

The Scottish SPA network includes one marine proposed SPA in OSPAR Region II for black-legged kittiwake (non-breeding) supporting c. 0.2% of the UK non-breeding population. The proposed SPAs network does not reflect the full geographic range and variation of black-legged kittiwake (non-breeding) in Scotland. Non-breeding black-legged kittiwake occur in the Moray Firth, along the shelf-break west of Shetland, along the north coast of Scotland and Orkney, and >200km east of Scotland in the North Sea (Bradbury et al, 2017).

The number and distribution of proposed sites for black-legged kittiwake (non-breeding) in the Scottish pSPA network as summarised above is consistent with the level of representation anticipated by the species assessment (Table 1).

Black-legged kittiwakes (non-breeding) are widely dispersed with an unpredictable distribution. Black-legged kittiwake (non-breeding) are primarily vulnerable to anthropogenic pressures that exist at the wider ecosystem level and are therefore judged not to be most appropriately managed through site-based protection.

There is a lack of evidence to assess direct linkages between SPA populations and overwintering black-legged kittiwakes in the pSPA. However, some birds from the Forth Islands SPA (Isle of May) winter in the North Sea (Frederiksen et al, 2012) and therefore could occur in the pSPA, as could birds from other east coast SPAs. Breeding birds from the Isle of May that winter in the North Sea tend to be successful breeders (Bogdanova et al, 2011).

5. Conclusion

The single marine proposed SPAs for black-legged kittiwake (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of black-legged kittiwake (non-breeding) in Europe.

Significant marine SPA provision is not considered an appropriate conservation measure for black-legged kittiwake (non-breeding) due to the widely dispersed and unpredictable nature of their distribution. However, additional conservation measures could be considered to address anthropogenic threats and pressures influencing black-legged kittiwake populations at the wider seas/ecosystem level.

6. References

Bicknell, A.W.J., Oro, D., Camphuysen, K. & Votier, S.C. 2013. Potential consequences of discard reform for seabird communities. Journal of Applied Ecology, 50, 649–658.

BirdLife International, 2018. Species factsheet, Rissa tridactyla. http://www.birdlife.org .

Bogdanova, M.I., Daunt, F., Newell, M., Phillips, R.A., Harris, M.P. & Wanless, S. 2011. Seasonal interactions in the black-legged kittiwake, Rissa tridactyla: links between breeding

performance and winter distribution. Proceedings of the Royal Society B, DOI: 10.1098/rspb.2010.2601.

Frederiksen, M., Moe, B., Daunt, F., Phillips, R. A., Barrett, R. T., Bogdanova, M. I., Boulinier, T., Chardine, J. W., Chastel, O., Chivers, L. S., Christensen-Dalsgaard, S., Clément-Chastel, C., Colhoun, K., Freeman, R., Gaston, A. J., González-Solís, J., Goutte, A., Grémillet, D., Guilford, T., Jensen, G. H., Krasnov, Y., Lorentsen, S.-H., Mallory, M. L., Newell, M., Olsen, B., Shaw, D., Steen, H., Strøm, H., Systad, G. H., Thórarinsson, T. L. & Anker-Nilssen, T. 2012. Multicolony tracking reveals the winter distribution of a pelagic seabird on an ocean basin scale. Diversity and Distributions, 18, 530–542.

Heubeck, M. 2007. Black-legged kittiwake. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 797 – 800. Scottish Ornithologists’ Club, Aberlady.

OSPAR Commission 2009. Background document for black-legged kittiwake (Rissa tridactyla tridactyla). OSPAR Commission Biodiversity Series.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M. L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531–547.

Black-throated diver (non-breeding)

1. Introduction

Black-throated diver is an Annex 1 species. Black-throated diver (non-breeding) is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for black-throated diver (non-breeding)

2. Species account

Table 1 Summary of status of black-throated diver (non-breeding)

Species’ status Score Notes

GB marine Restricted Black-throated diver occur sparsely in low numbers around parts of the GB coast in winter (present in distribution 41.4% of coastal squares in 2007-11 Atlas and in an average of 12.5% of coastal core WeBS count sectors counted between 2011 and 20151), but are scarce in Shetland, northeast Scotland and the Irish Sea (Balmer et al, 2014). Significance of High Scotland holds the largest numbers and concentrations of black-throated diver (91% of coastal Scotland’s seas core WeBS count sectors with 10 or more birds and 100% of sectors with 50 or more birds1), with in GB context particular concentrations in Orkney, the Outer Hebrides and west coast. Scotland therefore has a particular responsibility for this species. GB contribution Low The GB wintering population of this Annex 1 species is 560 birds (Musgrove et al, 2013) which is to biogeographic approximately 0.15% of the biogeographic population (sub-species artica, Northern Europe & population Western Siberia/Europe) estimated at 250,000 - 500,000 birds (Wetlands International, 2015 & 2018).

Black-throated diver has a wide range across northern latitudes, breeding on large, deep freshwater lakes across northern Europe and Asia (BirdLife International, 2018). The subspecies Gavia arctica arctica occurs from NW Europe to W Siberia and winters along the coasts of NW Europe, the Mediterranean, the Black Sea and the Caspian Sea (HELCOM, 2013). The birds wintering in GB waters are thought to include birds from the GB (Scottish) breeding population, which numbers 190 - 250 pairs (Musgrove et al, 2013), as well as birds from Scandanavia, but there is very little information on post-breeding movements of the Scottish population (Wernham et al, 2002). European Declining The European conservation status for black-throated diver is Declining and the global status is Least population Concern (BirdLife International, 2017 & 2018). conservation status These assessments reflect declines in some populations in Europe (e.g. numbers wintering in the Baltic declined from c.13,000 birds in 1988–1993 to 2,300 birds in 2007–2009 (HELCOM, 2013) and the very large size (c.275,000-1,500,000 individuals) and range of the global population.

1 Data supplied on 14 February 2018 by the British Trust for Ornithology, the Royal Society for the Protection of Birds and the Joint Nature Conservation Committee (the last on behalf of the statutory nature conservation bodies: Natural England, Natural Resources Wales and Scottish Natural Heritage and the Department of Agriculture, Environment and Rural Affairs, Northern Ireland) in association with the Wildfowl and Wetlands Trust 49

Species’ status summary and Black-throated diver (non-breeding) have a restricted distribution in GB inshore waters, mainly in assessment of level of Scotland. GB is of Low importance to the biogeographic wintering population of this Annex 1 species. representation in Scottish The European population status is Declining, and therefore measures to improve conservation status SPA network. are considered to be important. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of black-throated diver (non-breeding) in Europe is Medium.

This assessment indicates there is an expectation of black-throated diver (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of black-throated diver (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have threats and medium impacts on relevant populations of black-throated diver (non-breeding) (Furness, 2016). Black-throated pressures divers exhibit very high sensitivity to visual disturbance associated with vessel movements (Mendel et al, 2008; Dierschke et al, 2012; Jarrett et al, 2018) and are also vulnerable to displacement from offshore wind farms (Furness et al, 2013; Garthe & Hüppop, 2004; Dierschke et al, 2012). Black-throated divers (non-breeding) are also susceptible to entanglement in fishing nets (Dagys & Žydelis, 2002; Mendel et al, 2008; ICES, 2013) and in some areas levels of mortality may be significant (Dierschke et al, 2012). In the UK, black-throated diver populations may be vulnerable (sensitivity scores in top 50% of species rankings) to bycatch in surface gears or at depth near the seabed in the winter months, but there is no empirical evidence of bycatch levels and this species’ avoidance of human activity may limit risk of interaction (Bradbury et al, 2017).

Whilst there is no specific evidence on the impacts of climate change to black-throated diver (non-breeding) it is recognised that well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine proposed SPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Black-throated diver populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of black-throated diver (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Black-throated diver (non-breeding) is being considered for inclusion at two marine proposed SPAs. There are no existing SPAs for this species in the non-breeding season, but in the breeding season the species is a qualifying interest of 12 terrestrial SPAs.

Table 3 Summary of occurrence of black-throated diver (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Scapa Flow Supports c. 9.5% Black-throated diver (non- Provides only example of There is no information on of the GB non- breeding) is represented within this species on the east movements of Scottish birds breeding 2 proposed SPAs. There are no coast of Scotland. between their breeding and population. existing SPAs for this species in wintering sites. The nearest the non-breeding season. terrestrial SPA for breeding Black-throated diver (breeding) black-throated diver is is represented in 12 existing Caithness and Sutherland terrestrial SPAs. Peatlands. West Coast of Supports c. 7.2% No replication of this feature in Provides only example of There is no information on the Outer of the GB non- the OSPAR regions is proposed. this species on the west movements of Scottish birds Hebrides breeding coast of Scotland. between their breeding and population. wintering sites. The nearest terrestrial SPA for breeding black-throated diver is Mointeach Scadabhaigh (North Uist).

4. Summary

The species assessment (Table 1) indicates there is an expectation of black-throated diver (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes two marine proposed SPAs for black-throated diver (non-breeding), one in OSPAR Region II and the other in OSPAR Region III. Together, these two sites represent 16.7% of the GB non-breeding population of this species and are in the Northern Isles and Hebrides where some of the highest densities are found; however no sites were identified within the core range on the northwest coast.

The number and distribution of proposed SPAs for black-throated diver (non-breeding) in the Scottish network, as summarised above and in Table 3, is consistent with the species assessment (Table 1).

Replication in OSPAR regions overlapping the Scottish distribution of black-throated diver (non-breeding) would be desirable because black-throated diver is an Annex 1 species. Replication would also be considered appropriate because there is evidence that black- throated diver (non-breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of black-throated diver (non-breeding) to such threats and pressures.

There is insufficient evidence to assess linkages between existing terrestrial SPAs for breeding black-throated diver and the marine pSPAs.

5. Conclusion

The number and distribution of marine proposed SPAs for black-throated diver (non- breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of black-throated diver (non-breeding) in Europe.

Further SPA provision or additional site-based and/or alternative conservation measures are recommended for black-throated diver (non-breeding). Potentially suitable additional SPAs could probably be identified with relatively little additional work.

6. References

Balmer, D., Gillings, S., Caffrey, B., Swann, B., Downie, I. & Fuller, R. 2014. Bird Atlas 2007-11: The Breeding and Wintering Birds of Britain and Ireland. BTO, BirdWatch Ireland, and SOC. BTO Bird Atlas Mapstore https://app.bto.org/mapstore/StoreServlet

BirdLife International, 2018. Species factsheet, Gavia arctica. http://www.birdlife.org

Dagys, M. & Žydelis, R. (2002) Bird Bycatch in Fishing Nets in Lithuanian Coastal Waters in Wintering Season 2001–2002. Acta Zoologica Lituanica, 12, (3): 276-282

Dierschke, V., K.-M. Exo, B. Mendel & S. Garthe 2012: Threats for Red-throated Divers Gavia stellata and Black-throated Divers G. arctica in breeding, migration and wintering areas: a review with special reference to the German marine areas. Vogelwelt, 133:163–194

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66

Garthe, S. & Hüppop, O. 2004. Scaling possible adverse effects of marine wind farms on seabirds: developing and applying a vulnerability index. Journal of Applied Ecology, 41, 724-734

HELCOM Red List Bird Expert Group 2013. Species Information Sheet Gavia arctica (wintering). http://www.helcom.fi/Red List Species Information Sheet/HELCOM Red List Gavia arctica (wintering population).pdf

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M.2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

Mendel, B, Sonntag, N., Wahl, J., Schwemmer, P., Dries, H., Guse, N., Müller, S. & Garthe, S. 2008. Profiles of seabirds and waterbirds of the German North and Baltic Seas: Distribution, ecology and sensitivities to human activities within the marine environment. Bonn, Bundesamt für Naturschutz.

Musgrove, A., Aebischer, N., Eaton, M., Hearn, R., Newson, S., Noble, D., Parsons, M., Risely, K. & Stroud, D. 2013. Population estimates of birds in Great Britain and the United Kingdom. British Birds, 106, 64-100 (https://www.britishbirds.co.uk/wp- content/uploads/2010/12/APEP3.pdf)

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds.) 2002. Migration Atlas: movements of birds of Britain and Ireland. Poyser, London

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

Common eider – faeroeensis subspecies (non-breeding)

1. Introduction

Common eider – faeroeensis subspecies is a regularly occurring migratory species. Common eider - faeroeensis subspecies (non-breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for common eider – faeroeensis subspecies (non-breeding)

2. Species account

Table 1 Summary of status of common eider – faeroeensis subspecies (non-breeding)

Species’ status Score Notes

GB marine Highly Common eider in mainland GB are from the north-western European nominate subspecies (Somateria distribution restricted mollissima mollissima) but those in Shetland are from the much less numerous S. m. faeroeensis subspecies (Furness et al, 2010; Wetlands International, 2018). The genetics and biometrics of eider in the Orkney islands remain unknown (Furness et al 2010), and for the purposes of selection of marine SPAs in Scotland, eider in the Orkney Islands were classified as Somateria mollissima mollissima (Lawson et al, 2015).

Hence, the known distribution of common eider – faeroeensis subspecies (non-breeding) in GB is entirely restricted to Shetland. Significance of High The entire GB non-breeding population is found in Shetland. Scotland’s seas in GB context GB contribution High The Shetland population of 5,500 common eider (Musgrove et al, 2013) represents 100% of the to biogeographic biogeographic (faeroeensis, Shetland, Orkney Is) population as defined by Wetlands International population and 31-48% of the S. m. faeroeensis subspecies, which also includes 6,000 – 12,000 birds of the (faeroeensis, Faeroe Is) biogeographic population in the Faeroe Islands (Wetlands International, 2015 & 2018). European Vulnerable The European conservation status for common eider (races undifferentiated) is Vulnerable and the population global status is Near Threatened (BirdLife International, 2017 a &b). The European status reflects conservation declines evident in both breeding and wintering grounds since the late 1990s in the largest flyway status population of S. m. mollissima in the Baltic and Wadden Seas. The Shetland faeroeensis population has declined by over 70% between 1977 and 2012 (Heubeck & Mellor, 2013). Species’ status summary and Common eider – faeroeensis subspecies (non-breeding) is restricted to Shetland and hence Scotland assessment of level of is of High importance to the wintering population of this regularly occurring migratory species in both representation in Scottish GB and Europe. The European population status of common eider is considered Vulnerable and SPA network. therefore measures to improve its conservation status are considered to be of high importance.

Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of common eider – faeroeensis subspecies (non-breeding) in Europe is Very High.

This assessment indicates there is an expectation of common eider – faeroeensis subspecies (non-breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of common eider – faeroeensis subspecies (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have threats and medium impacts on relevant populations of common eider (non-breeding) (Furness, 2016). In parts of the Baltic and pressures in lumpsucker fisheries in Iceland and Greenland, large numbers of common eider have been reported drowned in set nets, although population level impacts are unclear (Mendel et al, 2008; Žydelis et al, 2013). Empirical data on bycatch in British waters are lacking, but common eider are identified as among the most sensitive species for bycatch at depth near the seabed, with some areas of relatively high potential vulnerability in the winter months mapped in the vicinity of the Shetland Islands (Bradbury et al, 2017). Common eider populations are also vulnerable to changes in availability of favoured bivalve prey, driven by climate change, commercial fisheries, interaction with non-native species or other environmental pressures (Cervencl et al, 2015; Mendel et al, 2008).

Common eider are attracted to commercial mussel farms (e.g. Cervencl et al, 2015; Heubeck & Mellor, 2013) and this can cause conflict with mussel growers (Ross and Furness, 2000; Varennes, 2013; Waltho & Coulson, 2015) but there is limited evidence around impacts of various methods used to deter eider depredation of farmed mussels on eider populations. Similarly, while barrier effects, habitat loss and mortality through collision have been documented for common eider at offshore windfarms in Denmark and Sweden (Dierschke & Garthe, 2006; Larsen & Guillemette, 2007) population level impacts, particularly in relation to multiple developments, are uncertain (Masden et al, 2009).

Recent studies in Orkney indicate that wintering common eider show medium sensitivity to vessel movements (Jarrett et al, 2018). Eider may be particularly sensitive to disturbance associated with vessel movements and recreational activities, as well as to oil spills, during their flightless moult period when large flocks aggregate in favoured locations (Mendel et al, 2008; Waltho and Coulson, 2015).

Local drivers for the ongoing decreases in the common eider – faeroeensis subspecies population in Shetland are unknown but could include deterrence measures taken at aquaculture sites and depredation by killer whales (Heubeck & Mellor, 2013).

Wintering populations of common eider in the UK are projected to decline in response to climate change (Pearce- Higgins et al, 2011) and rising winter temperatures have been identified as a driver for declines in the mussel stocks that common eider feed on in the Wadden Sea (Nehls et al, 2006). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Common eider populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of common eider – faeroeensis subspecies (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Common eider – faeroeensis subspecies (non-breeding) is being considered for inclusion at one marine proposed SPA. There are no existing SPAs for this species in Scotland.

Table 3 Summary of occurrence of common eider – faeroeensis subspecies (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed Representation Replication Geographic Linkages SPAs range

East Mainland Supports up to Common eider – faeroeensis subspecies (non-breeding) is Provides only No known Coast, 4.4 % of the GB represented within one proposed SPA. There are no existing example of this linkages Shetland non-breeding SPAs for this species in the non-breeding season in Scotland. species in population. There is no replication of this feature in the OSPAR regions. Scotland. The subspecies does not occur in OSPAR region III.

4. Summary

The species assessment (Table 1) indicates there is an expectation of common eider – faeroeensis subspecies (non-breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

The Scottish SPA network includes one marine proposed SPA for common eider – faeroeensis subspecies (non-breeding) within OSPAR Region II (where the species is confirmed), supporting up to 4.4% of the GB non-breeding population. The location of the proposed SPA reflects the geographic range and variation of common eider – faeroeensis subspecies (non-breeding) in Scotland as this subspecies is confined to Shetland.

The proposed number and distribution of proposed sites for common eider – faeroeensis sub-species (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level indicated by the species assessment (Table 1). There is no replication of sites within OSPAR Region II and specifically the Shetland Islands to which this subspecies is confined.

Replication in OSPAR Region II would be considered appropriate because there is evidence that common eider – faeroeensis subspecies (non-breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of common eider – faeroeensis subspecies (non-breeding) to such threats and pressures.

5. Conclusion

The single marine proposed SPA for common eider – faeroeensis subspecies (non- breeding) is fully justified both in terms of meeting the UK SPA Selection guidelines and the relative value of protected areas in Scotland’s marine environment to the conservation of common eider – faeroeensis subspecies (non-breeding) in Europe.

Further SPA provision or additional site-based and/or alternative conservation measures are recommended for common eider – faeroeensis subspecies (non-breeding). Potentially suitable additional SPAs could probably be identified with relatively little additional work.

6. References

BirdLife International, (2017a). European birds of conservation concern: populations, trends and national responsibilities. Staneva, A. & Burfield, I. (comps.). http://www.birdlife.org/europe-and-central-asia/European-birds-of-conservation-concern

BirdLife International, (2017b). Species factsheet: Somateria mollissima. http://www.birdlife.org

Cervencl, A., Troost, K., Dijkman, E., de Jong, M., Smit, C.J., Leopold, M.F. & Ens, B.J. 2015. Distribution of wintering common eider Somateria mollissima in the Dutch Wadden Sea in relation to available food stocks. Marine Biology, 162, 153-168.

Furness, R.W., Mable, B., Savory, F., Griffiths, K., Baillie, S.R. & Heubeck, M. 2010. Subspecies’ status of Common Eiders Somateria mollissima in Shetland based on morphology and DNA. Bird Study, 57, 330-335.

Dierschke, V. & Garthe, S. 2006. Literature review of offshore wind farms with regard to seabirds. BfN-Skripten, 186, 131-198.

Heubeck, M. & Mellor, M. 2013. Recent changes in the status and moulting distribution of Common Eiders Somateria mollissima in Shetland. Seabird, 26, 71-86;

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M. 2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

Larsen, J. K. & Guillemette, M. 2007. Effects of wind turbines on flight behaviour of wintering common eiders: implications for habitat use and collision risk. Journal of Applied Ecology, 44, 516–522

Lawson, J., Kober, K., Win, I., Bingham, C., Buxton, N.E., Mudge, G., Webb, A., Reid, J.B., Black, J., Way, L. & O’Brien, S. 2015. An assessment of numbers of wintering divers, seaduck and grebes in inshore marine areas of Scotland. JNCC Report No 567. JNCC, Peterborough.

Masden, E.A., Haydon, D.T., Fox, A.D., Furness, R.W., Bullman, R. & Desholm, M. 2009. Barriers to movement: impacts of wind farms on migrating birds, ICES Journal of Marine Science, 66 (4), 746–753.

Nehls, G., Diederich, S., Thieltges, D.W. & Strasser, M. 2006. Wadden Sea mussel beds invaded by oysters and slipper limpets: competition or climate control. Helgol Mar Res, 60, 135-143

Ross, B.P. & Furness, R.W. 2000. Minimising the impact of eider ducks on mussel farming. Report. University of Glasgow.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Varennes, É., Hanssen, S.A., Bonardelli, J. & Guillemette M. 2013. Sea duck predation in mussel farms: the best nets for excluding common eiders safely and efficiently. Aquaculture Environment Interactions, 4, 31-39.

Waltho, C. & Coulson, J. 2015. The common eider. Poyser, London.

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates . wpe.wetlands.org

Žydelis, R., Small, C. & French, G 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-88

Common eider – mollissima subspecies (non-breeding)

1. Introduction

Common eider – mollissima subspecies is a regularly occurring migratory species. Common eider - mollissima subspecies (non-breeding) is being considered for inclusion within seven marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for common eider – mollissima subspecies (non-breeding)

2. Species account

Table 1 Summary of status of common eider – mollissima subspecies (non-breeding)

Species’ status Score Notes

GB marine Widespread Common eider in mainland GB are from the north-western European nominate subspecies (Somateria distribution mollissima mollissima) but those in Shetland are from the much less numerous S. m. faeroeensis subspecies (Furness et al, 2010; Wetlands International, 2018). For the purposes of selection of marine SPAs in Scotland, eider in the Orkney Islands were classified as Somateria mollissima mollissima (Lawson et al, 2015).

Common eider mollissima subspecies (non-breeding) winter in coastal waters with access to shallow bivalve beds and have a widespread distribution in GB, with the exception of parts of southwest England and Wales. They were present in 60.6% of coastal squares surveyed for the 2007-11 Atlas (Balmer et al, 2014) and in an average of 42.5% of coastal core WeBS count sectors counted between 2011 and 20151. Significance of High Scotland holds the bulk of the wintering population and highest coastal concentrations, which Scotland’s seas are found in Orkney, along the east mainland coast, northern Argyll and Firth of Clyde (Austin et al, in GB context 2017; Balmer et al, 2014). Significant concentrations elsewhere in GB include northeast English coast, Morecambe Bay, The Wash and East Anglian coast (Balmer et al, 2014; Bradbury et al, 2017). GB contribution Medium The GB wintering population of this regularly occurring migratory subspecies is 55,000 birds to biogeographic (Musgrove et al, 2013) and represents c. 4% of the very large biogeographic (Northern West population European, including Norway and Russia) population of c. 1,300,000 – 1,600,000 birds (Wetlands International, 2015 & 2018).

Common eider is widely, but discontinuously, distributed as a breeding species around the mid- to high-latitude coasts of the northern hemisphere with a global population, in six subspecies, of c. 3.3 to 4 million individuals (BirdLife International, 2017a). The winter range is more compressed, with migratory northern populations largely wintering within the range of sedentary populations further south. Eiders breeding in GB are largely sedentary, but east coast Scottish breeders aggregate in the

Firth of Tay in winter and some northern continental birds also winter in GB, mainly on the east coast (Wright et al, 2012). European High The European conservation status for common eider (races undifferentiated) is Vulnerable and the population global status is Near Threatened (BirdLife International, 2017 a & b). The European status reflects conservation declines evident in both breeding and wintering grounds since the late 1990s in the largest flyway status population of S. m. mollissima in the Baltic and Wadden Seas. Species’ status summary and Common eider mollissima subspecies (non-breeding) have a Widespread distribution in GB nearshore assessment of level of waters with the majority of the population and largest aggregations in Scotland. The GB population is representation in Scottish of Medium importance to the very large biogeographic wintering population of this regularly occurring SPA network. migratory subspecies. The European population status of common eider is considered Vulnerable and therefore, measures to improve their conservation status are considered to be of high importance. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of common eider mollissima subspecies (non-breeding) in Europe is Medium.

This assessment indicates there is an expectation of common eider mollissima subspecies (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of common eider – mollissima subspecies (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have threats and medium impacts on relevant populations of common eider (non-breeding) (Furness, 2016). In parts of the Baltic and pressures in lumpsucker fisheries in Iceland and Greenland, large numbers of common eider have been reported drowned in set nets, although population level impacts are unclear (Mendel et al, 2008; Žydelis et al, 2013). Empirical data on bycatch in British waters are lacking, but common eider are identified as among the most sensitive species for bycatch at depth near the seabed, with some areas of relatively high potential vulnerability in the winter months mapped in the vicinity of notable wintering concentrations of common eider along Scotland’s coasts (Bradbury et al, 2017). Common eider populations are also vulnerable to changes in availability of favoured bivalve prey, driven by climate change, commercial fisheries, interaction with non-native species or other environmental pressures (Cervencl et al, 2015; Mendel et al, 2008).

Common eider are attracted to commercial mussel farms (e.g. Cervencl et al, 2015) and this can cause conflict with mussel growers (Ross and Furness, 2000; Varennes, 2013; Waltho & Coulson, 2015) but there is limited evidence around impacts of various methods used to deter eider depredation of farmed mussels on eider populations. Similarly, while barrier effects, habitat loss and mortality through collision have been documented for common eider at offshore windfarms in Denmark and Sweden (Dierschke & Garthe, 2006; Larsen & Guillemette, 2007) population level impacts, particularly in relation to multiple developments, are uncertain (Masden et al, 2009). Recent studies in Orkney indicate that wintering common eider show medium sensitivity to vessel movements (Jarrett et al, 2018). Eider may be particularly sensitive to disturbance associated with vessel movements and recreational activities, as well as to oil spills, during their flightless moult period when large flocks aggregate in favoured locations (Mendel et al, 2008; Waltho and Coulson, 2015).

Common eider populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of common eider – mollissima subspecies (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Common eider – mollissima subspecies (non-breeding) is being considered for inclusion at seven marine proposed SPAs and is a feature of the non-breeding waterbird assemblage at four existing estuarine SPAs, two of which are contiguous with one of the marine proposed SPAs.

Table 3 Summary of occurrence of common eider – mollissima subspecies (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports c. 35.9% of Common eider – Provides an example on the Common eider – mollissima Forth and St the GB non-breeding mollissima subspecies east mainland coast and subspecies (non-breeding) is a Andrews Bay population. (non-breeding) are represents the southern extent feature of the non-breeding Complex represented within 7 of the range of this species in waterbird assemblage of the proposed SPAs and 4 Scotland. Firth of Forth SPA and Firth of existing estuarine Tay and Eden Estuary SPA SPAs. which are contiguous with the Replication of this Outer Firth of Forth and St feature in the network is Andrews Bay Complex pSPA. proposed in OSPAR The eider population in this area Regions II and III. will use both (intertidal) estuarine and (sub-tidal) marine environments. Moray Firth Supports c. 2.9% of Provides an example on the No known linkages. the GB non-breeding east mainland coast in the core population. part of the range of this species Scotland. Scapa Flow Supports c. 3.3% of Provides an example in the No known linkages. the GB non-breeding Northern Isles and represents population. the northern extent of the range of this species in Scotland. North Orkney Supports c. 2.4% of Provides an example in the No known linkages. the GB non-breeding Northern Isles and represents population. the northern extent of the range of this species in Scotland. West Coast of Supports c. 8.5% of Provides only example in the No known linkages. the Outer the GB non-breeding Outer Hebrides, a core part of Hebrides population. the range of this species in Scotland. Coll and Tiree Supports c. 2.4% of Provides only example in the No known linkages.

Proposed SPAs Representation Replication Geographic range Linkages

the GB non-breeding Inner Hebrides, a core part of population. the range of this species in Scotland. Sound of Gigha Supports c. 2.2% of Provides only example on the No known linkages. the GB non-breeding west mainland coast and population. represents the southern extent of the range of this species in Scotland.

4. Summary

This assessment (Table 1) indicates there is an expectation of common eider mollissima subspecies (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes seven marine proposed SPAs for common eider – mollissima subspecies (non-breeding), four in OSPAR Region II and three in region III. These sites together represent c. 57.6% of the GB non-breeding population and reflect the full geographic range and variation of common eider mollissima subspecies (non- breeding) in Scotland from Orkney in the northeast to east coast Firths the Outer Hebrides and coasts of Argyll. The proposed sites also reflect the varied coastal environments in which eider (e.g. from the exposed West Coast of the Outer Hebrides or Coll and Tiree to the more sheltered waters of sites such as Scapa Flow and the Moray Firth).

The number and distribution of marine proposed sites for common eider mollissima subspecies (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is higher than indicated by the species account (Table 1).

However, replication within OSPAR regions is recommended because common eider mollissima subspecies (non-breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of common eider mollissima subspecies (non-breeding) populations to such threats and pressures.

Within the Northern Isles in OSPAR Region II, there are two pSPAs for common eider mollissima subspecies (non-breeding); North Orkney and Scapa Flow. These proposed SPAs represent the northern extent of this species in Scotland together supporting up to 5.7% of the GB population. Of the two Orkney sites, Scapa Flow pSPA holds the third largest number of common eider mollissima subspecies (non-breeding) in the Scottish pSPA network and North Orkney the fifth largest.

The Outer Firth of Forth and St Andrews Bay Complex pSPA on the east coast is contiguous with two existing estuarine SPAs. Together these three sites encompass the full range of habitats used by common eider within the greater Forth.

5. Conclusion

No further SPA provision in Scotland's marine environment is considered necessary for common eider mollissima subspecies (non-breeding) however, a review of the level of representation in the Scottish marine proposed SPA network and in particular, the Northern Isles is required by the Advisory Panel.

6. References

Austin, G., Frost, T., Mellan, H. & Balmer, D. 2017. Results of the third Non-estuarine Waterbird Survey, including population estimates for key waterbird species. British Trust for Ornithology (BTO) Research Report No. 697

Balmer, D., Gillings, S., Caffrey, B., Swann, B., Downie, I. & Fuller, R. 2014. Bird Atlas 2007-11: The Breeding and Wintering Birds of Britain and Ireland. BTO,

BirdWatch Ireland, and SOC. BTO Bird Atlas Mapstore online resource https://app.bto.org/mapstore/StoreServlet

BirdLife International, (2017b). Species factsheet: Somateria mollissima. http://www.birdlife.org

Dierschke, V. & Garthe, S. 2006. Literature review of offshore wind farms with regard to seabirds. BfN-Skripten, 186, 131-198.

Furness, R.W., Mable, B., Savory, F., Griffiths, K., Baillie, S.R. & Heubeck, M. 2010. Subspecies status of Common Eiders Somateria mollissima in Shetland based on morphology and DNA. Bird Study, 57, 330-335.

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M. 2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

Mendel, B, Sonntag, N., Wahl, J., Schwemmer, P., Dries, H., Guse, N., Müller, S. & Garthe, S. 2008. Profiles of seabirds and waterbirds of the German North and Baltic Seas:

Distribution, ecology and sensitivities to human activities within the marine environment. Bonn, Bundesamt für Naturschutz.

Nehls, G., Diederich, S., Thieltges, D.W. & Strasser, M. 2006. Wadden Sea mussel beds invaded by oysters and slipper limpets: competition or climate control. Helgol Mar Res, 60, 135-143

Ross, B.P. & Furness, R.W. 2000. Minimising the impact of eider ducks on mussel farming. Report. University of Glasgow.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Waltho, C. & Coulson, J. 2015. The common eider. Poyser, London.

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates . wpe.wetlands.org

Wright, L.J., Ross-Smith, V.H., Austin, G.E., Massimino, D., Dadam, D., Cook, A.S.C.P., Calbrade, N.A. &. Burton, N.H.K. 2012. Assessing the risk of offshore wind farm development to migratory birds designated as features of UK Special Protection Areas (and other Annex 1 species). BTO Research Report No. 592. Strategic Ornithological Support Services (Project SOSS-05) https://www.bto.org/sites/default/files/u28/downloads/Projects/final-report-soss05.pdf

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-88

Common goldeneye (non-breeding)

1. Introduction

Common goldeneye is a regularly occurring migratory species. Common goldeneye (non- breeding) is being considered for inclusion within three marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for common goldeneye (non-breeding)

2. Species account

Table 1 Summary of status of common goldeneye (non-breeding).

Species’ status Score Notes

GB marine Widespread Common goldeneye (non-breeding) winter in both shallow coastal waters and on freshwater bodies distribution and are very widely distributed across GB, particularly in Scotland and Northern England and Wales

(Balmer et al, 2014). They were present in 70.8% of coastal squares surveyed for the 2007-11 Atlas and in 52.8% of inland squares (Balmer et al, 2014). Common goldeneye were recorded in an average of 36.0% of all c.2700 (coastal and freshwater) core WeBS count sectors counted between 2011 and 2015 and in an average of 40.2% of c. 400 coastal sectors1. Significance of High Scotland holds most of the GB non-estuarine coastal population of common goldeneye (Austin et al, Scotland’s seas 2017), which represents around 10% of the total GB wintering population. The Firth of Forth is in GB context consistently the most important coastal site recorded by WeBS for common goldeneye and both the Firth of Forth and Inner Moray and Beauly Firths are the only coastal sites with populations in excess of 1,000 recorded in the UK since 2000. Hence Scotland has a particular responsibility for common goldeneye wintering in the coastal waters of GB. GB contribution Medium The GB wintering population of this regularly occurring migratory species is 20,000 birds (Musgrove et to biogeographic al, 2013) which is approximately 1.5 -2.0% of the biogeographic population (clangula sub- population species, North-west & Central Europe (winter) estimated at 1,000,000 - 1,300,000 birds (Wetlands International, 2015 & 2018).

Globally, common goldeneye are a very abundant species (c.2,700,000 - 4,700,000 individuals) breeding in boreal forests around the globe. The biogeographic population wintering in North-west & Central Europe breed in Northern and North-west Europe, including a very small number in Scotland (c. 200 pairs; Musgrove et al, 2013). Birds wintering in GB are thought to come from the Scandinavian breeding population (Wright et al, 2012) and the GB wintering numbers are equivalent to c. 10% of number of breeding adults in Sweden (Cramp, 2008).

European Least The global and European conservation status for common goldeneye is Least Concern (Secure) population Concern (BirdLife International, 2017 & 2018). conservation status Species’ status summary and Common goldeneye (non-breeding) have a Widespread distribution in GB nearshore waters and major assessment of level of aggregations are found in Scotland. GB is of Medium importance to the very large biogeographic representation in Scottish wintering population of this regularly occurring migratory species and the European population status SPA network. is considered Least Concern. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of common goldeneye (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of common goldeneye (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of common goldeneye (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is no specifically documented evidence of activities likely to occur in UK coastal waters generating pressures threats and or threats likely to have either high or medium impacts on relevant populations of common goldeneye (non-breeding) pressures (Furness, 2016). However, common goldeneye populations at some major freshwater wintering sites have been impacted by nutrient enrichment (Allen et al, 2004; Tománková et al, 2013) and such pressures could potentially increase the importance of coastal sites in some areas.

Common goldeneye are also a legal quarry species in GB, but in the absence of data on numbers of birds killed annually it is not possible to assess the extent to which legal shooting may contribute to the current population decline (Furness, 2016). Common goldeneye have been reported as bycatch in set net fisheries in the Baltic (ICES, 2013), but there is no evidence of population level impacts.

Significant north-easterly shifts in the wintering range of common goldeneye in NW Europe over the past three decades are attributed to climate change and correlate with an increase of 3.8 °C in early winter temperature in the north-eastern part of the wintering areas (Lehikoinen et al, 2013). Common goldeneye wintering in the UK have been assessed as vulnerable to moderate magnitude declines driven by climate change (Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

3. Contribution to Scottish SPA network

This section considers the occurrence of common goldeneye (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Common goldeneye (non-breeding) is being considered for inclusion at three marine proposed SPAs and is a feature of the non-breeding waterbird assemblage at four existing estuarine/coastal SPAs and three freshwater SPAs. Two of the marine proposed SPAs are contiguous with existing SPAs. Table 3 Summary of occurrence of common goldeneye (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed Representation Replication Geographic range Linkages SPAs

Outer Firth of Supports a non- Common goldeneye Provides an example on Common goldeneye (non-breeding) is a Forth and St breeding waterfowl (non-breeding) is the east mainland coast feature of the non-breeding waterbird Andrews Bay assemblage, represented within 3 and represents the assemblage of the Firth of Forth SPA and Complex including common proposed SPAs and in 4 southern extent of the Firth of Tay and Eden Estuary SPA which goldeneye existing coastal/estuarine range of this species in are contiguous with this marine proposed equivalent to up to SPAs and 3 freshwater Scotland. SPA. The common goldeneye population in c. 2.9% of the GB SPAs. this area will use both (intertidal) estuarine

non-breeding and (sub-tidal) marine environments. Replication of this population. feature in the network is Moray Firth Supports up to c. proposed in OSPAR Provides an example on Common goldeneye (non-breeding) is a 4.5% of the GB Region II. the east mainland coast feature of the non-breeding waterbird non-breeding and represents the core assemblage of the Inner Moray Firth SPA No sites were identified population. part of the coastal range which is contiguous with this marine in OSPAR Region III. of this species on the proposed SPA. The common goldeneye east coast of Scotland. population in this area will use both (intertidal) estuarine and (sub-tidal) marine environments. Scapa Flow Supports up to c. Provides only example in No known linkages to existing SPAs; 1.1% of the GB the Northern Isles and potential for local movements between non-breeding represents the northern freshwater Harray and Stenness SSSI and population. extent of the range of Orkney coastal waters (e.g. in response to this species in Scotland. weather), but no systematic evidence.

4. Summary

The species assessment (Table 1) indicates there is an expectation of common goldeneye (non-breeding) being represented once or twice in the Scottish SPA network.

The Scottish SPA network includes three marine proposed SPAs for common goldeneye (non-breeding) and four existing estuarine SPAs. Non-breeding common goldeneye are also represented at three freshwater SPAs in eastern Scotland. The marine proposed sites support up to 8.5% of the GB non-breeding population with all proposed sites in OSPAR Region II where the highest coastal population densities in Scotland are found (Lawson et al, 2015; WeBS data1). Three of the existing estuarine SPAs for goldeneye (non-breeding) are also in OSPAR Region II and one is in OSPAR Region III. The locations of the marine proposed SPAs do not reflect the full geographic range and variation of common goldeneye (non-breeding) in Scotland’s marine environment with no sites on the west coast or in the Hebrides, but one of the existing estuarine sites is on the west coast (Upper Solway Flats and Marshes SPA).

The number and distribution of marine proposed sites for common goldeneye (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is higher than the level of representation anticipated by the species assessment (Table 1).

There is no direct evidence that non-breeding common goldeneye populations are vulnerable to localised anthropogenic threats and pressures although climate change is believed responsible for observed widescale changes in winter range.

Inclusion of common goldeneye (non-breeding) in the Outer Firth of Forth and St Andrews Bay Complex pSPA and Moray Firth pSPA would provide added conservation value in the marine SPA network as these sites are contiguous with existing estuarine SPAs. Together these encompass the full range of habitats used by common goldeneye (non-breeding) within Scotland’s largest Firths.

5. Conclusion

No further SPA provision in Scotland's marine environment is considered necessary for common goldeneye (non-breeding) however, a review of the level of representation in the Scottish marine proposed SPA network is required by the Advisory Panel.

6. References

Allen, D., Mellon, C. & Enlander, I. 2004. Factors relating to the wintering population of diving ducks on the Lough Neagh System. Report for EHS CON 2/1 (162), Allen & Mellon Environmental Ltd. Belfast.

BirdLife International, 2018. Species factsheet, Bucephala clangula. http://www.birdlife.org

Cramp, S. (ed.). 2008. Birds of the Western Palearctic (BWP): Handbook of the Birds of Europe, the Middle East and North Africa. Interactive DVD edition BWPi (version 2.1) BirdGuides Ltd and Oxford University Press

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark

Lehikoinen, A., Jaatinen, K., Vähätalo, A.V., Clausen, P., Crowe, O., Deceuninck, B., Hearn, R., Holt, C., Hornman, M., Keller, V., Nilsson, L., Langendoen, T., Tománkova, I., Wahl, J. & Fox, A.D. 2013. Rapid climate driven shifts in wintering distributions of three common waterbird species. Global Change Biology, doi: 10.1111/gcb.12200.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tománková, I., Harrod, C., Fox, A.D. & Reid, N. 2014. Chlorophyll-a concentrations and macroinvertebrate declines coincident with collapse of overwintering diving duck populations in a large eutrophic lake. Freshwater Biology, 59, 249-256.

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

Common guillemot (breeding)

1. Introduction

Common guillemot is a regularly occurring migratory species. Common guillemot (breeding) is being considered for inclusion within four proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for common guillemot (breeding)

2. Species account

Table 1 Summary of status of common guillemot (breeding)

Species’ status Score Notes

GB marine Partially Common guillemot (breeding) have a partially restricted distribution in the GB marine environment distribution restricted (JNCC range score 82.3%1). Modelling of boat-based and aerial survey data across UK waters shows consistently high densities in waters extending up to c.50-100km offshore around the east coast of GB from Yorkshire northwards, around Orkney and along the Scottish north and west coasts with highest densities in Moray Firth, off the north-east coast of England and at various locations in vicinity of major colonies in western Scotland (Bradbury et al, 2017). This pattern is consistent with that in Stone et al (1995). Significance of High The distribution of common guillemot at sea in the breeding season reflects that of breeding colonies, Scotland’s seas with 88% of GB breeding birds in Scotland and over 80% of the English population in in GB context Northumberland and Humberside (Mitchell et al, 2004). GB contribution High The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 890,000 pairs2, equivalent to 30.7 – 31.8% of the biogeographic population population (North Atlantic) estimated at 2,800,000 - 2,900,000 pairs (Mitchell et al, 2004).

This species has a circumpolar distribution in the low-arctic and boreal waters of the North Atlantic and North Pacific (BirdLife International, 2018). The two main breeding areas in Europe (North Atlantic) are Britain and Ireland and Iceland, each holding around 1 million pairs, with notable populations also in the Faroes and Norway (Mitchell et al, 2004). The birds in Scotland are from the nominate aalge race, which makes up the majority of the North Atlantic population; the albionis race is found in most of England and Ireland, Wales, Helgoland, France and Iberia and represents around 200,000 pairs (ibid). European Near The European population status of this regularly occurring migratory species is Near Threatened population Threatened (BirdLife International, 2017) and the global status is Least Concern (BirdLife International, 2018). conservation status This reflects a major decline in the population in Iceland (where nearly a quarter of the European population is found) since 2005 against the extremely large size and range of the global population.

1 Derived from the distribution models in WWT Consulting (2016) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Estimated by applying a standard correction factor of x0.67 to counts of individuals attending colonies (Mitchell et al, 2004) 77

Species’ status summary and Breeding common guillemot in GB are of High importance to the very large biogeographic population assessment of level of of this regularly occurring migratory species and the European population status is considered Near representation in Scottish Threatened. Common guillemot (breeding) have a partially restricted distribution at sea, with the SPA network. highest densities in Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of common guillemot (breeding) in Europe is High.

This assessment indicates there is an expectation of common guillemot (breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of common guillemot (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have threats and medium impacts on relevant populations of common guillemot (breeding) (Furness, 2016). In particular, there are pressures reports from set net fisheries throughout the species’ range in both the Atlantic and Pacific Oceans of high levels of common guillemot bycatch (see summaries in Tasker et al, 2000 and Žydelis et al, 2013). The large numbers of guillemots drowned in former coastal salmon fisheries off NE Scotland in the 1990s (Murray et al, 1994) were not thought to have been significant at a population level (Bradbury et al, 2017), but similar fisheries elsewhere (e.g. California) have been associated with historic population declines (Atkins & Heneman, 1987). Common guillemot are identified as among the most potentially vulnerable species to bycatch in both surface gears and at depth near the seabed in UK waters given both their susceptibility to entanglement and their distribution at sea in relation to relevant fishing activity (Bradbury et al, 2017), but there are no systematic data from which to assess bycatch rates or impacts (ibid).

Breeding common guillemot are also susceptible to large scale mortality in major oil spills (Mendel et al, 2008), although impacts on population demographics are complex, with potential for early recruitment to the breeding population to buffer potential population declines (Votier et al, 2008). Guillemots have been identified as showing sensitivity to visual disturbance associated with shipping (Mendel et al, 2008) and are also potentially sensitive to changes in water clarity associated with activities such as dredging (Cook and Burton, 2010) but the impacts are unknown. Similarly, common guillemots have been identified as potentially at relatively high risk of collision with tidal turbines (Furness et al, 2012; McCluskie et al, 2012) but empirical data are lacking.

Changes in sandeel productivity and energy content (Wanless et al, 2005), potentially linked to climate change, have been associated with declines in common guillemot breeding success at colonies in the north and east of the UK3 and breeding populations of common guillemot are predicted to suffer moderate or high magnitude declines in response to climate change over the next 40 years under a medium emissions scenario (Pearce-Higgins et al, 2011) Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Common guillemot (breeding) populations are vulnerable to medium impacts from a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of common guillemot (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Common guillemot (breeding) are being considered for inclusion at four marine proposed SPAs and are represented in 30 existing colony SPAs, all of which have marine extensions for guillemot maintenance behaviours.

