Aquatic Survey and Monitoring Ltd.
Tí Cara, Point Lane, Cosheston, Pembrokeshire, SA72 4UN, UK Tel office +44 (0) 1646 687946 Mobile 07879 497004 E-mail: [email protected]
Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015
A report for SOTEAG
Prepared by: Jon Moore & Christine Howson
Status: Final Date of Release: 1st December 2015
Recommended citation: Moore, J.J. and Howson, C.M. (2015). Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015. A report to SOTEAG from Aquatic Survey & Monitoring Ltd., Cosheston, Pembrokeshire. 33 pp + iii.
Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015 Page i
Acknowledgements Surveyors: Jon Moore, ASML, Cosheston, Pembrokeshire Christine Howson, ASML, Ormiston, East Lothian
Other assistance and advice: Mr Alex Thomson and colleagues at BP Pollution Response Base, Sella Ness; Mr Simon Skinner, Port Safety Officer, Ports and Harbour Department, Sella Ness
Report review: Christine Howson, ASML, Ormiston, East Lothian Dr Mike Burrows and other members of the SOTEAG monitoring committee
Data access This report and the data herein are the property of the Sullom Voe Association (SVA) Ltd. and its agent the Shetland Oil Terminal Environmental Advisory Group (SOTEAG) and are not to be cited without the written agreement of SOTEAG. SOTEAG/SVA Ltd. will not be held liable for any losses incurred by any third party arising from their use of these data. © SOTEAG/SVA Ltd. 2015
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Summary The potential environmental impacts of operations at the Sullom Voe oil terminal were recognised when construction of the complex began in 1975. A monitoring programme was devised by the Shetland Oil Terminal Environmental Advisory Group (SOTEAG). The rocky shore element of this monitoring programme began in 1976 and, apart from a break of two years (1982-83), the rocky shores in Sullom Voe have been surveyed annually. It is thought to be the longest running continuous programme of rocky shores surveys anywhere in the world. The programme was designed to assess gross changes in the plant and animal populations and the survey sites are centred on the oil terminal. Annual reports to SOTEAG have described the changes from year to year and assessed the effects of the terminal operation. This report summarises the work carried out in July 2015 – the 38th survey since the programme’s inception. The work was carried out using exactly the same methodology as that used since 1993. The surveys were carried out during a period of spring tides. The fifteen original transects in Sullom Voe and the five reference transects outside the Voe were re-surveyed, and the abundance of conspicuous species was recorded at five stations along each transect. A photographic record of each site was made. Comparisons of recorded abundances, field notes and photographs from the 2015 survey with those from the 2014 survey and previous surveys have been carried out. Rocky shore communities at the twenty sites in 2015 were generally very similar to 2014. The most notable features are listed below: Small numbers of the southern barnacle Chthamalus stellatus were recorded from three sites and small populations of the southern limpet Patella ulyssiponensis were recorded from two sites. Records of these species are still fairly new to this monitoring programme. Barnacle abundances remained high and observations suggest that survival of adults from the previous year was particularly high. Small populations of the immigrant barnacle Austrominius modestus still persist at sites within the inner Voe. Abundances of juvenile limpets were particularly high, almost reaching the peak recorded in 1997. The population of dogwhelks between the terminal jetties was still very small. Reduced densities were recorded from a number of sites. As discussed in previous reports, densities of rough periwinkles and flat periwinkles have remained relatively very low since 2000, while abundances of serrated wrack and bladder wrack have notably increased over the course of the monitoring programme. As also discussed in previous reports, the long term recovery of knotted wrack, Ascophyllum nodosum, at four sheltered sites in Sullom Voe, following various impacts in the 1970s, has been described and updated. Most of the changes summarised above are considered to be due to natural fluctuations, with the exception of the knotted wrack recovery. There was one reported oil spill (20 litres of marine diesel) in Sella Ness harbour in the period between the July 2014 and July 2015 surveys, with no observed impacts on the rocky shore communities. A containment bund between Jetties 1 and 2, following a seepage of oily waste from the terminal in 2012, is still in place, but remediation is planned. Analysis of the community data from the nearby rocky shore monitoring site still showed no apparent effects from the seepage or bund. Rocky shore communities around the Voe appeared to be in good condition and there were no detected effects of terminal activities at the transect sites.
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Contents Acknowledgements ...... i Data access ...... i Summary ...... ii Contents ...... iii 1 Introduction ...... 1 2 Methods ...... 1 2.1 Field survey ...... 1 2.1.1 Site and station location ...... 1 2.1.2 In situ species recording...... 3 2.1.3 Photography ...... 3 2.2 Data analysis ...... 3 3 Results ...... 7 3.1 Fluctuations in abundance of species ...... 7 3.1.1 Hydroids ...... 8 3.1.2 Chthamalus stellatus ...... 9 3.1.3 Semibalanus balanoides ...... 10 3.1.4 Austrominius modestus ...... 12 3.1.5 Small limpets & chitons ...... 13 3.1.6 Patella vulgata ...... 14 3.1.7 Patella ulyssiponensis ...... 15 3.1.8 Littorina littorea ...... 15 3.1.9 Littorina obtusata & L. mariae ...... 17 3.1.10 Littorina saxatilis and Littorina saxatilis (ecotype neglecta) ...... 18 3.1.11 Nucella lapillus ...... 20 3.1.12 Flustrellidra hispida & Alcyonidium spp...... 22 3.1.13 Red algal turf species ...... 22 3.1.14 Laminaria digitata ...... 25 3.1.15 Ascophyllum nodosum ...... 26 3.1.16 Fucus serratus ...... 27 3.1.17 Fucus vesiculosus ...... 28 3.1.18 Green algae ...... 29 3.2 Site-specific descriptions ...... 30 3.2.1 Orka Voe bund ...... 30 4 Discussion ...... 30 4.1 Effects of terminal operations and oil spills...... 30 5 References ...... 31 Appendix 1 Abundance scales used for intertidal organisms ...... 32 Appendix 2 Chronology of personnel changes and methodology during SOTEAG rocky shore monitoring programme ...... 33
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1 Introduction Biological monitoring of rocky shore communities in Sullom Voe has been carried out annually since 1976, with only one break in survey between 1982 and 1983. Between 1976 and 1981 ‘full’ surveys were carried out in all stations at between 23 and 43 sites, with surveyors recording onto blank recording forms – i.e. with no reference to previous results. Between 1984 and 1992, following a review of the programme (Hiscock 1983), the methodology was changed and the survey took the form of a rapid visual assessment of the shores to identify gross changes. This involved: comparing, in the field, abundances of species along the fixed transects with records from the most recent full survey (1981, 1987 or 1988), viewing longer sections of the shores from the sea or by walking; and comparing photographs taken from defined viewpoints with those taken in previous years. In 1993, following suggestions from the SOTEAG monitoring committee, the methodology was modified to allow more detailed and objective analysis of the data. The number of survey sites in Sullom Voe was reduced and five reference sites were established outside the Voe. Comprehensive surveys, rather than rapid visual assessment surveys, were carried out at five stations along each transect, representing the main zones. The latter methodology has been used annually since 1993 and this report describes the results of the survey in July 2015, highlighting changes that occurred since the survey in 2012 and discussing any notable longer term fluctuations or trends. The various changes in sites and transect stations surveyed, survey month and survey personnel that have occurred over the 38 years of the SOTEAG rocky shore monitoring programme are summarised in Appendix 2. Moore (2013) provides a more detailed summary of the whole rocky shore transect monitoring programme (1976 to 2012), including a description of the methodology, the methodological changes that have occurred during the course of the programme, the database and the limitations of the data. Note: An associated programme of surveys of dogwhelk populations at rocky shore sites around Sullom Voe and Yell Sound is carried out approximately every two years, and was carried out during the July 2015 survey (Moore and Gubbins, 2015). Appendix 2 lists the dogwhelk survey years.
