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
Frederick Wollaston Hutton in 1891. He was founding President of the Royal Society of New Zealand from 1904 to his death in 1905; he was followed by Sir James Hector. He worked successively at the Colonial Museum, Wellington (1871–1873); Otago Museum, Dunedin (1877–1879); and the Canterbury Museum, Christchurch (1887–1905) Hutton died on the return voyage from England on 27 October 1905, and was buried at sea off Cape Town, South Africa. He is commemorated in the Hutton Memorial Medal and Research Fund, awarded for scientific works bearing on the zoology, botany or geology of New Zealand. Hutton's shearwater ("Puffinus huttoni"), a sea bird,