Table 3 Summary of occurrence of common guillemot (breeding) within proposed SPAs in the Scottish MPA network

Proposed Representation Replication Geographic range Linkages SPAs

Outer Firth of Supports a Common guillemot Provides only Birds foraging in the Outer Firth of Forth and St Forth and St breeding seabird (breeding) is represented example on the east Andrews Bay Complex are within mean Andrews Bay assemblage within 4 proposed SPAs mainland coast and foraging range (37.8km, Thaxter et al, 2012) of Complex including 28,123 and 30 existing colony represents southern breeding colonies at Forth Islands SPA and St common SPAs, all of which have extent of the range Abb’s Head to Fast Castle SPA and guillemot 4. marine extensions for of this species in

3 http://jncc.defra.gov.uk/page-2898 4 This is an average number of birds within a site, derived from analysis of densities using the ESAS dataset to identify areas of sea that on average held higher and more aggregated densities of birds than other areas (Kober et al, 2010). Essentially the average figure gives an indication of the relative importance of sites; it represents a 79

Proposed Representation Replication Geographic range Linkages SPAs

guillemot maintenance Scotland. additionally within mean maximum foraging behaviours. range (84.2km, Thaxter et al, 2012) of the Replication of this feature Fowlsheugh SPA. Pentland Firth Supports a in the network is proposed Provides an Birds foraging in the Pentland Firth are within breeding seabird in OSPAR Region II. example in the mean foraging range of breeding colonies at assemblage Northern Isles and North Caithness Cliffs SPA, East Caithness including 34,410 represents a core Cliffs SPA, Hoy SPA, Copinsay SPA, Marwick common part of the range of Head SPA and Rousay SPA and within mean guillemot4. this species in maximum foraging range of 3 additional colony Scotland. SPAs in Orkney. Seas off Foula Supports a Provides an Birds foraging in the Seas off Foula are within breeding seabird example in the mean foraging range of breeding colonies at assemblage Northern Isles and Foula SPA, Sumburgh Head SPA, Fair Isle including 11,142 represents the SPA and Noss SPA and within mean common northern extent of maximum foraging range of four additional guillemot4. the range of this SPA colonies in the Northern Isles. species in Scotland. Seas off St Supports a Provides only Birds foraging in the Seas off St Kilda are Kilda breeding seabird example of this within mean foraging range of breeding assemblage, species on the west colonies at St Kilda SPA and Flannan isles including 3,147 coast of Scotland. SPA and additionally within mean maximum common foraging range of Shiant Isles SPA. guillemot4.

snapshot of usage because the entire population of the relevant breeding colonies are not at sea at any one time and are not solely confined to those areas identified as pSPAs. The total number of individuals using the site over the breeding season will be well in excess of the estimate used for site selection purposes and will reflect the breeding populations at colonies within foraging range of the site and turnover within the site.

4. Summary

The proposed Scottish SPA network includes four marine pSPAs for common guillemot (breeding) that together hold an average of 76,822 birds4. Three of these pSPAs are within OSPAR Region II and the fourth mainly in OSPAR Region III, with a small part of the site in OSPAR Region V. This distribution reflects the relative importance of these regions to common guillemot (breeding) in Scotland’s seas (Bradbury et al, 2017).

The number and distribution of marine proposed sites for common guillemot (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation indicated by the species assessment (Table 1) in OSPAR Region III.

Replication in OSPAR Region III would be desirable because common guillemot (breeding) are potentially vulnerable to a number of threats and pressures associated with fisheries, marine pollution, tidal energy capture and climate change. In conjunction with wider seas measures, site-based protection of marine areas used regularly by aggregations of common guillemot (breeding) is considered an appropriate conservation measure to enhance resilience to such threats and pressures.

Within the Northern Isles in OSPAR Region II, there are two pSPAs for common guillemot (breeding); Pentland Firth and Seas off Foula. These pSPAs represent the northern extent of this species in Scotland with Pentland Firth within foraging range of the main breeding colonies on Orkney and the north-east mainland coast, and Seas off Foula within foraging range of the main Shetland colonies. Additional replication in OSPAR Region II helps addresses lack of replication in OSPAR Region III and further enhances resilience.

The four marine pSPAs are collectively within mean maximum foraging range (Thaxter et al, 2012) of 23 (of 30) existing colony SPAs. Inclusion of these four pSPAs in the Scottish marine pSPA network provides added conservation value by safeguarding marine habitats supporting prey species used by common guillemot (breeding) from existing colony SPAs.

5. Conclusion

The number of marine proposed SPAs for common guillemot (breeding) is fully justified5 based on the relative value of protected areas in Scotland’s marine environment to the conservation of common guillemot (breeding) in Europe.

Further SPA provision in OSPAR Region III or additional site-based and/or alternative conservation measures are recommended for common guillemot (breeding). Potentially suitable additional SPAs are currently not known and no other hotspots meeting the population thresholds/regularity requirements for SPA selection were identified for common guillemot (breeding) by the European Seabirds at Sea (ESAS) analysis. Consideration of recent work (tagging and/or additional analyses) would be required to identify potentially suitable sites. Additional conservation measures are recommended to address anthropogenic threats and pressures influencing common guillemot (breeding) populations at the wider seas/ecosystem level.

5 The selection process for Pentland Firth pSPA is currently being reviewed.

The case for inclusion of common guillemot (breeding) at all four marine pSPAs is further supported because of the functional links with existing colony SPAs.

A review of the level of local geographical replication in the Northern Isles is required by the Advisory Panel.

6. References

Atkins, N. & Heneman, B. 1987. The dangers of gill netting to seabirds. American Birds. 41, (5): 1395-1403.

BirdLife International, 2018. Species factsheet, Uria aalge. http://www.birdlife.org

Furness, R.W., Wade, H.M., Robbins, A.M.C. & Masden, E.A. 2012. Assessing the sensitivity of seabird populations to adverse effects from tidal stream turbines and wave energy devices. ICES Journal of Marine Science, 69 (8), 1466-1479.

McCluskie, A.E., Langston, R.H.W. & Wilkinson, N.I. 2013. Birds and Wave & Tidal Stream Energy: An Ecological Review. RSPB Research Report No. 42. Sandy: RSPB.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Murray, S., Wanless, S. & Harris, M.P., 1994. The effects of fixed salmon Salmo salar nets on guillemot Uria aalge and razorbill Alca torda in northeast Scotland in 1992. Biological Conservation. 70, 251–256.

Networks (CHAINSPAN) Steering Group. BTO Report to DEFRA. http://randd.defra.gov.uk/Document.aspx?Document=9962_CHAINSPANFINALREPORT.pdf.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M. L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531–5

Votier, S.C., Birkhead, T.R., Oro, D., Trinder, M., Grantham, M.J., Clark, J.A., McCleery, R.H. & Hatchwell, B.J. 2008. Recruitment and survival of immature seabirds in relation to oil spills and climate variability. Journal of Animal Ecology, 77, 974-983.

Wanless, S., Harris, M.P., Redman, P. & Speakman, J. 2005. Low fish quality as a probable cause of a major seabird breeding failure in the North Sea. Marine Ecology Progress Series, 294, 1-8.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

Common guillemot (non-breeding)

1. Introduction

Common guillemot is a regularly occurring migratory species. Common guillemot (non- breeding) is being considered for inclusion within 2 marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for common guillemot (non-breeding)

2. Species account

Table 1 Summary of status of common guillemot (non-breeding)

Species’ status Score Notes

GB marine Widespread Widespread distribution in the GB marine environment (JNCC range score 89.2%1). The highest distribution densities modelled from boat-based survey data across UK waters were in the Firth of Forth, Moray Firth and over Dogger Bank. Lesser densities were modelled on the east, north and north-west coasts of Scotland, including Orkney, the north-east coast of England and the south-west coasts of England and Wales in the Celtic Sea (Bradbury et al, 2017).

Non-breeding adults tend to remain near their breeding colonies throughout the year, except when moulting in August-September. Few adults move beyond UK waters, although immatures range more widely during the non-breeding season (Furness, 2015). Significance of High Harris & Wanless (2007) suggest 770,000 common guillemots winter in Scottish waters representing Scotland’s seas approximately 28% of the estimated number of birds overwintering in the UK (2,756,526 individuals; in GB context Furness, 2015). However, more recent and comprehensive work by Furness (2015) suggests this is an underestimate. Considering the recent UK distribution maps (Bradbury et al, 2017), which indicate the highest densities of wintering common guillemot occur almost exclusively in Scottish waters and cover relatively large areas, it would seem probable that this is the case. GB contribution High The best available estimate of the UK2 wintering population of this regularly occurring migratory to biogeographic species is 2,756,526 birds (Furness, 2015), which is approximately 67% of the biogeographic population population (with connectivity to UK waters) estimated to be 4,125,000 birds (Furness, 2015). There is high uncertainty around these figures which could range from greater than 50% less to 80% more (Furness, 2015).

Common guillemot have a circumpolar distribution occurring in the low Arctic and boreal waters of the north Atlantic and north Pacific (del Hoyo et al 1996). Breeding birds tend to remain near their colonies

throughout the year and attend nest ledges during winter and the majority of birds in UK waters during the non-breeding season are likely to be from UK colonies (Furness, 2015). European Near The European conservation status for common guillemot is Near Threatened as a result of sharp population Threatened declines in Icelandic populations (BirdLife International, 2015). conservation status The global conservation status is Least Concern (BirdLife International, 2016), which reflects the very large global population size and extensive range, together with an increasing trend in the North American population (ibid). Species’ status summary and The GB common guillemot (non-breeding) population is of high importance to the biogeographic assessment of level of population, with the Scottish wintering population of this regularly occurring migratory species being of representation in Scottish high importance to the overall UK population. This species European population status is considered SPA network Near Threatened, and therefore measures to improve their conservation status are considered to be of moderate importance. Accordingly, the over assessment of the relative importance of Scotland’s marine environment to common guillemot (non-breeding) in Europe is Medium.

This assessment indicates there is an expectation of common guillemot (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of common guillemot (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of common guillemot (non-breeding) (Furness, 2016). These include reports from set net pressures fisheries throughout the species’ range in both the Atlantic and Pacific Oceans of high levels of common guillemot bycatch (see summaries in Tasker et al, 2000 and Žydelis et al, 2013). The large numbers of guillemots drowned in former coastal salmon fisheries off NE Scotland in the 1990s (Murray et al, 1994) were not thought to have been significant at a population level (Bradbury et al, 2017), but similar fisheries elsewhere (e.g. California) have been associated with historic population declines (Atkins & Heneman, 1987). Common guillemot are identified as among the most potentially vulnerable species to bycatch in both surface gears and at depth near the seabed in UK waters given both their susceptibility to entanglement and their distribution at sea in relation to relevant fishing activity (Bradbury et al, 2017), but there is no systematic data from which to assess bycatch rates or impacts (ibid).

Common guillemot (non-breeding) are also susceptible to large scale mortality in major oil spills (Mendel et al, 2008), although impacts on population demographics are complex, with potential for early recruitment to the breeding population to buffer potential population declines (Votier et al, 2008). Guillemots have been identified as showing sensitivity to visual disturbance associated with shipping (Mendel et al, 2008) and displacement from wind farm locations (Furness et al, 2013) and are also potentially sensitive to changes in water clarity associated with activities such as dredging (Cook and Burton, 2010) but the population level impacts are unknown. Similarly, common guillemots have been identified as potentially at relatively high risk of collision with tidal turbines (Furness et al, 2012; McCluskie et al, 2012) but empirical data are lacking.

Changes in sandeel productivity and energy content (Wanless et al, 2005), potentially linked to climate change, have been associated with declines in common guillemot breeding success at colonies in the north and east of the UK3 and breeding populations of common guillemot are predicted to suffer moderate or high magnitude declines in response to climate change over the next 40 years under a medium emissions scenario (Pearce-Higgins et al, 2011). Climate change is also predicted to increase extreme weather and storm events which could result in an increased occurrence of common guillemot wrecks (Harris & Wanless, 2007). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Common guillemot (non-breeding) populations are vulnerable to medium impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by site-based protection.

3. Contribution to Scottish SPA network

This section considers the occurrence of common guillemot (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Common guillemot (non-breeding) is being considered for inclusion at two marine proposed SPAs. There are no existing SPAs for non- breeding common guillemot.

3 http://jncc.defra.gov.uk/page-2898

Table 3 Summary of occurrence of common guillemot (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages and variation

Outer Firth of Supports a non- Common guillemot Provides only Non-breeding adult common guillemots tend to Forth and St breeding seabird (non-breeding) is example on the remain near their breeding colonies throughout Andrews Bay assemblage, including represented within 2 east mainland the year and rarely move beyond UK waters Complex 21,968 common proposed SPAs. coast and (Furness, 2015). As such, non-breeding guillemot4. There are no represents common guillemots in the pSPA are likely to existing SPAs for southern extent of come predominantly from the existing Forth One of the largest and non-breeding the range of this Islands SPA breeding colony. The pSPA is highest density common guillemot. species in also within mean max foraging range of other regular non-breeding No sites were Scotland. important east coast breeding colonies for the aggregations in UK identified in OSPAR species, including Fowlsheugh and St Abb's waters. Region III. There is Head to Fastcastle SPAs. Seas off Foula Supports a non- replication proposed Provides only Non-breeding adult common guillemots tend to breeding seabird within OSPAR example in the remain near their breeding colonies throughout assemblage, including region II. Northern Isles and the year and rarely move beyond UK waters 8,340 common represents the (Furness, 2015). As such, non-breeding guillemot4 northern extent of common guillemots in the pSPA are likely to the range of this come predominantly from the existing Foula species in SPA breeding colony. The pSPA is also within Scotland. mean max foraging range of other Shetland breeding colonies, including Sumburgh Head and Fair Isle SPAs.

4 This is an average number of birds within a site, derived from analysis of densities using the ESAS dataset to identify areas of sea that on average held higher and more aggregated densities of birds than other areas (Kober et al, 2010). Essentially the average figure gives an indication of the relative importance of sites; it represents a snapshot of usage. The total number of individuals using the site will be well in excess of the estimate used for site selection purposes and will reflect turnover within the site.

4. Summary

The proposed Scottish SPA network includes two marine pSPAs for common guillemot (non- breeding), both in OSPAR Region II. Together they support an average of 30,310 birds4. This does not reflect the distribution of common guillemot (non-breeding) in Scotland with notable densities in both OSPAR Regions II and III (Bradbury et al, 2017).

The number and distribution of marine proposed sites for common guillemot (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation indicated by the species assessment (Table 1) in OSPAR Region III.

Further replication in the network would be desirable because common guillemot (non- breeding) are vulnerable to a range of anthropogenic pressures, some of which (e.g. displacement as a result of offshore wind farm developments, collision with tidal turbines) could be managed through provision of site-based protection encompassing supporting habitats (e.g. foraging locations). However, most anthropogenic pressures exist at the wider ecosystem level and are therefore unlikely to be most appropriately managed through site- based protection (e.g. depletion of prey, climate change) (Furness, 2016). Analysis of European Seabirds at Sea (ESAS) data however, found few potentially qualifying hotspots for guillemot in the non-breeding season and none in OSPAR Region III (Kober et al, 2010).

Non-breeding adult common guillemots tend to remain near their breeding colonies throughout the year and rarely move beyond UK waters (Furness, 2015). Likely connectivity between breeding and wintering areas and the two marine pSPAs are collectively within foraging range of at least 6 (of 30) existing colony SPAs (Thaxter et al, 2012). Inclusion of these two pSPAs in the Scottish marine pSPA network potentially provides added conservation value by safeguarding marine habitats supporting prey species used in the non-breeding season by common guillemot (non-breeding) from existing colony SPAs.

5. Conclusion

The number and distribution of marine proposed SPAs for common guillemot (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of common guillemot (non-breeding) in Europe.

Whilst further SPA provision in the network is desirable, the prospect of finding additional SPAs for non-breeding common guillemot is currently unrealistic. There are no known suitable additional SPAs and no other hotspots meeting the population thresholds/regularity requirements for SPA selection were identified for common guillemot (non-breeding) by the (ESAS) analysis. Substantial further work (including survey and/or additional analyses) would be required to identify potentially suitable sites.

Therefore, because common guillemot (non-breeding) are primarily vulnerable to threats and pressures that exist at the wider ecosystem level, significant marine SPA provision is not considered an appropriate conservation measure for common guillemot (non-breeding). However, additional conservation measures are recommended to address anthropogenic threats and pressures influencing common guillemot (non-breeding) populations at the wider seas/ecosystem level.

The case for inclusion of common guillemot (non-breeding) at both marine pSPAs is further supported because of potential functional links with existing colony SPAs.

6. References

Atkins, N. & Heneman, B. 1987. The dangers of gill netting to seabirds. American Birds, 41, (5): 1395-1403.

BirdLife International, 2015. Uria aalge. The IUCN Red List of Threatened Species 2015: e.T22694841A60108623.

BirdLife International, 2016. Uria aalge. The IUCN Red List of Threatened Species 2016: e.T22694841A89505632. http://dx.doi.org/10.2305/IUCN.UK.2016- 3.RLTS.T22694841A89505632.en.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assesssing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

Furness, R.W. 2015. Non-breeding season populations of seabirds in UK waters: Population sizes for Biologically Defined Minimum Population Scales (BDMPS). Natural England Commissioned Reports, 164.

Furness, R.W. 2016. Key pressures and threats faced by marine birds in the UK, conservation action for these birds, and identification of pressures and threats not effectively addressed by existing conservation action. Unpublished report to JNCC. del Hoyo, J., Elliott, A., & Sargatal, J. 1996. Handbook of the Birds of the World, vol. 3: Hoatzin to Auks. Lynx Edicions, Barcelona, Spain.

Harris, M. & Wanless, S. 2007. Common Guillemot. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 2: 845 – 849. Scottish Ornithologists’ Club, Aberlady.

McCluskie, A.E., Langston, R.H.W. & Wilkinson, N.I. 2013. Birds and Wave & Tidal Stream Energy: An Ecological Review. RSPB Research Report No. 42. Sandy: RSPB.

Murray, S., Wanless, S., & Harris, M.P., 1994. The effects of fixed salmon Salmo salar nets on guillemot Uria aalge and razorbill Alca torda in northeast Scotland in 1992. Biological Conservation, 70, 251–256.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M. L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531–5.

Wanless, S., Harris, M.P., Redman, P. & Speakman, J. 2005. Low fish quality as a probable cause of a major seabird breeding failure in the North Sea. Marine Ecology Progress Series, 294, 1-8.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8.

Common gull (non-breeding)

1. Introduction

Common gull is a regularly occurring migratory species. Common gull (non-breeding) is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for common gull (non-breeding)

2. Species account

Table 1 Summary of status of common gull (non-breeding).

Species’ status Score Notes

GB marine Highly Highly restricted distribution in the GB marine environment (JNCC range score 36.1%1). The highest distribution restricted densities modelled from boat-based and aerial survey data across UK waters were along the east coast of England, particularly in the south-east. Lesser densities were modelled along the south and

west coast of England, with pockets of common gull modelled around Scotland in the Firth of Forth, Solway Firth, Moray Firth, around Orkney and along the Western Isles (Bradbury et al, 2017). Kober et al (2010) indicate the Firth of Forth, and the Firth of Clyde are hotspots for common gull (non- breeding) in Scotland. This species forages primarily in terrestrial and intertidal (above mean low water springs) habitats, using marine areas mainly as night-time roosts (Tasker, 2007). Significance of Low Burton et al (2013) estimates 200,296 (185,410 - 215,034) common gulls winter in Scotland Scotland’s seas representing c. 30% of the estimated number of birds overwintering in GB (695,833 individuals; Burton in GB context et al, 20132). GB contribution High The best available estimate of the GB wintering population of this regularly occurring migratory to biogeographic species is 695,833 birds (669,581 - 721,158; Burton et al, 2013), which is approximately 42% of the population biogeographic population (northwest and central Europe) estimated to be 1,640,000 birds (Wetlands International, 2015).

Common gull breed from northern France, the British Isles, Iceland and Scandinavia eastwards across northern Europe to the White Sea in Russia, to north-east Siberia, Alaska and western Canada (Tasker, 2007). The species winters around the North Sea and Atlantic coast of Europe, including a large influx into GB from continental Europe and Iceland, particularly along the east coast (Tasker, 2007, Burton et al, 2013). Post-breeding movements of GB breeders and immatures are limited, mostly within northern Britain and Ireland (Burton et al, 2013).

1 Derived from the distribution models in WWT Consulting (2016) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Data are calculated from counts of birds wintering in terrestrial and near-shore coastal waters; birds roosting offshore or not visible from land are not been included, which therefore may underestimate populations.

European Least The global and European conservation status for common gull is Least Concern (BirdLife population Concern International, 2015 & 2016). conservation status Species’ status summary and The European population status of common gull (non-breeding) is considered Least Concern although assessment of level of GB is of High importance to the very large biogeographic population of this regularly occurring representation in Scottish migratory species. Common gull (non-breeding) have a highly restricted distribution at sea, with the SPA network. highest densities along the east coast of England with lesser densities along the south and west coast of England, in the Firth of Forth, Solway Firth, Moray Firth, Firth of Clyde, around Orkney and along the Western Isles (Kober et al, 2010; Bradbury et al, 2017). This species forages primarily in terrestrial and intertidal (above mean low water springs) habitats, using marine areas mainly as night-time roosts (Tasker, 2007). Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of common gull (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of common gull (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of common gull (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is no evidence of activities in UK waters generating pressures or threats likely to have high or medium impacts threats and on relevant populations of common gull (non-breeding) (Furness, 2016). However, lower level impacts include pressures collision with offshore wind turbines (Furness et al, 2013) and accidental entanglement in fragments of fishing net and other plastic waste (Mendel et al, 2008). Common gull may also be affected by changes to fisheries management aimed at reducing levels of fisheries discards (Bicknell et al, 2013; Bukaciński & Bukacińska, 2003).

The potential impacts of climate change on common gull in the UK are unclear. Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

3. Contribution to Scottish SPA network

This section considers the occurrence of common gull (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Common gull (non-breeding) are being considered for inclusion at two marine proposed SPAs and are represented in one existing colony SPA.

Table 3 Summary of occurrence of common gull (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports a non- Common gull (non-breeding) are Provides only example of this No known linkages. Forth & St breeding seabird represented within 2 proposed species on the east coast of Although post-breeding Andrews Bay assemblage, SPAs and one existing Scotland. movements of GB Complex including common terrestrial SPA in Scotland. breeders and gull equivalent to c. There are no existing SPAs for immatures are limited, 2.1% of the GB this species in this season in mostly within northern non-breeding Scotland. Britain and Ireland population. (Burton et al, 2013). There is no replication of this

feature in the OSPAR regions. Solway Firth Supports a non- Provides only example of this No known linkages. breeding waterbird species on the west coast of Although post-breeding assemblage, Scotland. movements of GB including common breeders and gull with equivalent immatures are limited, to c. 1.8% of the mostly within northern GB non-breeding Britain and Ireland population. (Burton et al, 2013).

4. Summary

This assessment (Table 1) indicates there is an expectation of common gull (non-breeding) being represented once or twice in the Scottish SPA network.

The proposed Scottish SPA network includes two marine pSPAs for common gull (non- breeding) supporting c. 3.9% of the GB non-breeding population2. The pSPAs occur in OSPAR Regions II and III. This species forages primarily in terrestrial and intertidal (above mean low water springs) habitats, using marine areas mainly as night-time roosts (Tasker, 2007).

The number of marine proposed sites for common gull (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the species account (Table 1) but exceeds the minimum level of representation.

Common gull (non-breeding) populations have not been identified as vulnerable to anthropogenic threats or pressures at sea that may have medium or high impacts (Furness, 2016). Threats and pressures at the individual level for which the population level effects are not fully known include collision with offshore wind turbines (Furness et al, 2013), accidental entanglement in fragments of fishing net and other plastic waste (Mendel et al, 2008), and changes to fisheries management aimed at reducing levels of fisheries discards (Bicknell et al, 2013; Bukaciński & Bukacińska, 2003).

There are no known linkages between the one existing terrestrial SPA for this species in Scotland and the pSPAs, although post-breeding movements of GB breeders and immatures are limited to mostly within northern Britain and Ireland (Burton et al, 2013).

5. Conclusion

The number and distribution of marine proposed SPAs for common gull (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of common gull (non-breeding) in Europe.

The marine extension to the Upper Solway Flats and Marshes SPA forming the Solway Firth pSPA will incorporate common gull as a named qualifier of the waterbird assemblage and provides added conservation value by encompassing the full range of intertidal and subtidal habitats used by roosting non-breeding common gull at this location.

No further SPA provision in Scotland's marine environment is considered necessary for common gull (non-breeding).

6. References

Bicknell, A.W.J., Oro, D., Camphuysen, K. & Votier, S.C. 2013. Potential consequences of discard reform for seabird communities. Journal of Applied Ecology, 50, 649–658.

BirdLife International, 2015. Larus canus. The IUCN Red List of Threatened Species 2015: e.T22694308A60081396.

BirdLife International, 2016. Larus canus. The IUCN Red List of Threatened Species 2016: e.T22694308A86717781. http://dx.doi.org/10.2305/IUCN.UK.2016- 3.RLTS.T22694308A86717781.en.

BirdLife International, 2018. Species factsheet: Larus canus. http://www.birdlife.org

Bukaciński, D. & Bukacińska, M. 2003. Larus canus Common Gull. BWP Update, Oxford University Press 5 (1): 13-47.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assesssing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

Kober, K., Webb, A., Win, I., Lewis, M., O'Brien, S, Wilson, L.J. & Reid, J.B., 2010. An analysis of the numbers and distribution of seabirds within the British Fishery Limit aimed at identifying areas that qualify as possible marine SPAs, JNCC Report 431, ISSN 0963-8091.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M. 2007. Mew Gull. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 761 – 766. Scottish Ornithologists’ Club, Aberlady.

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

Common scoter (non-breeding)

1. Introduction

Common scoter is a regularly occurring migratory species. Common scoter (non-breeding) is being considered for inclusion within three marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for common scoter (non-breeding)

2. Species account

Table 1 Summary of status of common scoter (non-breeding)

Species’ status Score Notes

GB marine Widespread There are particular challenges in characterising the distribution of common scoter as they often form distribution very large but patchy flocks in inshore waters some distance from the coast. Analyses of aerial and

boat based surveys (Bradbury et al, 2017; Figure 53) suggests a distribution pattern in inshore waters similar to that indicated by land-based surveys; common scoter were present in c. 47.8% of coastal squares in 2007-11 Atlas (Balmer et al, 2014) and in an average of 26.1% of coastal core WeBS count sectors counted between 2011 and 2015)1. Significance of Low These sources together also highlight several notable concentrations along North Sea coasts Scotland’s seas (including in Moray Firth, Firth of Forth, the Wash and greater Thames) and in the Irish Sea at in GB context Carmarthen Bay and Liverpool Bay, where the population exceeds 55,000 birds (Lawson et al, 2016). Over 50% of the GB wintering population are found in England and Wales. GB contribution Medium The GB wintering population of this regularly occurring migratory species is estimated at 100,000 birds to biogeographic (Musgrove et al, 2013) ) and represents at least 18% of the biogeographic (W Siberia & N population Europe/W Europe & NW Africa) population estimated at 550,000 birds (Wetlands International, 2015 & 2018). However, more recent sources (e.g. Lawson et al, 2015) indicate that the GB wintering population may be considerably greater than currently estimated and there is evidence of recent significant wintering redistribution from the Baltic to the North Sea (BirdLife International, 2017a). The current national and biogeographic wintering population estimates are awaiting systematic review and the relative importance of GB waters to the population wintering in Europe may be greater than previously thought.

Common scoter’s breeding range extends across Iceland, eastern Greenland, Scandinavia and northern parts of western and central Russia with very small numbers in Northern Scotland and western Ireland. The population winters in the Baltic, off Atlantic coasts of Europe and North Africa and in western Mediterranean (BirdLife International, 2017a). The species exhibits complex migratory behaviour between breeding, moulting and wintering grounds, but the GB wintering population is derived mainly from Scandanavian and Icelandic breeding populations (Wernham et al, 2002).

European Low The global and European conservation status for common scoter is Least Concern (Secure) (BirdLife population International, 2017a & b). conservation status Species’ status summary and Common scoter (non-breeding) have a widespread occurrence in GB’s nearshore waters. Within GB, assessment of level of Scotland holds some notable concentrations but the majority of the wintering population occur off the representation in Scottish coasts of England and Wales. The common scoter (non-breeding) population in GB is of medium SPA network. importance to the wintering population of this regularly occurring migratory species in Europe and the. European population status is considered Least Concern (Secure). Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of common scoter (non-breeding) in Europe is Very Low.

This assessment indicates there is no expectation of common scoter (non-breeding) being represented in the Scottish SPA network.

Table 2 Vulnerability of common scoter (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have high and/or medium impacts on relevant populations of common scoter (non-breeding) (Furness, 2016). In particular, common medium threats scoter have been identified as vulnerable to changes in availability of favoured bivalve prey, driven by climate and pressures. change, commercial fisheries, or other environmental pressures (Mendel et al, 2008; Baptist & Leopold, 2009; Hartly, 2007). Common scoter form very large moulting and wintering flocks that are highly vulnerable to chronic oil pollution (Mendel et al, 2008) and spills but there is no evidence of significant long term effects on wintering populations (Banks et al, 2008). Common scoter are highly sensitive to visual disturbance associated with vessel movements (Kaiser et al, 2006; Schwemmer et al, 2011) and also show avoidance of offshore wind farms (Dierschke & Garthe, 2006). Displacement effects may be magnified by reliance on visual cues from conspecifics to find new feeding grounds (McCluskie et al, 2012) and by high energy demands during the flightless moult period (Mendel et al, 2008), but the significance of disturbance and displacement on populations is undocumented. In the Baltic, common scoter are susceptible to drowning in set nets (Mendel et al, 2008). Empirical data on bycatch in British waters are lacking, but common scoter are identified as among the most sensitive species for bycatch at depth near the seabed, with some areas of relatively high potential vulnerability in the winter months encompassing areas with high common scoter densities along North sea coasts (Bradbury et al, 2017). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining

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diversity (SNH, 2016). Marine proposed SPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Common scoter populations are vulnerable to high and medium impacts from a number of different threats and pressures. Representation and replication within the network should be considered.

3. Contribution to Scottish SPA network

This section considers the occurrence of common scoter (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Common scoter (non-breeding) is being considered for inclusion at three marine proposed SPAs and is a feature of the non-breeding waterbird assemblage at two existing estuarine SPAs. One of the marine proposed SPAs is contiguous with the existing SPAs.

Table 3 Summary of occurrence of common scoter (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Moray Firth Supports up to c. Common scoter (non- Provides an example Linkages between wintering and breeding 5.5% of the GB non- breeding) is on the east mainland grounds are presently unknown. However, breeding population. represented within 3 coast and represents the Moray Firth pSPA is the closest proposed SPAs and 2 the northern extent of wintering site to two of the terrestrial SPA

existing the range of this breeding sites (West Inverness-shire Lochs coastal/estuarine species in Scotland and Caithness and Sutherland Peatlands). SPAs.

Common scoter Outer Firth of Supports a non- Provides an example Common scoter (non-breeding) is a feature (breeding) is Forth & St breeding waterfowl on the east mainland of the non-breeding waterbird assemblage represented in 2 Andrews Bay assemblage, coast and represents of the Firth of Forth SPA and Firth of Tay existing terrestrial Complex including common the southern extent of and Eden Estuary SPA, both of which are SPAs. scoter equivalent to the range of this contiguous with this marine proposed SPA. up to c. 4.7% of the Replication of this species in Scotland The common scoter population in this area GB non-breeding feature in the network will use both (intertidal) estuarine and (sub- population. is proposed in tidal) marine environments.

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Proposed SPAs Representation Replication Geographic range Linkages

Solway Firth Supports a non- OSPAR Region II Provides the only Linkages between wintering and breeding breeding waterbird example on the west grounds are presently unknown. However,

assemblage, mainland coast and the Solway Firth pSPA is the closest including common represents the southern wintering site to one of the existing scoter with extent of the range of terrestrial SPA breeding sites (Rhinns of equivalent to up to c. this species in Islay). 1.6% of the GB non- Scotland. breeding population.

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4. Summary

The species assessment (Table 1) indicates there is no expectation of common scoter (non- breeding) being represented in the Scottish SPA network.

The proposed SPA network includes three pSPAs for common scoter (non-breeding) of which two are in OSPAR Region II and one in Region III. Together they support an estimated 11,744 birds, which represents up to 11.7% of the currently documented GB population (Musgrove et al, 2013); although as discussed above (Table 1) this is likely to be considerably underestimated. The proposed SPAs network reflects the full geographic range and variation of common scoter (non-breeding) in Scotland including the major concentrations in east coast Firths and lower densities in the south-west bordering the Irish Sea.

The proposed number and distribution of proposed sites for common scoter (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is higher than the level of representation indicated by the species assessment (Table 1).

However, as outlined above and in Table 1, the majority of wintering common scoter in GB are concentrated at a few locations, within which they form very large flocks, often thousands of birds, associated with the presence of high biomasses of bivalve prey at depths of up to c. 20m (Kaiser et al, 2006; Hartley, 2007; Lawson et al, 2016; Frost et al, 2017). This kind of highly aggregated behaviour at few locations is not explicitly captured by the species assessment as there are no meaningful, referenced metrics on which to base such distinctions. This distribution however means that the GB and European common scoter population as a whole is vulnerable to more localised impacts on major aggregations and there is evidence that such aggregations are vulnerable to a number of threats and pressures, including displacement (e.g. associated with shipping activity) and bycatch in set nets (Kaiser et al, 2006; Mendel et al, 2008). Common scoter’s extreme flocking behaviour and dependence on shallow shellfish beds mean that these threats and pressures can most appropriately be managed through site-based protection of areas used regularly by large aggregations (Furness, 2016).

The Outer Firth of Forth and St Andrews Bay Complex proposed SPA is contiguous with two existing estuarine SPAs. Together these sites provide added conservation value by encompassing the full range of habitats used by common scoter within Scotland’s largest Firth. Potential linkages between marine (and estuarine) sites and three existing terrestrial SPAs for breeding common scoter are unknown.

5. Conclusion

No further SPA provision in Scotland's marine environment is considered necessary for common scoter (non-breeding) however, a review of the level of representation in the Scottish marine proposed SPA network is required by the Advisory Panel.

6. References

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Banks, A.N., Sanderson, W.G., Hughes, B., Cranswick, P.A., Smith, L.E., Whitehead, S., Musgrove, A.J., Havelock, B. & Fairney, N.P. 2008. The Sea Empress oil spill (Wales, UK): Effects on common scoter Melanitta nigra in Carmarthen Bay and status ten years later. Marine Pollution Bulletin, 56, 895-902.

Baptist, M.J. & Leopold, M.F. 2009. The effects of shoreface nourishments on Spisula and scoters in the Netherlands. Marine Environmental Research, 68, 1-11.

BirdLife International, (2017a). Species factsheet: Melanitta nigra. http://www.birdlife.org

BirdLife International, (2017b). European birds of conservation concern: populations, trends and national responsibilities. Staneva, A. & Burfield, I. (comps.). http://www.birdlife.org/europe-and-central-asia/European-birds-of-conservation-concern

Dierschke, V & Garthe, S. 2006. Literature review of offshore windfarms with regards to seabirds. BfN-Skripten, 186, 131-198.

Frost, T.M., Austin, G.E., Calbrade, N.A., Holt, C., Mellan, H.J., Hearn, R.D., Stroud, D.A., Wotton, S.R. & Balmer, D.E.2017. Waterbirds in the UK 2015/16: The Wetland Bird Survey. https://www.bto.org/sites/default/files/wituk-1516-optimised_0.pdf

Hartly, C. 2007. Status and distribution of common scoters on the Solway Firth. British Birds, 100, 280-288.

Kaiser, M. J., Galanidi, M., Showler, D. A., Elliott, J., Caldow, R.W. G., Rees, E. I. S., Stillman, R. A. & Sutherland, W.J. 2006. Distribution and behaviour of common scoter Melanitta nigra relative to prey resources and environmental parameters. Ibis, 148, 110–128.

Lawson, J., Kober, K., Win, I., Allcock, Z., Black, J. Reid, J.B., Way, L. & O’Brien, S.H. 2016. An assessment of the numbers and distribution of wintering waterbirds and seabirds in Liverpool Bay/Bae Lerpwl area of search. JNCC Report No 576. JNCC, Peterborough.

McCluskie, A.E., Langston R.H.W. & Wilkinson N.I. 2012. Birds and wave & tidal stream energy: an ecological review. RSPB Research report No. 42. https://pdfs.semanticscholar.org/9e42/792a8d7e4264e23daaa1bb69523280d3e302.pdf

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Schwemmer, P., Mendel, B., Sonntag, N., Dierschke, V. & Garthe, S. 2011. Effects of ship traffic on seabirds in offshore waters: implications for marine conservation and spatial planning. Ecological Applications, 21, 1851-1860.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds.) 2002. Migration Atlas: movements of birds of Britain and Ireland. Poyser, London

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

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Common tern (breeding)

1. Introduction

Common tern is an Annex 1 species. Common tern (breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for common tern (breeding)

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2. Species account

Table 1 Summary of status of common tern (breeding).

Species’ status Score Notes

GB marine Moderately Breeding common terns forage in inshore waters, typically within c.15 -20km of their colonies distribution restricted (Wilson et al, 2014; Thaxter et al, 2012). This is reflected in the moderately restricted at-sea distribution in UK waters in the summer months, with areas of high density mainly close inshore in the

vicinity of colonies (Bradbury et al, 2017; Mitchell et al, 2004). There is also a high density area off the Yorkshire coast, outwith the foraging range of any major colonies, which is also evident in the late summer distribution as shown in Stone et al (1995). This area may be used by non-breeders or failed breeders. Significance of Low Common terns in GB breed in both coastal and inland colonies but are absent from most of mainland Scotland’s seas Wales and southwest England and are relatively scarce in the Northern Isles and Outer Hebrides in GB context where Arctic terns are more abundant (Mitchell et al, 2004). The Seabird 2000 national census of breeding seabirds in Britain and Ireland found a total GB population of 10,300 pairs of which 4,800 (47%) were in Scotland (Mitchell et al, 2004). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this Annex 1 species is to biogeographic 10,300 pairs which represents 3.0 – 4.7% of the biogeographic population (hirundo subspecies in population Europe) estimated at 220,000 - 340,000 pairs (Mitchell et al, 2004).

Common tern has a circumpolar distribution and can be found breeding in most of Europe, Asia and North America except the extreme north and south. It winters further south, along the coasts and inland South America, along the coast of Africa excluding the north, along parts of the Arabian Peninsula and the whole coast of India, and throughout much of south-east Asia and Australasia (excluding New Zealand) (BirdLife International, 2018). European Least The global and European conservation status for common tern is Least Concern (Secure) (BirdLife population concern International, 2017 & 2018). conservation status Species’ status summary and Breeding common tern in GB are of Medium importance to the biogeographic population of this Annex assessment of level of 1 species and the European population status is considered Least Concern. The distribution of representation in Scottish breeding common terns with GB’s seas is moderately restricted and less than half the population is in

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SPA network. Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of common tern (breeding) in Europe is Very Low.

This assessment indicates there is no expectation of common tern (breeding) being represented in the Scottish SPA network.

Table 2 Vulnerability of common tern (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of common tern (breeding) (Furness, 2016). In particular, common tern populations, including pressures colonies in Scotland, are vulnerable to depletion of food-fish stocks such as sprats and herring, including as a result of commercial fisheries (Jennings et al, 2012; Dänhardt & Becker, 2011). Common tern may be highly sensitive to changes in water turbidity, and birds from colonies in the Firth of Forth may be exposed to relevant activities such as marine aggregate extraction operations, but impacts on populations are undocumented (Cook & Burton, 2010).

Common tern coastal breeding sites are potentially vulnerable to increased flooding associated with storm tides (Mendel et al, 2008) but there is a lack of evidence on potential impacts of climate change on this species. Well- managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Common tern populations are vulnerable to medium impacts from a number of different threats and pressures.

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3. Contribution to Scottish SPA network

This section considers the occurrence of common tern (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Common tern (breeding) is being considered for inclusion at one marine proposed SPA and is a feature at six existing colony SPAs, one of which has a marine extension. The marine proposed SPAs encompass the foraging areas used by breeding terns from existing colony SPAs. The foraging areas used by common terns extend beyond existing marine extensions which are classified to protect areas used by other species for maintenance behaviours close to the colony such as preening, loafing and roosting.

Table 3 Summary of occurrence of common tern (breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports c. 8.8% Common tern (breeding) is Provides only example of this Birds foraging in the Outer Forth and St of the GB breeding represented within one marine species in Scotland. Firth of Forth and St Andrews Bay population. proposed SPA and 6 existing Andrews Bay Complex are

Complex SPAs, one of which has a within foraging range of marine extension. However, breeding colonies at Forth common tern is not the species Islands SPA and Imperial determining the extension. Dock Lock, Leith SPA (Wilson et al, 2014). No sites were identified in OSPAR Region III.

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4. Summary

The species assessment (Table 1) indicates there is no expectation of common tern (breeding) being represented in the Scottish SPA network.

The proposed Scottish SPA network includes one marine proposed SPA for common tern (breeding), in OSPAR Region II.

The number and distribution of marine proposed sites for common tern (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is higher than the level of representation anticipated by the species assessment (Table 1).

There is evidence that common tern populations are vulnerable to depletion of food stocks and foraging birds may be sensitive to changes in water turbidity. In conjunction with wider seas measures to safeguard prey stocks, site-based protection of core marine foraging areas is considered an appropriate conservation measure to enhance resilience of common tern populations to threats and pressures.

The Outer Firth of Forth and St Andrews Bay Complex pSPA is functionally linked to two common tern colony SPAs in the Firth of Forth which together represent the largest concentration (8.8% of GB population) of breeding common terns in Scotland. These colonies and the pSPA are located within an area of high levels of human activity in the marine and coastal environment.

5. Conclusion

No further SPA provision in Scotland's marine environment is considered necessary for common tern (breeding) however; a review of the level of representation in the Scottish marine proposed SPA network is required by the Advisory Panel.

6. References

BirdLife International, 2018. Species factsheet, Sterna hirundo. http://www.birdlife.org

Dänhardt, A. & Becker, P.H. 2011. Herring and sprat abundance indices predict chick growth and reproductive performance of common terns breeding in the Wadden Sea. Ecosystems, 14, 791-803

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Jennings, G., McGlashan, D.J. & Furness, R.W. 2012. Responses to changes in sprat abundance of common tern breeding numbers at 12 colonies in the Firth of Forth, east Scotland. ICES Journal of Marine Science, 69, 572-577.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wilson L. J., Black J., Brewer, M. J., Potts, J. M., Kuepfer, A., Win I., Kober K., Bingham C., Mavor R. & Webb A. 2014. Quantifying usage of the marine environment by terns Sterna sp. around their breeding colony SPAs. JNCC Report No. 500

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European shag (breeding)

1. Introduction

European shag is a regularly occurring migratory species. European shag (breeding) is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for European shag (breeding)

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2. Species assessment

Table 1 Summary of status of European shag (breeding)

Species’ status Score Notes

GB marine Highly European shag (breeding) have a highly restricted distribution in the GB marine environment (present distribution restricted in 33% of 100km squares in GB waters; JNCC derived from Kober et al, 2010) which reflects their dependence on relatively shallow inshore waters over sandy or rocky substrates, typically within 10- 15km of their colonies (Daunt et al, 2015; Thaxter et al, 2012; Bradbury et al, 2017). Significance of High European shags in GB breed in coastal colonies throughout Scotland, including the Northern Isles and Scotland’s seas Outer Hebrides, on the Farne Islands off Northumbria, and in Wales and SW England, but are virtually in GB context absent from eastern, SE and NW England (Mitchell et al, 2004). This is reflected in their marine distribution (Bradbury et al, 2017). The Seabird 2000 national census of breeding seabirds in Britain and Ireland found a total GB population of 27,667 pairs of which 21,487 (78%) were in Scotland (Mitchell et al, 2004). GB contribution High The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 27,667 pairs which represents 39.7 – 43.9% of the biogeographic population population (aristotelis subspecies NE Atlantic) estimated at 66,000 - 73,000 pairs (Mitchell et al, 2004).

European shag are found along the entire Atlantic coast of Europe, as far north as Finland and Iceland, as far south as the coast of Morocco, and around the entire Mediterranean as well as parts of the Black Sea (BirdLife International, 2018). Nearly 90% of shags belong to the aristotelis subspecies which is confined to the Atlantic coasts of Europe (Mitchell et al, 2004) European Declining The European population conservation status is Declining (BirdLife International, 2017). population The global conservation status is Least Concern; this reflects the large size and very extensive range conservation of the population (BirdLife International, 2018). status Species’ status summary and Breeding European shag in GB are of High importance to the biogeographic population of this assessment of level of regularly occurring migratory species and the European population status is considered Declining. representation in Scottish European shag (breeding) have a highly restricted distribution at sea, with the highest densities in SPA network. Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of European shag (breeding) in Europe is Very High.

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Species’ status Score Notes

This assessment indicates there is an expectation of European shag (breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of European shag (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have high or threats and medium impacts on relevant populations of European shag (breeding) (Furness, 2016). Shag species are pressures susceptible to fatal entanglement in fishing gears (including trammel nets, set gill nets, bottom otter trawls and pots/traps) (ICES, 2013) and in southern Europe such mortality has been linked to local population declines (Tasker et al, 2000; Zydelis et al, 2013). European shag are also susceptible to entanglement in netting at fish farms (Bradbury et al, 2017) but the significance of such mortality is unknown. European shag are identified as among the most potentially sensitive species to bycatch in surface gears, pelagic gears and at depth near the seabed in UK waters (Bradbury et al, 2017), but there is no systematic data from which to assess bycatch rates or impacts (ibid).

There is also potential for individual-level impacts on European shag (breeding) through collision with tidal-stream energy generating devices, however potential population-level impacts are currently unknown (Furness et al, 2012).

European shag are susceptible to both direct, in particular increased storminess (Bustnes et al, 2013; Frederiksen et al, 2008), and indirect effects of climate change (e.g. shortages of sandeels associated with increases in sea surface temperature)1. Breeding populations of European shag in the UK are predicted to suffer moderate or high magnitude declines in response to climate change over the next 40 years under a medium emissions scenario (Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

1 http://jncc.defra.gov.uk/page-2877

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European shag (breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of European shag (breeding) within the marine proposed SPAs and existing SPAs in Scotland. European shag (breeding) are being considered for inclusion at two marine proposed SPAs and are represented in 11 existing colony SPAs, all of which have marine extensions classified to protect areas used by various other cliff-nesting seabird species for maintenance behaviours, such as preening, loafing and roosting, close to the colony.

