Cook's Petrel

Pterodroma cookii




Petrels and Shearwaters (Procellariidae)

Code 4


Code 6



Egg Color:


Number of Eggs:


Incubation Days:

45 - 55

Egg Incubator:

Both sexes

Nest Location:

On high forested slope.

Nest Material:

No material added to nest.





Cook's Petrel: Small petrel with slate-gray back and upperwings marked by a distinctive black M pattern. Underparts and underwings are white. Face is white with small, dark eye patch. Wings are long and slender. Tail is gray with black-tipped central feathers and white edges. Iris black-brown; black bill, legs and base of toes are blue to pale violet with dull pink to dark yellow webs; rest of toes black-gray. Sexes are similar. Juvenile has paler feather tips on upperparts.

Range and Habitat

Cook's Petrel: Breeds only in New Zealand, on Little Barrier, Great Barrier and Codfish Islands. Migrate to the Pacific coast of South America, and across the equator to the east Pacific Ocean. Generally found over temperate and subtropical waters. Pelagic, as they rarely occur near land except when breeding on offshore islands, forested ridges and steep slopes.

Breeding and Nesting

Cook's Petrel: The breeding season extends from October to April. One white egg is laid on a high, forested island slope on bare soil, or in a burrow dug or cleaned out by both parents. A few may nest in crevices. Incubation ranges from 45 to 55 days and is carried out by both parents. Chicks fledge after 88 days.

Foraging and Feeding

Cook's Petrel: These petrels feed mainly on small squid but also eat some fish and crustaceans. They skim the water and snatch prey from the surface. The type of foods eaten suggests most of the feeding is done at night, although activity loggers showed that birds were also active by day during the breeding season.


Cook's Petrel: On breeding grounds gives a rapidly repeated "ti-ti-ti" or "whik-kek-kek."

Similar Species

Cook's Petrel: Buller's Shearwater is larger, has back head, dark wedge-shaped tail, more contrasting M on back, and lacks dark ear patch.


Belly, undertail coverts, chest, flanks, and foreneck.

Back, rump, hindneck, wings, and crown.
The front part of the head consisting of the bill, eyes, cheeks and chin.
The pelagic is a type of bird whose habitat is on the open ocean rather than in a coastal region or on inland bodies of water (lakes, rivers). An example of a pelagic bird is the blacklegged kittiwake.
Parts of a Standing bird X
Head Feathers and Markings X
Parts of a Flying bird X