ISSN 1393 – 6670 N A T I O N A L P A R K S A N D W I L D L I F E S ERVICE THE MONITORING AND ASSESSMENT OF SIX EU HABITATS DIRECTIVE ANNEX I MARINE HABITATS Louise Scally, Nick Pfeiffer and Elizabeth Hewitt I R I S H W I L D L I F E M ANUAL S 118 National Parks and Wildlife Service (NPWS) commissions a range of reports from external contractors to provide scientific evidence and advice to assist it in its duties. The Irish Wildlife Manuals series serves as a record of work carried out or commissioned by NPWS, and is one means by which it disseminates scientific information. Others include scientific publications in peer reviewed journals. The views and recommendations presented in this report are not necessarily those of NPWS and should, therefore, not be attributed to NPWS. Front cover, small photographs from top row: Coastal heath, Howth Head, Co. Dublin, Maurice Eakin; Red Squirrel Sciurus vulgaris, Eddie Dunne, NPWS Image Library; Marsh Fritillary Euphydryas aurinia, Brian Nelson; Puffin Fratercula arctica, Mike Brown, NPWS Image Library; Long Range and Upper Lake, Killarney National Park, NPWS Image Library; Limestone pavement, Bricklieve Mountains, Co. Sligo, Andy Bleasdale; Meadow Saffron Colchicum autumnale, Lorcan Scott; Barn Owl Tyto alba, Mike Brown, NPWS Image Library; A deep water fly trap anemone Phelliactis sp., Yvonne Leahy; Violet Crystalwort Riccia huebeneriana, Robert Thompson Main photograph: A Kelp park, Nick Pfeiffer The monitoring and assessment of six EU Habitats Directive Annex I Marine Habitats Louise Scally, Nick Pfeiffer and Elizabeth Hewitt Citation: Scally, L., Pfeiffer, N. and Hewitt, E. (2020) The monitoring and assessment of six EU Habitats Directive Annex I Marine Habitats. Irish Wildlife Manuals, No. 118. National Parks and Wildlife Service, Department of Culture, Heritage and the Gaeltacht, Ireland. Keywords: Sandbanks which are slightly covered by sea water all the time, Estuaries, Mudflats and sandflats not covered by seawater at low tide, Large shallow inlets and bays, Reefs, Submerged or partially submerged sea caves. The NPWS Project Officer for this report was: Yvonne Leahy; [email protected] This IWM was edited by Yvonne Leahy, Cliona O’Brien and Áine O Connor ISSN 1393 – 6670 An tSeirbhís Páirceanna Náisiúnta agus Fiadhúlra 2020 National Parks and Wildlife Service 2020 An Roinn Cultúir, Oidhreachta agus Gaeltachta, 90 Sráid an Rí Thuaidh, Margadh na Feirme, Baile Átha Cliath 7, D07N7CV Department of Culture, Heritage and the Gaeltacht, 90 North King Street, Smithfield, Dublin 7, D07 N7CV Contents Executive Summary .............................................................................................................................................. i Acknowledgements ............................................................................................................................................... i 1 Introduction ................................................................................................................................................... 1 2 Methods ......................................................................................................................................................... 4 2.1 Background .......................................................................................................................................... 4 2.2 Field Survey methods ......................................................................................................................... 4 2.2.1 Subtidal sediments ......................................................................................................................... 4 2.2.2 Intertidal sediments ........................................................................................................................ 5 2.2.3 Keystone Communities .................................................................................................................. 6 2.2.4 Littoral hard substratum (Intertidal reef) .................................................................................. 13 2.2.5 Sublittoral hard substratum (Subtidal reef) .............................................................................. 15 2.2.6 Submerged or Partially Submerged Sea Caves [8830] .................................................................... 15 2.3 Data analysis ...................................................................................................................................... 16 2.3.1 Data manipulation and transformations ................................................................................... 17 3 Conservation Assessment.......................................................................................................................... 18 3.1 Range ................................................................................................................................................... 18 3.2 Area ...................................................................................................................................................... 18 3.3 Structure & functions .......................................................................................................................... 18 3.4 Future prospects .................................................................................................................................. 20 3.5 Overall site assessment..................................................................................................................... 21 4 Results .......................................................................................................................................................... 22 4.1 Sandbanks which are slightly covered by sea water all the time [1110] .............................................. 22 4.2 Estuaries [1130] ................................................................................................................................... 23 4.3 Mudflats and sandflats not covered by seawater at low tide [1140] .................................................... 26 4.4 Large shallow inlets and bays [1160] ................................................................................................... 28 4.5 Reefs [1170] ......................................................................................................................................... 31 4.6 Submerged or partially submerged sea caves [8330] ........................................................................... 34 5 Discussion .................................................................................................................................................... 36 5.1 Sandbanks which are slightly covered by sea water all the time [1110] .............................................. 36 5.2 Estuaries [1130] ................................................................................................................................... 36 5.3 Mudflats and sandflats not covered by seawater at low tide [1140] .................................................... 37 5.4 Large shallow inlets and bays [1160] ................................................................................................... 37 5.5 Reefs [1170] .......................................................................................................................................... 39 5.6 Submerged or partially submerged sea caves [8330] ............................................................................ 40 5.7 Conclusion .......................................................................................................................................... 40 6 References ................................................................................................................................................... 41 Appendix 1 Sediment Marine Community Types sampled within each SAC ...................................... 44 Appendix 2 Reef Marine Community Types sampled within each SAC ............................................... 48 IWM 118 (2020) Monitoring and Assessment of Annex I Marine Habitats Executive Summary This report presents details of a monitoring survey to assess the conservation status of six marine Annex I habitats conducted between 2016 and 2018. This included Sandbanks which are slightly covered by sea water all the time [1110], Estuaries [1130], Mudflats and sandflats not covered by seawater at low tide [1140], Large shallow inlets and bays [1160], Reefs [1170] and Submerged or partially submerged sea caves [8330]. The conservation status of Sandbanks which are slightly covered by sea water all the time, Reefs1 and Submerged or partially submerged sea caves was assessed as Favourable. The conservation status of Estuaries and Mudflats and sandflats not covered by seawater at low tide was assessed as Unfavourable- Inadequate while Large shallow inlets and bays was assessed as Unfavourable-Bad. The principle reason for the failure of a site to meet Favourable conservation status was an increase in fine sediments, a reduction in the extent or abundance of an area mapped for one or more keystone communities, and/or an increase in invasive alien species (IAS). The main pressures acting on the sites were agriculture, commercial forestry, urbanisation (resulting in effluent discharge and storm water run-off) and aquaculture, together with the in-combination effects of these pressures. Future threats are considered to be those