Table 3 Summary of occurrence of European shag (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic Linkages range

Outer Firth of Supports foraging European shag (breeding) Provides only Tracking studies (Daunt et al, 2015) Forth and St shags from the Forth is represented within 2 example in the identified foraging areas within the Outer Andrews Bay Islands SPA, which proposed SPAs and 11 southerly part of Firth of Forth and St Andrews Bay Complex Complex when classified in 1990 existing SPAs, all of which the range of this pSPA used by birds from the Forth Islands held 2400 pairs. The have marine extensions. species on the SPA. Parts of the pSPA are also within average population However, shag is not the east coast of mean foraging range (5.9km; Thaxter et al, between 2007 and species determining the Scotland. 2012) of breeding colonies at St Abbs Head 2011 was 1009 pairs. extension. to Fast castle SPA.

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Proposed SPAs Representation Replication Geographic Linkages range

Moray Firth Supports a breeding Replication of this feature in Provides only Birds foraging in the Moray Firth are within seabird assemblage, the network is proposed in example in the mean foraging range (5.9km; Thaxter et al, including at least 5,494 OSPAR Region II. core part of the 2012) foraging range of the breeding colony European shag2. range of this at East Caithness cliffs SPA. No sites were identified in species on the OSPAR Region III. east coast of Scotland.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of European shag (breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

The proposed Scottish SPA network includes two marine pSPAs for European shag (breeding) that together provide foraging areas for c.7,500-10,000+ birds. Both of these pSPAs are within OSPAR Region II and together they are within mean foraging range (Thaxter et al, 2012) of 3 (of 11) existing colony SPAs. This distribution does not fully reflect that of breeding European shag in Scotland as there are no sites associated with major colonies (e.g. Shiant Isles or Canna and Sanday) in western Scotland (OSPAR Region III) or in Shetland, which in 1998-2002 held 29% of the Scottish population3.

The number and distribution of marine proposed sites for European shag (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation indicated by the species assessment (Table 1).

Inclusion of the Outer Firth of Forth and St Andrews Bay Complex pSPA and Moray Firth pSPA in the network provides added conservation value by encompassing the full range of habitats used by European shag (breeding) in Scotland’s largest firths.

Representation in OSPAR Region III and replication in both OSPAR regions would be desirable given the relative value (Very High) of protected areas in Scotland’s marine environment to conservation of European shag (breeding) and because there is evidence that European shag (breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of European shag (breeding) to such threats and pressures. Site-based protection also promotes resilience to sporadic population “wrecks” that shags are subject to and which may depress breeding populations over a number of subsequent years (Heubeck et al, 2015).

5. Conclusion

The number and distribution of marine proposed SPAs for European shag (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of European shag (breeding) in Europe.

Further SPA provision, particularly representation in OSPAR Region III, or additional site- based and/or alternative conservation measures are recommended for European shag (breeding). Potentially suitable additional SPAs could probably be identified with relatively little additional work.

3 Populations at three major colonies in Shetland have subsequently declined by almost 90%, apparently as a consequence of high mortality associated with prolonged gales in the winters of 2003, 2011 and 2014 (Heubeck et al, 2015).

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6. References

BirdLife International, 2018. Species factsheet, Phalacrocorax aristotelis. http://www.birdlife.org

Bustnes, J.O., Anker-Nilssen, T., Erikstad, K.E., Lorentsen, S.H. & Systad, G.H. 2013. Changes in the Norwegian breeding population of European shag correlate with forage fish and climate. Marine Ecology Progress Series, 489, 235-245.

Daunt, F., Bogdanova, M., McDonald, C. & Wanless, S. 2015. Determining important marine areas used by European shag breeding on the Isle of May that might merit consideration as additional SPAs 2012. JNCC Report No 556. JNCC, Peterborough.

Frederiksen, M., Daunt, F., Harris, M.P. & Wanless, S. 2008. The demographic impact of extreme events: stochastic weather drives survival and population dynamics in a long-lived seabird. Journal of Animal Ecology, 77, (5): 1020-1029.

Heubeck, M., Mellor, R.M., Gear, S. & Miles, W.T.S. 2015. Population and breeding dynamics of European Shags Phalacrocorax aristotelis at three major colonies in Shetland, 2001-15. Seabird, 28, 55-77.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

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SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M.L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531– 547.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

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European shag (non-breeding)

1. Introduction

European shag is a regularly occurring migratory species. European shag (non-breeding) is being considered for inclusion within four marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for European shag (non-breeding)

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2. Species account

Table 1 Summary of status of European shag (non-breeding)

Species’ status Score Notes

GB marine Highly Highly restricted distribution in the GB marine environment (JNCC range score 13.9%1). The highest distribution restricted densities modelled from boat-based survey data across UK waters were along the east coast of Scotland extending around Orkney, the western coast of Scotland and the south-west of England. Lesser densities were modelled along south-west Scotland, west England and Wales (Bradbury et al, 2017). However, data for English waters are limited. Austin et al (2017) and Kober et al (2010) also indicate European shag (non-breeding) distribution around Shetland. Significance of High Austin et al, 2017 estimates that c. 90% of the GB population of European shag in non-estuarine Scotland’s seas coastal waters occur in Scotland, whilst Furness (2015) estimates that approximately 80% of in GB context the UK population occurs in Scotland. Therefore Scotland has a particular responsibility for this species. GB contribution High The estimated GB wintering population of this regularly occurring migratory species used for site to biogeographic selection was 110,000 birds, which is 55% of the biogeographic population (coastal N Europe) population estimated to be 200,000 birds (Wetlands International, 2015). However, breeding birds tend to remain within 50km of their breeding site (Wernham et al, 2002); therefore there are negligible movement of birds into and out of UK waters (Furness, 2015). As such, this recent work by Furness (2015) suggests it is more appropriate to use the UK wintering population estimate of 96,287 birds, which is approximately 90% of a biogeographic population (with connectivity to UK waters) estimated to be 106,000 birds (Furness, 2015).

European shag are found along the entire Atlantic coast of Europe, as far north as Finland and Iceland, as far south as the coast of Morocco, and around the entire Mediterranean. The species breeds along most of the European and north African coastline, as well as parts of the Black Sea (BirdLife International, 2018). Birds wintering in GB waters are likely to be GB breeding birds (Furness, 2015).

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European Declining The European population conservation status is Declining (BirdLife International, 2017). population conservation The global conservation status is Least Concern; this reflects the large size and very extensive range status of the population (BirdLife International, 2017). Species’ status summary and The European shag population wintering in Scotland’s inshore waters has a highly restricted assessment of level of distribution and is of high importance to the wintering population of this regularly occurring migratory representation in Scottish species in both GB and Europe. This species European population status is Declining. Accordingly, SPA network. the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of European shag (non-breeding) in Europe is Very High.

This assessment indicates there is an expectation of European shag (non-breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of European shag (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of European shag (non-breeding) (Furness, 2016); namely impacts from use of static fishing pressures gear (e.g. static nets, fyke nets, lobster pots, seine nets), which result in accidental bycatch and depletion of prey (Tasker et al, 2000; Zydelis et al, 2013; Bradbury et al, 2017). Other lower-level impacts include vulnerability to pollutants (e.g. polyisobutylene) (Camphuysen et al, 2010) and potential impacts of offshore wind farm developments (although there are also potential benefits to this species as a result of range extension) (Furness & Wade, 2012). Visual disturbance as a result of vessel movements may negatively impact foraging behaviour (Cook and Burton, 2010; Velando and Munilla, 2011). There is also potential for individual-level impacts on European shag (non- breeding) through collision with tidal-stream energy generating devices, however potential population-level impacts are currently unknown (Furness et al, 2012).

Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

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European shag (non-breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of European shag (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. European shag (non-breeding) are being considered for inclusion at four marine proposed SPAs. There are no existing SPAs for non-breeding shag.

Table 3 Summary of occurrence of European shag (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

North Orkney Supports c. 1.6% European shag (non-breeding) Provides an example in Non-breeding European shag of the GB non- is represented within 4 proposed the Northern Isles and tend to remain within 50km of breeding SPAs. There are no existing represents the northern their breeding site (Wernham et population. SPAs for non-breeding extent of the range of al, 2002). European shags in Scotland. this species in European shag is a feature of the Scotland. European shag (breeding) is East Caithness Cliffs SPA, which represented in 11 existing is just beyond 50km from this SPAs, all of which have marine proposed marine SPA. extensions. However, shag is Scapa Flow Supports c. 2.9% Provides an example in Non-breeding European shag not the species determining the of the GB non- the Northern Isles and tend to remain within 50km of extension. breeding represents the northern their breeding site (Wernham et population. Replication of this feature in the extent of the range of al, 2002). network is proposed in OSPAR this species in European shag is a feature of the Region II. Scotland. East Caithness Cliffs SPA, which No sites were identified in is within 50km of this proposed OSPAR Region III. marine SPA.

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Proposed SPAs Representation Replication Geographic range Linkages

Moray Firth Supports c. 5.9% Provides an example Non-breeding European shag of the GB non- on the east mainland tend to remain within 50km of breeding coast and represents a their breeding site (Wernham et population. core part of the range al, 2002). of this species in European shag (non-breeding) is Scotland. a feature of the East Caithness Cliffs SPA which overlaps with this proposed marine SPA. Outer Firth of Supports c. 2.2% Provides an example Non-breeding European shag Forth and St of the GB non- on the east mainland tend to remain within 50km of Andrews Bay breeding coast and represents their breeding site (Wernham et Complex population. the southern extent of al, 2002). the range of this European shag (non-breeding) is species in Scotland. a feature of the Forth Islands SPA and St Abbs Head to Fast Castle SPA, both of which are contiguous with this proposed marine SPA.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of European shag (non- breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

The proposed SPA network includes four proposed SPAs for European shag (non-breeding) which together represent c. 13% of the GB non-breeding population, of which 80-90% occur in Scotland (Furness, 2015; Austin et al, 2017). There is replication within OSPAR Region II, but no sites are proposed in OSPAR Region III. This does not reflect either the full geographic range, which extends along both the east and west coasts and around Orkney (Bradbury et al, 2017), or the varied environments in which shags occur, which include both sheltered waters and exposed Atlantic and North Sea coasts. Austin et al, 2017 also indicate numerous observations of European shag (non-breeding) around Shetland.

The proposed number and distribution of proposed sites for European shag (non-breeding) in the Scottish pSPA network as summarised above and Table 3 is below the minimum level indicated by the species assessment (Table 1).

Representation in OSPAR Region III and replication in both OSPAR regions II and III would be desirable because there is evidence that European shag (non-breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of European shag (non-breeding) to such threats and pressures.

Within Orkney in OSPAR Region II, there are two pSPAs for European shag (non-breeding); at North Orkney and Scapa Flow. These sites represent the northern part of the range of this species in Scotland and together support up to 4.5% of the GB population. Scapa Flow pSPA holds the second largest number of European shag (non-breeding) in the Scottish pSPA suite and North Orkney the 4th largest.

The Outer Firth of Forth and St Andrews Bay Complex pSPA is contiguous with two existing coastal SPAs for which non-breeding European shag is a feature, Scapa Flow pSPA and Moray Firth pSPA either overlap with, or are within wintering range of one other existing coastal SPA for which breeding European shag is a feature.

5. Conclusion

The number and distribution of marine proposed SPAs for European shag (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of European shag (non-breeding) in Europe.

The case for inclusion of European shag (non-breeding) in the Outer Firth of Forth and St Andrews Bay Complex pSPA, Scapa Flow pSPA and Moray Firth pSPA is further supported because they are functionally linked to existing SPAs.

Further SPA provision, particularly representation in OSPAR Region III, or additional site- based and/or alternative conservation measures are recommended European shag (non- breeding). Potentially suitable additional SPAs could probably be identified with relatively little additional work.

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A review of the level of local geographical replication in the Northern Isles is required by the Advisory Panel.

6. References

BirdLife International, 2018. Species factsheet, Phalacrocorax aristotelis. http://www.birdlife.org

Camphuysen, C.J., Schouten, S. & Gronert, A. 2010. Mystery spill of Polyisobutylene (C4H8) off the Dutch coast affecting seabirds in March 2010. Seabird, 23, 143-145.

Furness, R. & Wade, H. 2012. Vulnerability of Scottish seabirds to offshore wind turbines. Report commissioned by Marine Scotland.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M.L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531– 547.

Velando, A. & Munilla, I. 2011. Disturbance to a foraging seabird by sea-based tourism: Implications for reserve management in marine protected areas. Biological Conservation, 144, 1167–1174.

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Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds.) 2002. Migration Atlas: movements of birds of Britain and Ireland. Poyser, London.

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

Zydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries. A global review. Biological Conservation, 162, 76-88.

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European storm-petrel (breeding)

1. Introduction

European storm-petrel is an Annex 1 species. European storm-petrel (breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for European storm-petrel (breeding)

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2. Species account

Table 1 Summary of status of European storm-petrel (breeding).

Species’ status Score Notes

GB marine Widespread European storm-petrel (breeding) have a widespread distribution in the GB marine environment distribution (JNCC range score 91.7%1). Modelling of boat-based and aerial survey data across UK waters

shows generally low densities in nearshore waters with areas of much higher density further offshore, in particular along the shelf break to the north-west of Scotland, to the south of the Outer Hebrides, and in the western approaches to Cornwall and the isles of Scilly (Bradbury et al, 2017; Stone et al, 1995). Significance of High The distribution of European storm-petrel in GB seas reflects the northerly and westerly breeding Scotland’s seas distribution in GB with 83% of breeding birds in Scotland and the largest colonies (>1000 pairs) at in GB context Mousa (Shetland), Treshnish Isles (Argyll and Bute), Priest Island (Wester Ross) and St Kilda (Mitchell et al, 2004). Elsewhere in GB there are substantial colonies on the Isles of Scilly and at Skomer and Skokholm in Wales (ibid). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this Annex 1 species is to biogeographic 25,710 pairs, equivalent to 3.1 – 11.3% of the biogeographic population (pelagicus northeastern population Atlantic) estimated at 300,000 – 680,000 pairs (Mitchell et al, 2004).

European storm-petrel breeding grounds are concentrated in remote islands on Atlantic coasts of the Faroe Islands, Ireland, and Iceland with smaller colonies in France, Norway, Spain and the Canary Islands; much smaller numbers (melitensis subspecies) are found in the Mediterranean (BirdLife International 2018; Mitchell et al, 2004). The species winters off western and southern Africa. European Least The European and global conservation status of European storm-petrel is Least Concern (Secure) population Concern (BirdLife International, 2017 & 2018). conservation status

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Species’ status summary and The European population status of breeding European storm-petrel is considered Least Concern and assessment of level of GB is of Medium importance to the biogeographic population of this Annex 1 species. European representation in Scottish storm-petrel (breeding) have a widespread distribution at sea, with the highest densities to the north SPA network. and northwest of Scotland where the majority of the GB breeding population is located. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of European storm-petrel (breeding) in Europe is Low.

This assessment indicates there is an expectation of European storm-petrel (breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of European storm-petrel (breeding) populations to anthropogenic threats and pressures.

Vulnerability to European storm-petrels are highly vulnerable to depredation by introduced mammalian predators at their breeding threats and colonies, but when at sea there is no specifically documented evidence of activities in UK waters generating pressures pressures or threats likely to have either high or medium impacts on relevant populations (Furness, 2016).

There are recorded incidences of storm-petrel entanglement in fishing gear, most likely during hauling (Žydelis et al, 2013) but the sensitivity of European storm-petrel to potential bycatch in fisheries operating in UK waters is judged to be low (Bradbury et al, 2017).

The potential impacts of climate change on European storm-petrel in the UK are unclear (Pearce-Higgins et al, 2011) although one model suggests that they may increase their European range size providing they can successfully disperse and suitable breeding and foraging habitat is available (Russell et al, 2015) Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

European storm petrel (breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by marine site-based protection.

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3. Contribution to Scottish SPA network

This section considers the occurrence of European storm-petrel (breeding) within the marine proposed SPAs and existing SPAs in Scotland. European storm-petrel (breeding) are being considered for inclusion at one marine proposed SPA and are represented in seven existing colony SPAs, three of which have marine extensions, although not specifically for this species.

Table 3 Summary of occurrence of European storm-petrel (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Seas off St Kilda Supports a European storm-petrel is Provides only example of Birds foraging in the Seas off breeding seabird represented within one this species in Scotland. St Kilda are within foraging

assemblage, proposed SPA and 7 existing range of the breeding colony

including 954 colony SPAs, three of which at St Kilda SPA. There is European storm- have marine extensions. little information on foraging petrel2. ranges of European storm- However, storm-petrel is not the petrel (Thaxter et al, 2012) so species determining the potential linkages to extension. additional colonies are No sites were identified in unknown. OSPAR Region II.

2 This is an average number of birds within a site, derived from analysis of densities using the ESAS dataset to identify areas of sea that on average held higher and more aggregated densities of birds than other areas (Kober et al, 2010). Essentially the average figure gives an indication of the relative importance of sites, it represents a snapshot of usage because the entire population of the relevant breeding colonies are not at sea at any one time and are not solely confined to those areas identified as pSPAs. The total number of individuals using the site over the breeding season will be well in excess of the estimate used for site selection purposes and will reflect the breeding populations at colonies within foraging range of the site and turnover within the site.

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4. Summary

This assessment indicates there is an expectation of European storm-petrel (breeding) being represented once or twice in the Scottish SPA network.

The proposed Scottish SPA network includes one marine pSPA for European storm-petrel (breeding) holding an average of 954 birds2. This pSPA is mainly in OSPAR region III, with a small part of the site in OSPAR Region V, and is within the area to the northwest of Scotland identified as holding some of the highest summer densities of European storm-petrel in Scotland’s seas (Bradbury et al, 2017). No sites have been identified in OSPAR Region II, particularly in the vicinity of Shetland, which holds over a third of the Scottish population and the largest single colony in GB (Mitchel et al, 2004).

The number of marine proposed sites for European storm-petrel (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the level of representation anticipated by the species assessment (Table 1).

Replication in the network is desirable because of the Annex 1 status of European storm- petrel. Storm-petrel (breeding) populations however, have not been identified as vulnerable to anthropogenic threats or pressures at sea and may also be relatively resilient to climate change (Furness, 2016; Russell et al, 2015). The most significant threats identified are introduction of mammalian predators to breeding colonies (Furness, 2016) and the largest of these colonies in Scotland are already designated as (terrestrial) SPAs.

Inclusion of European storm petrel (breeding) in the Seas off St Kilda pSPA provides added conservation value to the Scottish marine SPA network by safeguarding the foraging habitats and prey species used by European storm petrel (breeding) from the existing colony SPA(s).

European storm-petrel are surface feeders with a wide-ranging, dispersed and unpredictable marine distribution, which limits potential for identification of regularly occurring hotspots of activity at sea (Kober et al, 2010 & 2012).

5. Conclusion

The number and distribution of marine proposed SPAs for European storm-petrel (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of European storm-petrel (breeding) in Europe.

The case for inclusion of European storm petrel (breeding) at the Seas off St Kilda pSPA is further supported because it is functionally linked to existing colony SPA(s).

Additional marine SPA provision is not considered an appropriate conservation measure for European storm petrel (breeding) due to the widely dispersed and unpredictable nature of their distribution. However, alternative conservation measures could be considered to address anthropogenic threats and pressures influencing European storm petrel (breeding) populations at the wider seas/ecosystem level.

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6. References

BirdLife International, 2018. Species factsheet, Hydrobates pelagicus. http://www.birdlife.org

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

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Goosander (non-breeding)

1. Introduction

Goosander is a regularly occurring migratory species. Goosander (non-breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for goosander (non-breeding)

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2. Species account

Table 1 Summary of status of goosander (non-breeding).

Species’ status Score Notes

GB marine Widespread Goosander (non-breeding) winter predominantly in freshwater habitats, including rivers, throughout GB distribution with the exception of upland areas of northern Scotland and parts of southern and eastern England

(Balmer et al, 2014). They were recorded in 73.1% of inland squares surveyed in winter for the 2007-11 Atlas and in 55% of coastal squares1. Goosander were recorded in an average of 33.0% of all c.2700 (coastal and freshwater) core WeBS count sectors counted between 2011 and 2015 and in an average of 25.8% of c. 400 coastal sectors2. Significance of High With the exception of a single site in Wales, the most consistently important coastal WeBS count Scotland’s seas sectors for goosander in the UK are in Scotland or Scottish/English border counties, including in GB context the Solway Firth, Tweed Estuary, Berwick Coast and Firths of Forth and Tay (Frost et al, 2017). Hence Scotland has a particular responsibility for goosander wintering in the coastal waters of GB. GB contribution Medium The GB wintering population (freshwater and coastal) of this regularly occurring migratory species is to biogeographic 12,000 birds (Musgrove et al, 2013), which is 4.5% of the biogeographic population (merganser population sub-species, North-west & Central Europe (win)) estimated at 266,000 birds (Wetlands International, 2015 & 2018).

Goosander can be found breeding year-round in more temperate parts of their circumpolar breeding range, which in Europe includes France, Germany, the majority of Scandinavia and Russia, the United Kingdom and Iceland. Northern breeding populations are fully migratory but breeders in temperate regions are sedentary or only travel short distances (BirdLife International, 2018). Those that winter in Britain are thought to be largely derived from the British breeding population (3,500 pairs; Musgrove et al, 2013) but some may migrate from the near continent, especially to southeast England, during periods of cold weather. Males from British breeding populations migrate to Norway returning to Britain between November and January but most females and juveniles are considered to remain in Britain throughout the year (Wright et al, 2012).

1 Data supplied on 14 February 2018 by the British Trust for Ornithology 2 Data supplied on 14 February 2018 by the British Trust for Ornithology, the Royal Society for the Protection of Birds and the Joint Nature Conservation Committee (the last on behalf of the statutory nature conservation bodies: Natural England, Natural Resources Wales and Scottish Natural Heritage and the Department of Agriculture, Environment and Rural Affairs, Northern Ireland) in association with the Wildfowl and Wetlands Trust 135

European Least The global and European conservation status of goosander is Least Concern (Secure) (BirdLife population Concern International, 2017 & 2018). conservation status Species’ status summary and Goosander (non-breeding) have a Widespread distribution in both fresh and coastal waters in GB with assessment of level of Scotland being of particular importance to coastal populations. GB is of Medium importance to the representation in Scottish biogeographic population of this regularly occurring migratory species and the European population SPA network. status is considered Least Concern. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of goosander (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of goosander (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of goosander (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is no specifically documented evidence of activities likely to occur in UK coastal waters generating pressures threats and or threats likely to have either high or medium impacts on relevant populations of goosander (non-breeding) pressures (Furness, 2016). Goosander have been reported as bycatch in set net fisheries in the Baltic (ICES, 2013), but there is no evidence of population level impacts.

Goosanders wintering in the UK have been assessed as vulnerable to moderate magnitude declines driven by climate change (Pearce-Higgins et al, 2011.) Significant north-easterly shifts in the wintering range of goosander in NW Europe over the past three decades are attributed to climate change and correlate with an increase of 3.8 °C in early winter temperature in the north-eastern part of the wintering areas (Lehikoinen et al, 2013). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

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3. Contribution to Scottish SPA network

This section considers the occurrence of goosander (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Goosander (non-breeding) is being considered for inclusion at one marine proposed SPA and is a feature of two existing estuarine SPAs and one freshwater SPA.

Table 3 Summary of occurrence of goosander (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Solway Firth Supports a non- Goosander (non-breeding) is Provides the only Goosander (non-breeding) is not a breeding waterbird represented within one example of this qualifying feature of the adjacent assemblage, proposed SPA, two existing species in Scotland. Upper Solway Flats and Marshes including estuarine SPAs and one SPA but is named in the citation as goosander freshwater SPA for this species “notable”. equivalent to c. in Scotland. 1.2% of the GB non-breeding No sites were identified in population. OSPAR Region II.

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4. Summary

This assessment (Table 1) indicates there is an expectation of goosander (non-breeding) being represented once or twice in the Scottish SPA network.

The Scottish pSPA network includes one marine proposed SPA for goosander (non- breeding) in OSPAR Region III. The marine proposed SPA supports up to 1.2% of the GB non-breeding population. This does not reflect the full geographic range and variation of goosander (non-breeding) in Scotland’s coastal waters as there are no sites on the east coast, in OSPAR Region II. However, two existing estuarine/coastal SPAs on the east coast together support c.4.5% of the GB population of goosander (non-breeding), which is a predominantly freshwater species.

The number and distribution of marine proposed sites for goosander (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the level of representation anticipated by the species account (Table 1).

Very few goosander are associated with the non-estuarine coasts of Scotland. The marine extension to the Upper Solway Flats and Marshes SPA forming the Solway Firth pSPA will incorporate goosander as a named qualifier of the waterbird assemblage. This existing estuarine SPA lies within the core range for this species in Scotland on the west coast. Therefore, the existing representation of goosander within the SPA network in Scotland is considered appropriate to the importance of Scotland to both population and range of this species within GB.

5. Conclusion

The number and distribution of marine proposed SPAs for goosander (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of goosander (non-breeding) in Europe.

No further SPA provision in Scotland's marine environment is considered necessary for goosander (non-breeding).

6. References

BirdLife International, 2018. Species factsheet, Mergus merganser. http://www.birdlife.org

Frost, T.M., Austin, G.E., Calbrade, Mellan, H.J., Hearn, R.D., Stroud, D.A., Wotton, S.R. & Balmer, D.E. 2017. Waterbirds in the UK 2015/16: The Wetland Bird Survey. BTO/RSPB/JNCC. Thetford. http://www.bto.org/volunteer-surveys/webs/publications/webs- annual-report

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ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

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Great black-backed gull (breeding)

1. Introduction

Great black-backed gull (breeding) is a regularly occurring migratory species. No marine proposed SPAs have been identified for great black- backed gull (breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of great black-backed gull (breeding)

Species’ status Score Notes

GB marine Partially Great black-backed gull (breeding) have a partially restricted distribution in the GB marine distribution restricted environment (JNCC range score 82.9%1). Modelling of boat-based and aerial survey data across UK waters shows that in the breeding season densities of great black-backed gull in GB are generally greater around Scotland than England, with very low densities in the Irish Sea. However, within this, overall picture there are areas of notably higher densities, in particular off the east coast of England north of the Humber, in the Moray Firth, in the northern Minch and close to the Isles of Scilly (Bradbury et al, 2017). Significance of High In 1999-2002, breeding great black-backed gull in the GB were concentrated in Scotland, which held Scotland’s seas 87.0% of the GB breeding population, with the largest numbers in the Northern Isles and Outer and in GB context Inner Hebrides (Mitchell et al, 2004). Subsequent population trends at a GB level are unclear, but there have been major declines in Scotland2 and apparent increases along the North Sea coast of England (Nager & O'Hanlon, 2016). GB contribution Medium The most recent (1999-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 17,000 pairs, equivalent to 16.8 – 17.0% of the biogeographic population population (Europe, excluding Russia) estimated at 100,000 – 110,000 pairs (Mitchell et al, 2004).

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Globally, great black-backed gull breed in the extreme north-west of Russia, in Scandinavia including Baltic Sea coasts, north-western France, GB and Ireland, Iceland, southern Greenland and Atlantic coasts of Canada and the U.S.A (BirdLife International, 2018), with the European population representing c. 60% of the total (Mitchell et al, 2004). European Least The European and global conservation status of great black-blacked gull is Least Concern ((BirdLife population Concern International, 2017 & 2018). conservation status Species’ status summary and Great black-blacked gull (breeding) in GB are of Medium importance to the biogeographic population assessment of level of of this regularly occurring migratory species and the European population status is considered Least representation in Scottish Concern. Great black-blacked gull (breeding) have a Partially Restricted distribution in GB waters with SPA network. the majority of the population in Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of great black-backed gull (breeding) is Medium.

This assessment indicates there is an expectation of great black-backed gull (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of great black-backed gull (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have either threats and high or medium impacts on relevant populations of great black-backed gull (Furness, 2016). In particular, great pressures black-backed gulls are among the seabird species assessed as most at risk of collision with offshore wind turbines (Furness et al, 2013; Johnston et al, 2014). Great black-backed gull populations are also potentially vulnerable to reductions in availability of fisheries discards (Dunn, 1997; Furness et al, 1992; Hüppop & Wurm, 2000). The species exhibits considerable plasticity in diet and hence may be more adaptable and resilient than some other gulls to changing fisheries practices43, although at some colonies indirect impacts of reduced discard availability could include increased depredation of gull chicks or kleptoparistism by great skuas (Mitchell et al, 2004). There are recorded incidences of gull entanglement in fishing gear, most likely during hauling (Žydelis et al, 2013) and gull species are classed susceptible to bycatch in various fisheries (ICES, 2013). Great black-backed gull are included in the top 50% of species in respect of potential population sensitivity to entanglement in surface gears in UK waters (Bradbury et al, 2017) but there is no systematic data on actual levels of bycatch (ibid).

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Great black-backed gull populations in the UK have been predicted to undergo a large decline in response to climate change (Pearce-Higgins et al, 2011) and range in Europe is predicted to shrink by at least 25% (Russell et al, 2015). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Great black-backed gull (breeding) populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

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3. Summary

The species assessment (Table 1) indicates there is an expectation of great black-backed gull (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

No marine proposed SPAs have been identified for great black-blacked gull (breeding) in the Scottish pSPA network. Great black-blacked gull (breeding) are represented in five existing colony SPAs, four in OSPAR Region II and one in OSPAR Region III. All of these have 2km marine extensions for maintenance behaviours, but great black-blacked gull was not the species driving these extensions.

The number and distribution of marine proposed sites for great black-blacked gull (breeding) in the Scottish pSPA network as summarised above is below the minimum level of representation indicated by the species assessment (Table 1).

Great black-blacked gull are opportunistic omnivores feeding on adult and young birds, birds eggs, fisheries discards, mammals (e.g. rabbits), insects, marine invertebrates (e.g. molluscs), carrion and refuse (Birdlife International 2018; JNCC2). Hence their (direct) reliance on the marine environment is limited and associated with commercial fishing activity (Furness et al, 1992; Wilhelm et al, 2016).

Representation in the Scottish marine pSPA network would be desirable given the relative value of protected areas in Scotland to the conservation of great black-backed gull (breeding) in Europe. Great black-backed gull populations are also potentially vulnerable to a number of threats and pressures associated with human activity in the marine environment. However, analyses of the European Seabirds at Sea (ESAS) database undertaken to support site selection did not detect any great black-backed gull (breeding) hotspots that satisfied both population and regularity site-selection criteria to support inclusion in the Scottish pSPA suite (Kober et al, 2010) and there is no realistic prospect that sites could be identified.

4. Conclusion

There is limited prospect of identifying marine SPAs great black-backed gull (breeding). In addition they are primarily vulnerable to threats and pressures that exist at the wider ecosystem level (and terrestrial environment) which are judged not to be most appropriately managed through marine site-based protection.

SPA provision is therefore not considered appropriate for great black-backed gull (breeding) however, additional and/or alternative conservation measures are recommended to address anthropogenic threats and pressures influencing great black-backed gull (breeding) populations at the wider seas/ecosystem level.

5. References

BirdLife International, 2018. Species factsheet, Larus marinus. http://www.birdlife.org

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Dunn, E. 1997. Sustainable fisheries and seabirds. RSPB Conservation Review, 11, 44-50

Furness, R.W., Ensor, K. & Hudson, A.V. (1992). The use of fishery waste by gull populations around the British Isles. Ardea, 80, 105-113

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

Hüppop, O. & Wurm, S. 2000. Effects of winter fishery activities on resting numbers, food and body condition of large gulls Larus argentatus and L. marinus in the south-eastern North Sea. Marine Ecology Progress Series, 194, 241-247.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Johnston, A., Cook, A.S.C.P., Wright, L.J., Humphreys, E.M. & Burton, N.H.K. (2014) Modelling flight heights of marine birds to more accurately assess collision risk with offshore wind turbines. Journal of Applied Ecology 51(1), 31-41

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Nager, R.G. and O'Hanlon, N.J.2016. Changing Numbers of Three Gull Species in the British Isles Waterbirds, 39, (Special Publication 1): 15-28. https://doi.org/10.1675/063.039.sp108

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wilhelm, S.I., Rail, J.-F., Regular, P.M., Gjerdrum, C. & Robertson, G.J. 2016. Large-scale changes in abundance of breeding Herring Gulls (Larus argentatus) and Great Black-backed

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Gulls (Larus marinus) relative to reduced fishing activities in southeastern Canada. Waterbirds, 39, (sp1): 136-142.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8.

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Great black-backed gull (non-breeding)

1. Introduction

Great black-backed gull (non-breeding) is a regularly occurring migratory species. No marine proposed SPAs have been identified for great black-backed gull (non-breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of great black-backed gull (non-breeding)

Species’ status Score Notes

GB marine Widespread Widespread distribution in the GB marine environment (JNCC range score 91.9%1). The highest distribution densities modelled from boat-based and aerial survey data across UK waters were in the Moray Firth,

the north coast of Scotland, the south and south-east of England, and off Hornsea on the east coast of England (Bradbury et al, 2017). This largely correlates with areas identified by Kober et al (2010), with the addition of a hotspot around St Kilda and along the north-east coast of England, and high densities around Orkney and Shetland. Significance of Low Burton et al (2013)2 estimate 18,113 (16,751 – 19,653) great black-backed gulls winter in Scotland Scotland’s seas representing c. 13% of the best available estimate of birds overwintering in the UK3 (143,521 in GB context individuals; Furness, 2015).

Using the Burton et al (2013) estimate of 75,860 (71,209 – 80,704) individuals wintering in GB, c. 24% of the GB population winter in Scotland. GB contribution High The best available estimate of the UK wintering population of this regularly occurring migratory species to biogeographic is 143,521 (Furness, 2015), which is approximately 61% of the biogeographic population (with

1 Derived from the distribution models in Bradbury et al (2017) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Data are calculated from counts of birds wintering in terrestrial and near-shore coastal waters; birds roosting offshore or not visible from land are not been included, which therefore may underestimate populations. 3 Furness (2015) provides UK reference populations rather than at a GB scale. Figures include consideration of counts of birds at sea, as well as roosting or near to shore observations.

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population connectivity to UK waters) estimated to be 235,000 birds (Furness, 2015). There is moderate uncertainty associated with the Furness (2015) figures, which are likely to be no more than 50% less or 80% greater. A measure of uncertainty is indicated in the range associated with the Burton et al (2013) estimates.

Great black-backed gull breed on coasts from the extreme north-west of Russia, along Scandinavia, on Baltic Sea coasts, on the coasts of north-western France, the United Kingdom and Ireland, across the north Atlantic in Iceland and southern Greenland and on the Atlantic coasts of Canada and the U.S.A. down to North Carolina. Individuals breeding in harsher environments will migrate south, wintering on northern coasts of Europe from the Baltic Sea to southern Portugal, and down North America as far south as the Caribbean (del Hoyo et al, 1996). European Least The global and European conservation status for great black-backed gull is Least Concern (BirdLife population Concern International, 2015 & 2016). conservation status Species’ status summary and The European population status of great black-backed gull (non-breeding) is considered Least assessment of level of Concern although GB is of High importance to the biogeographic population of this regularly occurring representation in Scottish migratory species. Great black-backed gull (non-breeding) have a widespread distribution at sea, with SPA network. the highest densities in the Moray Firth, the north coast of Scotland, the south and south-east of England, and off Hornsea on the east coast of England (Bradbury et al, 2017). This largely correlates with areas identified by Kober et al (2010), with the addition of a hotspot around St Kilda and along the north-east coast of England, and high densities around Orkney and Shetland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of great black-backed gull (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of great black-backed gull (non-breeding) being represented once or twice in the Scottish SPA network.

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Table 2 Vulnerability of great black-backed gull (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have either threats and high or medium impacts on relevant populations of great black-backed gull (Furness, 2016). In particular, great pressures black-backed gulls are among the seabird species assessed as most at risk of collision with offshore wind turbines (Furness et al, 2013; Johnston et al, 2014). Great black-backed gull populations are also potentially vulnerable to reductions in availability of fisheries discards (Dunn, 1997; Furness et al, 1992; Hüppop & Wurm, 2000). The species exhibits considerable plasticity in diet and hence may be more adaptable and resilient than some other gulls to changing fisheries practices4. Great black-backed gull are also vulnerable to coastal oil spills and other types of surface water pollution (BirdLife International, 2015) and to contracting botulism at landfill sites (Lloyd et al,1991).

There are recorded incidences of gull entanglement in fishing gear, most likely during hauling (Žydelis et al, 2013) and gull species are classed susceptible to bycatch in various fisheries (ICES, 2013). Great black-backed gull are included in the top 50% of species in respect of potential population sensitivity to entanglement in surface gears in UK waters (Bradbury et al, 2017) but there is no systematic data on actual levels of bycatch (ibid).

Great black-backed gull (non-breeding) populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions should be considered.

4 http://jncc.defra.gov.uk/page-2888

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3. Summary

The species assessment (Table 1) indicates there is an expectation of great black-backed gull (non-breeding) being represented once or twice in the Scottish SPA network.

No marine proposed SPAs have been identified for great black-blacked gull (non-breeding) in the Scottish pSPA network.

The number and distribution of marine proposed sites for great black-blacked gull (non- breeding) in the Scottish pSPA network is below the minimum level of representation indicated by the species assessment (Table 1).

Great black-blacked gull are opportunistic omnivores feeding on adult and young birds, birds eggs, fisheries discards, mammals (e.g. rabbits), insects, marine invertebrates (e.g. molluscs), carrion and refuse (Birdlife International 2018; JNCC4). Hence their (direct) reliance on the marine environment is limited and associated with commercial fishing activity (Furness et al, 1992; Wilhelm et al, 2016).

Great black-backed gull (non-breeding) are vulnerable to a range of anthropogenic pressures, most of which exist at the wider ecosystem level and are therefore unlikely to be most appropriately managed through site-based protection (e.g. reduction of fishery discards) (Furness, 2016). However, some anthropogenic pressures (e.g. collision as a result of offshore wind farm developments) could be managed through provision of site- based protection encompassing supporting habitats (e.g. foraging locations). Analysis of ESAS data did not detect any great black-backed gull (non-breeding) hotspots that satisfied both population and regularity site-selection criteria to support inclusion in the Scottish pSPA suite (Kober et al, 2010).

4. Conclusion

There is limited prospect of identifying marine SPAs great black-backed gull (non-breeding). In addition they are primarily vulnerable to threats and pressures that exist at the wider ecosystem level (and terrestrial environment) which are judged not to be most appropriately managed through marine site-based protection.

SPA provision is therefore not considered appropriate for great black-backed gull (non- breeding) however, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing great black-backed gull (non- breeding) populations at the wider seas/ecosystem level.

5. References

BirdLife International, 2015. Larus marinus. The IUCN Red List of Threatened Species 2015: e.T22694324A60082963. .

BirdLife International, 2016. Larus marinus. The IUCN Red List of Threatened Species 2016: e.T22694324A86733265. http://dx.doi.org/10.2305/IUCN.UK.2016- 3.RLTS.T22694324A86733265.en.

BirdLife International, 2018. Species factsheet: Larus marinus. http://www.birdlife.org

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Dunn, E. 1997. Sustainable fisheries and seabirds. RSPB Conservation Review, 11, 44-50. del Hoyo, J., Elliott, A., & Sargatal, J. 1996. Handbook of the Birds of the World, vol. 3: Hoatzin to Auks. Lynx Edicions, Barcelona, Spain.

Furness, R.W., Ensor, K. & Hudson, A.V. (1992). The use of fishery waste by gull populations around the British Isles. Ardea, 80, 105-113.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Lloyd, C., Tasker, M.L. & Partridge, K. 1991. The Status of Seabirds in Britain and Ireland. Poyser, London.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Nager, R.G. and O'Hanlon, N.J.2016. Changing Numbers of Three Gull Species in the British Isles Waterbirds, 39, (Special Publication 1): 15-28.

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SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wilhelm, S.I., Rail, J.-F., Regular, P.M., Gjerdrum, C. & Robertson, G.J. 2016. Large-scale changes in abundance of breeding Herring Gulls (Larus argentatus) and Great Black-backed Gulls (Larus marinus) relative to reduced fishing activities in southeastern Canada. Waterbirds, 39 (sp1): 136-142.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8.

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Great cormorant (breeding)

1. Introduction

Great cormorant (breeding) is a regularly occurring migratory species. No marine proposed SPAs have been identified for great cormorant (breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of great cormorant (breeding)

Species’ status Score Notes

GB marine Highly Great cormorant (breeding) have a highly restricted distribution in the GB marine environment (JNCC distribution restricted range score 11.3%1). Modelling of boat-based and aerial survey data across UK waters shows that in the breeding season great cormorant in GB are largely confined to coastal waters, with the greatest densities observed in Liverpool Bay and Moray Firth (Bradbury et al, 2017). Significance of Moderate Great cormorant (breeding) feed in inshore waters close to their colonies (mean foraging range 5.2 ± Scotland’s seas 1.5 km, Thaxter et al, 2012) such that at-sea distribution in GB seas reflects that of coastal colonies. In in GB context 1999-2002, c.54% of the GB breeding population was in Scotland, with the largest single colony at North Sutor in the Moray Firth and other notable concentrations in the Outer Hebrides and SW coast (Mitchell et al, 2004). GB contribution Medium The most recent (1999-2002) estimate of the (coastal) GB breeding population of this regularly to biogeographic occurring migratory species is 6,820 pairs, equivalent to c.13% biogeographic population (carbo population World) estimated at 52,000 – 53,000 pairs (Mitchell et al, 2004)2.

Great cormorant have an extremely wide global range, breeding on every continent except South America and Antarctica (BirdLife International, 2018). The carbo subspecies to which coastal breeding birds in GB belong also breeds in Ireland, France, Greenland, Iceland, Norway, Russia, Canada and the USA (Mitchell et al, 2004).

1 Derived from the distribution models in WWT Consulting (2016) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Inland breeding Great cormorant in GB are almost entirely of the sinensis race; only coastal breeding birds, all carbo race are considered here. 152

European Least The European and global conservation status of Great cormorant is Least Concern ((BirdLife population Concern International, 2017 & 2018). conservation status Species’ status summary and Great cormorant (breeding) in GB are of Medium importance to the biogeographic population of this assessment of level of regularly occurring migratory species and the European population status is considered Least representation in Scottish Concern. Great cormorant (breeding) have a Highly Restricted distribution in GB waters, in coastal SPA network. areas in the vicinity of their colonies and just over half the breeding population are in Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of great cormorant (breeding) is Medium.

This assessment indicates there is an expectation of great cormorant (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of great cormorant (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK seas generating pressures or threats potentially having either high or medium threats and impacts on populations of great cormorant (Furness, 2016), but actual impacts on coastal nesting birds are poorly pressures documented. Great cormorants are attracted to finfish aquaculture sites where they may risk fatal entanglement in netting (Ross, 1988) and shooting (Carss, 1994); however, legal fatal control is now strictly regulated under licence and only permitted in instances of proven serious damage where alternative non-lethal methods of control have proved unsuccessful or impractical3. Cormorant species are highly susceptible to fatal entanglement in fishing gears (including trammel nets, set gill nets, bottom otter trawls and longlines) (ICES, 2013; Zydelis et al, 2013 ) and ghost fishing gear (Tasker et al, 2000). In the UK great cormorant are identified as among the most sensitive species to bycatch at depth near the seabed and in the top 50% of species with respect to sensitivity to bycatch in surface gears (Bradbury et al, 2017), but there is no systematic data from which to assess bycatch rates or impacts (ibid).

The potential impacts of climate change on breeding populations of great cormorant in the UK are uncertain (Pearce- Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

3 See https://www.nature.scot/sites/default/files/2017-07/B879290%20-%20Licence%20to%20prevent%20serious%20damage%20to%20fisheries%20- %20fish%20farms%20-%20Guidance%20-%20Version%202%20pdf%20-%20April%202015%232.pdf 153

3. Summary

The species assessment (Table 1) indicates there is an expectation of great cormorant (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

No marine proposed SPAs have been identified for great cormorant (breeding) in the Scottish pSPA network. Great cormorant (breeding) are represented in three existing colony SPAs, all in OSPAR Region II. All of these have 2km marine extensions for maintenance behaviours, but great cormorant were not the species driving these extensions.

The number and distribution of marine proposed sites for great cormorant (breeding) in the Scottish pSPA network as summarised above is below the minimum level of representation indicated by the species assessment (Table 1).

Great cormorant feed predominantly on a wide variety of coastal fish species and typically forage in shallow waters within 10km of their breeding colonies (BirdLife International, 2018). There is therefore potential for identification of marine sites within foraging range of major colonies. Analyses of the European Seabirds at Sea (ESAS) database undertaken to support site selection did not detect any great cormorant hotspots that were sufficiently large to hold birds in qualifying numbers (Kober et al, 2010), but this may in part reflect their strongly coastal distribution.

Representation in the Scottish marine pSPA network would be desirable given the relative value of protected areas in Scotland’s marine environment to the conservation of great cormorant (breeding) in Europe. Great cormorant populations are also potentially vulnerable to a number of threats and pressures associated with human activity in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of great cormorant (breeding) to such threats and pressures.

4. Conclusion

SPA provision or additional site-based and/or alternative conservation measures are recommended for great cormorant (breeding). Potentially suitable additional SPAs could probably be identified with relatively little additional work.

5. References

BirdLife International, 2018. Species factsheet, Phalacrocorax carbo. http://www.birdlife.org

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Carss, D.N. 1994. Killing of piscivorous birds at Scottish fin fish farms, 1984-1987. Biological Conservation, 68, 181-188

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Ross, A. 1988. Controlling nature’s predators on fish farms. Marine Conservation Society, Ross-on-Wye.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M.L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531– 547.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

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Great cormorant (non-breeding)

1. Introduction

Great cormorant (non-breeding) is a regularly occurring migratory species. No marine proposed SPAs have been identified for great cormorant (non-breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of great cormorant (non-breeding)

Species’ status Score Notes

GB marine Highly Great cormorant (non-breeding) have a highly restricted distribution in the GB marine environment distribution restricted (JNCC range score 9.5%1). The highest densities modelled from boat-based and aerial survey data across UK waters are generally close to shore along south-east and north-west England. Lower

densities were estimated on the Welsh coast, the east coast of Scotland, including Orkney, south-west Scotland and along the south coast of England (Bradbury et al, 2017). Significance of Low Carrs & Murray (2007) suggest 9,000-11,500 great cormorant winter in Scottish waters. This aligns Scotland’s seas with the Furness (2015) estimate of 13,061 wintering individuals (this estimate includes part of the east in GB context coast of north England). Carrs & Murray (2007) estimate represents c. 27-35% of the estimated number of birds overwintering in the UK (33,123 individuals; Furness, 2015). GB contribution Medium The best available estimate of the UK2 wintering population for this regularly occurring migratory to biogeographic species is 33,123 birds (Furness, 2015), which aligns with the Musgrove et al (2013) GB estimate of population 35,000 individuals. The estimate is approximately 28% of the biogeographic population estimated to be 120,000 birds (NW Europe; Wetlands International 2015) or approximately 10% of the Furness (2015) biogeographic population estimate (with connectivity to UK waters) of 324,000 birds. There is low to moderate uncertainty around the figures from Furness (2015), which could range from no more than 50% less or 80% more.

