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
Hutton's shearwater a white underbelly and brown collar, dark borders to the underwing, dark grey bill, and pinkish dark-webbed feet; it can be distinguished from fluttering shearwater by its dark grey "armpits". At a breeding colony it has a loud cackling call. Hutton's shearwater feeds in the open ocean largely on small fish and krill, diving up to 20 m. "Puffinus huttoni" have long bills, which are adapted to catch prey more or less underwater by plunging from a few meters above the surface or by paddling slowly forwards searching with their head submerged, then diving using partly opened wings for propulsion.