Page 165 - Alderney Regional Environmental Assessment of Renewable Energy: Environmental Report

Alderney Regional Environmental Assessment of Renewable Energy:
Environmental Report
Seaweeds have been studied at the site for numerous years, with around 100 species recorded
and the potential for many more to be identified. Of particular importance is knotted wrack
Ascophyllum nodosum, due to its specific habitat requirements and the fact that up to 75% of
the world’s population is found in the UK. The red seaweed Halymenia latifolia is also
considered to be of conservation importance following a 25-49% decline in Great Britain over
the last 25 years. The diversity of seaweeds around Alderney and within the Ramsar site plays
an important role in supporting the marine fauna and nesting bird populations in the area
(Alderney Wildlife Trust, 2012).
2) Longis Nature Reserve: This reserve contains a number of UK BAP species and
habitats. The site was designated under a memorandum of understanding in 2003 between the
Alderney Wildlife Trust, the States of Alderney and local land owners. Situated on the east of
the island, Longis reserve is the largest terrestrial reserve on Alderney, covering 105 hectares,
and contains 18 recorded biotopes including marine, intertidal, coastal heathland, grassland,
scrub woodland habitats and both natural and man-made freshwater ponds. The reserve
contains a high diversity of plant species, and provides an important site for migratory birds,
mammals and insect species. Nearly 100 insects of national importance are present within the
Longis Nature Reserve, many of which have not yet occurred in the UK (Alderney Wildlife Trust
website).
3) Val du Saou Nature Reserve: This reserve is the smallest on the island and was
designated under a memorandum of understanding in 2004 between the Alderney Wildlife
Trust, the States of Alderney and two private landowners. The reserve is on the southern coast
of Alderney and comprises coastal cliff top woodland valley habitats and covers 7 hectares.
The site supports a variety of migratory birds, the island’s only reptile, the slow worm Anguis
fragilis and many important insect species (Alderney Wildlife Trust website).
4) Alderney South Banks Subtidal Sandbank: Alderney’s South Banks is of nature
conservation importance and would meet the criteria for designation as a subtidal sandbank
under the EC Habitats Directive. As Alderney is not a member of the EU full designation may
not occur, however, the Commission is committed to adopting best practice and has therefore
recommended that the site receive the same consideration as a fully designated SAC. Shallow
sandy sediments such as the South Banks typically support burrowing fauna, crustaceans,
bivalve molluscs and echinoderms. Mobile epifauna at the sand surface usually include
shrimps, gastropod molluscs, crabs and fish. Notable fish species found on sand banks include
sandeels Ammodytes spp., an important food source for seabirds, the critically endangered
common skate Dipturus batis and the thornback ray Raja clavata. Communities of foliose
seaweeds, hydroids, bryozoans and ascidians may form on more stable stones and shells on
the sediment (Axelsson et al., 2011).
Designated Sites Within the Wider Study Area: There are a number of Natura 2000 and
Ramsar sites in the wider study area that are designated for a range of mobile interest features
(i.e. marine mammals, birds and migratory fish). These mobile features could be using
Alderney and its surrounding waters and, therefore, could potentially overlap with the impacts
brought about by the Draft Plan. The nearest Natura 2000 sites and Ramsar sites on the
adjacent French Cotentin Peninsula and within the other Channel Islands are shown on Figure
20 and include the following, which are designated for mobile interest features:
R/4001/7 141 R.2129