Bonin petrel
The Bonin petrel (Pterodroma hypoleuca) is a seabird in the family Procellariidae. It is a small gadfly petrel. 995,000 individuals, about 99% of the total population, breed on the Northwestern Hawaiian Islands, while 5,000 individuals (1% of the population) breed off the coast of Japan on the Bonin and Volcano Islands. Its secretive habits and limited range have resulted in few studies and many aspects of the species' biology are poorly known.
Description and taxonomy
The Bonin petrel is a small gadfly petrel, 30 cm long with a wingspan of around 67 cm. It has a white head with a black cap and face markings; overall the head often has a scaled appearance. Its pale grey upperparts have darker primaries and wing coverts creating an "M" mark across the back. The underwing is white with dark edging and a patch at the carpal joint and across underwing coverts. The tail is dark grey, and the rest of the plumage is white, except for a dark half collar on the breast. Like the rest of the Pterodroma petrels the black bill is short and hooked. The legs and feet are pink with dark patches.