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
Bannerman's shearwater Bannerman's shearwater Bannerman's shearwater ("Puffinus bannermani") is a seabird in the Procellariidae family formerly considered conspecific with Audubon's shearwater ("Puffinus lherminieri"). Little is known of this species other than that it breeds in the Volcano Islands in the Ogasawara Group to the southwest of Japan and doesn't seem to range far from this area. The species population size has not been estimated but is assessed to be decreasing. Not much is known about this species and more research is required to obtain an understanding of its ecology. Based on the ecology of closely related species, "P. bannermani" is thought likely