2 Methods
2.1 Field survey Fieldwork was carried out by Jon Moore and Christine Howson between the 13th and 22nd July 2015. Table 1 details the sites and the transect stations surveyed, and Figures 1 and 2 show the location of the sites. Surveys were carried out within three hours of low water.
2.1.1 Site and station location Fifteen sites are located within, or at the entrance to, Sullom Voe to enable monitoring of the effects of oil terminal activities. A further five sites are located in Vidlin Voe and Burra Voe to act as reference sites for the natural changes that occur in rocky shore populations. Access to sites was either by car and foot, or by boat as appropriate. A workboat was supplied by the BP Pollution Response Base. A hand held GPS receiver and site location sheets, containing maps, colour photographs and written notes in laminated plastic, were used to aid relocation. The site numbering system is based on the wave exposure of the shore. The first number (ranging from 1 to 6) is based on the Ballantine scale (Ballantine, 1961), which uses the biological communities on the shore to estimate the wave exposure (where 1 = extremely exposed). The second number is a consecutive number at that exposure.
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A fixed datum marker, usually a pat of concrete and/or a paint mark, marks the top of each transect. The line of the transect is defined by a bearing and by reference to conspicuous marks (permanent rock features and distant landmarks) shown in the photographs on the site location sheet. A tape may be laid down the shore from the fixed datum marker at the top of the transect, to provide a visible reference. Fixed recording stations have been established along the transects at all sites. The stations are located at 20 cm height intervals from the fixed datum marker. These stations are marked with paint, where possible in the upper shore zones, or relocated by use of a cross staff level (with a 20 cm shaft) and the tape measurements. On the shores with extensive plateaux or very gradual slopes, the tape measurements alone are usually reliable. Relocation has been improved since 1993 by using annotated photographs of transects and close-up photographs of the stations. In most cases these now allow more rapid and precise relocation of the stations. The number of stations on the transect varies from twenty nine stations at West of Mioness (site 1.1) where there is an extensive supralittoral lichen zone, to ten at Scatsta Ness (sites 6.12 and 6.13). Table 1 Rocky shore transect sites surveyed in Sullom Voe in July 2015, with the stations surveyed on each transect. A station number with a strikethrough indicates that it was not surveyed, while brackets indicate that the survey may have been incomplete (see text for explanation). No. Site name Stations surveyed Survey date Monitoring sites 1.1 W. of Mioness 15, 18, 21, 24, 27 14/07/2015 2.3 Roe Clett 8, 11, 14, 17, 20 16/07/2015 3.3 Noust of Burraland 1, 3, 5, 7, 10 15/07/2015 3.4 Gluss Island East 6, 9, 11, 13, 15 14/07/2015 3.5 S. of Swarta Taing 4, 7, 10, 12, 15 15/07/2015 4.1 Grunn Taing 3, 5, 7, 9, 11 14/07/2015 4.3 The Kames 5, 7, 9, 12, 15 16/07/2015 4.6 Voxter Ness 5, 8, 10, 12, 14 21/07/2015 5.1 S. of Skaw Taing 9, 12, 15, 18, 20 16/07/2015 5.2 Jetty 3 5, 7, 9, 11, 13 18/07/2015 5.5 Mavis Grind 3, 5, 7, 9, 12, 14 17/07/2015 6.1 Fugla Ayre 3, 5, 7, 9, 11 15/07/2015 6.2 S. of Jetty 2 3, 6, 9, 11, 13 18/07/2015 6.12 Scatsta Ness (cleared) 2, 4, 6, 7, 8 17/07/2015 6.13 Scatsta Ness (uncleared) 4, 5, 8, 10, 12 17/07/2015 Orka Voe bund n/a Reference sites 2.9 Riven Noust 13, 17, 19, 22, 24 17/07/2015 3.8 Vidlin Ness 5, 7, 9, 10, (12) 20/07/2015 3.12 Burgo Taing 3, 6, 9, 11, 13 18/07/2015 6.11 Kirkabister 4, 6, 8, 10, 12 20/07/2015 6.14 N. Burra Voe 4, 6, 8, 10, 12 18/07/2015 Five stations are now monitored on each transect, selected to represent the five major shore zones of lower shore (LS), lower middle shore (LMS), middle shore (MS), upper middle shore (UMS) and upper shore (US) as defined by their relative height above chart datum and their assemblages of plants and animals. Unfortunately, a poor low tide (and low pressure) during the survey of Transects 3.8 and 6.11 (Vidlin Ness and Kirkabister) in 2015 survey made the lower shore station at Kirkabister inaccessible and the lower shore station at Vidlin Ness may not have been thorough. At two sites (Mavis Grind and Voxter Ness), it has normally also been possible to survey an additional station in
Aquatic Survey & Monitoring Ltd. December 2015 Survey of the rocky shores in the region of Sullom Voe, Shetland, July 2015 Page 3 the sublittoral fringe (SLF), but tides and time did not allow for this during the 2015 survey. The stations surveyed are listed in Table 1.
2.1.2 In situ species recording Comprehensive surveys were made of all conspicuous species at each selected station. The abundances of conspicuous animals, algae and lichens were noted and recorded from a 3 m horizontal strip (1.5 m each side from the relocated station mark). The width of the strip varies depending on the slope of the substrata, aiming to represent the 10 cm height band lying below the relocated station mark. On vertical rock surfaces the band is therefore 10 cm high, but a broader band, to a maximum of 30 cm, is surveyed on gradually sloping areas. Precise relocation can be difficult over the full 3 m length, but can be improved with the aid of a 3 m length of leaded line laid along the top of the station. Records were written into a standard pro-forma on waterproof paper, with checklists of species for animals and plants. The surveyors also carried a copy of the abundance scales. The abundance scales used are those described in Baker and Wolff (1987) (Appendix 1), which have been used since the inception of the programme in 1976. Any points of interest on the shores or relating to the populations observed were noted in the field.
