Audubon's shearwater ill-resolved clade also including such species as the little shearwater, the Manx shearwater ("P. puffinus") or the black-vented shearwater ("P. opisthomelas"). The little-known Heinroth's shearwater ("P. heinrothi") is sometimes considered a subspecies of either Audubon's or the little shearwater. Though it is likely to be another member of that close-knit group, its actual relationships remain uncertain due to lack of specimens. Audubon's shearwater itself has around 10 subspecies. Several have at one time or another been suggested to constitute separate species. For example, the Galápagos Islands population has turned out to be a very distinct species, the Galápagos shearwater ("P.
Arripis commensal relationship between the Australian salmon and the birds is noted to be especially strong in such species as the white-fronted tern, ("Sterna striata"), fluttering shearwater, ("Puffinus gavia"), and Buller's shearwater, ("Puffinus bulleri"). The baitfish made available by the Australian salmon's herding behaviour may also be important to the reproductive success of winter-nesting birds; the decline of the Australians salmon stocks has evoked concern for these bird species, some of which – such as the fairy tern, ("Sterna nereis") – are endangered Aside from seabirds, the Australian salmon are also important in the diets of cetaceans, such as killer whales