Yelkouan shearwater Menorca. A study of these birds recommended that a combination of morphological characteristics and DNA sequence data should be required at least for scientific purposes to assign individual birds to either species. It was formerly considered a subspecies of the Manx shearwater (see there for more on the "Puffinus puffinus" superspecies). After the first split, it was the nominate subspecies of the so-called "Mediterranean shearwater" for nearly ten more years; it is considered a monotypic species now, as the Balearic form "mauretanicus" has been separated as the Balearic shearwater. The yelkouan shearwater appears to belong to a group of Mediterranean
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