Page 69 - Alderney Regional Environmental Assessment of Renewable Energy: Environmental Report

Alderney Regional Environmental Assessment of Renewable Energy:
Environmental Report
which was present at all three surveyed sites and is likely to be widespread around Alderney,
and IR.HIR.KFaR - Kelp park on high energy infralittoral rock and boulders - which was present
at both Ortac (Site 2b) and Coque Lihou (Site 3b) and is likely to reflect the strong tidal currents
at these sites. CR.HCR.XFa.SpAnVt - Steep or vertical bedrock walls with a fauna turf of
sponges and anemones was present on the gulley walls at Renonquet (Site 1b) and had the
most diverse fauna of any of the Alderney habitats. It differs a little from the biotope
classification because of the presence of the orange sea-squirt, Stolonica socialis, in significant
numbers, but this variation, which may be a southerly one, is also common in Sark and is found
in South Devon. CR.HCR.FaT.CTub - Tide-swept steep or vertical bedrock walls dominated by
oaten pipe hydroids, Tubularia indivisa, and sponges was present at both Ortac (Site 2b) and
Coque Lihou (Site 3b) and was characterised by a less varied sessile fauna than at Renonquet
(Site 1b), dominated by oaten pipe hydroids, Tubularia indivisa. There were significant
numbers of anemones in this habitat - elegant anemones, Sagartia elegans, at Coque Lihou
and jewel anemones, Corynactis viridis , and Devonshire cup-corals, Caryophyllia smithii, at
both sites.
Seasearch 2010 Survey
A further nine sites were surveyed in more detail by Seasearch in 2010 along the southeastern
coastline of Alderney (Figure 11) (Wood, 2010). A total of 212 species were recorded for the
survey as a whole comprising 106 animals and 106 plants (Table 11). The total for all the
Seasearch surveys to date in Alderney is 194 animals and 150 plants. The sites with the
greatest diversity in 2010 overall were Rousset (Site 6c) and La Tchue (Site 7c). The site with
the greatest diversity of animal life was La Tchue which was significantly more diverse than any
other site. In terms of plants recorded these were more evenly spread across sites with
Rousset, La Tchue, Les Boufresses (Site 2c) and Queslingue (Site 4c) all reasonably diverse
(Wood, 2010).
Table 11. Groups of flora and fauna identified during all the Seasearch surveys
Flora and Fauna Taxa Total Recorded
Sponges Porifera 35
Jellyfish, hydroids, anemones and corals Cnidaria 33
Flatworms Platyhelminthes 1
Segmented worms Anellida 8
Barnacles, crabs, prawns and lobsters Crustacea 16
Shells, bivalves and sea slugs Mollusca 30
Sea mats and sea mosses Bryozoa 15
Horseshoe worms Phoronida 1
Starfish, sea urchins and sea cucumbers Echinodermata 12
Sea squirts Tunicata 16
Fishes Pisces 27
Red seaweeds Rhodophycota 101
Brown seaweeds Phaeophyceae 35
Green seaweeds Chlorophyceae 13
Flowering plants Angiospermae 1
(Wood, 2010)
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