Jump to content

Cook's petrel

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Tom.Reding (talk | contribs) at 22:45, 8 November 2016 (top: Fix Category:CS1 maint: Uses authors parameter: vauthors/veditors or enumerate multiple authors/editors/assessors; WP:GenFixes on, enum'd 1 author/editor WL, using AWB). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

Cook's petrel
Scientific classification
Kingdom:
Phylum:
Class:
Order:
Family:
Genus:
Species:
P. cookii
Binomial name
Pterodroma cookii
(G.R. Gray, 1843)

The Cook's petrel (blue-footed petrel[2]) (Pterodroma cookii), is a Procellariform seabird. It is a member of the gadfly petrels and part of the subgroup known as Cookilaria petrels, which includes the very similar Stejneger's petrel.

Morphology

One of the smallest petrels, Cook's petrel is typically 25–30 cm (9.8–11.8 in) in length with a 65–66 cm (26–26 in) wingspan and a weight of around 200 g (7.1 oz). Its colouration is typical of gadfly petrels: pale grey upperparts with a dark grey "M" on the wings and white underparts.[3]

The bill is long and black with tubular nostrils on both sides. As in all members of the order Procellariiformes, this nostril configuration enables an exceptionally acute sense of smell, which the birds use to locate food and nest sites in the dark.

Habitat

Cook's petrel photographed in Hauraki Gulf, New Zealand

Cook's petrel feeds mostly on fish and squid, with some crustaceans taken[citation needed]. The species is highly pelagic except when nesting.

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.[3] It nests in burrows and rock crevices, preferring sites on thickly forested ridges. 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].

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.

References

  1. ^ Template:IUCN
  2. ^ http://nzbirdsonline.org.nz/species/cooks-petrel
  3. ^ a b Robertson, Hugh; Barrie, Heather (1999). The Hand Guide to the Birds of New Zealand. Penguin. ISBN 978-0198508311.