The razorbill is a medium-sized seabird. It is black above and white below. It has a thick black beak which is deep and blunt, unlike the thinner bill of the similar guillemot. It breeds around the coast of the UK, with the largest colonies in northern Scotland. There are none breeding between the Humber and the Isle of Wight. Birds only come to shore to breed, and winter in the northern Atlantic. The future of this species is linked to the health of the marine environment. Fishing nets, pollution and declining fish stocks all threaten the razorbill.