Audubon's shearwater underparts are white, as is the head below eye level. The iris is dark, the feet are dull pink with a black wash and black toenails, and the bill is grey, darker towards the tip, and with a pinkish hue. Males and females look alike. Immature birds do not have a distinct plumage, while the nestlings are covered with down feathers, grey above and whitish on the belly. It can be confused with the Manx shearwater ("P. puffinus"), which has white undertail coverts and in direct comparison a longer bill. Other similar-looking species are usually completely allopatric, though the largely
Galápagos shearwater white. It sometimes has a dark collar. Both sexes are alike, as are the young after fledging. It is a slender-bodied shearwater, about 29–31 cm long, with a wingspan of around 63 cm and weighs 123-225 g. The species closely resembles the tropical shearwater, although the latter is typically blacker and has a longer tail. The Galápagos shearwater is a gregarious species and will feed at sea with other shearwaters and boobies. It flies low over the water and feeds on squid, fish and offal. It intersperses 4-10 stiff wing beats with shallow glides. Galápagos shearwater The Galápagos shearwater ("Puffinus