Newell's shearwater donkey-like braying call around the breeding areas. Townsend's shearwater ("P. auricularis") is very similar but has dark undertail-coverts, a shorter tail and a less sharp boundary between the black and white on the face. It was described as a new species "Puffinus newelli" in 1900 by the American ornithologist Henry Wetherbee Henshaw using specimens obtained by Brother Matthias Newell from residents of Maui. It was later included by some authors in the Manx shearwater ("Puffinus puffinus") as was Townsend's shearwater ("Puffinus auricularis"). Later, Townsends's shearwater was raised back to species status with Newell's shearwater as a subspecies of it. This
Wedge-tailed shearwater (in common with the other shearwaters) as an adaptation for swimming. This species is related to the pan-Pacific Buller's shearwater, which differs much in colour pattern, but also has a wedge tail and a thin black bill. They make up the "Thyellodroma" group, a superspecies of the large shearwaters that were for a long time included in the genus "Puffinus". Wedge-tailed shearwaters feed pelagically on fish, squid and crustaceans. Their diet is 66% fish, of which the most commonly taken is goatfish. It was thought that the species mostly took food from surface feeding, observations of feeding wedge-tails suggested that