2014 NE Flamborough Head SAC Subtidal Reef SCUBA Diving Survey

notPlanned

"Natural England contracted Seastar Survey Ltd. to undertake survey work in order to assess the condition of part of the Flamborough Head SAC reef features.The main survey aim was to monitor and assess the condition of the Flamborough Head SAC, focusing on the following Annex I subtidal reef sub-features: Kelp forest communities turf communities daim was to assess the species composition of the characteristic biotopes within the kelp forest and faunal turf sub-features by analysing the presence and abundance of composite species, using in-situ observations as well as still and video photography. The subtidal monitoring initiated in 2002 provided a partial baseline for long-term monitoring under the Habitats Directive (Howson et al., 2003). The current survey follows on from the 2002 survey work, attempting to improve the existing baseline and collect robust quantitative data, which will inform site managers of any adaptations to the SAC management that may need to be made in the future. Main findingsdive surveys Flamborough Head were completed successfully between 21st and 23rd July and 2nd and 4th September 2014 with a total of 48 person-dives (24 in July and 24 in September). The effort and results of these surveys are summarised as follows: A total of nine different scuba-divers were used. All divers were qualified to a minimum of advanced diver (CMAS 3-star or equivalent). The scuba-diving quadrat survey methodology as detailed in Axelsson et al. (2013) was used for the 2014 Flamborough Head SAC dive surveys. The dive surveys involved laying a ground line and carrying out quadrat based survey work at 30 random locations along the ground line to generate quantitative data on species composition of the community. For the kelp forest community sub-feature six kelp taxa were recorded: Laminaria hyperborea, Laminaria digitata, Saccharina latissima, Saccorhiza polyschides, Alaria esculenta and kelp juveniles. For the kelp understorey community 11 target algal species were recorded, including the five characteristic species: Delesseria sanguinea, Phycodrys rubens on kelp stipes), Dilsea carnosa, Halurus equisetifolius, Ptilota gunneri, Odonthalia dentata, Calliblepharis ciliata, Taonia atomaria, Dictyota dichotoma, Plocamium cartilagineum and Callophyllis laciniata. A total of 22 faunal species were recorded at the faunal turf sites, including the three characteristic species - Archidistoma aggregatum, Polymastia boletiformis and Thuiaria thuja. A total of 12 dive locations were surveyed during the 2014 survey resulting in 12 monitoring locations spread geographically around Flamborough Head. Six locations were kelp communities and six were faunal turf communities. Of the six kelp sites four were to the south of Flamborough Head and two were to the north. Of the six faunal turf sites four were to the south of Flamborough Head and two were to the north. The highest overall kelp density (36.4 plants/m2was found FH08 (on the north side of the headland) followed by FH13 and FH21. The lowest kelp density was found at FH01 and FH02 (1.6 plants/m2 and 3.6 plants/m2 respectively). Laminaria hyperborea was the dominant kelp taxon on the north side of Flamborough Head, whereas there was a mixture of Saccharina latissima and Laminaria hyperborea on the south side Plocamium cartilagineum was the dominant red algae species at FH21, FH08 and FH12, Polysiphonia spp. was the dominant red algae taxa at FH01 and FH02, and Ceramium spp. was dominant at FH13. d The characteristic algae species Taonia atomaria and Calliblepharis ciliata were found at sites to the south of Flamborough Head, and Ptilota gunneri and Odonthalia dentata were recorded at sites to the north. Halurus equisetifolius was not recorded at any of the sites. All of the faunal turf sites generally had similar species present but at different abundances. Bryozoan turf was dominant, with Alcyonidium diaphanum, Alcyonium digitatum, Flustra foliacea and Nemertesia antennina present at most sites. The characteristic faunal turf species, Archidistoma aggregatum and Thuiaria thuja were recorded at one site to the south of the headland, but Polymastia boletiformis was not found at any of the sites. Ten different biotopes were tentatively assigned based on the data collected in 2014 - five for the kelp sites and five for the faunal turf sites. d The Flamborough Front appears to be leading to a biogeographical divide in the distributions of some species to the north and south of the headland, including Taonia atomaria, Calliblepharis ciliata and Ptilota gunneri. d"