Fork-tailed Storm-Petrel: Medium storm-petrel, blue-gray upperparts, pale gray underparts. Forehead is dark gray, eye patch is gray. Primaries are darker gray than other flight feathers. Forked tail, feathers are narrowly white-tipped. Alternates rapid, shallow wing beats and stiff-winged glides.
Range and Habitat
Fork-tailed Storm-Petrel: Breeds on islands from southern Alaska south to northern California. Occurs throughout the northern Pacific Ocean; rare along the California coast, more common off British Columbia and Alaska. Pelagic, only comes ashore to breed.
The Fork-tailed Storm-Petrel stores oil in its stomach. They regurgitate the oil onto predators, and sometimes onto each other during squabbles over nest sites. It is also used to feed chicks.
The single egg laid is approximately 20 percent of the female's body weight, one of the largest eggs relative to body size of all birds.
Adults don't feed the chick in bad weather. After several days without food, the chick reduces its body temperature and goes into a state of torpor in which growth nearly ceases.
They use their sense of smell to find food at sea and are often the first birds to arrive at an odor source.