The Sooty Shearwater (Puffinus griseus) is a medium-large shearwater in the seabird family Procellariidae. In New Zealand it is also known by its Māori name tītī and as "muttonbird", like its relatives the Wedge-tailed Shearwater (P. pacificus) and the Australian Short-tailed Shearwater (P. tenuirostris).
It appears to be particularly closely related to the Great ("P." gravis) and Short-tailed Shearwaters, all blunt-tailed, black-billed species, but its precise relationships are obscure. In any case, these three species are among the larger species of shearwater which might belong into a separate genus Ardenna.
Read more about Sooty Shearwater: Description, Distribution and Movements, Ecology and Status, Inspiration For Hitchcock's The Birds