The Island's waters are home to a sizeable seal population, the vast majority of which are Grey Seals (also known as Atlantic Grey Seals). Half the world's population of Greys can be found around the British coast.
Grey Seals can be seen in particularly strong numbers at the Calf Sound, where they 'haul out' onto the rocks at low tide. The Greys (halichoerus grypus) are recognizable by their long, 'romanesque' profile. Their colouring can vary greatly, from dark brown to grey, or sometimes speckled grey and cream. Females (or 'cows') tend to be paler than the males (or 'bulls'), which are also much larger.
They mainly feed on fish but sometimes eat crustaceans, squid and octopus too. The cows come ashore to breed and give birth, and the pups - which initially have a white coat - begin to appear in autumn.
Common Seals (phoca vitulina), also known as Harbour Seals, are also seen but more infrequently and in far smaller numbers. They are smaller than the Greys and distinguished by a rounder, more 'pup-like' head, with curvature between the eyes and snout. Their coats also vary greatly in colour, from black or brown to grey or tan.