2.1.3 Photography Photographs were taken of each transect from different viewpoints and angles, usually the same as on the site location sheet, and close-ups of selected stations. The equipment used was a Ricoh WG-4 digital compact camera for most sites and a Sonim Ex-Handy 07 intrinsically safe mobile phone for the two Jetty sites. Digital images (high resolution jpgs) were recorded and copies are filed with SOTEAG and ASML.
2.2 Data analysis The data from the survey were entered into a computer spreadsheet (Microsoft Excel). They were then transferred to a more versatile database package (Microsoft Access version 2013) that held the data from previous surveys, for further analysis. Each record comprises the species name and taxonomic code (based on Howson & Picton, 1997), the site number, the year and the recorded abundance at each station. The abundances are recorded as the numerical equivalent of the categories, e.g. 4 = Common (see Appendix 1). All taxonomic nomenclature used in the database and this report has been revised and updated according to the World Register of Marine Species (www.marinespecies.org). Tabulated printouts from the database, simple graphical presentations (histograms in section 3.1) and non parametric statistics (Wilcoxon signed rank test) were used to compare the 2015 species abundances with previous years. In addition, the field notes and the photographs were compared with those from previous years and any notable changes described. Because each abundance value is based on a semi-quantitative category, the numbers should not be summed or averaged. However, a method has been devised to calculate mean abundances from these values and plot them as histograms. The histograms have been produced from the 1984 to 2015 data for the 15 monitoring sites, by calculating the mean abundance of species or groups of species within each survey. The following methodology was used to calculate mean abundance for a species from the semi- quantitative data: 1. The maximum number of monitoring stations in which each species had been recorded was calculated from the 1993 to 2015 database (For example: Semibalanus balanoides had been recorded from a maximum of 57 stations, out of the 75 stations that are annually monitored);
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2. The relevant abundance scale was chosen for the species; 3. Using that scale, the log of the median value of abundance within a category (Table 2) was multiplied by the number of records of that abundance category within the chosen station’s dataset; 4. The resulting products from each abundance category were added together; 5. This figure was then divided by the number of stations calculated in 1 (above) and anti- logged. The result is the mean abundance over the normal range of the species, in the units given in column 2 of Table 2.
Table 2 Median values used in calculations for each abundance category
Abundance category Scale Units R O F C A S Ex 1 No./0.01m2 0.005 0.5 5 50 200 400 600 2 No./0.01m2 0.005 0.05 0.5 5 55 200 350 3 No./0.1m2 0.05 0.25 0.75 2.5 7.5 15 30 4 No./0.1m2 0.05 0.5 2.5 7.5 15 35 60 5 No./1m2 0.25 0.5 2.5 7.5 25 75 130 6 % cover 0.1 1 2.5 12 35 65 90 7 No./0.01m2 0.005 0.05 0.5 25 60 - - 8 No./0.01m2 0.005 0.05 0.5 50 150 - - 9 % cover 0.1 1 2.5 12 25 - - 10 % cover 0.1 0.5 2.5 10 35 65 90 11 % cover 0.2 1 2.5 17 45 75 95
Whilst it should be appreciated that this methodology will introduce some errors into the data, the transformation of the densities will reduce the scale of this inaccuracy by taking better account of shifts at both ends of the abundance scale. The histograms are a useful means of graphically presenting trends that have been identified by a detailed scrutiny of the data. For some groups of taxa, including epiphytic bryozoa on fucoid algae and red algal turf species, the abundance data can also be summed and graphed to look for any trends across those whole groups. The method for summing those abundance data across taxa has been improved since the 2014 report. In addition to the average abundance histograms plotted from the above analysis, the graphs also include line plots of the number of stations from which the species was recorded. The values are given on a second y-axis (on the right of the graph). The maximum number of monitoring stations is 75 (15 sites x 5 stations). The maximum number of reference stations is 25 (5 sites x 5 stations), so the combined maximum is 100 stations.
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Figure 1 Location of rocky shore transect monitoring and reference sites. Surveys of rocky shores in the region of Sullom Voe, Shetland, July 2015.
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Figure 2 Location of rocky shore transect monitoring sites within Sullom Voe. Surveys of rocky shores in the region of Sullom Voe, Shetland, July 2015.
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3 Results
3.1 Fluctuations in abundance of species Table 3 provides a summary of the abundance changes that occurred between July 2014 and July 2015 for species recorded. The majority of these changes continued to reflect a low level of natural variability from year to year, but there were notable changes in some species and at some sites. Species emboldened are discussed later in this section. Table 3 Summary of the main changes in selected species presence/absence and abundance between 2014 and 2015 over all sites and stations (including reference sites). Values are the No. of stations out of 100 (20 sites x 5 stations). See category definitions at bottom of table. Species names in bold indicate those which are discussed in the sections below. Distribution is the known biogeographic distribution relative to Britain (see Section 4.2). Taxa Distribution None Gone Down Same Up New Halichondria panicea Ubiquitous 84 0 0 14 0 2 Clava Ubiquitous 90 2 0 0 1 7 Dynamena pumila Ubiquitous 85 2 0 7 0 6 Actinia equina Ubiquitous 84 7 0 7 0 2 Spirobranchus Ubiquitous 91 4 0 4 0 1 Spirorbinae Ubiquitous 73 6 0 20 0 1 Cirripedia (spat) Ubiquitous 23 8 11 53 3 2 Cirripedia (dead) Ubiquitous 27 8 2 57 0 6 Semibalanus balanoides Northern 22 1 2 72 1 2 Amphipoda Ubiquitous 77 7 2 8 0 6 Carcinus maenas Ubiquitous 87 7 0 3 0 3 Patella (juvenile, <10mm) Ubiquitous 57 3 1 23 2 14 Patella vulgata Northern 27 5 2 58 6 2 Littorina littorea Northern 61 9 3 21 0 6 Littorina obtusata Ubiquitous 61 8 2 22 3 4 Littorina saxatilis (ecotype neglecta) Southern 57 7 2 29 1 4 Littorina saxatilis Northern 38 11 5 39 2 5 Nucella lapillus Northern 57 15 2 17 1 8 Mytilus edulis Ubiquitous 63 2 0 30 0 5 Alcyonidium hirsutum Ubiquitous 91 4 0 4 0 1 Flustrellidra hispida Ubiquitous 86 3 0 11 0 0 Electra pilosa Ubiquitous 86 3 0 4 0 7 Rhodophyta (encrusting) Ubiquitous 79 8 2 8 0 3 Porphyra Ubiquitous 73 8 2 8 1 8 Dumontia contorta Ubiquitous 83 4 1 3 0 9 Hildenbrandia Ubiquitous 40 16 5 22 3 14 Corallinaceae (encrusting) Ubiquitous 48 7 4 27 6 8 Corallina Ubiquitous 84 5 0 9 0 2 Mastocarpus stellatus Northern 70 4 3 13 1 9 Chondrus crispus Northern 78 8 1 8 0 5 Lomentaria articulata Ubiquitous 88 3 2 5 1 1 Ceramium shuttleworthianum Ubiquitous 75 11 2 7 0 5 Membranoptera alata Ubiquitous 89 0 0 5 2 4 Osmundea hybrida Southern 90 5 0 2 0 3 Osmundea pinnatifida Southern 82 5 2 8 0 3 Vertebrata lanosa Ubiquitous 81 1 0 10 1 7 Ectocarpaceae Ubiquitous 92 4 0 0 0 4