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Great cormorant are globally widespread, however the subspecies of great cormorant occurring in the UK (carbo) breeds in the UK, Scandinavia, Iceland and Greenland. European Least The global and European conservation status for great cormorant is Least Concern (BirdLife population Concern International, 2015 & 2017). conservation status Species’ status summary and Non-breeding great cormorant in GB are of medium importance to the biogeographic population of this assessment of level of regularly occurring migratory species. Their European population status is Least Concern. The species representation in Scottish has a highly restricted distribution in UK waters but within GB territorial waters Scotland is thought to SPA network. be of low importance. Accordingly, the over assessment of the relative importance of Scotland to great cormorant (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of great cormorant (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of great cormorant (non-breeding) populations to anthropogenic threats and pressures.

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3. Summary

The species assessment (Table 1) indicates there is an expectation of great cormorant (non- breeding) being represented once or twice in the Scottish SPA network.

No sites have been identified for great cormorant (non-breeding) in the Scottish pSPA network.

The number and distribution of marine proposed sites for great cormorant (non-breeding) in the Scottish pSPA network as summarised above is below the minimum level of representation indicated by the species assessment (Table 1).

Great cormorant populations are potentially vulnerable to a number of threats and pressures associated with human activity in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of great cormorant (non-breeding) to such threats and pressures.

4. Conclusion

SPA provision or additional site-based and/or alternative conservation measures are could be considered for great cormorant (non-breeding). Potentially suitable additional SPAs could probably be identified with relatively little additional work.

5. References

BirdLife International, 2015. Phalacrocorax carbo. The IUCN Red List of Threatened Species 2015: e.T22696792A60150397.

BirdLife International, 2017. Phalacrocorax carbo (amended version of 2016 assessment). The IUCN Red List of Threatened Species 2017: e.T22696792A111798805. http://dx.doi.org/10.2305/IUCN.UK.2017-1.RLTS.T22696792A111798805.en.

Carss, D.N. 1994. Killing of piscivorous birds at Scottish fin fish farms, 1984-1987. Biological Conservation, 68, 181-188

Carrs, D. & Murray, R. 2007. Great Cormorant. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 399 – 403. Scottish Ornithologists’ Club, Aberlady.

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ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Ross, A. 1988. Controlling nature’s predators on fish farms. Marine Conservation Society, Ross-on-Wye.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M.L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531– 547.

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8.

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Great crested grebe (non-breeding)

1. Introduction

Great crested grebe is a regularly occurring migratory species. No marine pSPAs have been identified for great crested grebe (non-breeding) in the Scottish marine pSPA network.

2. Species account

Table 1 Summary of status of great crested grebe (non-breeding).

Species’ status Score Notes

GB marine Widespread Great crested grebe (non-breeding) in GB winter inland on large lowland lakes and reservoirs and in distribution estuaries and along shallow coasts. They were recorded in 42.1% of coastal squares (and 40.6% of inland squares) surveyed for the 2007-11 Atlas (Balmer et al, 2014)1 and in an average of 30.8% of coastal core WeBS count sectors counted between 2011 and 20152. Significance of High (edge Both the breeding and wintering distribution in GB is restricted to lowland areas, with the greatest Scotland’s seas of range) concentrations in central and southern England (Balmer et al, 2014; Bradbury et al, 2017; Frost et al, in GB context 2017). The largest coastal concentration in GB is at Dungeness/Rye Bay with an average of over 2000 birds between 2011 and 2015 (Frost et al, 2017). Along non-estuarine coasts, the estimated population in Scotland is just 16 birds, equivalent to 0.3% of the GB total (Austin et al, 2017). The largest estuarine wintering populations in Britain are also in England/Wales (e.g. Dee Estuary); in Scotland estuarine populations are confined to the south (e.g. Solway, Clyde and Forth) and only 17.8% of coastal and 10.3% of inland Atlas squares surveyed generated winter records of great crested grebe1.

Hence, Scotland holds a very small proportion of the wintering (especially coastal) population of great-crested grebe (non-breeding) in GB, but is at the northern edge of the GB wintering range.

1 Data supplied on 19 February 2018 by the British Trust for Ornithology 2 Data supplied on 14 February 2018 by the British Trust for Ornithology, the Royal Society for the Protection of Birds and the Joint Nature Conservation Committee (the last on behalf of the statutory nature conservation bodies: Natural England, Natural Resources Wales and Scottish Natural Heritage and the Department of Agriculture, Environment and Rural Affairs, Northern Ireland) in association with the Wildfowl and Wetlands Trust 161

GB contribution Medium The GB wintering population of this regularly occurring migratory species is 19,000 birds (Musgrove et to biogeographic al, 2013) approximately 4.5 – 6.5% of the biogeographic population (cristatus, North-west & population Western Europe) estimated at 290,000 - 420,000 birds (Wetlands International, 2015 & 2018).

Great crested grebe has a very wide breeding range on large shallow freshwater bodies across most of Europe and central Asia and exhibits a range of dispersal, partial migratory and migratory behaviours (BirdLife International, 2018). Very large aggregations form in some coastal/estuarine locations during the post-breeding flightless moult, but other birds moult on their breeding grounds with later dispersal to wintering areas (Wernham et al, 2002). Winter WeBS counts indicate that larger wintering areas in the UK are split fairly evenly between inland waters and coast/estuaries. Across Europe the extent to which coastal waters are used is variable and related to severity of winter weather. In Northern Ireland tracking studies have confirmed linkage between the breeding population on inland Lough Neagh and coastal moulting/wintering aggregations on Belfast Lough, but little is known of the extent of movements between GB and Europe (Wernham et al, 2002). European Low The global and European conservation status for great crested grebe is Least Concern (Secure) population (BirdLife International, 2017 & 2018). conservation status Species’ status summary and The great crested grebe (non-breeding) population wintering in GB’s coastal waters is of Medium assessment of level of importance to the biogeographic wintering population of this regularly occurring migratory species in representation in Scottish Europe and the European population status is considered Least Concern. Great crested grebe (non- SPA network. breeding) have a widespread distribution across both freshwater and coastal sites and the majority of the GB population are in England and Wales; however southern Scotland is at the northern edge of the GB coastal range. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of great crested grebe (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of great crested grebe (non-breeding) being represented once or twice in the Scottish SPA network.

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Table 2 Vulnerability of great crested grebe (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is no specifically documented evidence of activities likely to occur in UK marine waters generating pressures threats and or threats likely to have either high or medium impacts on relevant populations of great crested grebe (non- pressures breeding) (Furness, 2016).

Great crested grebe (non-breeding) populations in the UK may be vulnerable decline in response to climate change (Pearce-Higgins et al, 2011). It is recognised that well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

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3. Summary

The species assessment (Table 1) indicates there is an expectation of great crested grebe (non-breeding) being represented once or twice in the Scottish SPA network.

No sites have been identified for great crested grebe (non-breeding) in the Scottish pSPA network.

The number and distribution of marine proposed sites for great crested grebe (non-breeding) in the Scottish pSPA network as summarised above is below the minimum level of representation indicated by the species assessment (Table 1).

Very few great crested grebe are associated with the non-estuarine coasts of Scotland (Austin et al, 2017). Great crested grebe (non-breeding) is represented within the non- breeding waterbird assemblages at the Firth of Forth and Upper Solway Flats and Marshes estuarine SPAs. The marine extension to the Upper Solway Flats and Marshes SPA forming the Solway Firth pSPA will incorporate great crested grebe as a named qualifier of the waterbird assemblage.

4. Conclusion

The existing estuarine SPAs lie within the core range for this species in Scotland on the east and west coasts respectively. Therefore the existing level of representation for great crested grebe within the marine SPA network is considered appropriate and reflects the relative value of protected areas in Scotland’s marine environment to the conservation of great crested grebe (non-breeding) in Europe.

No further SPA provision is considered necessary for great crested grebe (non-breeding).

5. References

BirdLife International, 2018. Species factsheet, Podiceps cristatus. http://www.birdlife.org

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SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds.) 2002. Migration Atlas: movements of birds of Britain and Ireland. Poyser, London

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

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Great northern diver (non-breeding)

1. Introduction

Great northern diver is an Annex 1 species. Great northern diver (non-breeding) is being considered for inclusion within 7 proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing proposed SPAs for great northern diver (non-breeding)

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2. Species account

Table 1 Summary of status of great northern diver (non-breeding)

Species’ status Score Notes

GB marine Restricted Great northern diver (non-breeding) have a restricted distribution in the GB marine environment (JNCC distribution range score 21.6%1). The highest densities modelled from boat-based and aerial survey data across

UK waters were around the western, northern and north-eastern (from Caithness to Angus) coasts of Scotland with lesser densities around southern and eastern coasts of England and up to 200km into the English North Sea (Bradbury et al, 2017). Significance of High Austin et al, 2017 estimated that over 90% of the GB population of great northern divers in non- Scotland’s seas estuarine coastal waters occur in Scotland and both this survey and the 2007-2011 Atlas (Balmer et in GB context al, 2014) identified the largest concentrations in the Northern Isles, Outer Hebrides and northwest Scotland south to Argyll, therefore Scotland has a particular responsibility for the species. GB contribution High The estimated GB wintering population of this Annex 1 species is 2,500 birds (Musgrove et al, 2013), to biogeographic which is approximately 50% of the biogeographic (European) population estimated at 5,000 birds population (Wetlands International, 2015, 2018) . However, more recent sources (e.g. Austin et al, 2017; Furness, 2015; Lawson et al, 2015) indicate that the GB wintering population exceeds 4000 birds. The current national and biogeographic wintering population estimates are awaiting systematic review and it is probable that the relative importance of GB and Scottish waters to the population wintering in Europe may be greater than previously thought.

Great northern diver breeds across northern North America, Greenland and in Iceland and winters on sea coasts or larger lakes over a much wider area including the Atlantic coast of Europe from Finland to Portugal and the western Mediterranean (BirdLife International, 2018). The birds wintering in GB waters are thought to derive mainly from the European breeding population in Iceland, Greenland and Baffin Island (total population estimated at 700-1,300 pairs, which equates to 1,400-2,600 mature individuals, BirdLife International, 2018) with a very small proportion coming from eastern Canada (Wernham et al, 2002; Furness, 2015).

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European High The European population conservation status is Vulnerable (BirdLife International, 2017). population The global conservation status is Least Concern; this reflects the large size and very extensive range of conservation the population in North America (BirdLife International, 2018) status Species’ status summary Great northern diver (non-breeding) have a Restricted distribution in GB inshore waters, mainly in and assessment of level of Scotland. GB is of High importance to the biogeographic wintering population of this Annex 1 species. representation in Scottish The European population status is considered Vulnerable and therefore measures to improve SPA network. conservation status are considered to be of high importance. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of great northern diver (non-breeding) in Europe is Very High.

This assessment indicates there is an expectation of great northern diver (non-breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of great northern diver populations to anthropogenic threats and pressures.

Vulnerability to There is no specifically documented evidence of activities in UK waters generating pressures or threats likely to threats and have either high or medium impacts on relevant populations of great northern divers during the non-breeding pressures season (Furness, 2016). However, great northern diver populations internationally are significantly impacted by accidental bycatch in fishing nets (Pokas, 2005 in Furness, 2016). Great northern divers are also susceptible to mortality arising from oil spills, and in some instances this has had long-term impacts on local wintering populations, which may reflect poor recruitment in associated breeding populations (Heubeck, 1997). There is currently a lack of published evidence for impacts of disturbance associated with vessel movements and related activities, but there is evidence that great northern divers take evasive avoidance action at distances of several kilometres from approaching vessels (Jarrett et al, 2018). Disturbance from shipping is identified as a medium level threat and pressure to non-breeding populations of both black-throated and red-throated divers (Furness, 2016). Therefore, there is potential for vessel movements and related activities to impact great northern divers. Whilst there is no specific evidence on the impacts of climate change to great northern divers (non-breeding), it is recognised that well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining

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diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

3. Contribution to Scottish SPA network

This section considers the occurrence of great northern diver (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Great northern diver (non-breeding) is being considered for inclusion at 7marine proposed SPAs. There are no existing SPAs for this species in Scotland.

Table 3 Summary of occurrence of great northern diver (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

East Mainland Supports c. 7.3 % of Great northern diver Provides an example in the Northern In Scotland there is Coast, Shetland the GB non-breeding (non-breeding) is Isles and represents the northern strong evidence of population. represented within 7 extent of the range of this species in winter site fidelity with proposed SPAs. Scotland. birds returning to the North Orkney Supports c. 12.4 % of Provides an example in the Northern same area from one the GB non-breeding There are no existing Isles and represents a core part of the winter to the next population. SPAs for this species range of this species in Scotland. (Heubeck, 1997; Scapa Flow Supports c. 20.2 % of in Scotland. Provides an example in the Northern Pennington et al, 2004; the GB non-breeding Isles and represents a core part of the Jardine & Fisher, population. Replication of this range of this species in Scotland. 2015). A study in North Moray Firth Supports c. 5.8 % of feature in the network Provides the only example on the east America also indicated the GB non-breeding is proposed in mainland coast and represents the that individual breeding population. OSPAR Regions II southern extent of the range of this adults are highly faithful and III. species in Scotland. to localised wintering Sound of Gigha Supports c. 20.2 % of Provides an example on the west areas (Paruk et al, the GB non-breeding mainland coast and represents the 2015). population. southern extent of the range of this species in Scotland.

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Proposed SPAs Representation Replication Geographic range Linkages

Coll and Tiree Supports c. 18.1 % of Provides only example in the Inner the GB non-breeding Hebrides, a core part of the range of population. this species in Scotland. West Coast of the Supports c. 52 % of the Provides only example in the Outer Outer Hebrides GB non-breeding Hebrides, a core part of the range of population. this species in Scotland.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of great northern diver (non-breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

The proposed SPA network includes seven pSPAs for great northern diver (non-breeding), of which four are in OSPAR Region II and three in Region III. Together they support an estimated 3,397 birds, which, as discussed above (Table 1) substantially exceeds the currently published GB population estimate (Musgrove et al, 2013). The proposed SPAs reflect the geographic range and variation of wintering great northern diver in Scotland from East Mainland Coast, Shetland in the far north east to the Sound of Gigha in southern Argyll and Moray Firth on the east coast. They also reflect the varied environments in which great northern divers occur (e.g. from the exposed West Coast of the Outer Hebrides to the more sheltered waters of sites such as Scapa Flow).

The number and distribution of proposed SPAs for great northern diver (non-breeding) in the Scottish network, as summarised above and in Table 3, is consistent with the species assessment (Table 1).

Great northern diver (non-breeding) is proposed for inclusion in all proposed SPAs where it has been identified as a qualifying feature and is represented more than once in each OSPAR region. Replication of sites ensures the full extent of the Scottish geographic range is encompassed and enhances network resilience (e.g. to threats such as oil spills, Heubeck, 1997). However, there is limited evidence of high or medium impacts to great northern diver (non-breeding) population in response to threats and pressures (Furness, 2016) and therefore, no additional replication beyond the species’ status assessment is considered necessary.

Within the Northern Isles in OSPAR Region II, there are three pSPAs for great northern diver (non-breeding); two in Orkney, at North Orkney and Scapa Flow, and one in Shetland. The East Mainland Coast, Shetland pSPA represents the northern extent of this species in GB. North Orkney pSPA and Scapa Flow pSPA represent the core part of the range of this species in Scotland, together supporting up to 32.6% of the GB population, second only to the contribution of the larger West Coast of the Outer Hebrides pSPA. Of the two Orkney sites, Scapa Flow pSPA holds the second largest number of great northern diver (non- breeding) in the Scottish pSPA network and North Orkney the fifth largest.

There are no existing SPAs for great northern diver (non-breeding) in Scotland. The available evidence does not suggest strong linkages between wintering areas for this species. Adult birds, wintering mainly in northern and western Scotland, are thought to be highly faithful to localised areas. Immature birds may be more mobile and substantial numbers remain in British waters through the summer.

5. Conclusion

The number and distribution of marine proposed SPAs for great northern diver (non- breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of great northern diver (non-breeding) in Europe.

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No further SPA provision is considered necessary for great northern diver (non-breeding) however, a review of the level of representation in the Northern Isles is required by the Advisory Panel.

6. References

Balmer, D., Gillings, S., Caffrey, B., Swann, B., Downie, I. & Fuller, R. 2014. Bird Atlas 2007-11: The Breeding and Wintering Birds of Britain and Ireland. BTO, BirdWatch Ireland, and SOC

BirdLife International, 2018. Species factsheet, Gavia immer. http://www.birdlife.org

Heubeck, M. 1997. The long-term impact of the Esso Bernicia oil spill on numbers of

Common Loons Gavia immer wintering in Shetland, Scotland. In: Effects of Oil on Wildlife. Fifth International Conference, November 3–6, Monterey, California: 110–122.

Jardine, D.C. & Fisher, I.A.2015. Site fidelity of Great Northern Diver with a deformed bill. Scottish Birds, 35, (2): 160-161.

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M. 2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

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Paruk, J.D., Chickering, M.D., Long IV, D., Uher-Koch, H., East, A. and Poleschook, D.2015. Winter site fidelity and winter movements in Common Loons (Gavia immer) across North America. The Condor, 117, (4), 485-493

Pennington, M., Osborn, K., Harvey, P., Riddington, R., Okill, D., Ellis, P. & Heubeck, M. 2004. The Birds of Shetland. Christopher Helm, London

Pokas, M.A. 2005. Common loons (Gavia immer) and fishing gear in New England: real problems, real solutions. Canadian Technical Report of Fisheries and Aquatic Sciences 2617: 107-108.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds.) 2002. Migration Atlas: movements of birds of Britain and Ireland. Poyser, London

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

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Great skua (breeding)

1. Introduction

Great skua is a regularly occurring migratory species. Great skua (breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for great skua (breeding)

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2. Species account

Table 1 Summary of status of great skua (breeding).

Species’ status Score Notes

GB marine Widespread Great skua (breeding) have a widespread distribution in the GB marine environment (JNCC range distribution score 96.6%1) . Modelling of boat-based and aerial survey data shows the greatest concentrations around Shetland and Orkney (Bradbury et al, 2017). The overall range in the summer months is considerably more extensive and includes a high density area off the east Yorkshire coast which is thought to be used by non-breeding or post-breeding birds (Bradbury et al, 2017; Stone et al, 1995). Significance of High The at sea distribution largely reflects that of breeding colonies of great skua in GB, with 100% of the Scotland’s seas breeding population in Scotland. Colonies are confined to coastal moorlands in the far north and in GB context west of Scotland, particularly in Shetland and Orkney, which in 1998-2002 held 71% and 23% respectively of the Scottish (GB) population (Mitchell et al, 2004). Smaller colonies are found further west, notably on Handa (Sutherland) and St Kilda. Breeding great skua typically forage within 100km of their nest sites (Thaxter et al, 2012; Wade et al, 2014). GB contribution High The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 9,634 pairs, equivalent to 60.0% of the biogeographic population (World) population estimated at 16,000 pairs (Mitchell et al, 2004). Breeding sites in northern Scotland are at the southern edge of the species’ breeding range.

Great skua breed in Iceland, Norway, Svalbard, the Faroe Islands and Scotland and normally winter off the Atlantic coast of France and the Iberian Peninsulas, although juveniles can reach as far as Cape Verde, the coast of Brazil, areas of the Caribbean and small numbers also winter on the Grand Banks of (BirdLife International, 2018) European Least The European and global conservation status of this regularly occurring migratory species is Least population concern Concern (Secure) (BirdLife International, 2017 & 2018). conservation status

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Species’ status summary and Breeding great skua in Scotland (GB) are of high importance to the biogeographic population of this assessment of level of regularly occurring migratory species and the European population status is considered Least Concern representation in Scottish (secure). Great skua (breeding) have a widespread distribution at sea, with the highest densities in SPA network. Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of great skua (breeding) in Europe is Medium.

This assessment indicates there is an expectation of great skua (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of great skua (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have high threats and medium impacts on relevant populations of great skua (breeding) (Furness, 2016). Recent declines in the breeding pressures population of great skuas in Orkney (Meek et al, 2011) and periods of very low breeding success at large colonies in Shetland2 have been linked to reduced sandeel abundance and decreases in fisheries discarding (Hamer et al, 1991; Caldow and Furness, 2000; Oswald et al, 2008). An offshore wind farm collision risk index identifies populations of skuas as one of the marine birds in Scottish waters most vulnerable to collision mortality impacts in offshore wind farms (Furness et al, 2013) although potential for interaction during the breeding season may currently be relatively restricted (Wade et al, 2014). Great skua are susceptible to capture in longline fisheries (ICES, 2013) but populations are not currently identified as vulnerable to bycatch in fishing gears in UK waters (Bradbury et al, 2017). However, there is no systematic data from which to assess bycatch rates or impacts (ibid).

Great skua are potentially vulnerable to direct and indirect (through changes to prey dynamics) impacts of climate change (Oswald et al, 2008) and have been identified as being at risk of extinction as a breeding species in Britain and Ireland (Russell et al, 2015). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Great skua (breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures. Replication within OSPAR regions is recommended.

2 http://jncc.defra.gov.uk/page-2879

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3. Contribution to Scottish SPA network

This section considers the occurrence of great skua (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Great skua (breeding) are being considered for inclusion at one marine proposed SPA and are represented in 9 existing colony SPAs, all of which have marine extensions, although not specifically for great skua.

Table 3 Summary of occurrence of great skua (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Seas off Foula Supports Great skua is represented Provides the only Birds foraging in the Seas off Foula are regularly within one proposed SPA example of this within foraging range of the breeding occurring and 9 existing SPAs, eight species in Scotland. colony at Foula SPA and within mean aggregation of of which have marine maximum foraging range (86.4km, Thaxter 1,594 foraging extensions. However, great et al, 2012) of an additional 5 colony SPAs great skua3. skua is not the species in Shetland, although recent tracking determining the extension. studies suggest that birds may tend to use areas in the vicinity of individual breeding No sites were identified in colonies Wade et al (2014). OSPAR Region III.

3 This is an average number of birds within a site, derived from analysis of densities using the ESAS dataset to identify areas of sea that on average held higher and more aggregated densities of birds than other areas (Kober et al, 2010). Essentially the average figure gives an indication of the relative importance of sites, it represents a snapshot of usage because the entire population of the relevant breeding colonies are not at sea at any one time and are not solely confined to those areas identified as pSPAs. The total number of individuals using the site over the breeding season will be well in excess of the estimate used for site selection purposes and will reflect the breeding populations at colonies within foraging range of the site and turnover within the site.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of great skua (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes one marine pSPA for great skua (breeding), holding an average of 1,594 birds3, within OSPAR region II, where over 90% of the GB population occur (Mitchell et al, 2004). The proposed site is within mean maximum foraging range of six breeding colony SPAs in Shetland.

The number and distribution of marine proposed sites for great skua (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation anticipated by the species assessment (Table 1).

Great skua (breeding) are at the southern edge of their breeding range in northern Scotland. Additional replication in the network would be desirable because great skua are vulnerable to changes in food availability associated with fisheries and have been assessed as vulnerable to extinction in Britain and Ireland as a consequence of climate change (Russell et al, 2015). They are also potentially vulnerable to collision with offshore wind turbines. Some of these threats and pressures require management at an ecosystem or broader scale but site-based protection of areas used regularly by large aggregations complements wider measures and is considered an appropriate conservation measure for great skua (breeding).

Population resilience would potentially be enhanced through identification of additional marine pSPAs, but no other hotspots of similar magnitude or density to that off Foula have been identified through analysis of the European Seabirds at Sea data (Kober et al, 2010 & 2012) and modelled at sea densities in OSPAR Region III are relatively low (Bradbury et al, 2017). The recent marked decline in the breeding population at the most important breeding site in Orkney (Hoy) may further decrease potential for identifying an additional marine site within the core breeding range of great skua in GB in OSPAR Region II.

Inclusion of the marine proposed SPA in the network provides added conservation value by safeguarding marine habitats supporting prey species used by great skua (breeding) from the breeding colony at Foula SPA and potentially an additional 5 colony SPAs in Shetland, although recent tracking studies suggest that birds may tend to use areas in the vicinity of individual breeding colonies Wade et al (2014).

5. Conclusion

The number and distribution of marine proposed SPAs for great skua (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of great skua (breeding) in Europe.

The case for inclusion of great skua (breeding) in the Seas off Foula pSPA is further supported because it is functionally linked to existing colony SPA(s).

Further SPA provision or additional site-based and/or alternative conservation measures are recommended for great skua (breeding). Substantial further work (including survey and/or additional analyses) would be required to identify potentially suitable sites.

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6. References

BirdLife International, 2018. Species factsheet: Catharacta skua. http://www.birdlife.org

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66

Hamer, K. C., Furness, R. W. and Caldow, R. W. G. (1991), The effects of changes in food availability on the breeding ecology of great skuas Catharacta skua in Shetland. Journal of Zoology, 223, 175–188. doi:10.1111/j.1469-7998.1991.tb04758.x

ICES 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM:77

Kober, K., Webb, A., Win, I., O’Brien, S., Wilson, L.J., & Reid, J.B. 2010. An analysis of the numbers and distribution of seabirds within the British Fishery Limit aimed at identifying areas that qualify as possible marine SPAs. JNCC Report No. 431.

Kober, K., Wilson, L.J., Black, J., O'Brien, S., Allen, S., Bingham, C., & Reid, J.B. 2012. The identification of possible marine SPAs for seabirds in the UK: The application of Stage 1.1- 1.4 of the SPA selection guidelines. JNCC Report No. 461.

Meek, E.R., Bolton, M., Fox, D., Remp, J., 2011. Breeding skuas in Orkney: a 2010 census indicates density-dependent population change driven by both food supply and predation. Seabird, 24, 1-10.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Oswald, S.A., Bearhop, S., Furness, R.W., Huntley, B. & Hamer, K.C. 2008. Heat stress in a high-latitude seabird: effects of temperature and food supply on bathing and nest attendance of great skuas Catharacta skua. Journal of Avian Biology, 39, 163-169.

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SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wade, H. M., Masden, E. A., Jackson, A. C., Thaxter, C. B., Burton, N. H. K., Bouten, W. & Furness, R. W. 2014. Great skua (Stercorarius skua) movements at sea in relation to marine renewable energy developments. Marine Environmental Research 10, 69–80.

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Great skua (non-breeding)

1. Introduction

Great skua is a regularly occurring migratory species. Great skua (non-breeding) is being considered for inclusion within one proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the proposed SPA for great skua (non-breeding)

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2. Species account

Table 1 Summary of status of great skua (non-breeding).

Species’ status Score Notes

GB marine Highly Highly restricted distribution in the GB marine environment. Low numbers of observations at sea are distribution restricted available for this species. The greatest densities modelled from boat-based and aerial survey data in English waters were in the seas off the south-west tip of England and in south-east England, at the opening of the English Channel (Bradbury et al, 2017). Corrected densities derived from sightings in Scottish waters indicate some clustering of observations to the west of the Outer Hebrides and in the Firth of Forth (Bradbury et al, 2017). Kober et al (2010) predict winter hotspots of great skuas around Shetland, east England and in the seas off the south-west tip of England.

These sources aggregate data from October to March (Bradbury et al, 2017) and September to April (Kober et al, 2010), which likely include observations of birds attending colonies prior to or after the breeding season, and migrating away from or returning to colonies. Data in Stone et al 1995 may more accurately describe the winter distribution of great skuas, indicating clusters of observations in the seas to the south-west of England and Ireland (Nov-Mar). This aligns with tracking data indicating great skuas winter in the Celtic Sea, Bay of Biscay and off West Africa (Magnusdottir et al, 2012). Significance of Low Furness (2007) estimates <10 great skuas winter in Scotland representing a maximum of c. 0.6% of Scotland’s seas the estimated number of birds overwintering in UK1 waters (1,541 individuals; Furness, 2015). in GB context GB contribution Medium The best available estimate of the UK wintering population of this regularly occurring migratory species to biogeographic is 1,541 birds (Nov-Feb; Furness, 2015), which is approximately 2% of the biogeographic population population (with connectivity to UK waters) estimated to be 73,000 birds (Furness, 2015). Estimates of populations migrating through UK waters range from 33,575-35,892 birds (Mar-Apr, Aug-Oct; Furness, 2015), which equates to 46-49% of the biogeographic population. There is moderate and high uncertainty associated with these figures, which could range from greater than 50% less to 80% more (Furness, 2015).

1 Furness (2015) provides UK reference populations rather than at a GB scale.

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Approximately 60% of the global population of great skuas breed in GB. GB breeding populations occur in north and north-west Scotland, with over 90% of the GB population breeding in Shetland and Orkney. The largest GB breeding colony is on Foula, Shetland. Other breeding populations are found in Iceland, Faroe Islands, Norway and Russia. Scotland is the southern limit for breeding great skua (Furness 2007). Few birds remain in the North Sea in winter, with the main wintering distribution ranging from the Celtic Sea to the coast of West Africa. The Bay of Biscay is of particular importance for wintering birds (Furness, 2007, Magnusdottir et al, 2012). European Least The global and European conservation status for great skua is Least Concern (BirdLife International, population Concern 2015 & 2017). conservation status Species’ status summary and The European population status of great skua (non-breeding) is considered Least Concern with GB of assessment of level of medium importance to the biogeographic population of this regularly occurring migratory species. representation in Scottish Great skua (non-breeding) have a highly restricted distribution in the GB marine environment. Data for SPA network. this species are lacking but evidence indicates the highest densities of wintering birds occur in the seas to the south-west of England and Ireland (Stone et al, 1995; Magnusdottir et al, 2012; Kober et al, 2010; Bradbury et al, 2017). Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of great skua (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of great skua (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of great skua (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of great skua (non-breeding) (Furness, 2016). These include competition with commercial pressures fisheries for prey resources (e.g. sandeels) (Caldow & Furness, 2000), changes to fisheries management aimed at reducing levels of fisheries discards (Votier et al, 2004; Bicknell et al, 2013), accidental bycatch on longlines (Bradbury et al, 2017) and collision with offshore wind turbines (Furness et al, 2013). Other pressures and threats include organochlorine pollution (Camphuysen et al, 2010). Competition with fisheries for resources and accidental bycatch are also likely to occur in wintering areas outside UK waters.

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Research suggests great skua populations will be affected by climate change (Oswald et al, 2008 & 2011) with one model predicting that the species could become close to or completely extinct in the British Isles under certain emissions scenarios (Russell et al, 2015). Until more evidence is available well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Great skua (non-breeding) populations are vulnerable to medium impacts from a number of different threats and pressures. Replication within OSPAR should be considered.

3. Contribution to Scottish SPA network

This section considers the occurrence of great skua (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Great skua (non-breeding) are being considered for inclusion at one marine proposed SPA and are represented in eight existing colony SPAs.

Table 3 Summary of occurrence of herring gull (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Seas off Foula Supports a non- Great skua (non-breeding) Provides the only Although non-breeding great skuas breeding seabird is represented within one example for this winter in the Celtic Sea, Bay of Biscay assemblage, proposed SPA. species in Scotland. and off West Africa, at sea data including great indicate birds may be attending There are eight existing skua equivalent to colonies at the start and end of the colony SPAs for breeding c. 21% of the UK non-breeding season (Stone et al great skua in Scotland. non-breeding 1995, Kober et al, 2010, Bradbury et population. No sites were identified in al, 2017). Great skuas attending the OSPAR Region III. Foula SPA colony could forage in the

Seas off Foula pSPA (Thaxter et al, 2012; Wade et al, 2014).

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4. Summary

The species assessment (Table 1) indicates there is an expectation of great skua (non- breeding) being represented once or twice in the Scottish SPA network.

The proposed Scottish SPA network includes one marine pSPA for great skua (non- breeding) supporting c. 21% of the GB non-breeding population. The pSPA occurs in OSPAR Region II. No sites were identified in OSPAR Region III.

The number of marine proposed sites for great skua (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the level of representation indicated by the species assessment (Table 1).

Great skua (non-breeding) populations have been identified as vulnerable to anthropogenic threats or pressures that may have medium impacts (Furness, 2016) including competition with commercial fisheries for prey resources (e.g. sandeels) (Caldow & Furness, 2000), changes to fisheries management aimed at reducing levels of fisheries discards (Votier et al, 2004; Bicknell et al, 2013), accidental bycatch on longlines (Bradbury et al, 2017) and collision with offshore wind turbines (Furness et al, 2013). Other pressures and threats include organochlorine pollution (Camphuysen et al, 2010) and climate change (Oswald et al, 2008 & 2011, Russell et al, 2015).

Some anthropogenic pressures (e.g. competition with commercial fisheries for prey resources such as sandeels or collision as a result of offshore wind farm developments) could be managed through provision of site-based protection encompassing supporting habitats, such as foraging locations (Furness, 2016).

There could be linkages between the proposed SPA and the existing terrestrial SPA for this species on Foula. At sea observations suggest birds may attend colonies at the start and end of the non-breeding season (Stone et al, 1995; Kober et al, 2010; Bradbury et al, 2017) and could therefore forage within the pSPA during this time (Thaxter et al, 2012; Wade et al, 2014).

5. Conclusion

The number and distribution of marine proposed SPAs for great skua (non-breeding) is fully justified both in terms of meeting the UK SPA Selection guidelines and the relative value of protected areas in Scotland’s marine environment to the conservation of great skua (non- breeding) in Europe.

No further SPA provision is considered necessary for great skua (non-breeding) however, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing great skua (non-breeding) populations at the wider seas/ecosystem level.

6. References

BirdLife International, 2015. Catharacta skua. The IUCN Red List of Threatened Species 2015: e.T22694160A60077340.

BirdLife International, 2017. Catharacta skua (amended version of 2016 assessment). The IUCN Red List of Threatened Species 2017: e.T22694160A110633436. http://dx.doi.org/10.2305/IUCN.UK.2017-1.RLTS.T22694160A110633436.en.

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Camphuysen, C.J., Schouten, S. & Gronert, A. 2010. Mystery spill of Polyisobutylene (C4H8) off the Dutch coast affecting seabirds in March 2010. Seabird, 23, 143-145.

Furness, R.W. 2007. Great Skua. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 735 – 738. Scottish Ornithologists’ Club, Aberlady.

Magnusdottir, E., Leat, E.H.K., Bourgeon, S., Strøm, H., Petersen, A., Phillips, R.A., Hanssen, S.A., Bustnes, J.O., Hersteinsson, P. & Furness, R.W. 2012. Wintering areas of Great Skuas Stercorarius skua breeding in Scotland, Iceland and Norway. Bird Study, 59, (1), 1-9.

Oswald, S.A., Huntley, B., Collingham, Y.C., Russell, D.J.F., Anderson, B.J., Arnold, J.M., Furness, R.W. & Hamer, K.C. 2011. Physiological effects of climate on distributions of endothermic species. Journal of Biogeography, 38, 430-438.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Thaxter, C.B., Ross-Smith, V.H., Clark, N.A., Conway, G.J., Rehfisch, M.M., Bouten, W., & Burton, N.H.K. 2011. Measuring the interaction between marine features of Special Protection Areas with offshore wind farm development zones through telemetry: first breeding season. Report to the Department of Energy and Climate Change. No. 590.

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Votier, S.C., Furness, R.W., Bearhop, S., Crane, J.E., Caldow, R.W.G., Catry, P., Ensor, K., Hamer, K.C., Hudson, A.V., Kalmbach, E., Klomp, N.I., Pfeiffer, S., Phillips, R.A., Prieto, I. & Thompson, D.R. 2004. Changes in fisheries discard rates and seabird communities. Nature, 427, 727-730.

Wade, H.M., Masden, E.A., Jackson, A.C., Thaxter, C.B., Burton, N.H.K., Bouten, W. & Furness, R.W. 2014. Great skua (Stercorarius skua) movements at sea in relation to marine renewable energy developments. Marine Environmental Research, 101, 69-80.

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Greater scaup (non-breeding)

1. Introduction

Greater scaup is a regularly occurring migratory species. Greater scaup (non-breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for greater scaup (non-breeding)

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2. Species account

Table 1 Summary of status of greater scaup (non-breeding).

Species’ status Score Notes

GB marine Restricted Greater scaup (non-breeding) have a restricted winter coastal distribution in GB. They were present distribution in 35.7% of coastal squares surveyed for the 2007-11 Atlas (Balmer et al, 2014)1 and in an average of 10.5% of coastal core WeBS count sectors counted between 2011 and 20152. The species also winters on freshwater sites (present in 26.0% of inland Atlas squares1). Significance of High Greater scaup are largely absent from mainland northern and western Scotland. Notable aggregations Scotland’s seas occur at a few locations around the British coast, notably Moray Firth, Loch Ryan, Solway Firth and in GB context also Loch Indaal on Islay (Lawson et al, 2015) and Scotland has a particular responsibility for the species. Changes in Scottish distribution since 1970s have been associated with improvements in sewage treatment in major estuaries, especially Firth of Forth and there has been a notable expansion in Northern Isles since 1980s (Balmer et al, 2014). GB contribution Medium The GB wintering population of this regularly occurring migratory species is 5,200 birds (Musgrove et to biogeographic al, 2013) and represents 1.7% of the biogeographic (Northern Europe/Western Europe) population population of 310,000 birds (Wetlands International, 2015 & 2018).

The global population is estimated to number c. 5,000,000 individuals with a breeding range across the northern limits of Europe (including Iceland), Asia and North America (BirdLife International, 2017a). Greater scaup wintering in Britain and Ireland are derived mainly from the Icelandic breeding population (Wright et al, 2012; Balmer et al, 2014 ) European Vulnerable The European conservation status for greater scaup is Vulnerable while IUCN global status is Least population Concern (BirdLife International, 2017a &b). This reflects the apparent decline in the western conservation European population since mid-1990s and the much larger size and extensive range of the global status population.

1 Data supplied on 19 February 2018 by the British Trust for Ornithology. 2 Data supplied on 14 February 2018 by the British Trust for Ornithology, the Royal Society for the Protection of Birds and the Joint Nature Conservation Committee (the last on behalf of the statutory nature conservation bodies: Natural England, Natural Resources Wales and Scottish Natural Heritage and the Department of Agriculture, Environment and Rural Affairs, Northern Ireland) in association with the Wildfowl and Wetlands Trust

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Species’ status summary and Greater scaup (non-breeding) population have a restricted distribution in GB nearshore waters with assessment of level of notable aggregations confined to Scotland. The GB wintering population is of medium importance to representation in Scottish the biogeographic population of this regularly occurring migratory species. The European population SPA network. status is considered Vulnerable, and therefore measures to improve conservation status are considered to be of high importance. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of greater scaup (non-breeding) is Very High.

This assessment indicates there is an expectation of the species being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience

Table 2 Vulnerability of greater scaup (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have either threats and medium impacts on relevant populations of greater scaup (non-breeding) (Furness, 2016). In particular, greater pressures scaup populations have been identified as vulnerable to: changes in availability of favoured bivalve prey associated with harvesting or modification of benthic habits through dredging; chronic oil pollution and spills; and, disturbance of their near-shore daytime roost sites associated with recreational activities (Mendel et al, 2008).

In their main European wintering grounds in the Baltic and at Lake Ijsselmeer in the Netherlands, greater scaup populations are also vulnerable to impact through fatal entanglement in set net fisheries (Mendel et al, 2008; Žydelis et al, 2013). Empirical data on bycatch in British waters are lacking, but greater scaup are identified as among the most sensitive species for bycatch at depth near the seabed, with some areas of relatively high potential vulnerability in the winter months encompassing areas with high greater scaup densities (Bradbury et al, 2017).

Greater scaup show sensitivity to visual disturbance associated with vessel movements (Mendel et al 2008) but the potential significance of such disturbance on populations of nocturnal feeders such as greater scaup, is unknown (Platteeuw & Beekman, 1994).

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Greater scaup populations at their breeding grounds are identified as being vulnerable to changes in population dynamics and phenology linked to climate change (Ross et al, 2015). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Greater scaup populations are vulnerable to medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of greater scaup (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Greater scaup (non-breeding) is being considered for inclusion at one marine proposed SPA and is a feature of the non-breeding waterbird assemblage at four existing estuarine SPAs, two of which are contiguous with the marine proposed SPA.

Table 3 Summary of occurrence of greater scaup (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Moray Firth Supports c. Greater scaup (non-breeding) is Provides the only Greater scaup (non-breeding) 17.9% of the GB represented within one proposed example of this species is a feature of the non- non-breeding SPA and 4 existing estuarine in Scotland. breeding waterbird population. SPAs. assemblage of the Inner Moray Firth SPA and Cromarty Firth

SPA which are contiguous with No sites were identified in OSPAR this marine proposed SPA. Region III.

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4. Summary

The species assessment (Table 1) there is an expectation of the species being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

The Scottish SPA network includes one marine proposed SPA for greater scaup (non- breeding) and four existing estuarine SPAs. The marine proposed SPA in OSPAR Region II supports up to 17.9% of the GB non-breeding population. The location of the proposed SPA does not reflect the full geographic range of greater scaup (non-breeding) in Scotland as notable concentrations of greater scaup also occur in marine areas on the west coast (Lawson et al, 2015).

The number and distribution of proposed sites for greater scaup (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation anticipated by the species assessment (Table 1). There are no proposed SPAs in OSPAR Region III where some of the highest densities are located, although greater scaup are represented within one existing estuarine SPA (Upper Solway Flats and Marshes) in this region. Furthermore, there is no replication of sites within OSPAR regions.

Replication in the network is desirable because there is evidence that greater scaup (non- breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Additional site-based protection would enhance resilience of the species in Scotland and GB.

Inclusion of the Moray Firth pSPA in the network provides added conservation value by encompassing the full range of habitats used by greater scaup (non-breeding) also present in the Inner Moray Firth SPA and Cromarty Firth SPA. Together these sites encompass the full range of habitats used by greater scaup (non-breeding).

5. Conclusion

The number and distribution of marine proposed SPAs for greater scaup (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of greater scaup (non-breeding) in Europe.

Further SPA provision or additional site-based and/or alternative conservation measures are recommended for greater scaup (non-breeding). Potentially suitable additional SPAs could probably be identified with relatively little additional work.

6. References

BirdLife International, (2017a). Species factsheet: Aythya marila. http://www.birdlife.org

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Platteeuw, M. & Beekman, J.H. (1994) Disturbance of waterbirds by ships on lakes Ketelmeer and IJsselmeer. Limosa, 67, (1): 27-33

Ross, B.E., Hooten, M.B., Devink, J.M. & Koons, D.N. 2015. Combined effect of climate, predation, and density dependence on greater and lesser scaup population dynamics. Ecological Applications, 25, 1606-1617.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76–88.

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Herring gull (breeding)

1. Introduction

Herring gull is a regularly occurring migratory species. Herring gull (breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for herring gull (breeding)

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2. Species account

Table 1 Summary of status of herring gull (breeding).

Species’ status Score Notes

GB marine Widespread Herring gull (breeding) have a widespread distribution in the GB marine environment (JNCC range distribution score 95.0%1). Modelling of boat-based and aerial survey data across UK waters shows moderate

densities in nearshore waters around much of GB (Bradbury et al, 2017), reflecting the fairly even distribution of colonies (Mitchell et al, 2004). Significance of Moderate Coastal breeding herring gulls are relatively evenly distributed around GB, with the notable exception Scotland’s seas of eastern England from Flamborough Head to The Wash (Mitchell et al, 2004). In 1998-2002, 53.5% in GB context of coastal breeding herring gulls in GB were found in Scotland and two of seven colonies in GB with more than 2000 pairs were in Scotland (at Aberdeen City and Isle of May in the Firth of Forth (ibid). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 133,868 pairs, equivalent to 17.9 – 20.3% of the biogeographic population population (argentatus & argenteus NW Europe and Iceland/W Europe) estimated at 705,000 – 799,000 pairs (Mitchell et al, 2004).

The biogeographic population of this taxonomically complex species group breeding in NW Europe includes the races Larus argentatus argentatus and L.a. argenteus and their intergrades (Mitchell et al, 2004) Breeding populations are found in over twenty European countries most notably centred in Britain and Ireland, Scandanavia, The Netherlands, Germany and France (ibid). European Declining The European conservation status of herring gull is Declining and the global status is Least Concern population (BirdLife International, 2017 & 2018). conservation status This reflects recent declines at a rate approaching 30% in three generations but also the very large size and range of the population.

Species’ status summary and The European population status of breeding herring gull is considered Declining and GB is of Medium assessment of level of importance to the biogeographic population of this regularly occurring migratory species. Herring gull

representation in Scottish (breeding) have a widespread and relatively even distribution at sea around GB with just over half the SPA network. breeding population found in Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of herring gull (breeding) in Europe is Low.

This assessment indicates there is an expectation of herring gull (breeding being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of herring gull (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have either threats and high or medium impacts on relevant populations of herring gull (Furness, 2016). In particular, herring gull pressures populations are vulnerable to reductions in availability of fisheries waste and/or discards (Mitchell et al, 2004; Dunn, 1997; Furness et al, 1992). They are also among the seabird species assessed as most at risk of impacts through collision with offshore wind turbines (Furness et al, 2013; Johnston et al, 2014) although in the breeding season their distribution may reduce risk of interaction (Camphuysen, 2013 in Furness, 2015).

Herring gull populations may also be impacted by reduced availability of food from landfill sites (associated with changes in refuse management), outbreaks of botulism, and culling (Camphuysen, 2013 in Furness, 2016; Mitchell et al, 2004) and determining the main drivers of change at colony, regional or national levels is complex (Coulson, 2015). There are also potential differences in ecology between the growing population of urban roof-nesting gulls and those birds using more natural nest sites and differences between individuals in foraging strategies and extent of reliance on marine versus terrestrial food sources(Coulson, 2015; Rock et al, 2016).

