Scilly's Nature Designations SSSI's Western Rocks Size: 9.51 % of total area of SSSI's: 2.34 Designated features: Aggregations of breeding seabirds, Shag & Atlantic Grey Seal General Description Situated between Annet SSSI and the Bishop Rock lighthouse lie a series of small uninhabited islands, including; Great Crebawethan, Rosevear, Rosevean, Gorregan, Melledgan and Hellweathers, along with numerous isolated rocks and ledges. The highest point above sea level is on Rosevean at 17m, which means these islands experience the full force of the Atlantic, south-west gales and sea spray. As a result only one island, Rosevear is vegetated with only 5 species being recorded. These islands are best known and particularly important for their breeding seabird colonies, totalling 11 species. The Western Rocks boast the largest breeding colony across the archipelago of European Shag, with numbers that are of national importance, particularly large numbers are found on Rosevear. The island of Gorregan is particularly important for Razorbill and Guillemot, whilst Melledgan is important for Cormorant. Storm Petrel is known to breed in some of the granite boulder beaches throughout these islands, along with other seabirds including Puffin, Fulmar, Great Black-backed, Lesser Black-backed and Herring Gulls. The isolated rocks and ledges are also important sites for Atlantic Grey Seals, which can be seen, hauled up at low tide throughout the year. Practical Management As with all our breeding seabird colonies, what is required is peace, quiet and minimal disturbance. The Trust’s work focuses on annual monitoring of our seabirds, which is carried out by boat, with a survey once every 6 years which requires any form of landing. Maintaining a watching brief over our seabirds ensures that we are able to provide data which can be used to ascertain the health of seabird populations around the country and the health of our seas. We are also starting regular surveys (by boat) of our Atlantic Grey Seal populations . Atlantic Grey Seals are transient creatures that travel many miles between sites, to breed, rest or feed. The Isles of Scilly are thought to be a key staging point for Grey Seals who move between the South-west coast of England and France. These surveys will help to identify not only numbers of Grey Seals present throughout the year on Scilly, but also key individuals and their movements between these shores. This data should help to identify key areas for Grey Seals in both countries, so that protection can be afforded to our top mammal at these sites.