Petrello di Cook

Tassonomia

Nome scientifico

Pterodroma cookii

Autorità

(Gray, GR, 1843)

Ordine

Procellariformi

Famiglia

Procellaridi

Genere

Pterodroma

Areale e habitat

Cook's petrel breeds only in New Zealand on three small islands: Little Barrier Island, Great Barrier Island, and Codfish Island. The breeding season is the southern summer, October–May. It nests in burrows and rock crevices, preferring sites on thickly forested ridges. Its call is a three-part kek, kek, kek. The species was formerly more numerous; the current population estimate is 1,258,000 and declining. It is classified as vulnerable because it breeds on only three small islands. While Little Barrier Island's population remains stable, the other two populations are decreasing. On Great Barrier Island, introduced pigs, dogs, rats and cats attack nests and burrows, as do native weka (a flightless rail), preying on eggs and nestlings and reducing the population from an estimated 20,000 to 100[citation needed]. Fossils show that prior to the arrival of humans to New Zealand, Cook's petrel used to breed on the mainland New Zealand North and South Islands.<p>Cook's petrel migrates to the Pacific Ocean from New Zealand when it is not breeding. It has sometimes been seen off the west coast of the United States and off the west coast of tropical South America.

Areale riproduttivo

PO : Great and Little Barrier is. (off ne North I.) and Codfish I. (=Whenua Hou, nw of Stewart I.; New Zealand)

Areale non riproduttivo

to Tasman Sea, off se Australia and ne to se Pacific Ocean off Aleutian Is. and w Pacific coast from nw Mexico to Chile

Migrazione

Complete migrants

Conservazione

Tendenza della popolazione

rising