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Elachista fucicola Ubiquitous 67 11 1 11 0 10 Leathesia marina Ubiquitous 90 4 2 0 0 4 Laminaria digitata Northern 92 2 0 4 0 2 Ascophyllum nodosum Northern 84 1 0 12 0 3 Fucus serratus Northern 72 3 2 20 0 3 Fucus spiralis Northern 79 2 2 10 1 6 Fucus vesiculosus Northern 53 4 5 32 2 4 Pelvetia canaliculata Northern 75 2 2 17 0 4 Ulva (tubular) Ubiquitous 54 9 3 21 2 11 Ulva (flat) Ubiquitous 80 6 3 6 0 5 Cladophora Ubiquitous 61 23 1 10 0 5 Cladophora rupestris Ubiquitous 72 0 0 0 0 28 Caloplaca marina Ubiquitous 89 1 0 9 0 1 Verrucaria maura Ubiquitous 13 8 6 57 3 13 Verrucaria mucosa Ubiquitous 70 10 2 5 0 13 None = not recorded at the station in 2014 or 2015 Gone = recorded at the station in 2014, but not in 2015 Down = decreased abundance in 2015 Same = same or almost same (up or down by only one class) in 2014 and 2015 Up = increased abundance in 2015 New = recorded at station in 2015 but not in 2014 The following sections describe the results for selected species that have shown notable changes. The histograms have been prepared using the methodology described in Section 2.2. The dot tables provide examples from the database of abundances to illustrate the changes (or lack of change) described in the text. The number and size of the dots represent the recorded abundances: = Rare; = Occasional; = Frequent; = Common; = Abundant; = Super abundant; = Extremely abundant; - = not found; ns = no survey. Please refer to Appendix 1 for explanation of the abundance categories used for each species. The shore zones listed in the left column of the dot tables are identified as follows: upper shore (US), upper middle shore (UMS), middle shore (MS), lower middle shore (LMS), lower shore (LS) and sublittoral fringe (SLF). Note: for readers with the electronic version of this report, the species names in the section headings below contain hyperlinks to relevant pages on their biology on the MarLIN website.
3.1.1 Hydroids A few species of thecate and athecate hydroids are present in sheltered habitats, mainly on the lower shore. Thecate species include Dynamea pumila, which often colonises Fucus serratus, and various members of the Campanulariidae (in this survey often recorded simply as Obelia), small specimens of which are often found in very sheltered niches at the base of algal turfs or between stones. Athecate species include Clava multicornis, which often colonises Ascophyllum nodosum and other fucoid algae. However, for most species and the majority of sites their presence is limited to scattered colonies in low abundance. The graph below therefore shows the number of records, rather than abundances, of the three species most often recorded. They are included in this results section as examples of some of the considerable variety of species present in low abundance, and because it was noticed that numbers of records of Clava multicornis have increased over the last 4 years. Recording of this cryptic species is not always thoroughly reliable, but the trend may be interesting. Prior to 1993 this species was not included on the species checklist or routinely recorded, so records are very sparse.
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South of Swarta Taing (site 3.5) – Colony of Clava multicornis (centre, pink) amongst turf of algae (Himanthalia and Mastocarpus), sponge (Halichondria) and bryozoan (Flustrellidra).
Monitoring site no. 3.5 S.of Swarta Taing Clava multicornis Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 LS - - - ------ -
3.1.2 Chthamalus stellatus This southern species of barnacle, first recorded from the transect sites in 2011, was again found in very small numbers at three sites in 2015 – West of Mioness (1.1) and the reference sites Riven Noust (2.9) and Burgo Taing (3.12).
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West of Mioness (site 1.1) – single Chthamalus stellatus, with black Verrucaria (lichen) and juvenile Semibalanus balanoides, July 2015.
3.1.3 Semibalanus balanoides Barnacle spat were not quite as abundant in 2015 as 2014, but were still present in high abundances at many sites and the average abundances over all sites was still higher than previous surveys. This is exaggerated by the histogram below, which is strongly influenced by the records of extremely abundant and super abundant spat at a few stations.
Again, the high densities of spat had no obvious effects on the recorded abundances of adult barnacles which were very similar to 2013 and 2014 in almost all stations. The pattern of survival and recruitment was also similar to 2014, with notably high survival of adult barnacles from the previous year and relatively limited recruitment of the 2015 settlement.
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Gluss Island East (site 3.4) – large old Semibalanus balanoides amongst smaller recruits that settled in 2015.
Monitoring site no. 3.4 Gluss Island East Semibalanus balanoides Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS MS
LMS
LS
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Reference site no. 3.12 Burgo Taing Semibalanus balanoides Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 US
UMS
MS LMS - LS -
3.1.4 Austrominius modestus Small populations of this immigrant barnacle still persist at sites within the inner Voe and in 2015 they were recorded from three stations (5, 7 and 9) at Mavis Grind (5.5) as well as the usual records from Voxter Ness (4.6).
Mavis Grind (site 5.5) – Austrominius modestus (top) and Semibalanus balanoides (bottom), July 2015.
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3.1.5 Small limpets & chitons The graph below shows fluctuations in numbers of records of three small molluscs with some similarities in their form and life style. Polyplacophora (chitons), Testudinalia testudinalis (common tortoiseshell limpet) and Tectura virginea (white tortoiseshell limpet) are all small flattened mobile grazers of surface microalgae on bedrock and boulders, mainly within the shallow subtidal. Small numbers are recorded from the lower shore of various sites, but the graph shows that there have been fewer records in the last decade compared to the previous decade.
Scatsta Ness (cleared) (site 6.12) – Tortoiseshell limpet, Testudinalia testudinalis, on a lower shore boulder, July 2015.
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3.1.6 Patella vulgata Populations of adult limpets remained very stable at all sites, with only small fluctuations in abundance at some stations. Abundances of juvenile limpets, however, showed a notable increase, with an average abundance that almost reached the peak recorded in 1997. This increase in the average abundance was mainly due to small increases at many sites and stations, but there were larger increases in a few stations.