There are recorded incidences of gull entanglement in fishing gear, most likely during hauling (Žydelis et al, 2013) and gull species are also susceptible to bycatch in longline fisheries (ICES, 2013), but the sensitivity of herring gull to potential bycatch in fisheries operating in UK waters is judged to be low (Bradbury et al, 2017).

The potential impacts of climate change on herring gull are uncertain but one analysis suggests a UK population rise and westerly redistribution (Pearce-Higgins et al, 2011). Another model suggests that European range size may decrease by at least 25% (Russell et al, 2015) Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

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Herring gull (breeding) populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions should be considered.

3. Contribution to Scottish SPA network

This section considers the occurrence of herring gull (breeding) within the proposed SPAs and existing SPAs in Scotland. Herring gull (breeding) are being considered for inclusion at one marine proposed SPA and are represented in eight existing colony SPAs, all of which have marine extensions classified to protect areas used by various other cliff-nesting seabird species for maintenance behaviours, such as preening, loafing and roosting, close to the colony.

Table 3 Summary of occurrence of herring gull (breeding) within proposed SPAs in the Scottish MPA network

Proposed Representation Replication Geographic Linkages SPAs range

Outer Firth of Supports a Herring gull (breeding) is Provides only Birds foraging in the Outer Firth of Forth Forth & St breeding represented within one proposed example of this and St Andrews Bay Complex are within Andrews Bay seabird SPA.and 8 existing SPAs, all of species in mean foraging range (10.5km, Thaxter et Complex assemblage, which have marine extensions. Scotland. al, 2012) of the breeding colonies at Forth including 3,044 However, herring gull is not the Islands SPA and St Abb’s Head to Fast herring gull2. species determining the extension. Castle SPA and additionally within mean maximum foraging range (61.1 km, ibid) of No sites were identified in OSPAR Fowlsheugh SPA. Region III.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of herring gull (breeding) being represented once or twice in the Scottish SPA network.

The proposed Scottish SPA network includes one marine pSPA for herring gull (breeding) holding an average of 3,044 birds2. The site is in OSPAR region II, which holds the largest herring gull colonies in Scotland (Mitchell et al, 2004), including those in the Firth of Forth SPA, which are functionally linked to the proposed marine site.

The number and distribution of marine proposed sites for herring gull (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the level of representation anticipated by the species assessment (Table 1).

Replication in OSPAR regions overlapping the Scottish distribution of herring gull (breeding) could be considered because herring gull (breeding) populations are vulnerable to changes in food availability (particularly fisheries waste and discards) and to collision with wind turbines. In conjunction with wider seas measures, site-based protection of marine areas used regularly by aggregations of herring gull (breeding) is considered an appropriate conservation measure to enhance resilience to such threats and pressures.

The Outer Firth of Forth & St Andrews Bay Complex pSPA is within foraging range of at least two of eight breeding colony SPAs and provides added conservation value by safeguarding marine habitats used by herring gull (breeding) from existing colony SPAs.

5. Conclusion

The number and distribution of marine proposed SPAs for herring gull (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of herring gull (breeding) in Europe.

No further SPA provision is considered necessary for herring gull (breeding) however, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing herring gull (breeding) populations at the wider seas/ecosystem level.

6. References

BirdLife International, 2018. Species factsheet, Larus argentatus. http://www.birdlife.org

Camphuysen, C.J. 2013. A historical ecology of two closely related gull species (Laridae): multiple adaptations to a man-made environment. PhD thesis, University of Groningen.

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Coulson, J.C. 2015. Re-evaluation of the role of landfills and culling in the historic changes in the herring gull (Larus argentatus) population in Great Britain. Waterbirds, 38, 339-354.

Dunn, E. 1997. Sustainable fisheries and seabirds. RSPB Conservation Review, 11, 44-50

Furness, R.W., Ensor, K. & Hudson, A.V. (1992). The use of fishery waste by gull populations around the British isles. Ardea, 80, 105-113

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Rock, P., Camphuysen, C.J., Shamoun-Baranes, J., Ross-Smith, V.H., &. Vaughan, I.P.2016. Results from the first GPS tracking of roof-nesting Herring Gulls Larus argentatus in the UK. Ringing & Migration, 31, 1, 47-62, DOI: 10.1080/03078698.2016.1197698

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

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Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

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Herring gull (non-breeding)

1. Introduction

Herring gull is a regularly occurring migratory species. Non-breeding herring gull is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for herring gull (non-breeding)

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2. Species account

Table 1 Summary of status of herring gull (non-breeding).

Species’ status Score Notes

Firth, around the Mull of Kintyre and south-west England. Moderate densities were modelled along the east coast of Scotland and England, including Orkney, and in south-west Scotland (Bradbury et al, 2017). Kober et al (2010) indicate the area between the Mull of Kintyre, Islay and Northern Ireland has the greatest density of herring gulls (non-breeding) in UK waters. In addition, the Firth of Forth, Moray Firth, the north-east coast of England, and the sea between the Isle of Man and Northern Ireland are hotspots for herring gull (non-breeding). This species forages largely in terrestrial and intertidal (above mean low water springs) habitats, using marine areas to forage in association with fishing vessels and as night-time roosts (Monaghan, 2007; Camphuysen et al, 1995). Significance of Low Burton et al (2013) estimate 273,058 (252,574 – 293,613) herring gulls winter in Scotland representing Scotland’s seas c. 37% of the estimated number of birds overwintering in GB (729,801 individuals; Burton et al, 20132). in GB context GB contribution High The best available estimate of the GB wintering population of this regularly occurring migratory to biogeographic species is 729,801(696,424 – 762,731; Burton et al, 2013) birds, which is approximately 66% of the population biogeographic population (with connectivity to UK waters) estimated to be 1,098,000 birds (Furness, 2015). Furness (2015) estimates a smaller UK3 wintering population of 639,810 birds, which equates to approximately 58% of the biogeographic population. There is moderate uncertainty associated with the Furness (2015) figures, which are likely to be no more than 50% less or 80% greater. A measure of uncertainty is indicated in the range associated with the Burton et al, 2013 estimates.

Herring gulls are distributed across northern and western areas of Europe. The subspecies L. a. argenteus breeds from Iceland, Faroe Islands, GB, Ireland, and western France to western Germany.

1 Derived from the distribution models in WWT Consulting (2016) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Data are calculated from counts of birds wintering in terrestrial and near-shore coastal waters; birds roosting offshore or not visible from land are not been included, which therefore may underestimate populations. 3 Furness (2015) provides UK reference populations rather than at a GB scale.

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This subspecies winters in the same areas but also south to Spain (Monaghan, 2007). Herring gulls in Britain and Ireland do not migrate and show only limited dispersal during winter, with adults tending to remain near to their breeding sites throughout the year (Furness, 2015). Immature birds move further than adults (Furness, 2015); the median dispersal distance being approximately 15km (Wernham et al, 2002). Birds tend to disperse southwards and remain near the coast. Low densities occur in pelagic waters, although herring gulls show a strong association with the distribution of fishing vessels in winter, congregating in areas where fisheries discards are available (Camphuysen et al 1995, Furness, 2015). European Near The global conservation status for herring gull is Least Concern whilst the European conservation population Threatened status is Near Threatened (BirdLife International, 2015 & 2016 & 2017). conservation status The species has an extremely large range and population in a global context. However, herring gulls have undergone moderately rapid declines in Europe, in both breeding and wintering populations (Burton et al, 2013), which accounts for the species European classification as Near Threatened. Species’ status summary and The European population status of herring gull (non-breeding) is considered Near Threatened with GB assessment of level of of High importance to the very large biogeographic population of this regularly occurring migratory representation in Scottish species. Herring gull (non-breeding) have a widespread distribution in the GB marine environment, SPA network. with the highest densities in the inner Moray Firth, and around the Mull of Kintyre and south-west England (Kober et al, 2010; Bradbury et al, 2017). This species forages largely in terrestrial and intertidal (above mean low water springs) habitats, using marine areas to forage in association with fishing vessels and as night-time roosts (Monaghan, 2007, Camphuysen et al 1995). Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of herring gull (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of herring gull (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of herring gull (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have high or medium impacts on threats and relevant populations of herring gull (non-breeding) (Furness, 2016). These include reduced availability of landfill pressures waste (Camphuysen, 2013), changes to fisheries management aimed at reducing levels of fisheries discards (Dunn 1997, Bicknell et al, 2013), contraction of botulism at landfill sites (Coulson, 2015) and collision with offshore wind

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turbines (Furness et al, 2013). Other pressures and threats include accidental bycatch in fishing nets (Žydelis et al, 2013; Bradbury et al, 2017), potential infection with H5N1 (Melville and Shortridge, 2006) oil pollution (Mendel et al, 2008) and organochlorine pollution (Camphuysen et al, 2010).

The potential impacts of climate change on herring gull in the UK are unclear. One model suggests herring gull populations could be negatively affected by climate change (Russell et al, 2015) whilst another suggests breeding populations may increase as a result of climate change (Pearce-Higgins et al, 2011). High uncertainty is associated with the Pearce-Higgins et al (2011) prediction and until more evidence is available well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Herring gull (non-breeding) populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions should be considered.

3. Contribution to Scottish SPA network

This section considers the occurrence of herring gull (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Herring gull (non-breeding) are being considered for inclusion at two marine proposed SPAs and are represented in eight existing colony SPAs.

Table 3 Summary of occurrence of herring gull (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports a non- Common gull (non-breeding) is Provides only example of this No known linkages. Forth & St breeding seabird represented within 2 proposed species on the east coast of Although adults tend to Andrews Bay assemblage, SPAs. Scotland. remain near to their Complex including common breeding sites throughout gull with equivalent

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Proposed SPAs Representation Replication Geographic range Linkages

to c. 1.7% of the There are eight existing the year (Furness, 2015) GB non-breeding breeding colony SPAs for this and some are within population. species in Scotland. foraging range of the pSPA (e.g. Forth Islands SPA) There is no replication of this (Thaxter et al, 2012). feature in the OSPAR regions. Solway Firth Supports a non- Provides only example of this No known linkages. breeding waterbird species on the west coast of Although adults tend to assemblage, Scotland. remain near to their including common breeding sites throughout gull with equivalent the year (Furness, 2015) to c. 0.4% of the and some are within GB non-breeding foraging range of the pSPA population. (e.g. Ailsa Craig SPA) (Thaxter et al, 2012).

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4. Summary

The species assessment (Table 1) indicates there is an expectation of herring gull (non- breeding) being represented once or twice in the Scottish SPA network.

The proposed Scottish SPA network includes two marine pSPAs for herring gull (non- breeding) supporting c. 2.1% of the GB non-breeding population. The pSPAs occur in OSPAR Regions II and III. This species forages largely in terrestrial and intertidal (above mean low water springs) habitats, using marine areas to forage in association with fishing vessels and as night-time roosts (Monaghan, 2007; Camphuysen et al, 1995).

The number of marine proposed sites for herring gull (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with species assessment (Table 1) but exceeds the minimum level of representation.

Replication in the network is considered appropriate because herring gull (non-breeding) populations have been identified as vulnerable to anthropogenic threats or pressures that may have medium or high impacts (Furness, 2016), including reduced availability of landfill waste (Camphuysen, 2013), changes to fisheries management aimed at reducing levels of fisheries discards (Dunn 1997, Bicknell et al, 2013), contraction of botulism at landfill sites (Coulson, 2015) and collision with offshore wind turbines (Furness et al, 2013). Other pressures and threats include accidental bycatch in fishing nets (Žydelis et al, 2013; Bradbury et al, 2017), potential infection with H5N1 (Melville and Shortridge, 2006) oil pollution (Mendel et al, 2008) and organochlorine pollution (Camphuysen et al, 2010).

Some anthropogenic pressures (e.g. collision as a result of offshore wind farm developments) could be managed through provision of site-based protection encompassing supporting habitats, such as foraging and roosting locations (Furness, 2016). The replication within the Scottish SPA network will enhance resilience and improves geographic representation.

The marine extension to the Upper Solway Flats and Marshes SPA forming the Solway Firth pSPA will incorporate herring gull as a named qualifier of the non-breeding waterbird assemblage and provides added conservation value by encompassing the full range of intertidal and subtidal habitats used by roosting non-breeding herring gull at this location.

There are no known linkages between the one existing terrestrial SPA for this species in Scotland and the pSPAs, although adults tend to remain near to their breeding sites throughout the year (Furness, 2015) and some are within foraging range of proposed SPAs (Thaxter et al, 2012).

5. Conclusion

The number and distribution of marine proposed SPAs for herring gull (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of herring gull (non-breeding) in Europe.

No further SPA provision is considered necessary for herring gull (non-breeding) however, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing herring gull (non-breeding) populations at the wider seas/ecosystem level.

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6. References

Bicknell, A.W.J., Oro, D., Camphuysen, K. & Votier, S.C. 2013. Potential consequences of discard reform for seabird communities. Journal of Applied Ecology, 50, 649–658.

BirdLife International, 2015. Larus argentatus. The IUCN Red List of Threatened Species 2015: e.T62030608A66711400.

BirdLife International, 2016. Larus argentatus. The IUCN Red List of Threatened Species 2016: e.T62030608A89504806. http://dx.doi.org/10.2305/IUCN.UK.2016- 3.RLTS.T62030608A89504806.en.

Camphuysen, C.J., Calvo, B., Durinck, J., Ensor, K., Follestad, A., Furness, R.W., Garthe, S., Leaper, G., Skov, H., Tasker, M.L. & Winter, C.J.N. 1995. Consumption of discards by seabirds in the North Sea. Final Report to the European Commission. NIOZ Report 1995-5. Netherlands Institute for Sea Research, Texel.

Camphuysen, C.J., Schouten, S. & Gronert, A. 2010. Mystery spill of Polyisobutylene (C4H8)n off the Dutch coast affecting seabirds in March 2010. Seabird, 23, 143-145.

Camphuysen, C.J. 2013. A historical ecology of two closely related gull species (Laridae): multiple adaptations to a man-made environment. PhD thesis, University of Groningen.

Coulson, J.C. 2015. Re-evaluation of the role of landfills and culling in the historic changes in the herring gull (Larus argentatus) population in Great Britain. Waterbirds, 38, 339-354.

Dunn, E. 1997. Sustainable fisheries and seabirds. RSPB Conservation Review, 11, 44- 50.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

Melville, D.S. and Shortridge, K.F. 2006. Migratory waterbirds and avian influenza in the East Asian-Australasian Flyway with particular reference to the 2003-2004 H5N1 outbreak. In: G. Boere, C. Galbraith & D. Stroud (eds.), Waterbirds around the world, pp. 432-438. The Stationery Office, Edinburgh, U.K.

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Monaghan, P. 2007. Herring Gull. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 776 – 781. Scottish Ornithologists’ Club, Aberlady.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. 2002. The Migration Atlas: movements of the birds of Britain and Ireland. Poyser, London

Žydelis, R., Small, C., French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-88.

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Leach's storm-petrel (breeding)

1. Introduction

Leach's storm-petrel (breeding) is an Annex 1 species. No marine proposed SPAs have been identified for Leach's storm-petrel (breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of Leach's storm-petrel (breeding)

Species’ status Score Notes

GB marine Highly Leach’s storm petrel (breeding) have a highly restricted distribution in the GB marine environment distribution restricted (present in 16% of 100km squares in GB waters; JNCC derived from Kober et al, 2010). Modelling of boat-based and aerial survey data across UK waters shows that in the breeding season

notable densities of Leach’s storm petrel are confined to the shelf break and deeper waters to the north-west of Scotland (Bradbury et al, 2017; Stone et al, 1995). Significance of High The distribution of Leach’s storm-petrel in GB seas reflects the very restricted northerly and westerly Scotland’s seas breeding distribution with 100% of breeding birds at just a handful of remote breeding sites in in GB context Scotland, the vast majority in a number of colonies at St Kilda (Mitchell et al, 2004). GB contribution Low The most recent (1998-2002) estimate of the GB breeding population of this Annex 1 species is to biogeographic 37,000 to 65,000 pairs, equivalent to 0.7 – 1.3% of the very large biogeographic population population (leucorhoa North Atlantic) estimated at 4,900,000 – 5,000,000 pairs, which represents roughly half of the global population (Mitchell et al, 2004).

Leach’s storm petrel has a very extensive global range, mainly in the northern hemisphere, from the South Kuril Islands (Japan) to Baja California (Mexico) and including the Aleutian Islands and Canada in the Pacific, and north-east North America, Iceland, Faeroe Islands, Scotland and Norway in the Atlantic. Small numbers also breed off South Africa (BirdLife International, 2018; Mitchell et al, 2004) European Least The European conservation status of Leach’s storm-petrel is Least Concern (Secure) and the global population Concern status is Vulnerable (BirdLife International, 2017 & 2018). conservation status

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The global listing is based on compilation of available data collected from 1977 to 2016 representing 75-80% of the global population (including Europe, eastern North America, and Japan), that points to a decline of ≥30% over three generations (BirdLife International, 2018). Species’ status summary and Leach's storm-petrel (breeding) in GB are of Low importance to the very large biogeographic assessment of level of population of this Annex 1 species and the European population status is considered Least Concern representation in Scottish (Secure). Leach's storm-petrel (breeding) have a Highly Restricted distribution in GB waters almost SPA network. entirely confined to offshore waters west of Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of Leach’s storm-petrel (breeding) is Medium.

This assessment indicates there is an expectation of Leach’s storm-petrel (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of Leach's storm-petrel (breeding) populations to anthropogenic threats and pressures.

Vulnerability to Leach’s storm-petrels are highly vulnerable to depredation by introduced mammalian predators at their breeding threats and colonies (Tasker, 2007) and in addition depredation by great skuas has been identified as a possible driver of pressures observed population declines at St Kilda (Newson et al, 2008), but there is no specifically documented evidence of activities in UK waters generating pressures or threats likely to have either high or medium impacts on relevant populations (Furness, 2016).

There are recorded incidences of storm-petrel entanglement in fishing gear, most likely during hauling (Žydelis et al, 2013) but the sensitivity of Leach’s storm-petrel to potential bycatch in fisheries operating in UK waters is judged to be low (Bradbury et al, 2017). Leach’s storm-petrels are known to ingest plastic particles (Furness, 1985) but the significance of any impacts is unknown.

There are limited data to inform potential impacts of climate change on Leach’s storm petrel (Pearce-Higgins et al, 2011), but one model suggests that they may become close to or completely extinct in the British Isles, depending on the emissions scenario (Russell et al, 2015). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

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3. Summary

The species assessment (Table 1) indicates there is an expectation of Leach’s storm-petrel (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

No marine proposed SPAs have been identified for Leach's storm-petrel (breeding) in the Scottish pSPA network. Leach's storm-petrel (breeding) are represented in six existing colony SPAs. These are split evenly between OSPAR Regions II and III but the SPA colonies in Shetland and Orkney are very small compared with those in the species’ core range in the Outer Hebrides. However, the distribution of Leach’s petrel at sea is concentrated in deep waters at the outer edges of OSPAR Region III and in Region V.

Hence, the number and distribution of marine proposed sites for Leach's storm-petrel (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation indicated by the species assessment (Table 1).

Representation in the Scottish marine SPA network would be desirable because Leach’s petrel is an Annex 1 species. However, Leach’s storm-petrel is a highly pelagic species, feeding on macro-zooplankton (e.g. myctophids, amphipods, euphausiids) taken from the ocean surface over deep oceanic waters. Analyses of the European Seabirds at Sea (ESAS) database undertaken to support marine SPA selection indicates that there may be one or more regularly occurring hotspots for Leach's storm-petrel (breeding) in offshore waters to the northwest of Scotland in OSPAR Region V (Kober et al, 2010). However, limited survey coverage in this area reduces level of confidence in robust site identification from this analysis alone (ibid).

4. Conclusion

SPA provision or additional site-based and/or alternative conservation measures are recommended for Leach's storm-petrel (breeding). There is potential for identification of marine sites encompassing consistently important foraging areas for Leach’s storm-petrel (breeding) in OSPAR Region V; additional targeted survey effort would assist this.

5. References

BirdLife International, 2018. Species factsheet, Oceanodroma leucorhoa. http://www.birdlife.org

Furness, R.W. 1985. Plastic particle pollution: accumulation by Procellariiform seabirds at Scottish colonies. Marine Pollution Bulletin, 16, 103-106.

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Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Newson, S. E., Mitchell, P., Parsons, M., O’Brien, S. H., Austin, G. E., Benn S., Black J., Blackburn, J., Brodie, B., Humphreys, E., Leech, D., Prior, M. & Webster, M. 2008. Population decline of Leach’s Storm-petrel Oceanodroma leucorhoa within the largest colony in Britain and Ireland. Seabird, 21, 77-84.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M.L. 2007. Leach's Storm-petrel. In: Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 2: 389-392. Scottish Ornithologists’ Club, Aberlady.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

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Lesser black-backed gull (breeding)

1 Introduction

Lesser black-backed gull (breeding) is a regularly occurring migratory species. No marine proposed SPAs have been identified for lesser black-backed gull (breeding) in the Scottish pSPA network.

2 Species account

Table 1 Summary of status of lesser black-backed gull (breeding)

Species status Score Notes

GB marine Widespread Lesser black-backed gull (breeding) have a widespread distribution in the GB marine environment distribution (JNCC range score 94.8%1). Modelling of boat-based and aerial survey data across UK waters shows moderate densities in nearshore waters around much of GB (Bradbury et al, 2017), The generally higher densities off western coasts reflect the distribution of colonies (Mitchell et al, 2004). Significance of Low Coastal breeding lesser black-backed gulls are widely distributed around GB but with significant Scotland’s seas concentrations in the Firths of Forth and Clyde, in West Wales and the Severn and East Anglia. in GB context (Mitchell et al, 2004). In 1998-2002, 24.4% of coastal breeding lesser black-backed gulls in GB were found in Scotland. GB contribution High The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 117,000 pairs, equivalent to 65.4% of the biogeographic population (Larus population fuscus graellsii NW & W Europe, Greenland and Iceland) estimated at 179,000 pairs (Mitchell et al 2004).

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European Least The global and European conservation status for lesser black-backed gull is Least Concern (BirdLife population Concern International, 2015, 2016). conservation status Species status summary and The European population status of lesser black-backed gull (non-breeding) is considered Least assessment of level of Concern although GB is of High importance to the biogeographic population of this regularly representation in Scottish SPA occurring migratory species. Lesser black-backed gull (breeding) have a widespread distribution in network. GB waters with around a quarter of the breeding population in Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of lesser black-backed gull (breeding) in Europe is Low.

This assessment indicates a presumption in favour of lesser black-backed gull (breeding) being represented at least once but no more than twice within Scottish SPA network.

Table 2 Vulnerability of lesser black-backed gull (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium to high impacts on threats and relevant populations of lesser black-backed gull (breeding) (Furness, 2016). These include changes to fisheries pressures management aimed at reducing levels of fisheries discards (Dunn 1997, Camphuysen 2013), collision with offshore wind turbines (Furness et al 2013), culling (Ross-Smith et al 2014) and predation caused by invasive/non-native species (e.g. mink; Craik 2000-2002). Other pressures and threats include changes to refuse disposal practices (e.g. closure of landfill sites and the covering of waste) (Barcena et al 1984, Olsen and Larsson 2003, Mitchell et al 2004), poisoning from organochlorine pollution (Bustnes et al 2006) and potential contraction of botulism at landfill sites (Mitchell et al 2004).

The potential impacts of climate change on lesser black-backed gull are unclear (Pearce-Higgins et al 2011), although one model suggest populations will decline in the UK as a result of climate change (Russell et al 2015). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species populations providing better opportunities for sustaining diversity (SNH 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH 2016).

Lesser black-backed gull (breeding) populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions should be considered.

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3 Summary

The species assessment indicates a presumption in favour of lesser black-blacked gull (breeding) being represented at least once but no more than twice within Scottish SPA network.

No marine proposed SPAs have been identified for lesser black-blacked gull (breeding) in the Scottish pSPA network.

The number and distribution of marine proposed sites for lesser black-blacked gull (breeding) in the Scottish pSPA network is below the minimum level of representation indicated by the species assessment (Table 1).

Lesser black-backed gull are omnivorous, opportunistic feeders that forage extensively at sea. The species diet consists of small fish (especially Baltic herring Clupea harengus), aquatic and terrestrial invertebrates (e.g. beetles, flies and larvae, ants, moths, grasshoppers, crustaceans, molluscs, segmented worms and starfish), bird eggs and nestlings, carrion, offal, rodents, berries and grain. It often follows fishing fleets, feeding on discarded bycatch. The species uses both marine and terrestrial habitats for foraging (BirdLife International 2018).

Lesser black-backed gull (breeding) are vulnerable to a range of anthropogenic pressures, some of which exist at the wider ecosystem level and are therefore unlikely to be most appropriately managed through site-based protection (e.g. reduction of fishery discards) (Furness, 2016). However, some anthropogenic pressures (e.g. collision as a result of offshore wind farm developments) could be managed through provision of site-based protection encompassing supporting habitats (e.g. foraging locations). Management of pressures including culling and invasive predators could be achieved through management at breeding sites. Analysis of ESAS data did not detect any lesser black-backed gull (breeding) hotspots that satisfied both population and regularity site-selection criteria to support inclusion in the Scottish pSPA network (Kober et al, 2010).

4 Conclusion

SPA provision is not considered an appropriate conservation measure for lesser black- backed gull (breeding) due to the widely dispersed and unpredictable nature of their distribution and highest densities being located off England and Wales.

5 References

Barcena, F., Teixeira, A.M. & Bermejo, A. 1984. Breeding seabird populations in the Atlantic sector of the Iberian Peninsula. In: Croxall, J.P., Evans, P.G.H. & Schreiber, R.W. (eds.). Status and Conservation of the World's Seabirds, pp. 335-345. International Council for Bird Preservation.

BirdLife International, 2015. Larus fuscus. The IUCN Red List of Threatened Species. e.T22694373A60085745.

BirdLife International, 2016. Larus fuscus. The IUCN Red List of Threatened Species. e.T22694373A86719789. http://dx.doi.org/10.2305/IUCN.UK.2016- 3.RLTS.T22694373A86719789.en.

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BirdLife International, 2018. Species factsheet: Larus fuscus. http://www.birdlife.org

Bradbury, G., Shackshaft, M., Scott-Hayward, L., Rexstad, E., Miller, D. & Edwards, D. 2017. Risk assessment of seabird bycatch in UK waters. Unpublished report to Defra. Defra Project: MB0126. OFFICIAL SENSITIVE.

Bustnes, J.O. 2006. Environmental pollutants in endangered vs. increasing subspecies of the lesser black-backed gull on the Norwegian Coast. Environmental Pollution, 144, 893- 901.

Camphuysen, C.J. 2013. A historical ecology of two closely related gull species (Laridae): multiple adaptations to a man-made environment. PhD thesis, University of Groningen.

Craik 2000-2002. Unpublished mink-seabird project reports cited in Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. 2004. Seabird populations of Britain & Ireland. Poyser, London.

Dunn, E. 1997. Sustainable fisheries and seabirds. RSPB Conservation Review, 11, 44-50. del Hoyo, J., Elliott, A. & Sargatal, J. 1996. Handbook of the Birds of the World, vol. 3: Hoatzin to Auks. Lynx Edicions, Barcelona, Spain.

Furness, R.W., Ensor, K. & Hudson, A.V. 1992. The use of fishery waste by gull populations around the British Isles. Ardea, 80, 105-113.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Nager, R.G. & O'Hanlon, N.J. 2016. Changing Numbers of Three Gull Species in the British Isles. Waterbirds, 39, (Special Publication 1): 15-28.

Olsen, K. M. & Larsson, H. 2004. Gulls of Europe, Asia and North America. Christopher Helm, London.

Ross-Smith, V.H., Robinson, R.A., Banks, A.N., Frayling, T.D., Gibson, C.C. & Clark, J.A. 2014. The lesser black-backed gull Larus fuscus in England: how to resolve a conservation conundrum. Seabird, 27, 41-61.

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SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wilhelm, S.I., Rail, J.-F., Regular, P. M., Gjerdrum, C. & Robertson, G.J. 2016. Large-scale changes in abundance of breeding Herring Gulls (Larus argentatus) and Lesser black- backed gulls (Larus marinus) relative to reduced fishing activities in southeastern Canada. Waterbirds, 39, (sp1): 136-142.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8.

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Lesser black-backed gull (non-breeding)

1. Introduction

Lesser black-backed gull (non-breeding) is a regularly occurring migratory species. No marine proposed SPAs have been identified for lesser black-backed gull (non-breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of lesser black-backed gull (non-breeding)

Species’ status Score Notes

GB marine Restricted Restricted distribution in the GB marine environment (JNCC range score 66%1). The highest distribution densities modelled from boat-based and aerial survey data across UK waters were off the south-west

coasts of England and Wales (Bradbury et al ,2017; Kober et al, 2010). Significance of Low Burton et al (2013)2 estimates that 6,510 (5,742 – 7,294) lesser black-backed gulls winter in Scotland Scotland’s seas representing c. 8% of the best available estimate of birds overwintering in the UK3 (80,473 in GB context individuals; Furness, 2015).

Using the Burton et al (2013) estimate of 124,654 (118,055 – 131,148) individuals wintering in GB, c. 5% of the GB population winter in Scotland. GB contribution High The best available estimate of the UK wintering population of this regularly occurring migratory species to biogeographic is 80,473 (Furness, 2015), which is approximately 34% of the biogeographic population (with population connectivity to UK waters) estimated to be 235,000 birds (Furness, 2015). However, 360,787 – 372,311 birds may move through UK waters during migration (Mar-Apr, Aug-Oct; Furness, 2015).

1 Derived from the distribution models in Bradbury et al (2017)) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Data are calculated from counts of birds wintering in terrestrial and near-shore coastal waters; birds roosting offshore or not visible from land are not been included, which therefore may underestimate populations. 3 Furness (2015) provides UK reference populations rather than at a GB scale. Figures include consideration of counts of birds at sea, as well as roosting or near to shore observations. 218

There is moderate to high uncertainty associated with the Furness (2015) figures, which may be more than 50% less or 80% greater. A measure of uncertainty is indicated in the range associated with the Burton et al (2013) estimates.

Lesser black-backed gull breeds from the central-north of Russia, around Scandinavia, Germany, Belgium, the Netherlands and northern United Kingdom to Iceland. It also breeds year-round on the coast of Portugal, southern Ireland, the United Kingdom and northern France, and one seasonally breeding population is found in north-east Spain. Seasonal breeders disperse widely, expanding its range to include the entire North Sea coast, much of the Mediterranean, Black Sea and Caspian Sea coasts, the northern and eastern coasts of Africa (including rivers inland), and around the Arabian Peninsula to north-west India (del Hoyo et al, 1996). European Least The global and European conservation status for lesser black-backed gull is Least Concern (BirdLife population Concern International, 2015 & 2016). conservation status Species’ status summary and The European population status of lesser black-backed gull (non-breeding) is considered Least assessment of level of Concern although GB is of High importance to the biogeographic population of this regularly occurring representation in Scottish migratory species. Lesser black-backed gull (non-breeding) have a restricted distribution at sea, with SPA network. the highest densities off the south-west coasts of England and Wales (Bradbury et al, 2017; Kober et al, 2010). Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of lesser black-backed gull (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of lesser black-backed gull (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of lesser black-backed gull (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of lesser black-backed gull (non-breeding) (Furness, 2016). These include changes to fisheries pressures management aimed at reducing levels of fisheries discards (Dunn, 1997; Bicknell et al, 2013; Camphuysen, 2013) and collision with offshore wind turbines (Furness et al, 2013). Other pressures and threats include changes to refuse disposal practices (e.g. closure of landfill sites and the covering of waste) (Barcena et al, 1984; Olsen and Larsson, 2003; Mitchell et al, 2004), poisoning from organochlorine pollution (Bustnes et al, 2006) and contraction of botulism at landfill sites (Mitchell et al, 2004). 219

The potential impacts of climate change on lesser black-backed gull are unclear (Pearce-Higgins et al, 2011), although one model suggest populations will decline in the UK as a result of climate change (Russell et al, 2015). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Lesser black-backed gull (non-breeding) populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication in the network could be considered.

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3. Summary

The species assessment indicates there is an expectation of lesser black-backed gull (non- breeding) being represented once or twice in the Scottish SPA network.

No marine proposed SPAs have been identified for lesser black-blacked gull (non-breeding) in the Scottish pSPA network.

The number and distribution of marine proposed sites for lesser black-blacked gull (non- breeding) in the Scottish pSPA network is below the minimum level of representation indicated by the species assessment (Table 1).

Lesser black-backed gull (non-breeding) are vulnerable to a range of anthropogenic pressures, most of which exist at the wider ecosystem level and are therefore unlikely to be most appropriately managed through site-based protection (e.g. reduction of fishery discards) (Furness, 2016). However, some anthropogenic pressures (e.g. collision as a result of offshore wind farm developments) could be managed through provision of site- based protection encompassing supporting habitats (e.g. foraging locations). Analysis of ESAS data did not detect any lesser black-backed gull (non-breeding) hotspots that satisfied both population and regularity site-selection criteria to support inclusion in the Scottish pSPA suite (Kober et al, 2010). This reflects the winter distribution, with the highest densities found off the south-west coasts of England and Wales (Bradbury et al, 2017; Kober et al, 2010).

4. Conclusion

SPA provision is not considered an appropriate conservation measure for lesser black- backed gull (non-breeding) in Scotland due to the widely dispersed and unpredictable nature of their distribution and highest densities being located off England and Wales.

5. References

Barcena, F., Teixeira, A. M., & Bermejo, A. 1984. Breeding seabird populations in the Atlantic sector of the Iberian Peninsula. In: Croxall, J.P., Evans, P.G.H. & Schreiber, R.W. (eds.), Status and Conservation of the World's Seabirds, pp. 335-345. International Council for Bird Preservation.

BirdLife International, 2015. Larus fuscus. The IUCN Red List of Threatened Species 2015: e.T22694373A60085745.

BirdLife International, 2016. Larus fuscus. The IUCN Red List of Threatened Species 2016: e.T22694373A86719789. http://dx.doi.org/10.2305/IUCN.UK.2016- 3.RLTS.T22694373A86719789.en.

BirdLife International, 2018. Species factsheet: Larus fuscus. http://www.birdlife.org

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Bustnes, J.O. 2006. Environmental pollutants in endangered vs. increasing subspecies of the lesser black-backed gull on the Norwegian Coast. Environmental Pollution, 144, 893- 901.

Furness, R.W., Ensor, K. & Hudson, A.V. (1992). The use of fishery waste by gull populations around the British Isles. Ardea, 80, 105-113.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Nager, R.G. and O'Hanlon, N.J.2016. Changing Numbers of Three Gull Species in the British Isles Waterbirds, 39 (Special Publication 1): 15-28.

Olsen, K. M.; Larsson, H. 2004. Gulls of Europe, Asia and North America. Christopher Helm, London.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wilhelm, S.I., Rail, J.-F., Regular, P.M., Gjerdrum, C. & Robertson, G.J. 2016. Large-scale changes in abundance of breeding Herring Gulls (Larus argentatus) and Lesser black- backed gulls (Larus marinus) relative to reduced fishing activities in southeastern Canada. Waterbirds, 39, (sp1): 136-142.

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Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8.

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Little auk (non-breeding)

1. Introduction

Little auk is a regularly occurring migratory species. No marine proposed SPAs have been identified for little auk (non-breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of little auk (non-breeding).

Species’ status Score Notes

GB marine Widespread Little auk have a widespread distribution in the GB marine environment (JNCC range score 99.8%1). distribution The highest densities modelled from boat-based and aerial survey data across UK waters were

restricted to the Firth of Forth and the inner Moray Firth, extending into the centre of the northern North Sea to the east of Scotland and north-east England. Densities could not be modelled for the majority of England, Wales and Northern Ireland (Bradbury et al, 2017), although the distribution complies with that described in Stone et al 1995. Kober et al (2010) indicate that Dogger Bank is also an important area for little auk (non-breeding), with hotspots identified primarily in pelagic waters, namely in the centre of the North Sea. The northern North Sea is thought to be a major wintering area, with up to a million birds present (Zonfrillo, 2007). Significance of Moderate Zonfrillo (2007) suggests 100-35,000 little auks occur in Scottish offshore waters during winter, Scotland’s seas (uncertain) although their small size and offshore habitats make it challenging to establish the species’ true in GB context abundance in Scottish waters, hence the huge uncertainty in the Scottish population estimate. Little information is available on the distribution and movements of wintering little auk (Fort et al, 2013) and there is no UK or GB population estimate for this species. GB contribution Low The best available estimate of the Scottish wintering population for this regularly occurring migratory to biogeographic species is 100-35,000 birds (Zonfrillo, 2007), which is approximately <0.001-0.4% of the very large population biogeographic population (European) estimated to be 9,200,000-82,000,000 mature individuals (BirdLife International, 2015a). There is no GB or UK population estimate for this species. The global

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population is estimated to be 16,000,000-36,000,000 birds (del Hoyo et al 1996) although this is likely an underestimate (BirdLife International 2018). There is high uncertainty around all estimated population figures for this species.

Little auk have an extremely large population and a large range. The species breeds from the eastern Canadian coast to the Russian Arctic (Fort et al, 2013). Little auk winter in the low Arctic from Newfoundland across the Atlantic to Norway, but also south to Scotland and New England, infrequently reaching as far south as Florida and northern France (Zonfrillo, 2007). European Least The global and European conservation status for little auk is Least Concern (BirdLife International, population Concern 2015b, 2018). conservation status Species’ status summary and Non-breeding little auk in Scotland are of low importance to the very large biogeographic population of assessment of level of this regularly occurring migratory species and their European population status is Least Concern. They representation in Scottish have a widespread distribution in UK waters. The species is highly pelagic, but within GB territorial SPA network. waters Scotland is thought to be of moderate importance. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of little auk (non- breeding) in Europe is Very low.

This assessment indicates there is no expectation of little auk (non-breeding) being represented in the Scottish SPA network.

Table 2 Vulnerability of little auk (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is no evidence of activities in UK waters generating pressures or threats likely to have medium or high impacts threats and on relevant populations of little auk (non-breeding) (Furness, 2016). However, lower level impacts include accidental pressures bycatch in fishing nets (Bradbury et al, 2017), disturbance caused by increased shipping activity and oil spills (Fort et al, 2013).

Little auks in their Arctic breeding grounds appear to be adapting to impacts of climate change (Grémillet et al, 2012) but changes in sea ice extent may impact winter distribution (Fort et al, 2013).

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3. Summary

The species assessment indicates there is no expectation of little auk (non-breeding) being represented in the Scottish SPA network.

No sites have been identified for little auk (non-breeding) in the Scottish pSPA network which is consistent with the species assessment (Table 1).

Little auk (non-breeding) are vulnerable to anthropogenic pressures that exist at the wider ecosystem level and are therefore unlikely to be most appropriately managed through site- based protection (e.g. oil spills). In addition, little auk (non-breeding) has a widely dispersed and unpredictable distribution meaning that a significant marine SPA provision is unrealistic.

4. Conclusion

The species assessment confirms that SPA provision is not considered an appropriate conservation measure for little auk (non-breeding) due to the widely dispersed and unpredictable nature of their distribution.

5. References

BirdLife International, 2015a. European Red List of Birds: Alle alle (Little auk). Supplementary Material. Luxembourg: Office for Official Publications of the European Communities. http://datazone.birdlife.org/userfiles/file/Species/erlob/supplementarypdfs/22694837_alle_all e.pdf

BirdLife International, 2015b . Alle alle. The IUCN Red List of Threatened Species 2015: e.T22694837A60108138.

BirdLife International, 2017. Alle alle (amended version of 2016 assessment). The IUCN Red List of Threatened Species 2017: e.T22694837A110636471. http://dx.doi.org/10.2305/IUCN.UK.2017-1.RLTS.T22694837A110636471.en.

BirdLife International, 2018. Species factsheet, Alle alle. http://www.birdlife.org

Bradbury, G., Shackshaft, M., Scott-Hayward, L., Rexstad, E., Miller, D. & Edwards, D. 2017. Risk assessment of seabird bycatch in UK waters. Report to Defra. Defra Project: MB0126. http://sciencesearch.defra.gov.uk/Document.aspx?Document=14236_MB0126Riskassessm entofseabirdbycatchinUKwaters.pdf del Hoyo, J., Elliott, A., & Sargatal, J. 1996. Handbook of the Birds of the World, 3. Hoatzin to Auks. Lynx Edicions, Barcelona.

Fort, J., Moe, B., Strøm, H., Grémillet, D., Welcker, J., Schultner, J., Jerstad, K., Johansen, K. L., Phillips, R. A. & Mosbech, A. 2013. Multicolony tracking reveals potential threats to little auks wintering in the North Atlantic from marine pollution and shrinking sea ice cover. Diversity and Distributions, 19, 1322–1332.

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Grémillet, D., Welcker, J., Karnovsky, N.J., Walkusz, W., Hall, M. et al. 2012. Little auks buffer the impact of current Arctic climate change. Marine Ecology Progress Series, Inter- Research, 454, pp.197-206.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Zonfrillo, B. 2007. Little Auk. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 2: 863 – 866. Scottish Ornithologists’ Club, Aberlady.

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Little gull (non-breeding)

1. Introduction

Little gull is an Annex 1 species. Little gull (non-breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for little gull (non-breeding)

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2. Species account

Table 1 Summary of status of little gull (non-breeding).

Species’ status Score Notes

GB marine Highly Highly restricted distribution in the GB marine environment (JNCC range score 2.4%1). The distribution restricted highest densities modelled from boat-based and aerial survey data across UK waters were on the south-east coast of England, in the Firth of Forth and mouth of the river Tay, over Dogger Bank,

along the north-west coast of England off Liverpool and Blackpool, and in Cardigan Bay (Bradbury et al, 2017). This aligns with data presented in Kober et al (2010), with some additional small hotspots identified on the north-east coast of England, around the Isle of Man, and a hotspot at sea off the south-west tip of Cornwall. Significance of High Scott (2007) estimated that 20-400 little gulls winter in Scotland. The best available estimate2 of the Scotland’s seas number of little gulls overwintering in GB waters is 300-800 individuals (Lack 1986). However, Scott in GB context (2007) suggests the Lack 1986 figures are underestimates. For context, survey data collected in the Outer Firth of Forth and St Andrews Bay Complex pSPA recorded 317 little gull in 2003/04 (Lawson et al, 2015).

As a result of their offshore nature there is a lack of knowledge regarding wintering little gull populations in GB and Scotland. Counts of little gull vary considerably and usually occur when adverse weather brings birds within proximity to the coast. GB contribution Medium The best available estimate of the GB wintering population of this Annex 1 species is 300-800 birds to biogeographic (Lack, 1986) (likely an underestimate; Scott, 2007) which is <1-2% of the biogeographic population population (European) estimated to be 47,400-90,500 birds (BirdLife International, 2015).

Little gull breed in northern Scandinavia, the Baltic republics and western Russia to western Siberia, in eastern Siberia, and in the Great Lakes of North America. The species’ wintering range includes most of the Mediterranean, Black Sea and Caspian Sea coastlines, the Atlantic coast of Europe, including the North Sea, and the north-west coast of the USA (BirdLife International, 2018).

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European Near The European conservation status for little gull is Near Threatened (BirdLife International, 2015), population Threatened whilst the global conservation status is Least Concern (BirdLife International, 2016). conservation The different conservation statuses are attributed to little gull populations undergoing rapid declines status in its European breeding range since the 2000s. Species’ status summary and The European population status of little gull (non-breeding) is considered Near Threatened. GB is assessment of level of of medium importance to the biogeographic population of this Annex 1 species. Little gull (non- representation in Scottish SPA breeding) have a highly restricted distribution at sea, with the highest densities on the south-east network. coast of England, in the Firth of Forth and mouth of the River Tay, over Dogger Bank, along the north-west coast of England off Liverpool and Blackpool, and in Cardigan Bay (Bradbury et al, 2017). Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of little gull (non-breeding) in Europe is High.

This assessment indicates there is an expectation of little gull (non-breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of little gull (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is no evidence of activities in UK waters generating pressures or threats likely to have high or medium impacts threats and on relevant populations of little gull (non-breeding) (Furness, 2016). However, lower level impacts include collision pressures with offshore wind turbines (Bradbury et al, 2014), depletion of prey resources (Mendel et al, 2008), habitat degradation, including changes in hydrographic conditions (Scott, 2007), oil spills (Mendel et al, 2008), and accidental bycatch in fishing gear (Žydelis et al, 2013, Bradbury et al, 2017).

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3. Contribution to Scottish SPA network

This section considers the occurrence of little gull (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Little gull (non-breeding) are being considered for inclusion at one marine proposed SPA and are not represented in existing terrestrial or estuarine SPAs.

Table 3 Summary of occurrence of little gull (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports c. >50 Little gull (non-breeding) is Provides the only example for this No known linkages. Forth & St individuals. represented within one species in Scotland. Andrews Bay This equates to c. proposed SPA. Complex 6-17% of the best available estimate There are no existing SPAs for of the GB non- this species in Scotland. breeding No sites were identified in population (Lack OSPAR Region III. 1986).

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4. Summary

The species assessment (Table 1) indicates there is an expectation of little gull (non- breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

The proposed Scottish SPA network includes one marine pSPA for little gull (non-breeding) supporting c. >50 individuals (c. 6-17% of the GB non-breeding population). The pSPA occurs in OSPAR Region II. No sites were identified in OSPAR Region III.

The number of marine proposed sites for little gull (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation indicated by the species assessment (Table 1). However, the species has a very restricted distribution and only one hotspot holding qualifying numbers (50 or more) little gull (non- breeding) has been identified in Scotland’s seas (Kober et al, 2010; Lawson et al, 2015; Bradbury et al, 2017).

Little gull (non-breeding) populations have not been identified as vulnerable to anthropogenic threats or pressures at sea that may have medium or high impacts (Furness, 2016). Threats and pressures at the individual level for which the population level effects are not fully known include collision with offshore wind turbines (Bradbury et al, 2014), depletion of prey resources (Mendel et al, 2008), habitat degradation, including changes in hydrographic conditions (Scott, 2007), oil spills (Mendel et al, 2008), and accidental bycatch in fishing gear (Žydelis et al, 2013, Bradbury et al, 2017).

There are no existing terrestrial SPAs for this species in Scotland and therefore no known linkages.

5. Conclusion

The number and distribution of marine proposed SPAs for little gull (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of little gull (non-breeding) in Europe.

