Size: 11.07 hectares

% of total area of SSSI's: 2.72

Designated features: Atlantic Grey Seal & Cormorant

General Description

Lying immediately west of Bryher and Samson, the Norrad rocks comprise a series of small uninhabited islands including Gweal, Maiden Bower, Castle Bryher and Mincarlo, along with numerous other isolated rocks and ledges.  These islands are completely exposed to the elements, which has limited the vegetation such that only 6 species have only been recorded including; Tree Mallow, Thrift, Sea Beet, Common Scurvygrass and Rock Sea-Spurrey.  But, these islands however are particularly important for their breeding seabird colonies.  The Norrad Rocks supports some 10 species of breeding seabird, with Mincarlo being particularly important as it supports the largest colony of Cormorants and Puffin on Scilly, as well as being only one of 4 sites in the archipelago for breeding Storm petrel.  Other seabirds also include Fulmar, Razorbill, Guillemot and four species of Gull.

Away from the main islands the isolated rocks and ledges also provide some of the most important breeding sites on Scilly for Atlantic Grey Seal.

Practical Management

As with all our breeding seabird colonies, peace, quiet and minimal disturbance is required.  The Trust’s work focuses on annual monitoring of our seabirds, which is carried out by boat, with a fuller survey every 6 years which requires 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 populations around the country and the health of our seas. The Trust is also about to begin 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.