Cook's petrel

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

The Cook's petrel (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.[2]

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. 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.[2] 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.

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. BirdLife International (2012). "Pterodroma cookii". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
  2. 1 2 Robertson, Hugh; Barrie, Heather (1999). The Hand Guide to the Birds of New Zealand. Penguin. ISBN 978-0198508311.
  • Cook's petrel media at ARKive
  • Field Guide to the Birds of North America. National Geographic. ISBN 0-7922-6877-6. 
  • Harrison, Peter. Seabirds, an Identification Guide. ISBN 0-395-60291-2. 
  • del Hoyo, Josep (ed.). Handbook of the Birds of the World. Vol 1. ISBN 84-87334-10-5. 
  • Sibley, David Allen (2000). The Sibley Guide to Birds. New York: Knopf. p. 483. ISBN 0-679-45122-6. 

External links

Wikimedia Commons has media related to Pterodroma cookii.
Wikispecies has information related to: Pterodroma cookii


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