The Scottish marine SPA network includes the only locations (the Firth of Forth and mouth of the River Tay) where small but regular numbers of non-breeding little gull occur in Scottish inshore areas. No further SPA provision is considered necessary for little gull (non-breeding) however, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing little gull (non-breeding) populations at the wider seas/ecosystem level.

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6. References

BirdLife International, 2015. Hydrocoloeus minutus. The IUCN Red List of Threatened Species 2015: e.T22694469A60090613.

BirdLife International, 2016. Hydrocoloeus minutus. The IUCN Red List of Threatened Species 2016: e.T22694469A89503500. http://dx.doi.org/10.2305/IUCN.UK.2016- 3.RLTS.T22694469A89503500.en.

BirdLife International, 2018. Species factsheet, Hydrocoloeus minutus. http://www.birdlife.org

BirdLife International, 2018. IUCN Red List for birds. http://www.birdlife.org

Bradbury, G., Trinder, M., Furness, B., Banks, A.N., Caldow, R.W.G. & Hume, D. 2014. Mapping Seabird Sensitivity to Offshore Wind Farms. PLoS ONE, 9, (9): e106366.

Lack, P.C. (1986). The atlas of wintering birds in Britain and Ireland. Poyser. London.

Scott, C. 2007. Little Gull. In Forrester, R.W. & Andrews, I.J. (eds.). The Birds of Scotland, Vol. 1: 745 – 748. Scottish Ornithologists’ Club, Aberlady.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8.

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Little tern (breeding)

1. Introduction

Little tern is an Annex 1 species. Little tern (breeding) is being considered for inclusion within a proposed marine extension to one existing SPA. This is shown in Figure 1.

Figure 1 Map showing proposed marine extension for little tern (breeding)

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2. Species account

Table 1 Summary of status of little tern (breeding)

Species’ status Score Notes

GB marine Highly Breeding little terns forage in shallow waters in close proximity to their colonies, typically within 2.5km distribution restricted seaward and 4km along the shoreline (Parsons et al, 2015; Thaxter et al, 2012). This is reflected in the observed at-sea distribution in UK waters in the summer months (Bradbury et al, 2017). Significance of Low Little terns breed on sand and shingle beaches and the majority of colonies in GB, comprising over Scotland’s seas 75% of the population, are on the east and south coasts of England, from Northumberland to Dorset in GB context (Mitchell et al, 2004). The Seabird 2000 national census of breeding seabirds in Britain and Ireland found a total GB population of 1,950 pairs of which 330 (17%) were in Scotland (Mitchell et al, 2004). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this Annex 1 species is 1,950 to biogeographic pairs which represents 8.6 – 11.2% of the biogeographic population (albifrons subspecies Europe population north of Mediterranean) estimated at 17,000 - 22,000 pairs (Mitchell et al, 2004).

Little tern colonies are scattered along the coasts and inland parts of Europe, parts of Africa, much of western, central and the extreme east and south of Asia, and in northern parts of Australasia. Migratory individuals expand the range to include most of the coast of Africa, the Arabian Peninsula, the western coast of India and most of the waters of south-east Asia and Australasia, including New Zealand (BirdLife International, 2018). European Depleted The European conservation status for little tern is Depleted and the global conservation status is population Least Concern (BirdLife International, 2017 & 2018). conservation status This reflects previous declines in the European population and the large size (c.190,000-410,000 individuals) and extensive range of this species globally. Species’ status summary and The European population status of little tern (breeding) is considered Depleted and GB is of Medium assessment of level of importance to the biogeographic population of this Annex 1 species. Little tern (breeding) have a representation in Scottish highly restricted distribution at sea, with the highest densities in eastern and southern England where SPA network. the majority of the GB breeding population is located.

Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of little tern (breeding) is Medium.

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This assessment indicates there is an expectation of little tern (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of little tern (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have either threats and high or medium impacts on relevant populations of breeding little tern (Furness, 2016). In particular, little tern are pressures highly dependent for successful breeding on availability of suitable prey fish, such as juvenile sandeels or herring, in close proximity to their colonies. Little tern populations can therefore be impacted by pressures including climate change (Arnott et al, 2002), commercial fisheries (Furness, 2002) or construction activities (Perrow et al, 2011) that affect prey fish distribution or stocks. The foraging success of little terns is affected by water turbidity (Brenninkmeijer et al, 2002) and they appear to avoid foraging in areas where turbidity is increased (e.g. by shipping traffic) (Pavia et al, 2007). They may therefore be sensitive to such that activities such as dredging that impact turbidity (Cook and Burton, 2010) but the significance of any impacts on breeding populations is undocumented.

In addition to pressures in their foraging grounds, little terns are also vulnerable to human disturbance, mammalian and avian predators, and sea level rise and storm surges at their nest sites, which are typically close to the high tide mark on accessible sand and shingle beaches (Ratcliffe et al, 2008).

As outlined above, little tern colonies may be vulnerable to both direct and indirect impacts of climate change, but it is predicted that overall UK populations of little tern are likely to increase by 2050 under a medium emissions scenario (Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Little tern populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

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3. Contribution to Scottish SPA network

This section considers the occurrence of little tern (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Little tern (breeding) is being considered for inclusion in a proposed marine extension to the existing Ythan Estuary, Sands of Forvie and Meikle Loch SPA, where it is a feature of the breeding colony. The proposed marine extension encompasses the foraging area used by breeding terns from the colony SPA. Little tern is also a feature at three other existing colony SPAs, one of which has a marine extension for various cliff-nesting seabird species for maintenance behaviours such as preening, loafing and roosting.

Table 3 Summary of occurrence of little tern (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Ythan Estuary, Supports c. 2% of Little tern is represented within Provides only example Birds foraging in the Sands of Forvie and the GB breeding one proposed SPA and 4 existing for this species in proposed marine extension Meikle Loch (marine population. colony SPAs, one of which has a Scotland. are within foraging range of extension) marine extension. However, little the breeding colony at the tern is not the species existing Ythan Estuary, determining the extension. Sands of Forvie and Meikle No sites were identified in Loch SPA (Parsons et al, OSPAR Region III. 2015).

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4. Summary

The species assessment (Table 1) indicates there is an expectation of little tern (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The Scottish SPA network includes one proposed marine extension to an existing colony SPA for little tern (breeding) and three other existing estuarine/coastal SPAs. The proposed marine extension in OSPAR Region II supports an estimated 2% of the GB breeding population. The proposed marine extension does not reflect the full geographic range and variation of little tern (breeding) in Scotland as indicated by the 1998-2002 census (Mitchell et al, 2004). However, it is adjacent to the only one of four little tern colony SPAs in Scotland assessed as regularly occupied in the 2000s (Parsons et al, 2015).

The number and distribution of marine proposed SPAs for little tern (breeding) in the Scottish network, as summarised above and in Table 3, is below the minimum indicated by the species assessment (Table 1).

There are no pSPAs in OSPAR Region III, which includes waters used by foraging little terns from colonies in the Outer and Inner Hebrides. This apparent under-representation reflects the approach to identification of marine SPAs for little terns which focused on characterising the foraging areas used by little terns from existing colony SPAs. There are four such colony SPAs in Scotland, with two in each of OSPAR Regions II and III. However, only the colony at Ythan Estuary, Sands of Forvie and Meikle Loch SPA has been recently regularly occupied by qualifying numbers of breeding little terns and consequently the remaining three colonies were not included in the process to identify marine sites (Parsons et al, 2015).

Replication in the network would be desirable because little tern is an Annex 1 species and there is evidence that little tern (breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Many of these threats and pressures require management at an ecosystem or broader scale. Site-based protection of core foraging areas however complements wider measures and is considered an appropriate conservation measure to enhance resilience of little tern (breeding).

The proposed Ythan Estuary, Sands of Forvie and Meikle Loch (marine extension) is within mean maximum foraging range of the adjacent colony SPA, and encompasses the core sea area used for foraging by breeding birds from this colony (Parsons et al, 2015). Inclusion of the proposed marine extension in the network provides added conservation value by safeguarding marine habitats supporting prey species used by little tern (breeding) from existing colony SPAs.

5. Conclusion

The number and distribution of marine proposed SPAs for little tern (breeding) is fully justified both in terms of meeting the UK SPA Selection guidelines and the relative value of protected areas in Scotland’s marine environment to the conservation of little tern (breeding) in Europe.

SPA provision or additional site-based and/or alternative conservation measures are recommended for little tern (breeding). Potentially suitable additional sites could probably be identified with relatively little additional work.

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6. References

Arnott, S.A. & Ruxton, G.D. 2002. Sandeel recruitment in the North Sea: demographic, climatic and trophic effects. Marine Ecology Progress Series, 238, 199-210

Brenninkmeijer, A., Stienen, E. W. M., Klaassen, M. and Kersten, M. 2002. Feeding ecology of wintering terns in Guinea-Bissau. Ibis, 144, 602–613

BirdLife International, 2018. Species factsheet, Sternula albifrons. http://www.birdlife.org

Furness, R.W. 2002. Management implications of interactions between fisheries and sandeel-dependent seabirds and seals in the North Sea. ICES Journal of Marine Science, 59, 261-269.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Paiva, V.H., Ramos, J.A., Martins, J., Almeida A. & Carvalho A. 2007. Foraging habitat selection by Little Terns Sternula albifrons in an estuarine lagoon system of southern Portugal. Ibis 150, 18–31

Parsons, M., Lawson, J., Lewis, M., Lawrence, R. & Kuepfer, A. 2015. Quantifying foraging areas of little tern around its breeding colony SPA during chick-rearing. JNCC Report No. 548. Joint Nature Conservation Committee, Peterborough.

Pearce-Higgins, J.W., Johnston, A., Ausden, M., Dodd, A., Newson, S.E., Ockendon, N., Thaxter, C.B., Bradbury, R.B., Chamberlain, D.E, Jiguet, F., Rehfisch, M.M. &

Perrow, M.R., Gilroy, J.J., Skeate, E.R. & Tomlinson, M.R. 2011. Effects of the construction of Scroby Sands offshore wind farm on the prey base of Little tern Sternula albifrons at its most important UK colony. Marine Pollution Bulletin, 62, 1661-1670.

Ratcliffe, N., Schmitt, S., Mayo, A., Tratalos, J. & Drewitt, A. 2008. Colony habitat selection by little terns Sternula albifrons in East Anglia: implications for coastal management. Seabird, 21, 55-63

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SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Thomas, C.D. 2011. Final Report to the Climate Change Impacts on Avian Interests of Protected Area Networks (CHAINSPAN) Steering Group. BTO Report to DEFRA. http://randd.defra.gov.uk/Document.aspx?Document=9962_CHAINSPANFINALREPORT.pdf

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Long-tailed duck (non-breeding)

1. Introduction

Long-tailed duck is a regularly occurring migratory species. Long-tailed duck (non-breeding) is being considered for inclusion within six marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for long-tailed duck (non-breeding)

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2. Species account

Table 1 Summary of status of long-tailed duck (non-breeding)

Species’ status Score Notes

GB marine Restricted Long-tailed duck (non-breeding) have a restricted distribution in the GB marine environment (JNCC distribution range score 11.6%1 and recorded in an average of 17.4% of coastal core WeBS count sectors counted between 2011 and 20152). Significance of High Major concentrations of long-tailed duck are almost entirely confined to Scottish coastal (Austin et al, Scotland’s seas 2017) and inshore waters, particularly in east coast Firths and in the Northern and Western Isles in GB context (Balmer et al, 2014; Bradbury et al, 2017). GB contribution Low The GB wintering population of this regularly occurring migratory species is 11,000 birds (Musgrove et to biogeographic al, 2013) which represents approximately 0.7% of the very large biogeographic (North-West population Europe) population estimated at 1,600,000 birds (Wetlands International, 2015 & 2018). More recent sources (e.g. Lawson et al, 2015; Austin et al, 2017) suggest that the GB wintering population may be somewhat larger than currently estimated, although still relatively low compared with the total in NW Europe.

Long-tailed duck have a circumpolar breeding distribution across Arctic coasts of North America, Greenland, Europe and Asian Russia migrating south to winter at sea (BirdLife International, 2017b). The GB wintering population is on the south-western edge of the NW Europe biogeographic range. The origins and migration routes of birds wintering around Britain and Ireland are poorly understood; the majority are thought to breed in northern Fennoscandia and northwest Russia, but there is very little supporting evidence (Wright et al, 2012).

1 Derived from the distribution models in Bradbury et al (2017) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Data supplied on 14 February 2018 by the British Trust for Ornithology, the Royal Society for the Protection of Birds and the Joint Nature Conservation Committee (the last on behalf of the statutory nature conservation bodies: Natural England, Natural Resources Wales and Scottish Natural Heritage and the Department of Agriculture, Environment and Rural Affairs, Northern Ireland) in association with the Wildfowl and Wetlands Trust.

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Species’ status Score Notes

European Vulnerable Both the European and global population conservation statuses are Vulnerable because of an population apparent severe decline detected in the wintering population in the Baltic Sea between the early 1990s conservation and late 2000s (BirdLife International, 2017a & b). Similar declines have been observed in Norway and status north-east Scotland (Hearn et al, 2015). Species’ status summary and The long-tailed duck (non-breeding) population wintering in Scotland’s inshore waters is of Low assessment of level of importance to the very large biogeographic population of this regularly occurring migratory species. representation in Scottish The European population status is considered Vulnerable and therefore measures to improve SPA network. conservation status are considered to be of high importance. Long-tailed duck (non-breeding) have a restricted distribution in GB inshore waters, almost entirely confined to Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of long-tailed duck (non-breeding) in Europe is Medium.

This assessment indicates there is an expectation of long-tailed duck (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of long-tailed duck (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have threats and medium impacts on relevant populations of long-tailed duck (non-breeding) (Furness, 2016). Direct mortality from pressures chemical and oil pollution, including recurrent small-scale incidents, and drowning through entanglement in gillnets are the main pressures identified in the Baltic (Hearn et al, 2015; Mendel et al, 2008) but vulnerability to bycatch in British fisheries appears relatively low (Bradbury et al, 2017).

Barrier effects and habitat loss have been documented at offshore wind farms in Sweden and Denmark (Dierschke & Garthe, 2006) and long-tailed duck exhibit a high sensitivity to visual disturbance associated with vessel movements (Jarrett et al, 2018; Mendel et al, 2008), but impacts on populations are unknown.

Long-tailed duck have been identified as vulnerable to impacts of climate change with potential for a moderate magnitude decline in the UK (Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’

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populations providing better opportunities for sustaining diversity (SNH, 2016). Marine proposed SPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Long-tailed duck populations are vulnerable to medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of long-tailed duck (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Long-tailed duck (non-breeding) are being considered for inclusion at six marine proposed SPAs and are represented in two existing estuarine/coastal SPAs.

Table 3 Summary of occurrence of long-tailed duck (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

East Mainland Supports c. 1.5% of the Long-tailed duck (non- Provides an example in No known linkages Coast, Shetland GB non-breeding breeding) are the Northern Isles and population. represented within 6 represents the northern proposed SPAs and extent of the range of this there are 3 existing species in Scotland. North Orkney Supports c. 8.5% of the estuarine/coastal SPAs Provides an example in No known linkages GB non-breeding for this species in the Northern Isles and population. Scotland. represents a core part of the range of this species in Replication of this Scotland. Scapa Flow Supports c. 12.7% of the feature in the network is Provides an example in No known linkages GB non-breeding proposed in OSPAR the Northern Isles and population. Region II. represents a core part of the range of this species in Scotland.

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Proposed SPAs Representation Replication Geographic range Linkages

Moray Firth Supports c. 45.5% of the Provides an example on No known linkages GB non-breeding the east mainland coast population. and represents a core part of the range of this species in Scotland. Outer Firth of Supports a non-breeding Provides an example on Long-tailed duck is a feature of Forth & St waterfowl assemblage, the east mainland coast the non-breeding waterbird Andrews Bay including long-tailed duck and represents the assemblage of the Firth of Forth Complex equivalent to c.17.7% of southern extent of the SPA and Firth of Tay and Eden the GB non-breeding range of this species in Estuary SPAs, both of which are population. Scotland. contiguous with this marine proposed SPA. West Coast of Supports c. 7.5% of the Provides only example on No known linkages the Outer GB non-breeding the west coast of Hebrides population. Scotland.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of long-tailed duck (non- breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes six marine pSPAs for long-tailed duck (non- breeding) that together hold up to c. 90% of the estimated GB population. Five of these pSPAs are within OSPAR Region II and the sixth is in OSPAR Region III. This reflects the geographic range of long-tailed duck (non-breeding) in Scotland from Shetland and Orkney to east coast Firths and the Western Isles. The sites also reflect the varied environments in which long-tailed ducks occur (e.g. from the exposed West Coast of the Outer Hebrides to the more sheltered waters of sites such as Scapa Flow).

The number and distribution of marine proposed sites for long-tailed duck (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, exceeds the minimum level of representation indicated by the species assessment (Table 1).

Replication in OSPAR regions overlapping the Scottish distribution of long-tailed duck (non- breeding) is considered appropriate because there is evidence that long-tailed duck (non- breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of long-tailed duck (non-breeding) to such threats and pressures and the AEWA species action plan (Hearn et al, 2015) includes as a goal “A network of protected areas, covering all important sites throughout the lifecycle, is designated and maintained”. Replication in OSPAR Region II may also address lack of replication in OSPAR Region III where there are relatively few major wintering concentrations of long-tailed duck outwith the Outer Hebrides.

There is local geographic replication within OSPAR Region II, with three pSPAs for long- tailed duck (non-breeding) in the Northern Isles; two in Orkney, at North Orkney and Scapa Flow, and one in Shetland. The East Mainland Coast, Shetland pSPA represents the northern extent of this species in GB. North Orkney pSPA and Scapa Flow pSPA represent the core part of the range of this species in Scotland together supporting around a fifth of the GB population, second only to the contribution of the Moray Firth pSPA. Of the two Orkney sites, Scapa Flow pSPA holds the third largest number of long-tailed duck (non-breeding) in the Scottish pSPA suite and North Orkney the sixth largest.

The Outer Firth of Forth and St Andrews Bay Complex pSPA is contiguous with two existing estuarine SPAs. Together these three sites encompass the full range of habitats used by long-tailed ducks within the greater Forth.

5. Conclusion

No further SPA provision in Scotland's marine environment is considered necessary for long- tailed duck (non-breeding) however, a review of the level of representation in the proposed SPA network and in particular, the Northern Isles is required by the Advisory Panel.

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6. References

Balmer, D, Gillings, S., Caffrey, B., Swann, B, Downie, I & Fuller, R. 2014. Bird Atlas 2007- 11: The Breeding and Wintering Birds of Britain and Ireland. BTO, BirdWatch Ireland, and SOC. BTO Bird Atlas Mapstore https://app.bto.org/mapstore/StoreServlet

BirdLife International (2017b) Species factsheet: Clangula hyemalis. http://www.birdlife.org

Dierschke, V & Garthe, S. 2006. Literature review of offshore windfarms with regards to seabirds. BfN-Skripten, 186, 131-198.

Hearn, R., Harrison, A. & Cranswick, P. 2015. Agreement on the Conservation of African- Eurasian Migratory Waterbirds (AEWA) - Draft International Single Species Action Plan for the Conservation of the Long-tailed Duck Clangula hyemalis 2016–2025. Adopted at 6th Session of the Meeting of the Parties in November 2015, Bonn, Germany. http://www.unep- aewa.org/en/document/draft-international-single-species-action-plan-conservation-long- tailed-duck-1

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M. 2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

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SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

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Manx shearwater (breeding)

1. Introduction

Manx shearwater is a regularly occurring migratory species. Manx shearwater (breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for Manx shearwater (breeding)

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2. Species account

Table 1 Summary of status of Manx shearwater (breeding).

Species’ status Score Notes

GB marine Moderately Manx shearwater (breeding) have a moderately restricted distribution in the GB marine environment distribution restricted (JNCC range score 79.5%1). Modelling of boat-based and aerial survey data across UK waters shows highest summer densities through the Irish Sea and off the west coast of Scotland, particularly in the vicinity of major colonies off south Wales and in the Inner Hebrides, with lesser densities in the Minch and to the west of the Outer Hebrides (Bradbury et al, 2017; Stone et al, 1995). In the late summer, notable densities also occur off the east coast of Scotland and northern England (Hall et al, 1987) including in the vicinity of the Firths of Forth and Tay (Stone et al, 1995).

The observed at-sea distribution reflects the formation of large rafts of Manx shearwaters near breeding colonies in the evenings before the birds return to their burrows at night (McSorley et al, 2008) and the importance of fronts in the Irish Sea to birds from the Welsh colonies (Shoji et al, 2015). Manx shearwaters use foraging areas both close to their breeding sites and much further out to sea (Shoji et al, 2015; Guilford et al, 2009). Significance of Moderate The breeding distribution of Manx shearwaters in GB is concentrated around two major colonies, at Scotland’s seas Rum in the Inner Hebrides and on Skokholm and Skomer in south Wales. The Scottish breeding in GB context population represents 43% of the GB total (Mitchell et al, 2004), but birds from the Welsh colonies are also known to use Scottish waters, particularly around the Clyde, during the breeding season2 and consequently the relative importance of Scotland’s seas is considered to be Moderate. GB contribution High The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 295,089 pairs, equivalent to 68.3 – 91.2% of the biogeographic population population (World) estimated at 340,000 – 410,000 pairs (Mitchell et al, 2004).

Manx shearwater breed in the north Atlantic, with major colonies on the west coasts of Scotland and Wales. Smaller numbers breed in Ireland, Faroe Islands and Iceland and the breeding range extends

1 Derived from the distribution models in Bradbury et al (2017) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 See https://insideecology.com/2017/10/16/a-summer-studying-shearwaters/

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as far as Massachusetts and Newfoundland, the Azores and the Canary Islands. Manx shearwater are transequatorial migrants wintering off the Atlantic coast of South America below the equator (BirdLife International, 2018; Mitchell et al, 2004, Guilford et al, 2009). European Least The European and global conservation status of Manx shearwater is Least Concern (Secure) population Concern (BirdLife International, 2017 & 2018). conservation status Species’ status summary and The European population status of breeding Manx shearwater is considered Least Concern (Secure) assessment of level of and GB is of High importance to the biogeographic population of this regularly occurring migratory representation in Scottish species. Manx shearwater have a moderately restricted distribution at sea in GB waters, with the SPA network. highest densities in the Irish sea and to the west of Scotland, reflecting the breeding distribution and foraging behaviour. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of Manx shearwater (breeding) in Europe is Medium

This assessment indicates there is an expectation of Manx shearwater (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of Manx shearwater (breeding) populations to anthropogenic threats and pressures.

Vulnerability to Manx shearwaters are highly vulnerable to depredation by mammalian predators at their breeding colonies, but when threats and at sea there is no specifically documented evidence of activities in UK waters generating pressures or threats likely to pressures have either high or medium impacts on relevant populations (Furness, 2016). Shearwater species are vulnerable to bycatch in longline and gillnet fisheries (Cortes et al, 2018; Tasker et al, 2000; Žydelis et al, 2013). All shearwaters are ranked as among the top 50% most sensitive species to bycatch in surface gears in fisheries operating in UK waters (Bradbury et al, 2017), but there is no empirical data on actual capture rates or evidence of impacts on populations (ibid).

The potential impacts of climate change on Manx shearwater in the UK are uncertain (Pearce-Higgins et al, 2011; Russell et al, 2015) and may include complex interactions with predators at nesting colonies (Thompson & Furness, 1991). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

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3. Contribution to Scottish SPA network

This section considers the occurrence of Manx shearwater (breeding) within the proposed SPAs and existing SPAs in Scotland. Manx shearwater (breeding) are being considered for inclusion at one marine proposed SPA and are represented in two existing colony SPAs, both of which have marine extensions for Manx shearwater maintenance behaviours.

Table 3 Summary of occurrence of Manx shearwater (breeding) within proposed SPAs in the Scottish MPA network

Proposed Representation Replication Geographic Linkages SPAs range

Outer Firth of Supports a Manx shearwater Provides only Functional linkages are unclear as this site is not in Forth & St breeding seabird (breeding) is example of this the vicinity of any major breeding colonies and Andrews Bay assemblage, represented within one species in largest numbers are present during the chick-rearing Complex including 2,885 proposed SPA and 2 Scotland. period when it is less likely that breeding birds from Manx existing SPAs, both of the nearest large colonies, over 650km distant by

shearwater3. which have marine sea to the west, would routinely use this area. The extensions for Manx Manx shearwaters in this pSPA may represent a shearwater maintenance mixture of breeding adults from distant colonies, behaviours. sabbatical or pre-breeding age birds and possibly failed breeders, with the majority being in the latter

categories after June. No sites were identified in OSPAR Region III.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of Manx shearwater (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes one marine pSPA (Outer Firth of Forth and St Andrews Bay Complex) for Manx shearwater (breeding) in OSPAR Region II holding an average of 2,885 birds4. Manx shearwater are included in the Outer Firth of Forth and St Andrews Bay Complex pSPA under site selection guideline 1.3. They form part of a regularly occurring multi-species (breeding) season seabird assemblage of over 20,000 birds and meet the threshold for inclusion as a named feature of this assemblage as they occur regularly in numbers exceeding 2000 individuals. However, Manx shearwater were not one of the main species driving identification of the assemblage feature4 and the Outer Firth of Forth and St Andrews Bay Complex site is not in the core breeding season range of Manx shearwater in Scotland (Bradbury et al, 2017). No sites have been identified in OSPAR Region III where the largest colony (Rum), holding some 40% of the GB population, and highest breeding season at-sea densities of Manx shearwaters in Scotland are found (Bradbury et al, 2017; Mitchell et al, 2004).

The number and distribution of marine proposed sites for Manx shearwater (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation anticipated by the species assessment (Table 1).

Replication in the Scottish marine pSPA network would be desirable within the species’ core range in OSPAR Region III. Manx shearwater (breeding) populations have not been identified as vulnerable to anthropogenic threats or pressures in Scottish waters (Furness, 2016). The most significant threats identified are associated with mammalian predators at breeding colonies, the impacts of which may be affected by climate change (Thompson & Furness, 1991). Two colonies in Scotland, including the largest on Rum, are already designated as (terrestrial) SPAs.

A potential Manx shearwater hotspot was identified in the vicinity of Rum through JNCC’s analysis of European Seabirds at Sea (ESAS) data but insufficient data were available to adequately test persistence of usage by qualifying numbers (Kober et al, 2010).

5. Conclusion

The number and distribution of marine proposed SPAs for Manx shearwater (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of Manx shearwater (breeding) in Europe.

Further SPA provision in OSPAR Region III or additional site-based and/or alternative conservation measures are recommended for Manx shearwater (breeding). Potentially suitable additional SPAs could probably be identified with additional targeted survey effort.

4 See the Site Selection Document at https://www.nature.scot/outer-firth-forth-and-st-andrews-bay-complex- proposed-marine-spa-supporting-documents for full details

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6. References

BirdLife International, 2018. Species factsheet, Puffinus puffinus. http://www.birdlife.org

Cortés V., García-Barcelona S. & González-Solís, J. 2018. Sex- and age-biased mortality of three shearwater species in longline fisheries of the Mediterranean. Marine Ecology Progress Series, 588, 229-241. https://doi.org/10.3354/meps12427

Guilford, T., Meade, J., Willis, J., Phillips R. A., D. Boyle, D., Roberts, S., Collett, M., Freeman, R. & Perrins, C.M. 2009. Migration and stopover in a small pelagic seabird, the Manx shearwater Puffinus puffinus: insights from machine learning. Proceedings of the Royal Society B, 276, 1215–1223 doi:10.1098/rspb.2008.1577

Hall, A.J., Tasker, M.L. & Webb, A. 1987. The marine distribution of Sooty shearwater, Manx shearwater, storm petrel and Leach's petrel in the North Sea. Seabird, 10, 69-70.

McSorley C., Wilson, L. J., Dunn, T. J., Gray, C., Dean, B. J., Webb, A. & Reid, J.B. 2008. Manx shearwater Puffinus puffinus evening rafting behaviour around colonies on Skomer, Rum and Bardsey: its spatial extent and implications for recommending seaward boundary extensions to existing colony Special Protection Areas in the UK. JNCC Report No 406.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Shoji, A., Aris-Brosou, S., Fayet, A., Padget, O., Perrins, C. & Guilford, T. 2015. Dual foraging and pair coordination during chick provisioning by Manx shearwaters: empirical

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evidence supported by a simple model. Journal of Experimental Biology 218, 2116-2123; doi: 10.1242/jeb.120626

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M. L., Camphuysen, C. J., Cooper, J., Garthe, S., Montevecchi, W. A., and Blaber, S. J. M. 2000. The impacts of fishing on marine birds. – ICES Journal of Marine Science, 57, 531–547.

Thompson, K.R., & Furness, R.W. 1991. The influence of rainfall and nest-site quality on the population-dynamics of the Manx Shearwater Puffinus puffinus on Rhum. Journal of Zoology, 225, 427–437.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

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Northern fulmar (breeding)

1. Introduction

Northern fulmar is a regularly occurring migratory species. Northern fulmar (breeding) is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for northern fulmar (breeding)

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2. Species account

Table 1 Summary of status of northern fulmar (breeding).

Species’ status Score Notes

GB marine Widespread The widespread distribution of northern fulmar (breeding) in the GB marine environment (JNCC range distribution score 95.0%1) reflects their ability to forage over distances of several hundred kilometres from their

breeding colonies (Thaxter at al, 2012). The highest densities modelled from boat-based and aerial survey data across UK waters were along the shelf break to the north-west of Scotland, around Shetland where there is documented association with fishing activity (Kober et al, 2010) and in the North Sea off northeast England (Bradbury et al, 2017). Significance of High The observed distribution of northern fulmar (breeding) at sea reflects their predominantly northern Scotland’s seas distribution with over 90% of breeding pairs in Scotland and over 50% in the Northern Isles (Mitchell in GB context et al, 2004). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 500,000 pairs, equivalent to 12.2 – 18.5% of the biogeographic population population (glacialis Atlantic) estimated at 2,700,000 - 4,100,000 pairs (Mitchell et al, 2004).

Northern fulmar breed throughout the north Atlantic and north Pacific, ranging from Japan and the United Kingdom in the south to the high Arctic in the north (BirdLife International, 2018). Birds of the nominate (Atlantic) race breed in Eastern Canada, Norway, Iceland, Greenland, Faroes, Britain and Ireland and Western Russia (Mitchell et al, 2004). European Endangered The global conservation status for northern fulmar is Least Concern, however the European population conservation status is Endangered (BirdLife International, 2017& 2018). The conservation statuses conservation differ because although the northern fulmar population is large and distribution is widespread on a status global scale, the European population of northern fulmar has experienced steep declines (magnitude 39%) (BirdLife International, 2017). Species’ status summary and Breeding northern fulmar in GB are of Medium importance to the biogeographic population of this assessment of level of regularly occurring migratory species and the European population status is considered Endangered. representation in Scottish Northern fulmar (breeding) have a widespread distribution at sea, with the highest densities to the

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SPA network. north and northwest of Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of northern fulmar (breeding) in Europe is Medium.

This assessment indicates there is an expectation of northern fulmar (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of northern fulmar (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have high or threats and medium impacts on relevant populations of northern fulmar (breeding) (Furness, 2016). In particular northern fulmar pressures prey extensively on fisheries waste (Phillips et al, 1999) and may be affected by changes to fisheries management aimed at reducing levels of fisheries discards (Bicknell et al, 2013). They are also one of the main seabird species taken as accidental bycatch in long-line fisheries in the northern hemisphere (Tasker et al, 2000; Dunn & Steel, 2001; ICES, 2013) and are identified as among the most potentially sensitive species to bycatch in surface gears in UK waters, but there is no empirical evidence of bycatch rates or impacts (Bradbury et al, 2017). Examination of corpses indicates high levels of plastic ingestion, but there is currently a lack of published information on the population level impacts (Franeker et al, 2011; Provencher et al, 2014).

Reductions in sandeel abundance and changes to plankton communities, probably caused by increases in sea surface temperature, are also likely to be responsible for recent fulmar declines2 and the species is identified as sensitive to climate change (Thompson & Ollason, 2001) with breeding populations likely to suffer moderate or high magnitude declines in response to climate change over the next 40 years under a medium emissions scenario (Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Northern fulmar (breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by site-based protection.

2 http://jncc.defra.gov.uk/page-2868

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3. Contribution to Scottish SPA network

This section considers the occurrence of northern fulmar (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Northern fulmar (breeding) are being considered for inclusion at two marine proposed SPAs and are represented in 24 existing colony SPAs, all of which have marine extensions for fulmar maintenance behaviours.

Table 3 Summary of occurrence of northern fulmar (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Seas off Foula Supports a Northern fulmar (breeding) Provides only example Birds foraging in the Seas off Foula are breeding seabird are represented within 2 of this species on the within mean foraging range (47.5km, assemblage, marine proposed SPAs east coast of Scotland. Thaxter et al, 2012) of the breeding including 8,379 and in 24 existing colony colonies at Foula SPA, Sumburgh Head

northern fulmar3. SPAs, all of which have SPA, Noss SPA and Fair isle SPA. marine extensions for Linkages to many more existing colony

fulmar maintenance SPAs in Scotland are probable as behaviours. breeding northern fulmar have a mean maximum foraging range of 400km

(Thaxter et al, 2012); in the Northern Isles and east coast only the Forth Islands SPA colony is outwith this range from the pSPA.

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Proposed SPAs Representation Replication Geographic range Linkages

Seas off St Kilda Supports a Provides only example Birds foraging in the Seas off St Kilda are breeding seabird of this species on the within mean foraging range (47.5km, assemblage west coast of Scotland. Thaxter et al, 2012) of the breeding including 3,310 colonies at St Kilda SPA and Flannan

northern fulmar3. Isles SPA. Linkages to many more existing colony SPAs in Scotland are probable as breeding northern fulmar have a mean maximum foraging range of 400km (Thaxter et al, 2012); all breeding colony SPAs in the Hebrides and west coast are within this distance of the pSPA.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of northern fulmar (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes two marine pSPAs for northern fulmar (breeding) holding an average of 11,689 birds. One of these pSPAs is within OSPAR region II and the other mainly in OSPAR region III, with a small part of the site in OSPAR Region V. Both sites are within the extensive area to the northwest of Scotland and around Shetland identified as holding the highest summer densities of fulmar in Scotland’s seas (Bradbury et al, 2017) and are within foraging range of 23 (of 24) existing colony SPAs.

The number and distribution of marine proposed sites for northern fulmar (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the species assessment (Table 1).

There is evidence that northern fulmar (breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. However, the drivers for many of these threats and pressures require management at an ecosystem or broader scale. Site-based protection of areas used regularly by large aggregations of northern fulmar (breeding), in conjunction with wider seas measures, may enhance resilience to such threats and pressures. The identification of further marine protected areas for such a wide-ranging and dispersed species is challenging (Kober et al, 2010).

There are functional linkages between the proposed SPAs and two existing colony SPAs. Inclusion of the marine pSPA in the network provides added conservation value by safeguarding marine habitats supporting prey species used by northern fulmar (breeding) from these existing colony SPAs.

5. Conclusion

The number and distribution of marine proposed SPAs for northern fulmar (breeding) is fully justified both in terms of meeting the UK SPA Selection guidelines and the relative value of protected areas in Scotland’s marine environment to the conservation of northern fulmar (breeding) in Europe.

The case for inclusion of northern fulmar (breeding) in the Seas off Foula pSPA and Seas off St Kilda pSPA is further supported because of the functional link with existing colony SPAs.

No further SPA provision is considered necessary for northern fulmar (breeding) however, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing northern fulmar (breeding) populations at the wider seas/ecosystem level.

6. References

A.E.W.A. Report on the conservation status of migratory waterbirds in the agreement area. Agreement on the conservation of African-Eurasian migratory waterbirds. 2012.

Bicknell, A.W.J., Oro, D., Camphuysen, K. & Votier, S.C. 2013. Potential consequences of discard reform for seabird communities. Journal of Applied Ecology, 50, 649–658.

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BirdLife International, 2018. Species factsheet, Fulmarus glacialis. ed http://www.birdlife.org

Dunn, E.K. & Steel, C. 2001. The impact of long-line fishing on seabirds in the north-east Atlantic: recommendations for reduced mortality. RSPB/JNCC, Sandy.

Franeker, J.A., Blaize, C., Danielsen, J., Fairclough, K., Gollan, J., Guse, N., Hansen, P.L., Heubeck, M., Jensen, J.K., Le Guillon, G., Olsen, B., Olsen, K.O., Pedersen, J., Stienen, E.W.M. & Turner, D.M. 2011. Monitoring plastic ingestion by the northern fulmar Fulmarus glacialis in the North Sea. Environmental Pollution, 159, 2609-2615.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

JNCC, 2015. Seabird populations in the identification of marine SPAs. Joint Nature Conservation Committee, Peterborough.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Phillips, R.A., Petersen, M.K., Lilliendahl, K., Solmundsson, J., Hamer, K., Camphuysen, C.J. & Zonfrillo, B. 1999. Diet of the northern fulmar Fulmarus glacialis: reliance on commercial fisheries? Marine Biology, 135, 159-170.

Provencher, J.F., Bond, A.L., Hedd, A., Montevecchi, W.A., Bin Muzaffar, S., Courchesne, S.J., Gilchrist, H.G., Jamieson, S.E., Merkel, F.R., Falk, K., Durinck, J. & Mallory, M.L. 2014. Prevalence of marine debris in marine birds from the North Atlantic. Marine Pollution Bulletin, 84, 411-417.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature

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Tasker, M. L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A. & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531–5

Thompson, P.M. & Ollason, J.C. 2001. Lagged effects of ocean climate change on fulmar population dynamics. Nature, 413, 417-420

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Northern fulmar (non-breeding)

1. Introduction

Northern fulmar is a regularly occurring migratory species. Northern fulmar (non-breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for northern fulmar (non-breeding)

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2. Species account

Table 1 Summary of status of northern fulmar (non-breeding).

Species’ status Score Notes

GB marine Widespread Very widespread distribution in the GB marine environment (JNCC range score 100%). The highest distribution densities modelled from boat-based and aerial survey data across UK waters were in the seas 100- 200km to the north of Scotland along the shelf-break, including to the north of the Western Isles, and around Orkney and Shetland (Bradbury et al, 2017). Low densities occur in English waters (Furness, 2015). Significance of High Tasker (2007) suggests that approximately 1,000,000 northern fulmar winter in Scottish waters, Scotland’s seas representing approximately 89% of the estimated number of birds overwintering in the UK (1,125,103 in GB context individuals; Furness, 2015). GB contribution Medium The best available estimate of the UK1 wintering population for this regularly occurring migratory to biogeographic species is 1,125,103 birds (Furness, 2015), which is approximately 14% of the very large population biogeographic population (with connectivity to UK waters) estimated to be 8,055,000 birds (Furness, 2015). There is moderate (UK wintering population) to high (biogeographic population) uncertainty around these figures, which could range from greater than 50% less to 80% more (Furness, 2015).

Northern fulmar have an extremely large circumpolar range and breed throughout the north Atlantic and north Pacific. They range from the UK, in the southern part of their range, to the high Arctic in the north (BirdLife International 2018). Following breeding, birds disperse to moult but can return to occupy nest sites two months later, although attendance can be sporadic (Furness, 2015). Fulmars wintering in UK waters are thought to predominantly derive from British colonies (driven by colony attendance during winter) but also populations from the Faroe Islands, Iceland and Norway (Furness, 2015). European Endangered The global conservation status for northern fulmar is Least Concern, however the European population conservation status is Endangered (BirdLife International, 2017& 2018). conservation status

1 Furness (2015) provides UK reference populations rather than at a GB scale.

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The conservation statuses differ because although the northern fulmar population is large and distribution is widespread on a global scale, the European population has experienced steep declines (magnitude 39%) (BirdLife International, 2017). Species’ status summary and The GB northern fulmar (non-breeding) population is of Medium importance to the very large assessment of level of biogeographic population of this regularly occurring migratory species. The Scottish wintering representation in Scottish population is of High importance to the widespread GB population. This species’ European population SPA network. status is considered Endangered and therefore, measures to improve conservation status are considered to be of high importance. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of northern fulmar (non-breeding) is Medium.

This assessment indicates there is an expectation of northern fulmar (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of northern fulmar (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of northern fulmar (non-breeding) (Furness, 2016), namely accidental bycatch in fishing nets pressures (Bradbury et al, 2017) and on long-lines (Dunn & Steel, 2001; ICES, 2013). Lower level population impacts include oil spills (Mendel et al, 2008), organochlorine pollution (Knudsen et al, 2007), entanglement in fragments of fishing net and other plastic waste (Mendel et al, 2008), and plastic ingestion (Franeker et al, 2011; Provencher et al, 2014). There is currently a lack of published information on the population level impacts of the widespread issue of plastic ingestion known at an individual level in this species (e.g. impacts on productivity and adult survival). Northern fulmar (non-breeding) may also be affected by changes to fisheries management aimed at reducing levels of fisheries discards (Bicknell et al, 2013).

Breeding populations of northern fulmar are likely to suffer moderate or high magnitude declines in response to climate change over the next 40 years under a medium emissions scenario (Pearce-Higgins et al, 2011), but there is no specific evidence on the impacts of climate change in the non-breeding season. It is recognised that well- managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

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Northern fulmar (non-breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by site-based protection.

3. Contribution to Scottish SPA network

This section considers the occurrence of northern fulmar (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Northern fulmar (non-breeding) is being considered for inclusion at one marine proposed SPA. There are no existing SPAs for this species in this season in Scotland.

Table 3 Summary of occurrence of northern fulmar (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Seas off Foula Supports a non- Northern fulmar (non-breeding) Provides the only Northern fulmar disperse widely to breeding seabird is represented within 2 example of this moult and winter. However, birds may assemblage, proposed SPAs. species in Scotland. return to attend breeding sites as little including northern as two months after leaving the fulmar equivalent There are no existing SPAs for colony, although attendance may be to c. 0.5% of the this species in this season in sporadic (Furness, 2015). Therefore, UK1 non-breeding Scotland. there may be linkages with birds population attending breeding colonies within (calculated from Breeding northern fulmar is foraging range (Thaxter et al, 2012) of Furness, 2015). represented in 24 existing the pSPA. This would include 5 SPAs SPAs, all of which have marine in Shetland but given the huge extensions for fulmar distances over which northern fulmar maintenance behaviours. range, linkages with the pSPA could No sites were identified in extend to colonies further afield within OSPAR Region III. the UK.

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4. Summary

This assessment (Table 1) indicates there is an expectation of northern fulmar (non- breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes one marine pSPA for northern fulmar (non- breeding), in OSPAR Region II, and represents c. 0.5% of the UK non-breeding population, the great majority of which is found in Scottish waters. The proposed SPA network does not reflect the full geographic range and variation of northern fulmar (non-breeding) in Scotland. Non-breeding northern fulmar occur in the seas 100-200km to the north of Scotland along the shelf-break, including to the north of the Western Isles in OSPAR Regions III and V, and around Orkney and Shetland (Bradbury et al, 2017).

The proposed number and distribution of proposed sites for northern fulmar (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is below the minimum level of representation indicated by the species assessment (Table 1).

There is evidence that northern fulmar (non-breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment, such that additional representation and replication in the Scottish pSPA network would be appropriate. However, northern fulmar (non-breeding) has a widely dispersed and unpredictable distribution meaning that a significant marine SPA provision is unrealistic. In addition, most of the anthropogenic pressures that northern fulmar (non-breeding) are vulnerable to exist at the wider ecosystem level and are therefore unlikely to be most appropriately managed through site-based protection (e.g. accidental bycatch, plastic ingestion) (Furness, 2016).

The available evidence does not suggest strong linkages between wintering areas and existing protected areas for this species. Northern fulmar disperse widely during the non- breeding season. However, there may be linkages with birds attending colonies within foraging range (Thaxter et al, 2012) of the pSPA during the non-breeding season.

5. Conclusion

The number and distribution of marine proposed SPAs for northern fulmar (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of northern fulmar (non-breeding) in Europe.

No further SPA provision is considered necessary for northern fulmar (non-breeding). However, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing northern fulmar (non-breeding) populations at the wider seas/ecosystem level.

6. References

Bicknell, A.W.J., Oro, D., Camphuysen, K. & Votier, S.C. 2013. Potential consequences of discard reform for seabird communities. Journal of Applied Ecology, 50, 649–658.

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BirdLife International, 2018. Species factsheet, Fulmarus glacialis. http://www.birdlife.org

Dunn, E.K. & Steel, C. 2001. The impact of long-line fishing on seabirds in the north-east Atlantic: recommendations for reduced mortality. RSPB/JNCC, Sandy.

ICES 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Knudsen, l.B., Borga, K., Jorgensen, E.H., van Barel, B., Schlabach, M., Verreault, J. & Gabrielsen, G.W. 2007. Halogenated organic contaminants and mercury in Northern fulmars (Fulmarus glacialis): levels, relationships to dietary descriptors and blood to liver comparison. Environmental Pollution, 146, 25-33.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M. 2007. Northern Fulmar. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 363 – 367. Scottish Ornithologists’ Club, Aberlady.

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Northern gannet (breeding)

1. Introduction

Northern gannet is a regularly occurring migratory species. Northern gannet is being considered for inclusion within two marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for northern gannet (breeding)

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2. Species account

Table 1 Summary of status of northern gannet (breeding)

Species’ status Score Notes

GB marine Widespread Northern gannet are large birds capable of foraging over distances of hundreds of kilometres (Thaxter distribution et al, 2012). Satellite tracking has shown that birds from different colonies forage in largely mutually

exclusive areas and that colony-specific home ranges are determined by density-dependent competition (Wakefield et al, 2013). These characteristics are reflected in their widespread marine distribution (JNCC range score 99.4%1) with highest densities within foraging range of the largest breeding colonies (Bradbury et al, 2017). Significance of High Northern gannet breed at 20 colonies in GB2 , of which 16, holding 80.7% of the GB population are Scotland’s seas in Scotland (Murray et al, 2015). These include by far the largest colonies, at Bass Rock and St in GB context Kilda, which together hold 55% of the Scottish population and 45% of the GB population. GB contribution High The most recent (2009-2014) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 301,744 pairs, equivalent to 72.3% of the biogeographic population (Northeast population Atlantic) estimated at 417,290 pairs (Murray et al, 2015). The Scottish population represents 58.4% of the biogeographic.