Monitoring site no. 1.1 S.of West of Mioness Patella vulgata Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 US ------ - - - - - - - UMS
MS
LMS
LS
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Monitoring site no. 5.1 S.of Skaw Taing Patella (juvenile, <10mm) Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 MS - - ------ LMS - - - - - - - - LS - - - - - - - - - -
Reference site no. 2.9 Riven Noust Patella (juvenile, <10mm) Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 MS - - - - - - ------ LMS LS -
3.1.7 Patella ulyssiponensis Populations of this southern species of limpet are concentrated in upper shore rock pools at wave exposed sites, but these pools do not lie within the monitored stations. However, small populations are found in the lower shore stations at some sites, but distinguishing them in-situ from P. vulgata is difficult and their presence in some stations has only been confirmed in recent years. In 2015 small numbers were found to be present at W.of Mioness (site 1.1) and Riven Noust (site 2.9). The population at the latter is a new record for the site. Future monitoring should be able to detect notable increases in the lower shore populations, but may not reliably detect declines.
3.1.8 Littorina littorea Notable populations of edible winkles are most often found in midshore stations with abundant fucoid algae and lots of cavities, particularly the boulder shores. These habitats do not change markedly from year to year, but the abundance of L. littorea can fluctuate considerably, especially at certain sites and tidal heights on the edge of their distribution. Thus, while the graph below suggests a decline in abundances over the last few years, this is not expressed in the stations where these snails are typically most abundant. However, the examples given below show the sorts of fluctuations that can occur at individual stations.
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Monitoring site no. 6.12 Scatsta Ness (cleared) Littorina littorea Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
UMS - - - MS
LMS LS - - - - - -
Monitoring site no. 6.2 South of Jetty 2 Littorina littorea Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS - - - - - - - - -
MS LMS
LS - The table below provides another way of summarising the fluctuations on a site level. It crudely highlights the influence of wave exposure (indicated by the first digit of the site code in the first column) and the scale of abundance fluctuations. Some years do stand out as having particularly high or low numbers, and observations made during those surveys suggest that these are characterised by particularly successful recruitment of juveniles or poor survival of adults respectfully.
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Littorina littorea (sum of abundance scores from five stations, by site and year) Site Site name 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 1.1 W.of Mioness 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 2.3 Roe Clett 0 0 0 0 0 0 0 0 0 0 0 0 0 2 2 0 0 0 0 2 0 2 0 2.9 Riven Noust 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 3.3 Noust of Burraland 2 3 0 0 12 0 0 0 0 0 0 0 0 1 2 0 0 0 0 0 0 2 2 3.4 Gluss Island East 3 5 4 5 5 4 3 5 5 0 2 6 5 7 7 7 4 7 7 6 6 5 3 3.5 S.of Swarta Taing 0 0 0 0 0 0 0 0 0 0 0 0 0 2 0 0 1 3 0 4 0 2 0 3.8 Vidlin Ness 7 0 0 0 2 0 0 2 0 0 0 0 2 2 0 0 2 6 7 2 0 2 7 3.12 Burgo Taing 0 0 0 0 0 0 3 0 0 0 0 0 0 0 0 0 0 0 2 0 0 0 0 4.1 Grunn Taing 2 2 4 2 0 6 4 5 2 2 5 6 4 6 8 1 2 4 7 8 0 6 2 4.3 The Kames 2 0 2 3 4 0 6 0 3 0 8 3 6 2 7 2 4 3 5 3 3 2 3 4.6 Voxter Ness 17 11 7 9 9 11 11 16 12 10 12 13 18 13 13 11 9 10 2 10 10 8 6 5.1 S.of Skaw Taing 5 9 6 4 5 6 4 4 5 4 6 7 6 9 5 4 5 8 5 8 6 5 7 5.2 Jetty 3 11 11 12 12 8 12 13 7 11 14 12 16 11 13 13 11 11 14 14 11 14 11 15 5.5 Mavis Grind 9 9 2 6 5 7 11 14 11 8 17 13 10 12 11 11 13 5 8 4 2 3 6 6.1 Fugla Ayre 7 5 2 0 2 0 4 3 7 5 7 5 3 0 0 0 3 3 3 3 7 2 0 6.2 S.of Jetty 2 7 14 11 13 14 14 17 16 15 12 18 15 18 13 15 8 20 18 17 19 23 21 14 6.11 Kirkabister 6 10 9 7 7 10 10 10 11 15 12 16 11 8 11 11 15 18 19 18 14 14 7 6.12 Scatsta Ness (cleared) 14 11 16 14 16 14 16 15 18 13 18 17 13 17 16 11 16 16 18 21 16 16 19 6.13 Scatsta Ness (uncleared) 12 9 12 8 12 11 14 16 12 13 8 14 14 14 14 14 16 15 19 19 19 19 18 6.14 N.Burra Voe 0 6 2 3 5 2 8 3 6 6 3 6 2 3 5 4 4 3 2 2 0 3 3
3.1.9 Littorina obtusata & L. mariae Flat winkles, which are not differentiated into the two species in this survey, have a similar distribution to L. littorea, but are more reliant on fucoid algae. Recorded abundances have been generally lower in recent years than they were during the 1980s and 1990s and the abundances in 2015 were fairly typical of recent years.
The correlation between the abundances of L. obtusata and fucoid algae is illustrated by the data from Vidlin Ness (see tables below). Between 1998 and 2008 the site was characterised by relatively low cover of Fucus vesiculosus and low abundances of flat winkles. F. vesiculosus then increased and provided a better habitat for the winkles.
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Monitoring site no. 3.8 Vidlin Ness Littorina obtusata Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS ------ - - - MS ------ LMS ------ LS -
Monitoring site no. 3.8 Vidlin Ness Fucus vesiculosus Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS ------ -
MS - - - - LMS - - - LS ------ - -
3.1.10 Littorina saxatilis and Littorina saxatilis (ecotype neglecta) The rough periwinkles include a number of recognised species and subspecies that have been recorded from Shetland. However, in-situ identification is often difficult, particularly with juveniles, and this survey programme categorises them into just two entities: Littorina saxatilis – mainly concentrated in upper shore rocky habitats, particularly in crevices and under stones on upper shore shingle Littorina saxatilis (ecotype neglecta) - living amongst barnacles and within dead barnacle cases on rocky shores that are exposed or moderately exposed to wave action
Mavis Grind (site 5.5) – Barnacles (Semibalanus balanoides), and rough periwinkles (Littorina saxatilis (bottom) and Littorina saxatilis ecotype neglecta (in dead barnacle shell)), July 2015.
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Recording abundance of these snails has potential for considerable inconsistency, particularly for L. saxatilis in crevices or under stones on warm dry days (when they hide away) rather than wet days (when they come out to feed). This probably explains some of the large fluctuations shown in the graphs and examples below and is why they have not often been discussed in the annual reports. However, real fluctuations in their populations are also likely. The graphs also show that recorded abundances of both species were much higher during the 1980s and early 1990s than they have been over the last two decades. This has been discussed in previous reports, but no explanation has yet been found. The survey methodology has not changed. There have been no notable trends or changes in recent years, but it was considered appropriate to give an update.
