White-chinned Petrel
White-chinned Petrel ( Procellaria aequinoctialis )
The White-chinned Petrel ( Procellaria aequinoctialis ) is a monotypic species of the family of the petrels. It is a large, powerfully built Petrel, which occurs in the southern hemisphere. The was threatening factors for this species belongs mainly longline fishery.
The IUCN classifies the White-chinned Petrel as endangered ( vulnerable ), because it assumes a currently taking place, strong population decline. On some of the breeding islands, the number of occupied nests was in a period of twenty years by 28 percent, and in the Antarctic Prydz Bay, the number of observed White-chinned petrels 1981-1993 to 86 percent. Overall, the stock is still estimated at 3.5 million mature individuals.
Appearance
The White-chinned Petrel reaches a body length of 51-58 inches. The wing length is 35.5 to 41.5 inches and the wingspan 134-147 cm. The weight of the White-chinned petrels varies from 1.28 to 1.39 kg. Males tend to have slightly longer wings than females and a wider beak.
The White-chinned Petrel is predominantly black feathered brown. He only has a small white spot on chin, whose size varies individually and is not seen in most field observations. The pale yellow beak contrasts strikingly with the dark plumage and is very strong. The feet are black. The primaries are on the bottom a little brighter. The plumage of the young birds is not very different from that of the adult birds.
Confusion possibilities especially with the Westland petrel, Parkinson's Petrel and the Blassfuß shearwater.
Dissemination
The White-chinned Petrel breeds on the Falkland Islands, South Georgia, the Prince Edward Islands, Crozet Islands, Kerguelen, the Auckland Islands, Campbell Islands and the Antipodes Islands. Outside the breeding season it is observed on the coasts of South America until 6 degrees south latitude as well as in Africa to 15 degrees south latitude. The main breeding sites are located on South Georgia. On the Falkland Islands breed only about 1,000 to 5,000 breeding pairs.
Way of life
The White-chinned Petrel lives predominantly cephalopods, fish and crustaceans. He captures his food occasionally fall diving from a height of up to 13 meters. Outside the breeding season, fish plays a larger role in his diet than during the breeding season of the case. He is occasionally observed individually in search of food, but adheres more often in loose flocks, and is then associated with other seabirds. Occasionally follows the White-chinned Petrel on its foraging also ships.
White-chinned petrels nest in loose colonies. The entrance to their nests they defend it vigorously. For the breeding self-dug burrows are used that are dug on gently sloping hills. The nest boxes having a length of one to two meters. At the end we find the nest hollow, which is designed with little material.
On the Falklands reverse the White-chinned petrels in late September in the breeding colonies back. The nest consists of a single egg, which is laid on the Falkland Islands in late October or early November. The incubation period is 57 to 62 days. The young birds fledge after 87-106 days. It is raised only one juvenile per year. Both parents birds are equally involved in the breeding and rearing of the young bird.
This great storm bird is introduced to the breeding islands rats slightly less threatened than smaller, nest boxes -build - seabirds. However, feral cats can develop into a threatening factor consisted in the breeding colonies.