Cameron Rutt (Blooming Glen, Pennsylvania, USA) writes in the journal Western Birds on hybridization in the Black-Footed Phoebastria nigripes and Laysan P. immutabilis Albatrosses. Nice pics, including of birds flying and on the sea.
The paper’s abstract follows:
“Although the Laysan (Phoebastria immutabilis) and Black-footed Albatrosses (P. nigripes) have been known to hybridize for more than a century, little has been published regarding plumage variation of the hybrid progeny. During six months of field work on Laysan, Hawaii, I noted 13 possible hybrids (five presumed F1 hybrids, three possible F2 backcrosses with the Black-footed Albatross, and at least four possible F2 backcrosses with the Laysan Albatross). Apparent F2 backcrosses with the Black-footed Albatross differ from it most noticeably in their black-and-white underwings and much more extensive white circling the face. Apparent F2 backcrosses with the Laysan Albatross differ from that species most noticeably in their extensive gray smudging throughout the body and darker underwing coverts. Apparent F2 backcrosses interbreed with the Black-footed Albatross, the first evidence of any hybrid pairing with that parental species.”
A Black-footed-Laysan Albatross hybrid, photograph by Lindsay Young
Rutt, C 2013. Hybridization of the Black-Footed and Laysan Albatrosses. Western Birds 44: 322-333.
John Cooper, ACAP Information Officer, 14 February 2014