Monitoring site no. 3.3 Noust of Burraland Littorina saxatilis Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 US - - UMS - MS - - - - - - - - - LMS - ------
Reference site no. 6.11 Kirkabister Littorina saxatilis Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
US -
UMS
MS - LMS - - - -
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Monitoring site no. 3.3 Noust of Burraland Littorina saxatilis (ecotype neglecta) Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS - - - - - - - MS LMS LS ------
Reference site no. 2.3 Riven Noust Littorina saxatilis (ecotype neglecta) Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS MS LMS LS - - - ------
3.1.11 Nucella lapillus A gradual recovery of dogwhelk populations has been described in recent years from sites close to the oil terminal. Signs of this recovery process were less obvious in 2015, though many juveniles were present on The Kames (4.3) transect site. The population between the jetties was still very small and none were recorded on the two transects there. Reduced abundances were recorded from a number of other monitoring and reference sites, as shown by the overall decline in the graph below. No dogwhelks were found on the Vidlin Ness (3.8) transect site, where they had been present before the introduction of TBT antifouling paints. They returned to Kirkabister (6.11) (on the opposite side of Vidlin Voe) in 2004 and that population has been maintained.
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Monitoring site no. 4.3 The Kames Nucella lapillus Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 MS ------ - - - - LMS ------ - LS ------ - -
Monitoring site no. 5.1 South of Skaw Taing Nucella lapillus Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
MS ------ - - LMS - - - LS - - - -
Reference site no. 6.11 Kirkabister Nucella lapillus Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 MS ------ ------
LMS ------ - LS ------ - - -
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3.1.12 Flustrellidra hispida & Alcyonidium spp. 2015 was another fairly good year for epiphytic bryozoa growing on lower shore algae, with slightly lower average abundance compared to 2014. There was a more notable reduction at the reference sites, although the missing data from the lower shore station at Kirkabister (6.11) (inaccessible due to the tide) was a factor here.
3.1.13 Red algal turf species An error in the previous methodology used in these reports to calculate mean abundance across multiple algal turf species has been corrected. The error resulted in data from relatively uncommon species having too large an influence on the mean abundance, suggesting larger fluctuations than was really apparent. The graph below shows that the calculated mean abundance of red algal turf has fluctuated relatively slightly over the last few years and is currently at a mid range level.
Fluctuations in abundances and the frequency of records for individual species is greater, and the graphs and table below give examples that show both rises and falls. Mastocarpus stellatus and Lomentaria articulata are generally the most abundant and frequently occurring species, but there are a number of others that reach Common or Abundant at some sites in some years. Osmundea hybrida and O. pinnatifida are southern species that might be expected to become more successful as our climate changes, but this is not yet apparent in the data. None of the observed fluctuations are considered to be related to activities at the terminal.
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The table below shows an example, from the lower shore station at The Kames, of the recorded fluctuations in abundance of 12 species that comprise the red algal turf. P.p. = Palmaria palmata, D.c. = Dumontia contorta, Co. = Corallina, M.s. = Mastocarpus stellatus, C.c. = Chondrus crispus, L.a. = Lomentaria articulata, Ce. = Ceramium, Pl.p. = Plumaria plumosa, M.a. = Membranoptera alata, O.h. = Osmundea hybrida, O.p. = Osmundea pinnatifida, Po. = Polysiphonia
Monitoring site no. 4.3 The Kames, lower shore station Red algal turf species Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
P.p. - - - - - - -
D.c. - - - - - - - - -
Co. - - - M.s. - C.c. - - - - - - - - L.a. -
Ce. ------ - - - -
Pl.p. - - - - - - - - -
M.a. - - - - - -
O.h. - - - - - - - - - - -
O.p. - - - - -
Po. - - - - - - - - - - - -
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The Kames (site 4.3) – Red algal turf (mainly Mastocarpus stellatus), encrusting coralline, green algae (Cladophora rupestris and Ulva (tubular)) and serrated wrack (Fucus serratus), July 2015.
3.1.14 Laminaria digitata Following the recent rise and fall in records of the kelp Laminaria digitata, records in 2015 suggest a slight increase.
Monitoring site no. 4.1 Grunn Taing Laminaria digitata Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 LS ------
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3.1.15 Ascophyllum nodosum Knotted wrack is typically present in fairly high abundance at four sheltered sites in Sullom Voe and one of the reference sites. Its mean abundance at the Sullom Voe sites has been higher in the last 15 years compared to the earlier years and this is due to notable increases at all four sites. A. nodosum is intolerant of physical disturbance and the sites all suffered impacts in the 1970s. Mavis Grind (5.5) lies close to where there used to be quarry workings and an asphalt plant, and a stream, chronically contaminated by oil, ran past the site. A. nodosum was absent from this bedrock site when it was first surveyed in 1980, but abundances gradually increased and have been fairly steady since 1993. The two Scatsta Ness sites (6.12 and 6.13) and South of Jetty 2 (6.2) were physically disrupted by clean-up activity during the Esso Bernicia oil spill response in 1978 and the resulting continued instability of the boulder / cobble substrata. The substrata gradually stabilised and A. nodosum abundances increased, but it is difficult to define when the sites fully returned to the pre-disturbance condition. Abundances from Scatsta Ness (cleared) (6.12) in 2015 are the highest ever recorded there (there is no pre-spill data) and abundances from South of Jetty 2 (6.2) have only shown some stability at pre- disturbance levels since 2013. The only reference site that has sufficient abundance of A. nodosum for comparison with the Sullom Voe sites is N.Burra Voe (6.14), which was only established in 1993. However, those data do suggest no trend, either up or down, over the last 22 years.
Monitoring site no. 6.12 Scatsta Ness (cleared) Ascophyllum nodosum Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS - - MS - - - - - - - - LMS LS - - - -
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Monitoring site no. 6.2 South of Jetty 2 Ascophyllum nodosum Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS ------ MS - - - LMS ------ - - - - - LS ------ - - - -
Monitoring site no. 6.14 N.Burra Voe Ascophyllum nodosum Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS ------ MS
LMS
LS -
3.1.16 Fucus serratus After the high abundances of serrated wrack over the last four years, there was a reduction in 2015. Many sites showed small reductions, but there was an increase at one (Mavis Grind). The unusually high abundance of small F. serratus plants on the lower shore at Voxter Ness in 2014 did not persist, and the species was absent from those monitoring stations. Reductions in abundance were also evident at the reference sites, though there was a notable increase at Vidlin Ness.
Monitoring site no. 5.1 South of Skaw Taing Fucus serratus Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
LMS - - - - - - -
LS
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Monitoring site no. 2.9 Riven Noust Fucus serratus Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 LMS ------ LS
3.1.17 Fucus vesiculosus Mean abundances of bladder wrack remained relatively high in 2015. At a station by station level this average increase is less obvious and there were numerous decreases as well as increases. As noted in previous reports, many of the increases have been most evident at the sites and tidal zones on the edge of its distribution.