Northern gannet are found on both sides of the Atlantic Ocean with breeding sites in northern France, GB, Ireland, Iceland, Norway, Faroe Islands and Quebec (Canada) (BirdLife International, 2018). The majority (79%) of the population is in the northeast Atlantic (Murray et al, 2015). European Least The global and European conservation status for northern gannet is Least Concern (BirdLife population Concern International, 2017 & 2018). conservation status

Species’ status summary and Breeding northern gannet in GB (and Scotland) are of High importance to the biogeographic assessment of level of population of this regularly occurring migratory species and the European population status is representation in Scottish considered Least Concern. Northern gannet (breeding) have a widespread distribution at sea, with the

SPA network. highest densities in Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of northern gannet (breeding) in Europe is Medium.

This assessment indicates there is an expectation of northern gannet (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of northern gannet (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have high or threats and medium impacts on relevant populations of northern gannet (breeding) (Furness, 2016). These include mortality as a pressures result of collision with offshore wind farm turbines (Furness et al, 2013; ICES, 2015). Accidental bycatch of northern gannets in gill nets has been reported for a number of fisheries in the North Atlantic (Žydelis et al, 2013). Gannets are also susceptible to capture in trawls and purse seines (ICES, 2013) and on long-lines (Wernham et al, 2002) and to entanglement in discarded fishing net and other plastic waste (Rodriguez et al, 2013). Northern gannet are identified as among the most potentially vulnerable species to bycatch in both surface and pelagic gears in UK waters given both their susceptibility to entanglement and their distribution at sea in relation to relevant fishing activity (Bradbury et al, 2017), but there is no systematic data from which to assess bycatch rates or impacts (ibid). The potential impacts on breeding northern gannet populations of recent changes to discarding practices in commercial fisheries are uncertain (Bicknell et al, 2013)

Northern gannets can travel great distances from their nest site to forage and are able to exploit a wide range of prey. Hence, they may have greater potential than some other seabird species to adapt to climate change, although there is no clear consensus on this (Huntley et al, 2007; Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Northern gannet (breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures. Replication within OSPAR regions is recommended.

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3. Contribution to Scottish SPA network

This section considers the occurrence of northern gannet (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Northern gannet (breeding) are being considered for inclusion at two marine proposed SPAs and are represented in 8 existing colony SPAs, all of which have marine extensions for gannet maintenance behaviours.

Table 3 Summary of occurrence of northern gannet (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports a breeding seabird Northern gannet Provides only Birds foraging in the Outer Forth and St assemblage, including 10,945 (breeding) is represented example for this Firth of Forth and St Andrews Andrews Bay northern gannet3. within two proposed species on the east Bay Complex are thought to Complex SPAs and 8 existing coast of Scotland. derive mainly from the Bass

SPAs, all of which have Rock, within the Forth Islands

marine extensions for SPA (Wakefield et al, 2013). gannet maintenance Seas off St Kilda Supports a breeding seabird Provides only Birds foraging in the Seas off behaviours. assemblage, including 50,332 example for this St Kilda are thought to derive northern gannet3. species on the west mainly from the St Kilda SPA coast of Scotland. (Wakefield et al, 2013).

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4. Summary

The species assessment (Table 1) indicates there is an expectation of northern gannet (breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The proposed Scottish SPA network includes two marine pSPAs for northern gannet (breeding) that together hold an average of 61,277 birds3. The Outer Firth of Forth and St Andrews Bay Complex pSPA is within OSPAR region II and is used by birds from the largest GB colony at Bass Rock. The Seas off St Kilda pSPA is mainly in OSPAR region III, with a small part of the site in OSPAR Region V, and is used by birds from the second largest GB colony at St Kilda. This distribution of sites reflects the most important areas for gannets in Scottish waters in the breeding season (Bradbury et al, 2017).

The number and distribution of marine proposed sites for northern gannet (breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the level of representation indicated by the species assessment (Table 1).

Replication in OSPAR regions overlapping the Scottish distribution of northern gannet (breeding) would be desirable because there is evidence that northern gannet (breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Some of these threats and pressures require management at an ecosystem or broader scale but site-based protection of areas used regularly by large aggregations complements wider measures and is considered an appropriate conservation measure to enhance resilience of northern gannet (breeding).

Potentially suitable additional sites are, however, currently not known and no other hotspots meeting the population thresholds/regularity requirements for SPA selection were identified for northern gannet (breeding) by the European Seabirds at Sea (ESAS) analysis.

There are functional linkages between the marine pSPAs and existing colony SPAs; the proposed sites encompass core modelled foraging areas for breeding northern gannet from the St Kilda SPA and Forth Islands SPA.

5. Conclusion

The number and distribution of marine proposed SPAs for northern gannet (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of northern gannet (breeding) in Europe.

The case for inclusion of breeding northern gannet in the Outer Firth of Forth and St Andrews Bay Complex pSPA and Seas off St Kilda pSPA is further supported because they are functionally linked to existing colony SPAs.

Further SPA provision or additional site-based and/or alternative conservation measures are recommended for northern gannet (breeding). Substantial further work (including survey and/or additional analyses) would be required to identify potentially suitable sites.

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6. References

Bicknell, A.W.J., Oro, D., Camphuysen, K. & Votier, S.C. 2013. Potential consequences of discard reform for seabird communities. Journal of Applied Ecology, 50, 649–658. doi:10.1111/1365-2664.12072

BirdLife International, 2018. Species factsheet, Morus bassanus. http://www.birdlife.org

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66

Huntley, B., Green, R.E., Collingham, Y.C. & Willis, S.G. 2007. A climatic atlas of European breeding birds. Durham University, RSPB and Lynx Edicions, Barcelona. 521 pp.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

ICES 2015. Report of the Joint OSPAR/HELCOM/ICES Working Group on Seabirds (JWGBIRD). ICES CM2015/ACOM: 28.

Murray, S., Harris, M.P. & Wanless, S.2015. The status of the Gannet in Scotland in 2013– 14, Scottish Birds, 35, (1) 3-18.

Rodriguez, B., Becares, J., Rodriguez, A. & Arcos, J.M. 2013. Incidence of entanglement with marine debris by northern gannets (Morus bassanus) in the non-breeding grounds. Marine Pollution Bulletin, 75, 259-263.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wakefield, E.D., Bodey, T.W., Bearhop, S., Blackburn, J., Colhoun, K., Davies, R., Dwyer, R.G., Green, J.A., Grémillet, D., Hamer, K.C., Jackson, A.L., Jessopp, M.J., Kane, A.,

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Langston, R.H.W., Lescroël, A., Murray, S., Le Nuz, M., Patrick, S.C., Péron, C., Soanes, L.M., Wanless, S. & Votier, S.C. 2013. Space partitioning without territoriality in gannets. Science, 341, (6141), 68-70. DOI: 10.1126/science.1236077

Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds.) 2002. Migration Atlas: movements of birds of Britain and Ireland. Poyser, London

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

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Northern gannet (non-breeding)

1. Introduction

Northern gannet is a regularly occurring migratory species. No pSPAs have been identified for northern gannet (non-breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of northern gannet (non-breeding).

Species’ status Score Notes

GB marine Widespread Very widespread distribution in the GB marine environment (JNCC range score 95.7%1). The highest distribution densities modelled from boat-based and aerial survey data across UK waters were around St Kilda, the south-east coast of Scotland and north-east England, Dogger Bank, and south-west England. Generally high densities were modelled around west and north Scotland (including Orkney and Shetland), the Firth of Forth extending east into the North Sea, the east and south coasts of England, and into the Celtic Sea south-west of Wales (Bradbury et al, 2017). Significance of Low Zonfrillo (2007) suggests a few thousand northern gannet winter in Scottish waters, which is a small Scotland’s seas proportion of the number of birds estimated to overwinter or move through UK waters during the non- in GB context breeding season (910,273-1,002,252 individuals; Furness, 2015). GB contribution High The best available estimate of the UK2 wintering population for this regularly occurring migratory to biogeographic species is 910,273-1,002,252 (Furness, 2015), which is approximately 77-85% of the population biogeographic population (with connectivity to UK waters) estimated to be 1,180,000 birds (Furness, 2015). There is low uncertainty around these figures (Furness, 2015).

Northern gannet has a very large range, but its core breeding range falls within the UK, with Scotland holding approximately 50% of the world population of breeding northern gannet. Outside the UK there are colonies in Norway, Russia, Faroe Islands, Iceland, Canada, Germany and France (Zonfrillo, 2007; BirdLife International, 2017). Following breeding, most birds move slowly south to winter in the

1 Derived from the distribution models in WWT Consulting (2016) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Furness (2015) provides UK reference populations rather than at a GB scale.

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Bay of Biscay, Celtic Sea, Mediterranean and off the coast of West Africa. Some birds overwinter in the North Sea or the English Channel (Furness, 2015). European Low The global and European conservation status for northern gannet is Least Concern (BirdLife population International, 2017 & 2018). conservation status Species’ status summary and The GB northern gannet (non-breeding) population is of high importance to the biogeographic assessment of level of population, with the Scottish wintering population of this regularly occurring migratory species being of representation in Scottish very low importance to the GB wintering population. This species’ European population status is SPA network. considered Least Concern and therefore, measures to improve their conservation status are considered to be of low importance. Accordingly, the overall assessment of the relative importance of Scotland to northern gannet (non-breeding) in Europe is Very Low.

This assessment indicates there is no expectation of northern gannet (non-breeding) being represented in the Scottish SPA network.

Table 2 Vulnerability of northern gannet (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have high and medium impacts threats and on relevant populations of northern gannet (non-breeding) (Furness, 2016). These include mortality as a result of pressures collision with offshore wind farm turbines (Furness et al, 2013; ICES, 2015), and accidental bycatch in fishing nets (Bradbury et al, 2017) and on long-lines (Mendel et al, 2008). Lower level potential threats or pressures include oil spills (Camphuysen, 2001) and entanglement in discarded fishing net and other plastic waste (Rodriguez et al, 2013). Other potential threats include prey depletion as a result of fisheries activities (BirdLife International, 2018). The potential impacts of climate change on northern gannet in the UK are unclear, although one model suggests northern gannet populations could be negatively affected by climate change (Russell et al, 2015). Until more evidence is available well-managed protected sites could be important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Northern gannet (non-breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by site-based protection.

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3. Summary

The species assessment indicates there is no expectation of northern gannet (non-breeding) being represented in the Scottish SPA network.

No sites have been identified for northern gannet (non-breeding) in the Scottish pSPA network which is consistent with the species’ status assessment (Table 1).

Northern gannet (non-breeding) has a widely dispersed and unpredictable distribution meaning that a significant marine SPA provision is unrealistic.

4. Conclusion

The species assessment confirms that SPA provision is not considered an appropriate conservation measure for this northern gannet (non-breeding) due to the widely dispersed and unpredictable nature of their distribution.

5. References

BirdLife International, 2018. Species factsheet, Morus bassanus. http://www.birdlife.org

Camphuysen, C.J. 2001. Northern gannets Morus bassanus found dead in the Netherlands, 1970-2000. Atlantic Seabirds, 3, 15-30.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

ICES 2015. Report of the Joint OSPAR/HELCOM/ICES Working Group on Seabirds (JWGBIRD). ICES CM2015/ACOM:28.

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SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Zonfrillo, B. 2007. Northern Gannet. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 394 – 398. Scottish Ornithologists’ Club, Aberlady.

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Razorbill (breeding)

1. Introduction

Razorbill is a regularly occurring migratory species. No marine proposed SPAs have been identified for razorbill (breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of razorbill (breeding)

Species’ status Score Notes

GB marine Partially Razorbill (breeding) have a partially restricted distribution in the GB marine environment (JNCC range distribution restricted score 69.8%1). Modelling of boat-based and aerial survey data across UK waters shows consistently high densities in waters extending up to c.50-100km offshore around the east coast of GB from

Yorkshire northwards, around Orkney and along the Scottish north and west coasts (Bradbury et al, 2017). Significance of High The distribution of razorbill at sea in the breeding season reflects that of breeding colonies, with 85.4% Scotland’s seas of GB breeding birds in Scotland and two thirds of the English population in Northumberland and in GB context Humberside (Mitchell et al, 2004). GB contribution Medium The most recent (1998-2002) estimate of the GB breeding population of this regularly occurring to biogeographic migratory species is 110,000 pairs2, equivalent to 20.8% of the biogeographic population (islandica population NW Europe) estimated at 530,000 pairs (Mitchell et al, 2004).

Razorbills breed around the north Atlantic in eastern North America, Greenland, the White Sea, Norway, Denmark, Iceland, Faroe Islands, GB & Ireland, Germany and France (BirdLife International, 2017; Furness, 2015). Those in GB are from the islandica race for which Iceland is the most important breeding ground, the largest populations of the nominate torda race are in eastern Canada and Norway (ibid).

1 Derived from the distribution models in WWT Consulting (2016) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Estimated by applying a standard correction factor of x0.67 to counts of individuals attending colonies (Mitchell et al, 2004)

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European Medium The global and European conservation status for razorbill is Near Threatened (BirdLife International, population 2017 & 2018). conservation status Species’ status summary and Razorbill (breeding) in GB are of Medium importance to the biogeographic population of this regularly assessment of level of occurring migratory species and the European population status is considered Near Threatened. representation in Scottish Razorbill (breeding) have a Partially Restricted distribution at sea, with the highest densities in SPA network. Scotland. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of razorbill (breeding) in Europe is High.

This assessment indicates there is an expectation of razorbill (breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of razorbill (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have threats and medium impacts on relevant populations of razorbill (breeding) (Furness, 2016). In particular, razorbill are pressures susceptible to fatal bycatch in set (gill) net fisheries (see summaries in Tasker et al, 2000; Žydelis et al, 2013; and, Bradbury et al, 2017), although the large numbers drowned in former coastal salmon fisheries off NE Scotland in the 1990s (Murray et al, 1994) were not thought to have been significant at a wider population level (Tasker et al, 2000; Bradbury et al, 2017). Razorbill are identified as among the most potentially vulnerable species to bycatch in surface gears in UK waters given both their susceptibility to entanglement and their distribution at sea in relation to relevant fishing activity (Bradbury et al, 2017), but there is no systematic data from which to assess bycatch rates or impacts (ibid).

Razorbill have been identified as potentially at relatively high risk of collision with tidal turbines (Furness et al, 2012; McCluskie et al, 2012) but empirical data are lacking. They are also susceptible to large scale mortality in major oil spills (Mendel et al, 2008) and show sensitivity to visual disturbance associated with shipping (Mendel et al, 2008).

Breeding razorbill feed on small shoaling pelagic fish, including sprat, herring and sandeels (Mendel et al, 2008) and are vulnerable to reductions in availability of such prey. Changes in sandeel productivity and energy content

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(Wanless et al, 2005), potentially linked to climate change, have been associated with declines in razorbill breeding success3 and breeding populations of razorbill are predicted to suffer moderate declines in response to climate change over the next 40 years under a medium emissions scenario (Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Razorbill (breeding) populations are vulnerable to medium impacts from a number of different threats and pressures. Replication within OSPAR regions is recommended.

3 http://jncc.defra.gov.uk/page-2899

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3. Summary

The species assessment (Table 1) indicates there is an expectation of razorbill (breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

No marine proposed SPAs have been identified for razorbill (breeding) in the Scottish pSPA network. Razorbill (breeding) is represented in 30 existing colony SPAs, all of which have marine extensions for razorbill maintenance behaviours.

Representation in the Scottish pSPA network is desirable because common razorbill (breeding) are vulnerable to a range of anthropogenic pressures, some of which (e.g. net entanglement and collision with tidal turbines) could be managed through provision of site- based protection encompassing supporting habitats (e.g. foraging locations).

No marine pSPAs for razorbill (breeding) have been included in the Scottish marine network because no regular hotspots with sufficient densities (numbers) of razorbill (breeding) were identified through the analyses of European Seabirds at Sea (ESAS) database undertaken to support site selection (Kober et al, 2010). This may in part reflect the much smaller size (c.93,000 pairs) of Scottish breeding razorbill populations as compared with common guillemot (c.780,000 pairs) and puffin (c. 490,000 pairs) (Mitchell et al, 2004).

Models of the distribution of razorbills at sea during the breeding season suggest a more even distribution than other auk species (see Figures 124, 126 and 133 in Bradbury et al, 2017) although previous analyses (Stone et al, 1995) have indicated relatively high densities during the incubation and chick-rearing periods over relatively large areas in the Moray Firth, the Minch and off NW Scotland. Such a large scale pattern might be anticipated given colonies at East Caithness Cliffs, Cape Wrath, Handa, Mingulay and Berneray, and Shiants, but is not necessarily indicative of the presence smaller scale consistent aggregations.

Breeding razorbill feed their young on small fish including sandeels and Clupeidae (Harris and Wanless, 1989; Wakefield et al, 2017). Thaxter et al (2012) reported a mean foraging range of 23.7 ± 7.5km while recent tracking studies indicate that breeding razorbill typically forage within 13 km from their colonies, but that birds from colonies in the Northern Isles, where breeding success has apparently been low in recent years3, travel much further, typically around 60km (Kuepfer, 2012; Wakefield et al, 2017).

4. Conclusion

SPA provision in the Scottish marine SPA network or additional site-based and/or alternative conservation measures are recommended for razorbill (breeding). There may be potential for future identification of consistently important foraging areas at sea in vicinity of relatively large and stable razorbill colonies informed by tracking and/or higher resolution surveys of distributions at sea.

5. References

BirdLife International, 2018. Species factsheet, Uria aalge. http://www.birdlife.org

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Harris, M. P. & Wanless, S. 1989. The breeding biology of Razorbills Alca torda on the Isle of May, Bird Study, 36, 2, 105-114, DOI: 10.1080/00063658909477012

Kuepfer, A. 2012. Foraging patterns and home-ranges of breeding razorbills (Alca torda) from two colonies in North Wales, UK, as revealed by GPS-tracking in the seasons of 2011 and 2012. MSc thesis; University of North Wales.

McCluskie, A.E., Langston, R.H.W. & Wilkinson, N.I. 2013. Birds and Wave & Tidal Stream Energy: An Ecological Review. RSPB Research Report No. 42. Sandy: RSPB.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Tasker, M.L., Camphuysen, C.J., Cooper, J., Garthe, S., Montevecchi, W.A., & Blaber, S.J.M. 2000. The impacts of fishing on marine birds. ICES Journal of Marine Science, 57, 531–5.

Wakefield, E.D., Owen, E., Baer, J., Carroll, M.J., Daunt, F., Dodd, S.G., Green, J. A., Guilford, T., Mavor, R.A., Miller, P. I., Newell, M.A., Newton, S.F., Robertson, G. S., Shoji, A., Soanes, L.M., Votier, S.C., Wanless, S. & Bolton, M. 2017. Breeding density, fine-scale tracking, and large-scale modelling reveal the regional distribution of four seabird species. Ecological Applications, 27, 2074–2091

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Wanless, S., Harris, M.P., Redman, P. & Speakman, J. 2005. Low fish quality as a probable cause of a major seabird breeding failure in the North Sea. Marine Ecology Progress Series, 294, 1-8.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-8

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Razorbill (non-breeding)

1. Introduction

Razorbill is a regularly occurring migratory species. Razorbill (non-breeding) is being considered for inclusion within one marine proposed SPA. This is shown in Figure 1.

Figure 1 Map showing the marine proposed SPA for razorbill (non-breeding)

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2. Species account

Table 1 Summary of status of razorbill (non-breeding)

Species’ status Score Notes

GB marine Restricted Restricted distribution in the GB marine environment (JNCC range score 53.7%1). The highest distribution densities modelled from boat-based and aerial survey data across UK waters were around the

western, eastern and north-western (Sutherland) coasts of Scotland, with smaller hotspots over Dogger Bank and off southern Ireland. Lesser densities were modelled around Orkney, north-east England and the south-west coast of England and Wales (Bradbury et al, 2017). Significance of Low Lauder (2007) suggests that 50,000-250,000 razorbills winter in Scottish waters representing 9-45% of Scotland’s seas the estimated number of birds overwintering in the UK (560,044 individuals; Furness, 2015). Furness in GB context (2015) suggests greater numbers winter in English waters, although the converse is indicated in modelled density maps (Bradbury et al, 2017). GB contribution High The best available estimate of the UK2 wintering population of this regularly occurring migratory to biogeographic species is 560,044 birds (Furness, 2015), which is approximately 30% of the biogeographic population population (with connectivity to UK waters) estimated to be 1,707,000 birds (Furness, 2015). There is high uncertainty around these figures which could range from greater than 50% less to 80% more (Furness, 2015).

Razorbills breed around the north Atlantic in eastern North America, Greenland, the White Sea, Norway, Denmark, Iceland, Faroe Islands, GB, Germany and France (BirdLife International, 2017; Furness, 2015). Breeding populations with connectivity to UK waters during winter are located in Iceland, Faroe Islands, Norway, Russia, Sweden, Finland, Denmark and Ireland (Furness, 2015). Razorbills wintering in UK waters are thought to derive mainly from breeding populations in the UK, Iceland, Faroe Islands and Norway (Furness, 2015). Scottish breeding razorbills are thought to move east to southwest Norway and Denmark, or the southern North Sea to winter (Furness, 2015).

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European Near The global and European conservation status for razorbill is Near Threatened (BirdLife International, population Threatened 2017& 2018). conservation status Species’ status summary and The GB razorbill (non-breeding) population is of High importance to the biogeographic population, with assessment of level of the Scottish wintering population of this regularly occurring migratory species being of Low importance representation in Scottish to the GB population, which has a Restricted distribution. This species’ European population status is SPA network. considered Near Threatened and therefore, measures to improve conservation status are considered to be of medium importance. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to the conservation of razorbill (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of razorbill (non-breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of razorbills (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of razorbills (non-breeding) (Furness, 2016). These include displacement as a result of offshore pressures wind farm developments (Furness et al, 2013), accidental bycatch in fishing nets (Bradbury et al, 2017), depletion of prey resources by fishing activities (Mendel et al, 2008; Heubeck et al, 2011) and oil spills (Mendel et al, 2008). There is potential for individual level impacts on razorbills (non-breeding) through collision with tidal-stream energy generating devices and through displacement caused by vessel activities associated with marine developments; however, potential population level impacts are currently unknown (Furness et al, 2012).

Razorbill (non-breeding) populations are vulnerable to high or medium impacts from a number of different threats and pressures most of which require appropriate management at a broader scale than afforded by site-based protection.

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3. Contribution to Scottish SPA network

This section considers the occurrence of razorbill (non-breeding) within the proposed SPAs and existing SPAs in Scotland. Razorbill (non- breeding) is being considered for inclusion at one marine proposed SPA. There are no existing SPAs for this species in this season in Scotland.

Table 3 Summary of occurrence of razorbill (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports c. 1% of Razorbill (non-breeding) are Provides only Razorbills breeding in Scottish Forth and St the UK non- represented within 1 proposed example of this protected areas are thought to Andrews Bay breeding SPA. species in Scotland. move east during the non-breeding Complex population season to southwest Norway and (calculated from There are no existing SPAs for Denmark, or the southern North Furness, 2015). non-breeding razorbill in Sea (Furness, 2015). Scotland but breeding razorbill is represented in 16 existing However, there may be linkages colony SPAs. with birds attending colonies within foraging range (Thaxter et al, 2012) No sites were identified in of the pSPA during post and pre- OSPAR Region III. breeding (e.g. Forth Islands SPA, St Abb’s Head to Fastcastle SPA and Fowlsheugh SPA).

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4. Summary

The species assessment (Table 1) indicates there is an expectation of razorbill (non- breeding) being represented once or twice in the Scottish SPA network.

The Scottish SPA network includes one marine proposed SPA in OSPAR Region II for razorbill (non-breeding) supporting c. 1% of the UK non-breeding population. The proposed SPA network does not reflect the full geographic range and variation of razorbill (non- breeding) in Scotland. The highest densities in UK waters occur in Scotland, along the east, west and Orkney coastlines (Bradbury et al, 2017). The species occurs in varied environments, including the more sheltered waters of Orkney and the West Coast islands, and in more exposed areas of sea on the Atlantic and North Sea coast.

The number and distribution of proposed sites for razorbill (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is however consistent with the level of representation indicated by the species assessment (Table 1).

Razorbills (non-breeding) are vulnerable to a range of anthropogenic pressures, most of which exist at the wider ecosystem level and are therefore unlikely to be most appropriately managed through site-based protection (e.g. depletion of prey). However, some anthropogenic pressures (e.g. displacement as a result of offshore wind farm developments) could be managed through provision of site-based protection encompassing supporting habitats (e.g. foraging locations) (Furness, 2016). Razorbill (non-breeding) has a widely dispersed and unpredictable distribution meaning that a significant marine SPA provision is unrealistic.

The available evidence does not suggest strong linkages between wintering areas and existing protected areas for this species. Razorbills breeding in Scottish protected areas are thought to move east during the non-breeding season to southwest Norway and Denmark, or the southern North Sea (Furness, 2015). However, there may be linkages with birds attending colonies within foraging range (Thaxter et al, 2012) of the pSPA during post and pre-breeding (e.g. Forth Islands SPA, St Abb’s Head to Fastcastle SPA and Fowlsheugh SPA).

5. Conclusion

The number and distribution of marine proposed SPAs for razorbill (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of razorbill (non-breeding) in Europe.

No further SPA provision is considered necessary for razorbill (non-breeding) however, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing razorbill (non-breeding) populations at the wider seas/ecosystem level.

6. References

BirdLife International, 2018. Species factsheet, Alca torda. http://www.birdlife.org

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Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assesssing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66.

Heubeck, M., Aarvak, T., Isaksen, K., Johnsen, A., Petersen, I.K. & Anker-Nilssen, T. 2011. Mass mortality of adult razorbills Alca torda in the Skagerrak and North Sea area, Autumn 2007. Seabird, 24, 11-32.

Lauder, A. 2007. Razorbill. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 2: 852 – 856. Scottish Ornithologists’ Club, Aberlady.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

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Red-breasted merganser (non-breeding)

1. Introduction

Red-breasted merganser is a regularly occurring migratory species. Red-breasted merganser (non-breeding) is being considered for inclusion within seven marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for red-breasted merganser (non- breeding)

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2. Species account

Table 1 Summary of status of red-breasted merganser (non-breeding)

Species’ status Score Notes

GB marine Widespread Red-breasted merganser (non-breeding) winter predominantly in shallow coastal waters and are distribution widely distributed around GB. They were present in 73.5% of coastal squares surveyed for the 2007- 11 Atlas (Balmer et al, 2014)1 and in an average of 57.1% of coastal core WeBS count sectors counted between 2011 and 20152. Significance of High The largest concentrations are mainly found in Scotland (Austin et al, 2017; Balmer et al, 2014; Scotland’s seas Bradbury et al, 2017) notably in the Northern Isles, western Scotland and east coast Firths. in GB context GB contribution Medium The GB wintering population of this regularly occurring migratory species is 8,400 birds (Musgrove et to biogeographic al, 2013) which is approximately 4.9% of the biogeographic (North-west & Central Europe) population population, estimated at 170,000 birds (Wetlands International, 2015 & 2018).

Red-breasted merganser have a circumpolar breeding range and wider wintering range. The biogeographic population breeds in North & North-west Europe, south to the UK, Iceland and Eastern Greenland. The birds wintering in GB include British breeding birds, the majority of the Icelandic breeding population, and some European birds (Wernham et al, 2002; Wright et al, 2012). European Near The European conservation status for red-breasted merganser is Near Threatened and the global population threatened conservation status is Least Concern (BirdLife International, 2017 a & b). This reflects an apparent conservation decline in Europe but a stable global population (estimated to number c.495,000 - 605,000 birds). status Species’ status summary and Red-breasted merganser (non-breeding) have a Widespread distribution in GB inshore waters, with assessment of level of the largest concentrations mainly in Scotland. GB is of Medium importance to the biogeographic representation in Scottish wintering population and the European population status is considered Near Threatened. Accordingly, SPA network. the overall assessment of the relative value of protected areas in Scotland’s marine environment to the

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conservation of red-breasted merganser (non-breeding) is Medium.

This assessment indicates there is an expectation of red-breasted merganser (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of red-breasted merganser (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is no specifically documented evidence of activities likely to occur in in UK waters generating pressures or threats and threats likely to have either high or medium impacts on relevant populations of red-breasted merganser (non- pressures breeding) (Furness, 2016). This in part reflects the species’ high reproductive potential, widespread and typically coastal distribution and a diet predominantly of small non-commercial fish species.

Red-breasted mergansers exhibit high visual sensitivity to vessel movements (Mendel et al, 2008; Jarrett et al, 2018) and also appear more sensitive than other waterfowl to sudden loud noise (Jarrett et al, 2018). Incidental entanglement in set net fisheries has been documented in the Baltic and Lake Ijsselmeer (Netherlands) (Mendel et al, 2008; Žydelis et al, 2013) but red-breasted merganser populations are not identified as being at significant risk from fisheries bycatch in UK waters (Bradbury et al, 2017).

Recent apparent shifts in wintering range may potentially be linked to climate change (Holt et al, 2011). Well- managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

3. Contribution to Scottish SPA network

This section considers the occurrence of red-breasted merganser (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Red-breasted merganser (non-breeding) is being considered for inclusion at seven marine proposed SPAs and is a feature of five existing estuarine/coastal SPAs, all of which are contiguous with one of the marine pSPAs.

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Table 3 Summary of occurrence of red-breasted merganser (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Outer Firth of Supports a non- Red-breasted merganser Provides an example on Red-breasted merganser (non- Forth and St breeding waterfowl (non-breeding) is the east mainland coast breeding) is a feature of the non- Andrews Bay assemblage, represented within 7 and represents the breeding waterbird assemblage of Complex including red- proposed SPAs and 5 southern extent of the the Firth of Forth SPA and the Firth breasted existing estuarine/coastal range of this species in of Tay and Eden Estuary SPA which merganser SPAs. Scotland. are contiguous with this marine equivalent to c. proposed SPA. 5.1% of the GB Replication of this feature non-breeding in the network is proposed The red-breasted merganser population. in OSPAR Regions II and population in this area will use both III. (intertidal) estuarine and (sub-tidal) marine environments.

Moray Firth Supports c. 1.8% Provides an example on Red-breasted merganser (non- of the GB non- the east mainland coast in breeding) is a feature of the non- breeding the core part of the range breeding waterbird assemblage of population. of this species Scotland. the Inner Moray Firth SPA, Cromarty Firth SPA and the Moray and Nairn Coast SPA which are contiguous with this marine proposed SPA.

The red-breasted merganser population in this area will use both (intertidal) estuarine/coastal and (sub-tidal) marine environments. Scapa Flow Supports c. 6.4% Provides an example in No known linkages of the GB non- the Northern Isles and breeding represents a core part of population. the range of this species in Scotland.

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Proposed SPAs Representation Replication Geographic range Linkages

North Orkney Supports c. 4.1% Provides an example in No known linkages of the GB non- the Northern Isles and breeding represents a core part of population. the range of this species in Scotland. East Mainland Supports c. 2.8% Provides an example in No known linkages Coast, Shetland of the GB non- the Northern Isles and breeding represents the northern population. extent of the range of this species in Scotland. West Coast of Supports c. 2.8% Provides only example in No known linkages the Outer of the GB non- the Outer Hebrides, a core Hebrides breeding part of the range of this population. species in Scotland. Sound of Gigha Supports c. 1.4% Provides only example on No known linkages of the GB non- the west mainland coast breeding and represents the population. southern extent of the range of this species in Scotland.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of red-breasted merganser (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

The Scottish SPA network includes seven marine proposed SPAs for red-breasted merganser (non-breeding) and five existing estuarine/coastal SPAs. The marine proposed SPAs support up to 25.5% of the GB non-breeding population with proposed sites and replication in both OSPAR Regions II and III. The locations of the proposed SPAs reflect the full geographic range and variation of red-breasted merganser (non-breeding) in Scotland’s marine environment from the Northern Isles to the south-west coast and including east coast Firths. The proposed sites also reflect the varied environments in which red-breasted mergansers occur (e.g. from the exposed West Coast of the Outer Hebrides to the more sheltered waters of sites such as Scapa Flow).

The number and distribution of proposed sites for red-breasted merganser (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is higher than indicated by the species assessment (Table 1).

There is no direct evidence that non-breeding red-breasted merganser are vulnerable to anthropogenic threats and pressures, and hence no justification for additional replication within the network to enhance resilience of the species in Scotland. However, added conservation value would be achieved in the marine SPA network by the inclusion of red- breasted merganser (non-breeding) in the Outer Firth of Forth and St Andrews Bay Complex pSPA and Moray Firth pSPA; these pSPAs are contiguous with existing estuarine/coastal SPAs and together these sites encompass the full range of habitats used by red-breasted merganser (non-breeding) within Scotland’s largest Firths.

There is local geographic replication within the Northern Isles in OSPAR Region II with two pSPAs for red-breasted merganser (non-breeding) in Orkney, at North Orkney and Scapa Flow. North Orkney pSPA and Scapa Flow pSPA represent the core part of the range of this species in Scotland together supporting up to 10.5% of the GB population, which is an exceptional concentration for such a widely distributed coastal species. Of the two Orkney sites, Scapa Flow pSPA holds the largest number of red-breasted merganser (non-breeding) in the Scottish pSPA network and North Orkney the third largest.

5. Conclusion

No further SPA provision in Scotland's marine environment is considered necessary for red- breasted merganser (non-breeding) however, a review of the level of representation in the Scottish marine proposed SPA network and in particular, the Northern Isles is required by the Advisory Panel.

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6. References

Balmer, D, Gillings, S., Caffrey, B., Swann, B., Downie, I. & Fuller, R. 2014. Bird Atlas 2007- 11: The Breeding and Wintering Birds of Britain and Ireland. BTO, BirdWatch Ireland, and SOC. BTO Bird Atlas Mapstore https://app.bto.org/mapstore/StoreServlet

BirdLife International, 2017a. European birds of conservation concern: populations, trends and national responsibilities. Staneva, A. & Burfield, I. (comps.). http://www.birdlife.org/europe-and-central-asia/European-birds-of-conservation-concern

BirdLife International, 2017b. Species factsheet: Mergus serrator. http://www.birdlife.org

Holt, C., Austin, G., Calbrade, N., Mellan, M., Mitchell, C., Stroud, D.A., Wotton, S. & Musgrove, A. 2011. Waterbirds in the UK 2009/10. The Wetland Bird Survey. BTO, WWT, RSPB & JNCC, Thetford.

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M. 2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds.) 2002. Migration Atlas: movements of birds of Britain and Ireland. Poyser, London

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

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Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-88

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Red-throated diver (breeding)

1. Introduction

Red-throated diver is an Annex 1 species. Red-throated diver (breeding) is being considered for inclusion within six marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for red-throated diver (breeding)

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2. Species account

Table 1 Summary of status of red-throated diver (breeding)

Species’ status Score Notes

GB marine Highly The distribution of breeding red-throated divers in GB is confined to Scotland, principally Shetland, distribution restricted Orkney, the Inner and Outer Hebrides and the northern mainland (Dillon et al, 2009). Red-throated divers breed on remote freshwater lochs but feed primarily in coastal waters, typically within a range of 10km from their breeding site (Black et al, 2015). Significance of High The entire GB breeding population is found in northern and western Scotland. Scotland’s seas in GB context GB contribution Medium The GB breeding population of this Annex 1 species is 1,255 pairs (Dillon et al, 2009; rounded to to biogeographic 1,300 in Musgrove et al, 2013). This equates to 16.2% of the total breeding population in the UK, population Greenland and Fennoscandia of 7,755 pairs; this “limited biogeographic” region is defined by Furness (2015) as that encompassing the origins of red-throated divers that winter in UK waters and the population estimate is similar to that of 7,160 pairs in Stroud et al (2001) (derived from Hagemeijer et al, 1997). The 3rd SPA review1 cites a biogeographic (Europe) population of 27,000 pairs, derived from BirdLife International (2004), but Furness (2015) questions the veracity of this figure which includes an estimated of 5,000-30,000 pairs for Greenland. If this higher population estimate is used, the proportion in GB is 4.6%; this does not affect the status score (medium). Population Depleted The European population conservation status is Depleted (BirdLife International, 2017). conservation The global conservation status is Least Concern; this reflects the very large size and range of the status global population (BirdLife International, 2018)

1 http://jncc.defra.gov.uk/pdf/UKSPA3_Red-throated%20Diver%20Gavia%20stellata%20(breeding).pdf

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Species’ status summary and The European population status of red-throated diver (breeding) is considered Depleted and therefore, assessment of level of measures to improve its conservation status are considered to be of importance. GB is of Medium representation in Scottish importance to the biogeographic population of this Annex 1 species. Red-throated diver (breeding) SPA network. have a highly restricted distribution in GB waters confined entirely to Scotland, which holds 100% of the GB breeding population. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of red-throated diver (breeding) in Europe is High.

This assessment indicates there is an expectation of red-throated diver (breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of red-throated diver (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have either threats and high or medium impacts on relevant populations of red-throated diver when foraging in inshore waters during the pressures breeding season (Furness, 2016). In particular, red-throated divers exhibit high sensitivity to visual disturbance associated with shipping or recreational craft (Mendel et al, 2008; Dierschke et al, 2012; Jarrett et al, 2018) and in the non-breeding season are vulnerable to displacement from installations such as offshore wind farms (Furness et al, 2013; Garthe & Hüppop, 2004; Dierschke et al, 2012). However, the impacts of displacement are uncertain (Dierschke et al, 2017) and during the breeding season their more restricted distribution within sheltered inshore waters will limit potential exposure to such developments. Red-throated diver are also considered vulnerable to pressures including displacement and impacts on prey availability and foraging behaviour associated with aggregate extraction in UK waters (Cook et al, 2010). They are also susceptible to impacts associated with fisheries, both through removal of prey (Guse et al, 2009) and entanglement in fishing nets (Mendel et al, 2008; Dierschke et al, 2012; ICES, 2013; Žydelis et al, 2013). Red-throated divers In Britain may be moderately vulnerable (sensitivity scores in top 50% of species rankings) to bycatch in surface gears, but their exposure to such gears during the breeding season is unclear and there is little empirical evidence of bycatch levels (Bradbury et al, 2017).

Breeding red-throated diver populations have been identified by several authors as subject to significant changes associated with climate change, but the direction and magnitude of change is unclear (Pearce-Higgins et al, 2011; Huntly et al, 2007). Well-managed protected sites are important to promoting the resilience of species and habitats to

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the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine proposed SPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Red-throated diver exhibit both high and moderate sensitivity to a number of different pressures. Replication within OSPAR regions is recommended.

3. Contribution to Scottish SPA network

This section considers the occurrence of red-throated diver (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Red- throated diver (breeding) are being considered for inclusion at five marine proposed SPAs and one existing marine extension. They are also represented in ten existing terrestrial SPAs and in the non-breeding season in one existing estuarine SPA.

Table 3 Summary of occurrence of red-throated diver (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

East Mainland Supports c. 16.6% Red-throated diver (breeding) is Provides an example in the Birds foraging in East Coast, Shetland of the GB breeding represented within 5 proposed Northern Isles and represents Mainland Coast, Shetland population. SPAs and proposed addition to the northern extent of the are within foraging range of 1 existing marine extension and range of this species in some nesting territories 10 existing terrestrial SPAs. In Scotland. within the Otterswick and the non-breeding season red- Graveland SPA Bluemull and Supports c. 15.4% throated diver is represented at Provides an example in the Birds foraging in the Colgrave Sounds of the GB breeding one existing estuarine SPA. Northern Isles and represents Bluemull and Colgrave population. the northern extent of the Sounds are within foraging Replication of this feature in the range of this species in range of the nesting network is proposed in OSPAR Scotland. territories at Otterswick and Regions II and III Graveland SPA

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Proposed SPAs Representation Replication Geographic range Linkages

Scapa Flow Supports c. 7.6% Provides an example in the Birds foraging in Scapa of the GB breeding Northern Isles and represents Flow are within foraging population. a core part of the range of range of the nesting this species in Scotland. territories at Hoy SPA and Orkney Mainland Moors SPA. North Orkney Supports c. 4.4% Provides an example in the Birds foraging in North of the GB breeding Northern Isles and represents Orkney are within foraging population. a core part of the range of range of the nesting this species in Scotland. territories at Orkney Mainland Moors SPA. West Coast of Supports c. 4.5% Provides only example in the Birds foraging in the West the Outer of the GB breeding Outer Hebrides, a core part Coast of the Outer Hebrides Hebrides population. of the range of this species in are within foraging range of Scotland. the nesting territories at Mointeach Scadabhaigh SPA Rum (existing Supports c. 1.4% Provides only example in the Birds foraging in the marine marine of the GB breeding Inner Hebrides, a core part of extension to Rum SPA are extension) population. the range of this species in within foraging range of the Scotland. nesting territories on Rum SPA.

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4. Summary

The species assessment indicates there is an expectation of red-throated diver (breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

The Scottish SPA network includes six marine pSPAs2 for red-throated diver (breeding) and 10 existing terrestrial SPAs. The marine proposed sites support up to 49.9% of the GB breeding population with proposed SPAs with replication in both OSPAR regions II and III. The locations of the proposed SPAs reflect the geographic range and variation of red- throated diver (breeding) in Scotland. The major breeding populations in the Northern isles (41% of GB total – Dillon et al, 2009) and Outer and Inner Hebrides (43% of GB total – Dillon et al, 2009) are represented, but was not considered feasible to identify marine foraging aggregations for the more dispersed Scottish mainland breeding population (Black et al, 2015). The proposed SPAs also reflect the varied environments in which breeding red- throated divers occur (e.g. from the very sheltered waters of sites such as Scapa Flow to more exposed locations such as the West Coast of the Outer Hebrides).

The number and distribution of proposed SPAs for red-throated diver (breeding) in the Scottish network, as summarised above and in Table 3, is consistent with species assessment (Table 1) but exceeds the minimum level of representation in OSPAR Region II.

Replication in both OSPAR regions is considered appropriate because red-throated diver is an Annex 1 species and there is evidence that red-throated diver (breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of red-throated diver (breeding) to such threats and pressures.

Furthermore, all of the pSPAs are within foraging range of existing terrestrial SPAs in Scotland. Inclusion of the six marine pSPAs in the network provides added conservation value by safeguarding marine habitats supporting prey species used by foraging red- throated divers (breeding) from existing terrestrial SPAs.

There is local geographic replication within OSPAR Region II in the Northern Isles where there are four pSPAs for red-throated diver (breeding); two in Orkney, at North Orkney and Scapa Flow, and two in Shetland, at East Mainland Coast, Shetland pSPA and Bluemull and Colgrave Sounds pSPA. North Orkney pSPA and Scapa Flow pSPA represent a core part of the range of this species in Scotland and together support up to 12% of the GB population. East Mainland Coast, Shetland pSPA and Bluemull and Colgrave Sounds pSPA represent the northern extent of red-throated diver, supporting 32% of the GB population.

5. Conclusion

The number and distribution of marine proposed SPAs for red-throated diver (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of red-throated diver (breeding) in Europe.

No further SPA provision is considered necessary for red-throated diver (breeding) however; a review of the level of representation in the Northern Isles is required by the Advisory Panel.

2 Includes 5 pSPAs and the addition of red-throated diver to one existing marine extension.

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6. References

BirdLife International, 2004. Birds in Europe: population estimates, trends and conservation status. Cambridge, UK: BirdLife International. BirdLife Conservation Series No. 12.

BirdLife International, 2018. Species factsheet, Gavia stellata. http://www.birdlife.org

Black, J., Dean B.J., Webb A., Lewis, M., Okill, D. & Reid, J.B. 2015. Identification of important marine areas in the UK for red-throated divers (Gavia stellata) during the breeding season. JNCC Report No 541.

Dierschke, V., Exo, K-M., Mendel, B. & Garthe, S. 2012. Threats for red-throated divers Gavia stellata and black-throated divers G. arctica in breeding, migration and wintering areas: a review with special reference to the German marine areas. Vogelwelt, 133, 163-194

Dierschke, V., Furness, R.W., Gray, C.E., Petersen, I.K., Schmutz, J., Zydelis, R. & Daunt, F. 2017. Possible Behavioural, Energetic and Demographic Effects of Displacement of Red- throated Divers. JNCC Report No. 605. JNCC, Peterborough.

Dillon, I.A., Smith, T.D., Williams, S.J., Haysom, S. & Eaton, M.A. 2009. Status of Red‐ throated Divers Gavia stellata in Britain in 2006. Bird Study, 56, 2,147-157

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66

Garthe, S. & Hüppop, O. 2004. Scaling possible adverse effects of marine wind farms on seabirds: developing and applying a vulnerability index. Journal of Applied Ecology, 41, 724-734

Guse, N., Garthe, S. & Schirmeister, B. 2009. Diet of red-throated divers Gavia stellata reflects the seasonal availability of Atlantic herring Clupea harengus in the southwestern Baltic Sea. Journal of Sea Research, 62, 268-275

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Hagemeijer, E.J.M. & Blair, M.J. (eds.). 1997. The EBCC Atlas of European Breeding Birds: their distribution and abundance. Poyser, London.

Huntley, B., Green, R.E., Collingham, Y.C. & Willis, S.G. 2007. A climatic atlas of European breeding birds. Durham University, RSPB and Lynx Edicions, Barcelona.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M. 2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Stroud, D.A., Chambers, D., Cook, S., Buxton, N., Fraser, B., Clement, P., Lewis, P., McLean, I., Baker, H. & Whitehead, S. (eds.). 2001. The UK SPA network: its scope and content. JNCC, Peterborough. www.jncc.gov.uk/page-2970

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-88

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Red-throated diver (non-breeding)

1. Introduction

Red-throated diver is an Annex 1 species. Red-throated diver (non-breeding) is being considered for inclusion within three marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for red-throated diver (non-breeding)

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2. Species account

Table 1 Summary of status of red-throated diver (non-breeding)

Species’ status Score Notes

GB marine Restricted Red-throated diver (non-breeding) have a restricted distribution in the GB marine environment (JNCC distribution range score 48.4%1). Red-throated diver occur in coastal waters throughout Britain in winter (Austin et al, 2017; Balmer et al, 2014) but also range further offshore (O’Brien et al, 2008). Significance of Low The majority of the GB wintering population of 17,000 occur off eastern England, with 44% in the Scotland’s seas Greater Thames area (O’Brien et al, 2008). Other notable concentrations occur off parts of Wales and in GB context in Liverpool Bay. Scotland holds some 2000 of the GB wintering population concentrated in east coast Firths and coasts bordering the North Channel in the southwest (ibid; Bradbury et al, 2017). GB contribution Medium The GB wintering population of this Annex 1 species is 17,000 birds (O’Brien et al, 2008; Musgrove et to biogeographic al, 2013) equivalent to approximately 4-12% of the biogeographic (North-west Europe) population population estimated at 150,000 - 450,000 birds (Wetlands International, 2015 & 2018).

