The Grey Seal (Halichoerus grypus, meaning "hooked-nosed sea pig") is found on both shores of the North Atlantic Ocean. It is a large seal of the family Phocidae or "true seals". It is the only species classified in the genus Halichoerus. Its name is spelled Gray Seal in the US; it is also known as Atlantic Grey Seal and the Horsehead Seal.


It is a medium sized seal, with the bulls reaching 2.5–3.3 m long and weighing up to 300 kg; the cows are much smaller, typically 1.6–2.0 m long and 100–150 kg weight. It is distinguished from the Common Seal by its straight head profile with nostrils that are well apart, and fewer spots on its body. Bull Greys have larger noses and a more convex profile than Common Seal bulls. Males are often darker than females, with lighter patches and often scarring around the neck. Females are silver grey to brown with dark patches.

Ecology and DistributionEdit

In Great Britain and Ireland, the Grey Seal breeds in several colonies on and around the coasts; notably large colonies are at Donna Nook (Lincolnshire), the Farne Islands off the Northumberland Coast (about 6,000 animals), Orkney and North Rona off the north coast of Scotland, Lambay Island off the coast of Dublin and Ramsey Island off the coast of Pembrokeshire.

In the Western North Atlantic, the Grey Seal is typically found in large numbers in the coastal waters of Canada and south to about New Jersey in the United States. In Canada, it is typically seen in areas such as the Gulf of St. Lawrence, Newfoundland and the Maritimes, and Quebec. The largest colony in the world is at Sable Island. In the United States it's found year round off the coast of New England, in particular Maine and Massachusetts, and slightly less frequently in the Middle Atlantic States. Its natural range extends south to Virginia.

An isolated population exists in the Baltic Sea,[2] forming the H. grypus balticus subspecies.

During the winter months Grey Seals can be seen hauled out on the rocks, islands, and shoals not far from shore, and occasionally coming ashore to rest. In the spring the recently weaned pups and yearlings occasionally strand on beaches after becoming "lost."