Monitoring site no. 4.6 Voxter Ness Fucus vesiculosus Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 MS ------ - LMS LS
Monitoring site no. 3.8 Vidlin Ness Fucus vesiculosus Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 UMS ------ -
MS - - - - LMS - - - LS ------ - -
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N.Burra Voe (site 6.14) – Knotted wrack (Ascophyllum nodosum), colonised by red algae (Vertebrata lanosa). Some bladder wrack (Fucus vesiculosus) at top of photo, July 2015.
3.1.18 Green algae Green algae recorded on these shores are comprised primarily of Ulva (flat and tubular species), Cladophora (also not easily recorded to species except C. rupestris) and filamentous green algae (Chlorophyceae). Large fluctuations in abundance can occur from year to year, but have been relatively limited in recent years. The calculation of mean abundance across multiple green algal species was also affected by an error in previous reports (see Section 3.1.13) and has now been corrected. The flush of Ulva (flat) on the lower mid shore at S. of Swarta Taing (3.5) was no longer present.
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Monitoring site no. 3.5 South of Swarta Taing Ulva (flat) Year 97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 MS ------ - - - LMS - - ------ LS
3.2 Site-specific descriptions
3.2.1 Orka Voe bund The bund, created when Orka Voe was filled in during the construction of the terminal in the late 1970s, is visited during the annual survey for a brief assessment of the condition of the rocky shore communities present. Particular attention is paid to the area of disturbance caused by the installation of the Magnus EOR pipeline in 2004/2005. There were no notable changes in habitat or communities along the bund compared to recent years. Construction work on the east side of Orka Voe, where the pipeline associated with the Laggan- Tormore WOS gas terminal crosses the shore, was still underway during the survey. The shore in that area was therefore not visited.
4 Discussion There were few notable changes in rocky shore communities around Sullom Voe between 2014 and 2015. The fluctuations described in the results sections are all considered to be natural and mostly within typical levels for those shores and the survey methodology. None of the recorded fluctuations is considered to be related to the terminal. One of the few notable changes was the large increase in abundance of juvenile limpets. The last major peak of juvenile limpet abundances was in 1997, but, as discussed at the time, the densities of the adults do not correlate well with previous levels of juveniles. However, it does suggest that over- wintering conditions have been favourable and that the overall high limpet densities will be maintained. Good over-wintering conditions are also suggested by the high survival rates of adult barnacles, which is evident from observations and photographs at many sites in 2014 and 2015. A few longer term changes in the data have been mentioned in the results section, including the apparent increase in numbers of records of the hydroid Clava multicornis, the low densities of rough periwinkles and flat periwinkles since 2000, the recovery of knotted wrack at sites in Sullom Voe, and the increased abundance of serrated wrack and bladder wrack. Most of these have been reported before, but are highlighted again in case readers notice correlations with data from other survey areas.
4.1 Effects of terminal operations and oil spills During the period July 2014 to July 2015 there was one pollution incident reported within Sullom Voe (Simon Skinner, pers. comm.). There was a 20 litre spillage of marine diesel from the tug Dunter into the harbour at Sella Ness in July 2015. It was physically dispersed with no application of chemical dispersant. This was only a week before the rocky shore survey started, but no abnormally high quantities of oil sheens were observed around the harbour. One other small pollution incident (a small quantity of sheen from a light processed oil) from a tanker at the terminal occurred in September 2015, but that was after the current period. The temporary containment area at the top of the shore between Jetty 1 and Jetty 2, following the seepage of oily waste from the dirty water drainage system in August 2012, was still well established.
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Remediation of the site had not yet started. The results of the survey of Transect 6.2 (S. of Jetty 2), which lies approximately 25m north of the bund, still showed no apparent effects from the seepage or bund. Terminal activities during the past 12 months appear to have had no obvious impacts upon the rocky shore communities of Sullom Voe.
5 References Baker, J.M. and Wolff, W.J. (1987) Biological Surveys of Estuaries and Coasts. Estuarine and Brackish Water Sciences Association handbook. Cambridge University Press. 449 pp. Ballantine, W.J. (1961). A biologically-defined exposure scale for the comparative description of rocky shores. Field Studies, 1, 1-19. Hiscock, K. (1983) Assessment of rocky shore surveys in Sullom Voe, 1976-1981. (Contractor: Field Studies Council, Oil Pollution Research Unit, Pembroke.) Unpublished report to Shetland Oil Terminal Environmental Advisory Group. Howson, C.M. and Picton, B.E. (eds.) (1997). The species directory of the marine fauna and flora of the British Isles and surrounding seas. Ulster Museum and the Marine Conservation Society. Belfast. 508 pp. Moore, J.J. (2013). Sullom Voe rocky shore transects monitoring, 1976 to 2012: summary of survey methods and database. A report to SOTEAG from Aquatic Survey & Monitoring Ltd., Cosheston, Pembrokeshire. 16 pp + iii Moore, J.J. and Gubbins, M.J. (in prep). Surveys of dogwhelks Nucella lapillus in the vicinity of Sullom Voe, Shetland, July 2015. A report to SOTEAG from Aquatic Survey & Monitoring Ltd., Cosheston, Pembrokeshire and Marine Scotland Science, Aberdeen. 42 pp +iv.
