Shearwater, any bird of the genus Puffinus of the Petrel family, with about twenty species, universally distributed. The wings are long and pointed; the nostrils open separately; the three front toes are webbed, and the hind toe is very small. All the species are oceanic, and swim well, though they rarely dive, feeding on fish that frequent the surface. Some are nooturnal in habit, or partially so. Four species visit Britain: the Great Shearwater (P. major) is generally met with on the south coast, the Dusky Shearwater (P. griseus) has been taken there, and also on the east coast; the Dusky Shearwater (P obscurus) is but an occasional visitor. The Manx Shearwater (P. anglorum), by far the commonest, is about the size of a pigeon, black above and white below. It breeds in Wales and in the Orkneys. All these birds lay a single white egg in a hole in the ground.