Red-throated diver breed across the northern hemisphere generally north of 60°, and migrate south in winter to ice-free waters extending in Europe as far south as the coast of Portugal, the Mediterranean Sea and Black Sea. Scottish-breeding birds are thought to travel shorter distances between breeding and wintering areas than other European birds to wintering areas off both east and west coasts of Britain and Ireland (Okill, 1994). Birds from breeding grounds in Scandinavia and the Baltic states are thought to migrate mainly to the southern North Sea in winter (Wright et al, 2012; O’Brien et al, 2008); while birds from Greenland have been recovered in Scotland (Wernham et al, 2002). Furness (2015) highlights the importance of Scottish wintering areas to the UK (Scottish) breeding population. European Depleted The European population conservation status is Depleted (BirdLife International, 2017). population conservation The global conservation status is Least Concern; this reflects the very large size and range of the status global population (BirdLife International, 2018)

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Species’ status summary and Red-throated diver (non-breeding) have a Restricted distribution in GB inshore waters, mainly in assessment of level of England. GB is of Medium importance to the biogeographic wintering population of this Annex 1 representation in Scottish species and the European population status is Depleted. Accordingly, the overall assessment of the SPA network. relative value of protected areas in Scotland’s marine environment to conservation of red-throated diver (non-breeding) in Europe is Medium.

This assessment indicates there is an expectation of red-throated diver (non-breeding) being represented once or twice in each OSPAR region overlapping its Scottish distribution; replication of representation in regions would enhance species’ resilience.

Table 2 Vulnerability of red-throated diver (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have either threats and high or medium impacts on relevant populations of red-throated diver (non-breeding) (Furness, 2016). Red-throated pressures divers exhibit high sensitivity to visual disturbance associated with shipping or recreational craft (Mendel et al, 2008; Dierschke et al, 2012; Jarrett et al, 2018) and are vulnerable to displacement from offshore wind farms (Furness et al, 2013; Garthe & Hüppop, 2004; Dierschke et al, 2012; Furness et al, 2013), although the impacts of displacement are uncertain (Dierschke et al, 2017). They are also considered vulnerable to pressures including displacement and impacts on prey availability and foraging behaviour associated with aggregate extraction in UK waters (Cook et al, 2010). Red-throated divers (non-breeding) are also susceptible to impacts associated with fisheries, both through removal of prey (Guse et al, 2009) and entanglement in fishing nets (Mendel et al, 2008; Dierschke et al, 2012; ICES, 2013). Red-throated diver populations wintering in coastal waters off eastern and south-west Britain may be moderately vulnerable (sensitivity scores in top 50% of species rankings) to bycatch in surface gears in the winter months, but there is little empirical evidence of bycatch levels (Bradbury et al, 2017).

Whilst there is no specific evidence on the impacts of climate change to red-throated divers (non-breeding), it is recognised that well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine proposed SPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Red-throated diver populations are vulnerable to high or medium impacts from a number of different threats and pressures. Replication within OSPAR regions is recommended.

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3. Contribution to Scottish SPA network

This section considers the occurrence of red-throated diver (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Red-throated diver (non-breeding) is being considered for inclusion at three marine proposed SPAs and is a feature of one existing estuarine SPA, which is contiguous with one of the marine pSPAs. In addition, during the breeding season, red-throated diver is represented in ten terrestrial SPAs.

Table 3 Summary of occurrence of red-throated diver (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed Representation Replication Geographic range Linkages SPAs

Outer Firth of Supports up to Red-throated diver Provides an example Red-throated diver (non-breeding) is a feature of Forth & St 5.0% of the GB (non-breeding) is on the east mainland the estuarine Firth of Forth SPA which is Andrews Bay non-breeding represented within 3 coast and represents contiguous with Outer Firth of Forth & St Andrews Complex population. marine proposed the core part of the Bay Complex pSPA. The red-throated diver SPAs and one range of this species population in this area will use both (intertidal) existing estuarine in Scotland. estuarine and (sub-tidal) marine environments. Moray Firth Supports up to SPA (Firth of Forth). Provides an example Limited recoveries of ringed adults and chicks 1.9% of the GB on the east mainland from the Shetland breeding population indicates non-breeding During the breeding coast and represents that red-throated divers breeding in Scotland population. season red-throated the northern extent of winter over a substantial area including both east diver is represented in the range of this and west coasts of Britain and Ireland (Okill, 10 existing terrestrial species in Scotland. 1994). Recent tracking studies of wintering birds Solway Firth Supports up to SPAs. Provides the only captured in the German North Sea indicate that 3.1% of the GB example of this individual birds exhibit high levels of consistency non-breeding Replication of this species on the west in migration routes, breeding, wintering & population. feature in the network coast of Scotland. moulting areas (Kleinschmidt et al, 2017). Any is proposed in direct linkages between terrestrial and marine OSPAR Region II SPAs for red-throated divers in Scotland are as yet unclear (Furness, 2015).

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4. Summary

The Scottish SPA network includes three marine proposed SPAs for red-throated diver (non- breeding) and one existing estuarine SPA. The marine proposed sites support up to 10% of the GB non-breeding population with proposed sites in OSPAR Regions II and III and replication in OSPAR Region II. The locations of the proposed sites reflect the full geographic range and variation of red-throated diver (non-breeding) in Scotland’s marine environment, including both the east and south-west coasts.

The number and distribution of marine proposed sites for red-throated diver (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the species account (Table 1).

Replication in OSPAR Region II is considered appropriate because red-throated diver is an Annex 1 species and there is evidence that red-throated diver (non-breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of red-throated diver (non-breeding) to such threats and pressures.

Together with the existing (estuarine) Firth of Forth SPA, inclusion of the Outer Firth of Forth and St Andrews Bay Complex pSPA in the network provides added conservation value by encompassing the full range of habitats used by red-throated diver (non-breeding) in the Firth of Forth. There is however insufficient evidence to assess linkages among the three marine proposed SPAs and the terrestrial SPAs for breeding red-throated diver.

5. Conclusion

The number and distribution of marine proposed SPAs for red-throated diver (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of red-throated diver (non-breeding) in Europe.

No further SPA provision is considered necessary for red-throated diver (non-breeding).

6. References

Balmer, D., Gillings, S., Caffrey, B., Swann, B., Downie, I. & Fuller, R. 2014. Bird Atlas 2007-11: The Breeding and Wintering Birds of Britain and Ireland. BTO, BirdWatch Ireland, and SOC

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BirdLife International, 2018. Species factsheet, Gavia stellata. http://www.birdlife.org

Dierschke, V; Furness, R.W., Gray, C.E.; Petersen, I.K., Schmutz, J., Zydelis, R. & Daunt, F. 2017. Possible Behavioural, Energetic and Demographic Effects of Displacement of Red- throated Divers. JNCC Report No. 605. JNCC, Peterborough.

Furness, R.W., Wade, H.M. & Masden, E.A. 2013. Assessing vulnerability of marine bird populations to offshore wind farms. Journal of Environmental Management, 119, 56-66

Garthe, S. & Hüppop, O. 2004. Scaling possible adverse effects of marine wind farms on seabirds: developing and applying a vulnerability index. Journal of Applied Ecology, 41, 724-734

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark. ICES CM 2013/ACOM: 77.

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M. 2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

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Kleinschmidt B., Dorsch, M., Žydelis, R., Heinänen, S., Morkūnas, J., Burger, C., Nehls, G. & Quillfeldt, P. 2017. Site fidelity and temporal consistency of red- throated divers (Gavia stellata) during migration, moult & wintering. Poster presented at BOU 2017 Annual Conference: From avian tracking to population processes, University of Warwick, UK https://www.researchgate.net/publication/315800704_Site_fidelity_and_temporal_consistenc y_of_red-throated_divers_Gavia_stellata_during_migration_moult_wintering

O'Brien, S.H., Wilson, L.J., Webb, A. & Cranswick, P.A. 2008. Revised estimate of numbers of wintering Red-throated Divers Gavia stellata in Great Britain, Bird Study, 55, 2, 152-160

Okill, J.D. 1994. Ringing recoveries of red‐throated divers Gavia stellata in Britain and Ireland. Ringing & Migration, 15, 2, 107-118

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wernham, C.V., Toms, M.P., Marchant, J.H., Clark, J.A., Siriwardena, G.M. & Baillie, S.R. (eds.) 2002. Migration Atlas: movements of birds of Britain and Ireland. Poyser, London

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

316

Roseate tern (breeding)

1. Introduction

Roseate tern is an Annex 1species. No marine proposed SPAs have been identified for roseate tern (breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of roseate tern (breeding).

Species’ status Score Notes

Pattern of N/A no The Seabird 2000 national census of breeding seabirds in Britain and Ireland found 52 pairs of roseate occurrence in GB roseate tern in GB. The population in Ireland was much larger with 738 pairs, nearly all at two large colonies in marine terns in the southeast. The majority (33 pairs) in GB were on Coquet Island in northeast England and there environment and Scotland were 14 pairs in Scotland, all but one at two sites in the Forth of Forth (Mitchell et al, 2004). relative importance of This represented a low point in the GB population, which in 1969/70 stood at 690 pairs. Since 2000 Scotland there has been some recovery in the GB population, largely as a result of conservation measures in the wintering grounds in west Africa. This recovery has seen a further concentration of the GB roseate tern population at Coquet island, which in 2015 held 111 of the 113 pairs in GB. Over the same period, the main Scottish breeding sites have been abandoned, and Scotland’s contribution to the GB roseate tern population is currently limited to single pairs occasionally frequenting other tern colonies1. A similar pattern of recovery and redistribution to that in GB has been seen in Ireland where over 90% of the population (over 1400 pairs in 2014) is concentrated at a single colony.

Breeding roseate terns typically forage within 20km of their colonies (Wilson et al, 2014; Thaxter et al, 2012); hence birds from the Coquet Island are not anticipated to use Scottish waters. The potential contribution of Scotland to continuing recovery of the GB population is uncertain.

1 http://jncc.defra.gov.uk/page-2891

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GB contribution Medium The most recent (2015) estimate of the GB breeding population of this Annex 1 species is 113 pairs to biogeographic which represents 3.9 – 4.9% of the biogeographic population (dougalli subspecies Europe) population estimated at 2,300-2,900 pairs (BirdLife International, 2018).

This species has a vast but sparsely distributed global range including the east coast and offshore islands of Northern, Central and northern South America, the Caribbean, U.K., France, Ireland, Oman, South Africa, east Africa, island groups in the Atlantic (e.g. Azores), Pacific (e.g. Fiji) and Indian (e.g. Seychelles) Oceans, Sri Lanka, Japan, Taiwan and Australia (BirdLife International, 2018). European Rare The European conservation status for Roseate tern is Rare and the global status is Least Concern. population conservation (BirdLife International, 2017 & 2018). This reflects the relatively small size of the European population status (c. 2.5% of global) of this very wide-ranging and abundant species. Species’ status summary and The GB population of roseate tern (breeding) is of Medium importance to the Rare European assessment of level of population. Scotland currently holds 0% of the roseate tern breeding population in GB and representation in Scottish Scotland’s seas are beyond the typical foraging range of birds at the main GB colony on SPA network. Coquet Island, which held over 98% of the GB population in 2015. Therefore, it is not currently feasible to identify pSPAs for roseate tern in Scotland.

Table 2 Vulnerability of roseate tern (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have either high and/or high or medium impacts on relevant populations of Roseate tern (breeding) (Furness, 2016). In particular, roseate tern medium populations are dependent on food-fish stocks such as sandeels, sprats and herring within foraging range of their impacts. colonies (Newton, 2004) and hence are potentially vulnerable to changes to population dynamics or stock depletions associated with commercial fisheries (Furness, 2002) or climate change (Arnott & Ruxton, 2002). Roseate tern have been assessed as moderately sensitive to changes in water turbidity associated with activities such as marine aggregate extraction operations, but impacts on populations are undocumented (Cook & Burton, 2010). In addition to pressures in their foraging grounds, roseate terns are also vulnerable to human disturbance, mammalian predators, competition for nest sites with gulls and tidal flooding at their nest sites (Newbury, 1999; Newton, 2004; OSPAR Commission, 2009).

As outlined above, roseate tern colonies may be vulnerable to both direct and indirect impacts of climate change, but insufficient data are available to enable predictions of impacts of climate change on UK populations (Pearce-Higgins et al, 2011).

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3. Summary

It is not currently feasible to identify pSPAs for roseate tern in Scotland as the species no longer regularly breeds in Scotland and Scotland’s seas are outwith the foraging range of the main GB colony at Coquet Island, which holds over 98% of the GB population.

However, the breeding population of roseate tern in GB (and Ireland) is continuing to recover, such that it is possible that former breeding sites within the Firth of Forth SPA may be recolonized in future. In this event, consideration should be given to adding roseate tern as a qualifying feature of the Outer Firth of Forth and St Andrews Bay Complex pSPA to protect foraging areas used by breeding roseate tern.

4. Conclusion

Marine SPA provision is currently not realistic. However, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing roseate tern (breeding) populations at the wider seas/ ecosystem level.

5. References

Arnott, S.A. & Ruxton, G.D. 2002. Sandeel recruitment in the North Sea: demographic, climatic and trophic effects. Marine Ecology Progress Series, 238, 199-210.

BirdLife International, 2018. Species factsheet, Sterna dougallii. http://www.birdlife.org

Cook, A.S.C.P. & Burton, N.H.K. 2010. A review of the potential impacts of marine aggregate extraction on seabirds. Marine Environment Protection Fund Project 09/P130. .British Trust for Ornithology. Thetford, Norfolk, UK.

Furness, R.W. 2002. Management implications of interactions between fisheries and sandeel-dependent seabirds and seals in the North Sea. ICES Journal of Marine Science, 59, 261-269.

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

Newbury, P. 1999. International (East Atlantic) Action Plan for Roseate Tern Sterna dougallii. European Commission. http://ec.europa.eu/environment/nature/conservation/wildbirds/action_plans/docs/sterna_dou galii.pdf

Newton, S.F. 2004. Roseate Tern Sterna dougallii. Pp. 302-314. In: Mitchell, P.I., Newton, S., Ratcliffe, N. & Dunn, T.E. (eds.) Seabird Populations of Britain and Ireland. Poyser, London.

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OSPAR Commission 2009. Background document for roseate tern (Sterna dougallii). OSPAR Commission Biodiversity Series.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wilson L.J., Black J., Brewer, M.J., Potts, J. M., Kuepfer, A., Win I., Kober K., Bingham C., Mavor R. & Webb A. 2014. Quantifying usage of the marine environment by terns Sterna sp. around their breeding colony SPAs. JNCC Report No. 500

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Sandwich tern (breeding)

1. Introduction

Sandwich tern is an Annex 1 species. Sandwich tern (breeding) is being considered for inclusion within a proposed marine extension to one existing SPA. This is shown in Figure 1.

Figure 1 Map showing proposed marine extension for Sandwich tern (breeding)

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2. Species account Table 1 Summary of status of Sandwich tern (breeding)

Species’ status Score Notes

GB marine Highly Breeding Sandwich terns forage in inshore waters, typically within 30-50km of their colonies distribution restricted (Wilson et al, 2014; Thaxter et al, 2012). This is reflected in the observed at-sea distribution, with very few high density areas, most notably around The Wash, associated with major colonies (Bradbury et al, 2017). Significance of Low Sandwich terns breeding are patchily distributed around the coast of GB in a small number of mainly Scotland’s seas large colonies, mainly on eastern coasts (Mitchell et al, 2004). The Seabird 2000 national census of in GB context breeding seabirds in Britain and Ireland found a total GB population of 10,540 pairs of which 1,070 (10%) were in Scotland, the majority at just two colonies (Sands of Forvie in Aberdeenshire and Isle of May in the Forth of Forth (Mitchell et al, 2004). GB contribution Moderate The most recent (1998-2002) estimate of the GB breeding population of this Annex 1 species is to biogeographic 10,540 pairs, which represents 13.9 – 15.9% of the biogeographic population (sandvicensis sub- population species Western Europe/West Africa) estimated at 69,000 - 79,000 pairs (Mitchell et al, 2004).

Sandwich tern is found in Europe, Africa, western Asia, and the southern Americas. In Europe it breeds on the coast of much of Europe east to the Caspian Sea, wintering from the Caspian, Black and Mediterranean Seas to the coasts of western and southern Africa, and from the south Red Sea to north-west India and Sri Lanka (BirdLife International, 2018). European Least The global and European conservation status for Sandwich tern is Least Concern (Secure) (Birdlife population concern International, 2017 & 2018). conservation status Species’ status summary and The GB breeding population of Sandwich tern is of Moderate importance to the biogeographic assessment of level of population of this Annex 1 species and the European population status is considered least Concern. representation in Scottish Sandwich tern (breeding) have a highly restricted distribution in GB waters, with the majority of the SPA network. population in England.

Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of Sandwich tern (breeding) in Europe is Low.

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This assessment indicates there is an expectation of Sandwich tern (breeding) being represented once or twice in the Scottish SPA network.

Table 2 Vulnerability of Sandwich tern (breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have either high or medium threats and impacts on relevant populations of Sandwich tern (breeding) (Furness, 2016). In particular, Sandwich terns are pressures vulnerable to depletion of food-fish stocks, such as sandeels and Clupeidae (Furness, 2002; Stienen et al, 2000; Garthe & Flore, 2007). Sandwich tern population declines in the Netherlands have been linked to increases in turbidity associated with dredging of sediments (Essink, 1999).

Sandwich terns are potentially sensitive to bycatch in longline fisheries (ICES, 2013) but are not identified as among the more sensitive species to bycatch in fisheries operating in UK waters (Bradbury et al, 2017).

Sandwich tern populations could potentially be impacted by climate change both through impacts on fish prey species (Arnott & Ruxton, 2002) and effects of increased storminess on nesting habitat or on levels of kleptoparistism by gulls (Stienen et al, 2001) but populations in the UK are not predicted to change by more than 25% by 2050 (Pearce-Higgins et al, 2011). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Sandwich tern populations are vulnerable to high or medium impacts from to a number of different threats and pressures. Replication within OSPAR regions should be considered.

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3. Contribution to Scottish SPA network

This section considers the occurrence of Sandwich tern (breeding) within the marine proposed SPAs and existing SPAs in Scotland. Sandwich tern (breeding) is being considered for inclusion in a proposed marine extension to the existing Ythan Estuary, Sands of Forvie and Meikle Loch SPA, where it is a feature of the breeding colony. The proposed marine extension encompasses the foraging area used by breeding terns from the colony SPA. It is also a feature at two other existing colony SPAs, one of which has a marine extension for maintenance behaviours such as preening, loafing and roosting.

Table 3 Summary of occurrence of Sandwich tern (breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

Ythan Estuary, Supports Sandwich tern (breeding) is Provides only example for Birds foraging in the Sands of Forvie and approximately 7% represented within one this species in Scotland. proposed marine extension Meikle Loch (marine of the GB breeding proposed marine extension are within foraging range of extension) population. and is represented at 3 the breeding colony at the existing colony SPAs, one of existing Ythan Estuary, which has a marine Sands of Forvie and Meikle extension. However, Loch SPA (Wilson et al, Sandwich tern is not the 2014). species determining the extension.

No sites were identified in OSPAR Region III.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of Sandwich tern (breeding) being represented once or twice in the Scottish SPA network.

The Scottish SPA network includes one proposed marine extension to an existing colony SPA for Sandwich tern (breeding) and two other existing colony SPAs. The proposed marine extension in OSPAR Region II is functionally linked to the largest breeding colony of Sandwich tern in Scotland, at the Ythan Estuary, Sands of Forvie and Meikle Loch SPA (Wilson et al, 2014), which supports an estimated 7% of the GB breeding population.

The number and distribution of marine proposed SPAs for Sandwich tern (breeding) in the Scottish network, as summarised above and in Table 3, is consistent with the species assessment (Table 1).

Replication in the network would be desirable because Sandwich tern is an Annex 1 species and because there is evidence that Sandwich tern populations are potentially vulnerable to activities in their feeding grounds that may increase water turbidity and to changes in prey stocks driven by climate change and/or commercial fisheries. Site-based protection of core foraging areas complements wider seas measures and is considered an appropriate conservation measure to enhance resilience of Sandwich tern (breeding). However, neither of the other existing Scottish SPAs (Forth Islands and Loch of Strathbeg) of which Sandwich tern (breeding) are a qualifying feature were included in the process to identify marine sites. This was because these sites were considered no longer regularly occupied (Wilson et al, 2014).

Inclusion of the proposed marine extension in the network provides added conservation value by safeguarding marine habitats supporting prey species used by Sandwich tern (breeding) from the existing Ythan Estuary, Sands of Forvie and Meikle Loch SPA.

5. Conclusion

The number and distribution of marine proposed SPAs for Sandwich tern (breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of Sandwich tern (breeding) in Europe.

No further SPA provision is considered necessary for Sandwich tern (breeding) however, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing Sandwich tern (breeding) populations at the wider seas/ecosystem level.

6. References

Arnott, S.A. & Ruxton, G.D. 2002. Sandeel recruitment in the North Sea: demographic, climatic and trophic effects. Marine Ecology Progress Series, 238, 199-210

BirdLife International, 2018. Species factsheet, Thalasseus sandvicensis. http://www.birdlife.org

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Essink, K. 1999. Ecological effects of dumping of dredged sediments; options for management. Journal of Coastal Conservation, 5, 69-80.

Furness, R.W. 2002. Management implications of interactions between fisheries and sandeel-dependent seabirds and seals in the North Sea. ICES Journal of Marine Science, 59, 261-269.

Garthe, S. & Flore, B-O. 2007. Population trend over 100 years and conservation needs of breeding Sandwich terns (Sterna sandvicensis) on the German North Sea coast. Journal of Ornithology 148, 215-227.

ICES, 2013. Report of the Workshop to review and advise on Seabird Bycatch (WKBYCS) 14-18 October 2013, Copenhagen, Denmark

Mitchell, P.I., Newton, S.F., Ratcliffe, N. & Dunn, T.E. (eds.) 2004. Seabird Populations of Britain and Ireland. Poyser, London.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Stienen, E.W.M., Van Beers, P.W.M., Brenninkmeijer, A., Habraken, J.M.P.M., Raaijmakers, M.H.J.E. & Van Tienen, P.G.M. 2000. Reflections of a specialist: patterns in food provisioning and foraging conditions in Sandwich terns Sterna sandvicensis. Ardea, 88, 33- 49.

Stienen, E.W.M., Brenninkmeijer, A. & Geschiere, C.E. 2001. Living with gulls: the consequences for Sandwich terns of breeding in association with black-headed gulls. Waterbirds, 24, 68-82.

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Slavonian grebe (non-breeding)

1. Introduction

Slavonian grebe is an Annex 1 species. Slavonian grebe (non-breeding) is being considered for inclusion within 7 marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing marine proposed SPAs for Slavonian grebe (non-breeding)

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2. Species account

Table 1 Summary of status of Slavonian grebe (non-breeding)

Species’ status Score Notes

GB marine Restricted Slavonian grebes have a restricted winter distribution around coastal waters across GB (present in distribution 38.8% of coastal squares in 2007-11 Atlas1 and in an average of 17.3% of coastal core WeBS count sectors counted between 2011 and 20152). Significance of High Scotland holds the largest numbers and concentrations of Slavonian grebe (69% of coastal core Scotland’s seas WeBS count sectors with 10 or more birds and 100% of sectors with 50 or more birds2), with particular in GB context concentrations in sheltered waters in the Northern Isles, northwest Scotland including Outer Hebrides, Moray Firth, Firth of Forth and Kintyre (Balmer et al, 2014). GB contribution Medium The estimated GB wintering population of this Annex 1 species is 1,100 birds (Musgrove et al, 2013) to biogeographic which is approximately 20% of the small biogeographic (North-west Europe (large-billed)) population population of 4,600 – 6,800 birds (Wetlands International, 2015 & 2018) Over 90% of the global population breed and winter in North America. In the Palearctic this species breeds from Iceland and the Baltic to Kamchatka, Russia, wintering from the North Sea to the Caspian Sea and off Japan to China (BirdLife International, 2018). European Near The European conservation status is Near Threatened (BirdLife International, 2017). population Threatened The global conservation status is Vulnerable, reflecting a major decrease over the last 40 years in the conservation North American population associated human disturbance, forestry operations around breeding lakes, status fluctuating water levels, and the stocking of lakes with rainbow (BirdLife International, 2018) Species’ status summary and Slavonian grebe (non-breeding) have a Restricted distribution in GB inshore waters, with the majority assessment of level of of the wintering population found in Scotland. The GB population is of Medium importance to the representation in Scottish small biogeographic population of this Annex 1 species and its European population status is Near SPA network. Threatened. Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of Slavonian grebe (non-breeding) is Very High.

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This assessment indicates there is an expectation of Slavonian grebe (non-breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of Slavonian grebe (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to Furness (2016) did not identify any documented evidence of pressures or threats operating within UK waters likely threats and to have either high or medium population level impacts specifically on Slavonian grebe during the non-breeding pressures season. However a number of sources highlight the high sensitivity of Slavonian grebe to vessel movements (Mendel et al, 2008; Jarrett et al, 2018) and they are assessed as vulnerable to disturbance and changes in water clarity associated with aggregate extraction or dredging (Cook & Burton, 2010). Slavonian grebes (non-breeding) are also susceptible to entanglement in fishing nets (Mendel et a,l 2008); populations wintering in coastal waters off eastern and Britain may be moderately vulnerable (sensitivity scores in top 50% of species rankings) to bycatch in surface gears, but there is little empirical evidence of bycatch levels (Bradbury et al, 2017).

3. Contribution to Scottish SPA network

This section considers the occurrence of Slavonian grebe (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Slavonian grebe (non-breeding) is being considered for inclusion at seven marine proposed SPAs and is a feature of one existing estuarine SPA, which is contiguous with one of the marine pSPAs.

Table 3 Summary of occurrence of Slavonian grebe (non-breeding) within proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

East Mainland Coast, Supports c. 4.9 % of Slavonian grebe (non- Provides an example in the No known linkages Shetland the GB non-breeding breeding) is Northern Isles and represents population. represented within 7 the northern extent of the range proposed SPAs and of this species in Scotland. one existing estuarine

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Proposed SPAs Representation Replication Geographic range Linkages

North Orkney Supports c. 10.9 % of SPA. Provides an example in the No known linkages the GB non-breeding Replication of this Northern Isles and represents a population. feature in the marine core part of the range of this network is proposed species in Scotland. Scapa Flow Supports c. 12.3 % of in OSPAR Regions II Provides an example in the No known linkages the GB non-breeding and III. Northern Isles and represents a population. core part of the range of this species in Scotland. Moray Firth Supports c. 3.9 % of Provides an example on the Linkages between the GB non-breeding east mainland coast in the core wintering and breeding population. part of the range of this species grounds are presently Scotland. unknown. However, the Moray Firth pSPA is the closest wintering site to all 6 existing freshwater SPA breeding sites. Outer Firth of Forth & St Supports c. 2.7 % of Provides an example on the Slavonian grebe (non- Andrews Bay Complex the GB non-breeding east mainland coast and breeding) is a feature of population. represents the southern extent the Firth of Forth SPA of the range of this species in which is contiguous with Scotland. this marine proposed SPA. Sound of Gigha Supports c. 3.4 % of Provides only example on the No known linkages the GB non-breeding west mainland coast and population. represents the southern extent of the range of this species in Scotland.

West Coast of the Outer Supports c. 4.6 % of Provides only example in the No known linkages Hebrides the GB non-breeding Outer Hebrides, a core part of population. the range of this species in Scotland.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of Slavonian grebe (non-breeding) being included in all pSPAs where it has been identified as a qualifying feature and of being represented more than twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

The marine proposed SPA network includes seven pSPAs for Slavonian grebe (non- breeding) of which five are in OSPAR Region II and two in Region III. Together they support an estimated 42.7% of the GB population of this Annex 1 species. The proposed SPAs reflect the full geographic range of non-breeding Slavonian grebe in Scotland from East Mainland Coast, Shetland in the far north east to the Sound of Gigha in southern Argyll and Moray Firth and Outer Firth of Forth & St Andrews Bay Complex on the east coast. They also reflect the varied environments in which Slavonian grebe occur (e.g. from the exposed West Coast of the Outer Hebrides to the more sheltered waters of sites such as Scapa Flow.

The number and distribution of proposed SPAs for Slavonian grebe (non-breeding) in the Scottish network, as summarised above and in Table 3, is consistent with the species assessment (Table 1).

Slavonian grebe (non-breeding) is proposed for inclusion in all proposed SPAs where it has been identified as a qualifying feature and is represented more than once in each OSPAR region. Replication of sites ensures the full extent of the Scottish geographic range is encompassed and enhances network resilience for this Annex 1 species. There is no direct evidence of high or medium impacts to Slavonian grebe (non-breeding) population in response to threats and pressures and therefore no additional replication beyond the species assessment is considered necessary.

Inclusion of the Outer Firth of Forth and St Andrews Bay Complex pSPA in the network provides added conservation value by encompassing the full range of habitats used by Slavonian grebe (non-breeding) also present in the Firth of Forth SPA. The marine pSPA network may also include wintering areas for Slavonian grebes breeding at a number of freshwater SPAs in the Scottish Highlands. However, movements between breeding and wintering areas and during the non-breeding season are unknown.

There is local geographic replication within OSPAR Region II in the Northern Isles, where there are three pSPAs for Slavonian grebe (non-breeding); two in Orkney, at North Orkney and Scapa Flow, and one in Shetland. The East Mainland Coast, Shetland pSPA represents the northern extent of this species in GB. North Orkney pSPA and Scapa Flow pSPA represent the most concentrated wintering populations in Scotland, together holding 23% of the GB population. Of the two Orkney sites, Scapa Flow pSPA holds the largest number of Slavonian grebe (non-breeding) in the Scottish pSPA suite and North Orkney the second largest.

5. Conclusion

The number and distribution of marine proposed SPAs for Slavonian grebe (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of Slavonian grebe (non-breeding) in Europe.

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No further SPA provision is considered necessary for Slavonian grebe (non-breeding). However, a review of the level of representation in the Northern Isles is required by the Advisory Panel.

6. References

Balmer, D., Gillings, S., Caffrey, B., Swann, B., Downie, I. & Fuller, R. 2014. Bird Atlas 2007-11: The Breeding and Wintering Birds of Britain and Ireland. BTO, BirdWatch Ireland, and SOC

BirdLife International, 2018. Species factsheet, Podiceps auritus. http://www.birdlife.org

Jarrett, D., Cook, A.S.C.P., Woodward, I., Ross, K., Horswill, C., Dadam, D. & Humphreys, E.M. 2018. Short-Term Behavioural Responses of Wintering Waterbirds to Marine Activity (CR/2015/17). Scottish Marine and Freshwater Science, 9, No 7 https://data.marine.gov.scot/sites/default/files//SMFS%200907.pdf

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Wetlands International, 2015. Waterbird population estimates, fifth edition. Summary report. Wetlands International, Wageningen, The Netherlands

Wetlands International, 2018. Waterbird population estimates. wpe.wetlands.org

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Sooty shearwater (non-breeding)

1. Introduction

Sooty shearwater is a regularly occurring migratory species. No pSPAs have been identified for sooty shearwater (non-breeding) in the Scottish pSPA network.

2. Species account

Table 1 Summary of status of sooty shearwater (non-breeding)

Species’ status Score Notes

GB marine Widespread Sooty shearwater is a highly pelagic and very abundant species which breeds in the southern distribution hemisphere and migrates to the northern hemisphere during the austral winter. Within GB waters they

are a passage migrant. The best available evidence (Stone et al 1995; Bradbury et al, 2017) indicates a widespread but patchy distribution in GB waters (JNCC range score 95.5%1). Significance of High Zonfrillo (2007) estimates that >7,500 sooty shearwater move through Scottish waters on passage Scotland’s seas during the non-breeding season2. in GB context There are no estimates of the numbers of sooty shearwater using GB waters during their non-breeding season. However, in July and August, the highest densities occur in the Minch, around the Rockall Bank and in some areas off the north and west coasts of Scotland, with lower densities across continental shelf waters and the North Sea. During September to November the greatest densities are observed on the north and east coasts of Scotland, particularly around Orkney and Caithness, and along the north-east coast of England (Stone et al, 1995; Bradbury et al, 2017). Hence, the majority of birds in GB waters appear to occur mainly in Scottish waters.

1 Derived from the distribution models in Bradbury et al (2017) and defined as percentage of cells within the UK marine area in which the modelled density value exceeded 1% of the 95th centile density value (excluding cells in which CV was >0.5). 2 Estimate is from land-based observations and is unlikely to reflect the true abundance of this highly pelagic species.

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GB contribution Low The global (biogeographic3) population is roughly estimated to number > c. 20,000,000 individuals to biogeographic (Brooke, 2004). The vast majority of the global population are in the Pacific. Smaller breeding population populations (of c. 10 -20,000 pairs) occur in the Falkland Islands, which would equate to c. 0.25% of global estimate. The importance of GB waters to non-breeding sooty shearwater populations is unclear. Whilst the species has a very large global population, an extremely large non-breeding range, and visits GB waters on passage, tracking data suggests that birds from the Falkland Islands mainly winter in the NW Atlantic, with relatively few birds moving to NE Atlantic (Hedd et al, 2012). This could mean that GB waters are important to a relatively restricted population.

Sooty shearwaters breed in the southern hemisphere, mainly on islands off the coasts of South America, New Zealand and Australasia. In the Atlantic the species increasingly breeds on the Falkland Islands and Tristan da Cuhna. In the non-breeding season sooty shearwater range into the northern hemisphere in both the Pacific and Atlantic oceans. Sooty shearwater are often observed flying offshore in Scottish waters, mainly from July to October. The species is highly pelagic, generally avoids land and is reluctant to enter firths (Zonfrillo, 2007). European Near The global conservation status for sooty shearwater is Near Threatened (BirdLife International, 2017). population Threatened There is no European conservation status for this species. conservation status The species is classified as Near Threatened because although it has a very large global population it is thought to have undergone moderately rapid declines (BirdLife International, 2017). Species’ status summary and The global population status of sooty shearwater (non-breeding) is considered Near Threatened, assessment of level of although GB is of Low importance to the very large global population of this regularly occurring representation in Scottish migratory species. Sooty shearwater (non-breeding) have a widespread distribution in GB waters, with SPA network. the highest densities around Scotland and the north-east coast of England (Stone et al, 1995). Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of sooty shearwater (non-breeding) in Europe is Low.

This assessment indicates there is an expectation of sooty shearwater (non-breeding) being represented once or twice in the Scottish SPA network.

3 http://jncc.defra.gov.uk/pdf/sas_seabird_populations_in_the_identification_of_marine_spas.pdf

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Table 2 Vulnerability of sooty shearwater (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities in UK waters generating pressures or threats likely to have medium impacts on threats and relevant populations of sooty shearwater (non-breeding) (Furness, 2016). This includes accidental bycatch in pressures longline, trawl and gill-net fisheries (Robertson et al, 2006; Žydelis et al, 2013; Bradbury et al, 2017).

Sooty shearwater population declines at their southern hemisphere breeding grounds may be linked to climate change (Scott et al, 2008). Well-managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016). However, given the wide-ranging and pelagic nature of this species during the non-breeding season, marine pSPAs in Scotland are unlikely to be an appropriate conservation measure for this species.

Sooty shearwater (non-breeding) populations are vulnerable to medium impacts from accidental bycatch. Replication within OSPAR Regions should be considered.

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3. Summary

The species assessment indicates there is an expectation of sooty shearwater (non- breeding) being represented once or twice in the Scottish SPA network.

No sites have been identified for sooty shearwater (non-breeding) in the Scottish pSPA network.

The number and distribution of marine proposed sites for sooty shearwater (non-breeding) in the Scottish pSPA network as summarised above is below the minimum level of representation indicated by the species assessment (Table 1).

Sooty shearwater (non-breeding) are primarily vulnerable to threats and pressures that exist at the wider ecosystem level that are not judged to be most appropriately managed through site-based protection. Furthermore, sooty shearwater (non-breeding) is a globally abundant transequatorial passage migrant in Scottish waters with a very widely dispersed and unpredictable distribution meaning that marine SPA provision is unrealistic. No hotspots holding qualifying numbers of sooty shearwater were identified through analysis of the ESAS data set (Kober et al, 2010).

4. Conclusion

SPA provision is not considered an appropriate conservation measure for sooty shearwater (non-breeding) due to the widely dispersed and unpredictable nature of their distribution. However, additional and/or alternative conservation measures could be considered to address anthropogenic threats and pressures influencing sooty shearwater (non-breeding) populations at the wider seas/ecosystem level.

5. References

BirdLife International, 2017. Ardenna grisea (amended version of 2016 assessment). The IUCN Red List of Threatened Species 2017: e.T22698209A110674925. http://dx.doi.org/10.2305/IUCN.UK.2017-1.RLTS.T22698209A110674925.en.

Brooke, M. de L. 2004. Albatrosses and Petrels Across the World. Oxford University Press, Oxford.

Hedd, A., Montevecchi, W.A., Otley, H., Phillips, R.A. & Fifield, D.A. 2012. Trans-equatorial migration and habitat use by Sooty Shearwaters Puffinus griseus from theSouth Atlantic during the nonbreeding season. Marine Ecology Progress Series.

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Robertson, G., McNeill, M., Smith, N., Wienecke, B., Candy, S. & Olivier, F. 2006. Fast sinking (integrated weight) longlines reduce mortality of white-chinned petrels (Procellaria aequinoctialis) and sooty shearwater (Puffinus griseus) in demersal longline fisheries. Biological Conservation, 132, 458-471.

Scott, D., Scofield, P., Hunter, C. & Fletcher, D. 2008. Decline of sooty shearwaters, Puffinus griseus, on the Snares, New Zealand. Papers and Proceedings of the Royal Society of Tasmania, 142, 185-196.

SNH, 2016. Climate change and nature in Scotland. https://www.nature.scot/climate-change-and-nature-scotland

Zonfrillo, B. 2007. Sooty Shearwater. In Forrester, R.W. & Andrews, I.J. (eds.) The Birds of Scotland, Vol. 1: 374 – 376. Scottish Ornithologists’ Club, Aberlady.

Žydelis, R., Small, C. & French, G. 2013. The incidental catch of seabirds in gillnet fisheries: A global review. Biological Conservation, 162, 76-88.

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Velvet scoter (non-breeding)

1. Introduction

Velvet scoter is a regularly occurring migratory species. Velvet scoter (non-breeding) is being considered for inclusion within three marine proposed SPAs. These are shown in Figure 1.

Figure 1 Map showing the marine proposed SPAs for velvet scoter (non-breeding)

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2. Species account

Table 1 Summary of status of velvet scoter (non-breeding)

Species’ status Score Notes

GB marine Restricted Velvet scoter have a highly restricted distribution within GB inshore waters (present in 26% of coastal distribution squares in 2007-11 Atlas1 and in an average of 5.4% of coastal core WeBS count sectors counted between 2011 and 20152) with areas of highest abundance mostly in Scottish coasts or seas. Significance of High Velvet scoter in winter occur in small numbers fairly continuously along the North Sea and Channel Scotland’s seas coasts of Britain with a more patchy distribution in western Britain (Balmer et al, 2014) but large in GB context numbers are confined to a few locations, most notably in the Moray Firth and Firth of Forth (Balmer et al, 2014; Bradbury et al, 2017). GB contribution Low The GB wintering population estimate of this regularly occurring migratory species is currently 2,500 to biogeographic birds (Musgrove et al, 2013) which is approximately 0.55% of the biogeographic (Western Siberia population and Northern Europe) population estimated at 450,000 birds (Wetlands International, 2015 & 2018). However, more recent sources (e.g. Lawson et al, 2015) indicate that the GB wintering population may be somewhat greater than currently estimated such that the relative importance of GB waters to the population wintering in Europe may be higher than currently recognised.

Velvet scoter in this population breed in Scandinavia and western Siberia. The majority (c.82%) winter in the Baltic with smaller numbers along coasts of western Europe (BirdLife International, 2017a). Europeans Vulnerable The global and European conservation status of velvet scoter is Vulnerable (BirdLife International, population 2017a & b). conservation status Species’ status summary and Velvet scoter (non-breeding) have a Restricted occurrence in GB’s nearshore waters, with large assessment of level of aggregations occurring in a few locations, notably in Scotland. The velvet scoter (non-breeding) representation in Scottish population in GB is of Low importance to the wintering population of this regularly occurring migratory

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SPA network. species in Europe. The European population status is considered Vulnerable, and therefore measures to improve their conservation status are considered to be of high importance.

Accordingly, the overall assessment of the relative value of protected areas in Scotland’s marine environment to conservation of velvet scoter (non-breeding) in Europe is High.

This assessment indicates there is an expectation of velvet scoter (non-breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience.

Table 2 Vulnerability of velvet scoter (non-breeding) populations to anthropogenic threats and pressures.

Vulnerability to There is evidence of activities that may take place in UK waters generating pressures or threats likely to have threats and medium impacts on relevant populations of velvet scoter (non-breeding) (Furness, 2016) including chronic oil pressures pollution and spills and accidental bycatch/drowning in fishing nets (Mendel et al, 2008; ICES, 2013). Empirical data on bycatch in British waters are lacking, but velvet scoter are identified as among the most sensitive species for bycatch at depth near the seabed, with some areas of relatively high potential vulnerability in the winter months encompassing areas with high common scoter densities along North Sea coasts (Bradbury et al, 2017).

Velvet scoter are sensitive to visual disturbance associated with vessel movements (Mendel et al, 2008; Cook & Burton, 2010; Schwemmer et al, 2011) and displacement and barrier effects have been documented at offshore wind farms (Dierschke & Garthe, 2006). However, the extent and significance of any population level impacts arising from disturbance and displacement, including during the flightless moult period, is unknown.

Velvet scoter (non-breeding) populations are vulnerable to impacts of climate change (Hartman et al, 2013). Well- managed protected sites are important to promoting the resilience of species and habitats to the impacts of climate change with larger areas of habitats and species’ populations providing better opportunities for sustaining diversity (SNH, 2016). Marine pSPAs can also contribute to adaptation to climate change by reducing other pressures, reducing fragmentation and safeguarding supporting habitats (SNH, 2016).

Velvet scoter populations are vulnerable to medium impacts from to a number of different threats and pressures. Replication within OSPAR regions is recommended.

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3. Contribution to Scottish SPA network

This section considers the occurrence of velvet scoter (non-breeding) within the marine proposed SPAs and existing SPAs in Scotland. Velvet scoter (non-breeding) are being considered for inclusion at three marine proposed SPAs and are represented in two existing estuarine/coastal SPAs.

Table 3 Summary of occurrence of velvet scoter (non-breeding) within marine proposed SPAs in the Scottish MPA network

Proposed SPAs Representation Replication Geographic range Linkages

North Orkney Supports up to c. Velvet scoter (non- Provides the only example No known linkages 5.9% of the GB non- breeding) is in the Northern Isles and breeding population. represented within 3 represents the northern proposed SPAs and 3 extent of the range of this existing species in Scotland. Moray Firth Supports up to c. coastal/estuarine SPAs. Provides an example on No known linkages 59.5% of the GB the east mainland coast non-breeding Replication of this and represents the core population. feature in the network is part of the range of this proposed in OSPAR species in Scotland. Outer Firth of Supports a non- Region II. No sites Provides an example on Velvet scoter is a feature of the non- Forth & St breeding waterfowl were identified in the east mainland coast breeding waterbird assemblage of the Andrews Bay assemblage, OSPAR Region III and represents the Firth of Forth SPA and Firth of Tay Complex including velvet southern extent of the and Eden Estuary SPA, both of which scoter equivalent to range of this species in are contiguous with this marine up to c. 23.2% of the Scotland. proposed SPA. The velvet scoter GB non-breeding population in this area will use both population. (intertidal) estuarine and (sub-tidal) marine environments.

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4. Summary

The species assessment (Table 1) indicates there is an expectation of velvet scoter (non- breeding) being represented at least twice in each OSPAR region overlapping its Scottish distribution, ensuring full geographic coverage of the species’ range in Scotland; replication of representation in regions is considered necessary to enhance species’ resilience. The Scottish SPA network includes three marine proposed SPAs for velvet scoter (non- breeding) and three existing estuarine/coastal SPAs. The marine proposed SPAs support up to 88.6% of the GB non-breeding population with all proposed SPAs in OSPAR Region II (Northern Isles and east coast). The locations of the proposed SPAs reflect the full geographic range and variation of velvet scoter (non-breeding) in Scotland; large aggregations are confined to North Sea coasts.

The number and distribution of proposed marine SPAs for velvet scoter (non-breeding) in the Scottish pSPA network, as summarised above and in Table 3, is consistent with the species assessment (Table 1) but exceeds the minimum level of representation.

Replication in OSPAR Region II is considered appropriate because there is evidence that velvet scoter (non-breeding) populations may be vulnerable to a number of threats and pressures associated with activities in the marine environment. Site-based protection of areas used regularly by large aggregations is considered an appropriate conservation measure to enhance resilience of velvet scoter (non-breeding) to such threats and pressures.

Inclusion of velvet scoter (non-breeding) in the Outer Firth of Forth and St Andrews Bay Complex pSPA provides added conservation value to the Scottish marine SPA network as it is contiguous with an existing estuarine SPA and together they capture the full range of intertidal and subtidal habitats used by non-breeding velvet scoter at this location.

5. Conclusion

The number and distribution of marine proposed SPAs for velvet scoter (non-breeding) is fully justified based on the relative value of protected areas in Scotland’s marine environment to the conservation of velvet scoter (non-breeding) in Europe.

The case for inclusion of velvet scoter (non-breeding) in the Outer Firth of Forth and St Andrews Bay Complex pSPA is further supported because it is functionally linked to an existing SPA.

No further SPA provision is considered necessary for velvet scoter (non-breeding).

6. References

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