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Appendix 1 Abundance scales used for intertidal organisms
1. Live barnacles (except B. perforatus) (record adults, spat, cyprids 7. Pomatoceros sp. separately); Littorina neritoides; Littorina neglecta 7 Ex 500 or more per 0.01 m2, 5+ per cm2 5 A 50 or more tubes per 0.01 m2 6 S 300-499 per 0.01 m2, 3-4 cm2 4 C 1-49 tubes per 0.01 m2 2 2 2 3 F 1-9 tubes per 0.1 m 5 A 100-299 per 0.01 m , 1-2 per cm 2 2 2 O 1-9 tubes per m 4 C 10-99 per 0.01 m 2 3 F 1-9 per 0.01 m2 1 R Less than 1 tube per m 2 O 1-99 per m2 1 R Less than 1 per m2
2. Balanus perforatus 8. Spirorbinidae 7 Ex 300 or more per 0.01 m2 5 A 5 or more per cm2 on appropriate substrata; more than 100 6 S 100-299 per 0.01 m2 per 0.01 m2 generally 2 5 A 10-99 per 0.01 m 2 2 4 C Patches of 5 or more per cm ; 1-100 per 0.01 m generally 4 C 1-9 per 0.01 m2 2 3 F 1-9 per 0.1 m2 3 F Widely scattered small groups; 1-9 per 0.1 m generally 2 O 1-9 per m2 2 O Widely scattered small groups; less than 1 per 0.1 m2 1 R Less than 1 per m2 generally 1 R Less than 1 per m2
3. Patella spp. 10 mm+, Littorina littorea (juv. & adults), Littorina 9. Sponges, hydroids, Bryozoa mariae/obtusata (adults), Nucella lapillus (juv., <3 mm). 5 A Present on 20% or more of suitable surfaces. 2 7 Ex 20 or more per 0.1 m 4 C Present on 5-19% of suitable surfaces 6 S 10-19 per 0.1 m2 3 F Scattered patches; <5% cover 5 A 5-9 per 0.1 m2 2 4 C 1-4 per 0.1 m2 2 O Small patch or single sprig in 0.1 m 3 F 5-9 per m2 1 R Less than 1 patch over strip; 1 small patch or sprig per 2 O 1-4 per m2 0.1 m2 1 R Less than 1 per m2
4. Littorina ‘saxatilis’, Patella <10 mm, Anurida maritima, Hyale 10. Flowering plants, lichens, lithothamnia nilssoni and other amphipods, Littorina mariae/obtusata juv. 7 Ex More than 80% cover 7 Ex 50 or more per 0.1 m2 6 S 50-79% cover 6 S 20-49 per 0.1 m2 5 A 20-49% cover 5 A 10-19 per 0.1 m2 4 C 1-19% cover 4 C 5-9 per 0.1 m2 3 F Large scattered patches
3 F 1-4 per 0.1 m2 2 O Widely scattered patches all small 2 O 1-9 per m2 1 R Only 1 or 2 patches 1 R Less than 1 per m2
5. Nucella lapillus (>3 mm), Gibbula sp. Monodonta lineata, Actinia 11. Algae equina, Idotea granulosa, Carcinus (juv. & recent settlement), 7 Ex More than 90% cover Ligia oceanica 6 S 60-89% cover 7 7 Ex 10 or more per 0.1 m2 5 A 30-59% cover 6 S 5-9 per 0.1 m2 5 A 1-4 per 0.1 m2 4 C 5-29% cover 4 C 5-9 per m2, sometimes more 3 F Less than 5% cover, zone still apparent 3 F 1-4 per m2, locally sometimes more 2 O Scattered plants, zone indistinct 2 2 O Less than 1per m , locally sometimes more 1 R Only 1 or 2 plants 1 R Always less than 1 per m2
6. Mytilus edulis, Dendrodoa grossularia Other animal species: 7 Ex 80% or more cover record as percentage cover or approximate numbers within 0.01, 0.1 or 1 m2 6 S 50-79% cover 5 A 20-49% cover 4 C 5-19% cover 3 F Small patches, 5%, 10+ small individuals per 0.1 m2, 1 or more large per 0.1 m2 2 O 1-9 small per 0.1 m2 1-9 large per m2; no patches except small in crevices 1 R Less than 1 per m2
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Appendix 2 Chronology of personnel changes and methodology during SOTEAG rocky shore monitoring programme Contractors: Oil Pollution Research Unit, Field Studies Council Research Centre, Cordah Ltd., BMT Cordah Ltd., Aquatic Survey & Monitoring Ltd. Survey staff: Annette Little (AL), Tony Thomas (AT), Ben James (BJ), Christine Howson (CH), David Emerson (DE), David Levell (DL), Frank Fortune (FF), Harry Goudge (HG), Heather Howcroft (HH), John Addy (JA), Jenny Baker (JB), John Crothers (JC), John Hartley (JH), Jon Moore (JM), Keith Hiscock (KH), Kingsley Iball (KI), Lou Luddington (LL), Peter Taylor (PT), Sue Hiscock (nee. Hainsworth) (SH), Tom Mercer (TM). Sites: No. of sites within Sullom Voe and adjacent part of Yell Sound + No. of reference sites (dogwhelks refers to the associated monitoring of dogwhelks; see Moore and Gubbins 2015) Year Contractor Survey staff Sites Stns Methods (see Moore 2013 for explanation) Month 1976 OPRU JB, KH, SH, DL, JA, JH 30 + 4 All Full survey May 1977 OPRU JB, SH, KH, JC, DE, AT 34 + 9 All Full survey May 1978 OPRU KH, JC, AT, AL 18 + 2 All Full survey May 1979 OPRU KH, AT, DE, HH 21 + 2 All Full survey May 1980 OPRU KH, JC, DE, AT 25 + 2 All Full survey May 1981 OPRU KH, DE, AT, KI 25 + 2 All Full survey May/June 1982 Not surveyed 1983 Not surveyed 1984 OPRU KH 25 All Rapid survey August 1985 OPRU KH 25 All Rapid survey August 1986 OPRU KH 25 All Rapid survey August 1987 OPRU CH 23 All Rapid survey August 1988 FSCRC (OPRU) CH, AL 23 All Rapid survey, reestablishment of 6 transects August 1989 FSCRC (OPRU) AL, TM 23 All Rapid survey, reestablishment of 2 transects August 1990 FSCRC (OPRU) JM, PT 23 All Rapid survey August 1991 FSCRC (OPRU) JM, PT 23 All Rapid survey (+ dogwhelks) August 1992 FSCRC (OPRU) PT, JM 23 All Rapid survey July/Aug 1993 FSCRC (OPRU) JM, PT 15 + 5 5 Full survey (+ dogwhelks) August 1994 FSCRC (OPRU) JM, AL 15 + 5 5 Full survey August 1995 FSCRC (OPRU) JM, AL 15 + 5 5 Full survey (+ dogwhelks) August 1996 OPRU JM, AL 15 + 5 5 Full survey August 1997 OPRU JM, AL 15 + 5 5 Full survey (+ dogwhelks) August 1998 Cordah JM, BJ 15 + 5 5 Full survey August 1999 Cordah BJ, JM 15 + 5 5 Full survey (+ dogwhelks) July/Aug 2000 Cordah JM, BJ 15 + 5 5 Full survey August 2001 BMT Cordah FF, JM 15 + 5 5 Full survey (+ dogwhelks) July/Aug 2002 BMT Cordah FF, JM 15 + 5 5 Full survey July 2003 BMT Cordah FF, JM 15 + 5 5 Full survey July/Aug 2004 BMT Cordah JM, FF 15 + 5 5 Full survey (+ dogwhelks) July/Aug 2005 BMT Cordah JM, FF 15 + 5 5 Full survey July 2006 ASML JM, CH 15 + 5 5 Full survey August 2007 ASML JM, LL 15 + 5 5 Full survey (+ dogwhelks) July/Aug 2008 ASML JM, CH 15 + 5 5 Full survey August 2009 ASML JM, CH 15 + 5 5 Full survey (+ dogwhelks) August 2010 ASML JM, CH 15 + 5 5 Full survey July/Aug 2011 ASML JM, HG 15 + 5 5 Full survey (+ dogwhelks) August 2012 ASML JM, CH 15 + 5 5 Full survey July 2013 ASML JM, CH 15 + 5 5 Full survey (+ dogwhelks) July 2014 ASML JM, CH 15 + 5 5 Full survey July/Aug 2015 ASML JM, CH 15 + 5 5 Full survey (+ dogwhelks) July
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Aquatic Survey & Monitoring Ltd. December 2015