This is a list of the bird species recorded in the Cook Islands. The avifauna of the Cook Islands include a total of 88 species, of which 7 are endemic and 3 have been introduced by humans.
This list's taxonomic treatment (designation and sequence of orders, families and species) and nomenclature (common and scientific names) follow the conventions of The Clements Checklist of Birds of the World , 2022 edition. The family accounts at the beginning of each heading reflect this taxonomy, as do the species counts found in each family account. Introduced and accidental species are included in the total counts for the Cook Islands.
The following tags have been used to highlight several categories. Not all species fall into one of these categories. Those that do not are commonly occurring native species.
Order: Anseriformes Family: Anatidae
Anatidae includes the ducks and most duck-like waterfowl, such as geese and swans. These birds are adapted to an aquatic existence with webbed feet, flattened bills, and feathers that are excellent at shedding water due to an oily coating.
Order: Galliformes Family: Phasianidae
The Phasianidae are a family of terrestrial birds which consists of quails, partridges, snowcocks, francolins, spurfowls, tragopans, monals, pheasants, peafowls, grouse, ptarmigan, and jungle fowls. In general, they are plump (although they vary in size) and have broad, relatively short wings.
Order: Columbiformes Family: Columbidae
Pigeons and doves are stout-bodied birds with short necks and short slender bills with a fleshy cere.
Order: Cuculiformes Family: Cuculidae
The family Cuculidae includes cuckoos, roadrunners and anis. These birds are of variable size with slender bodies, long tails and strong legs. The Old World cuckoos are brood parasites.
Order: Caprimulgiformes Family: Apodidae
Swifts are small birds which spend the majority of their lives flying. These birds have very short legs and never settle voluntarily on the ground, perching instead only on vertical surfaces. Many swifts have long swept-back wings which resemble a crescent or boomerang.
Order: Gruiformes Family: Rallidae
Rallidae is a large family of small to medium-sized birds which includes the rails, crakes, coots and gallinules. Typically they inhabit dense vegetation in damp environments near lakes, swamps or rivers. In general they are shy and secretive birds, making them difficult to observe. Most species have strong legs and long toes which are well adapted to soft uneven surfaces. They tend to have short, rounded wings and to be weak fliers.
Order: Charadriiformes Family: Charadriidae
The family Charadriidae includes the plovers, dotterels and lapwings. They are small to medium-sized birds with compact bodies, short, thick necks and long, usually pointed, wings. They are found in open country worldwide, mostly in habitats near water.
Order: Charadriiformes Family: Scolopacidae
Scolopacidae is a large diverse family of small to medium-sized shorebirds including the sandpipers, curlews, godwits, shanks, tattlers, woodcocks, snipes, dowitchers and phalaropes. The majority of these species eat small invertebrates picked out of the mud or soil. Variation in length of legs and bills enables multiple species to feed in the same habitat, particularly on the coast, without direct competition for food.
Order: Charadriiformes Family: Stercorariidae
The family Stercorariidae are, in general, medium to large birds, typically with grey or brown plumage, often with white markings on the wings. They nest on the ground in temperate and arctic regions and are long-distance migrants.
Order: Charadriiformes Family: Laridae
Laridae is a family of medium to large seabirds, the gulls, terns, and skimmers. Gulls are typically grey or white, often with black markings on the head or wings. They have stout, longish bills and webbed feet. Terns are a group of generally medium to large seabirds typically with grey or white plumage, often with black markings on the head. Most terns hunt fish by diving but some pick insects off the surface of fresh water. Terns are generally long-lived birds, with several species known to live in excess of 30 years.
Order: Phaethontiformes Family: Phaethontidae
Tropicbirds are slender white birds of tropical oceans, with exceptionally long central tail feathers. Their heads and long wings have black markings.
Order: Procellariiformes Family: Diomedeidae
The albatrosses are among the largest of flying birds, and the great albatrosses from the genus Diomedea have the largest wingspans of any extant birds.
Order: Procellariiformes Family: Oceanitidae
The southern storm-petrels are relatives of the petrels and are the smallest seabirds. They feed on planktonic crustaceans and small fish picked from the surface, typically while hovering. The flight is fluttering and sometimes bat-like.
Order: Procellariiformes Family: Hydrobatidae
Though the members of this family are similar in many respects to the southern storm-petrels, including their general appearance and habits, there are enough genetic differences to warrant their placement in a separate family.
Order: Procellariiformes Family: Procellariidae
The procellariids are the main group of medium-sized "true petrels", characterised by united nostrils with medium septum and a long outer functional primary.
Order: Suliformes Family: Fregatidae
Frigatebirds are large seabirds usually found over tropical oceans. They are large, black and white or completely black, with long wings and deeply forked tails. The males have coloured inflatable throat pouches. They do not swim or walk and cannot take off from a flat surface. Having the largest wingspan-to-body-weight ratio of any bird, they are essentially aerial, able to stay aloft for more than a week.
Order: Suliformes Family: Sulidae
The sulids comprise the gannets and boobies. Both groups are medium to large coastal seabirds that plunge-dive for fish.
Order: Pelecaniformes Family: Ardeidae
The family Ardeidae contains the bitterns, herons, and egrets. Herons and egrets are medium to large wading birds with long necks and legs. Bitterns tend to be shorter necked and more wary. Members of Ardeidae fly with their necks retracted, unlike other long-necked birds such as storks, ibises and spoonbills.
Order: Accipitriformes Family: Accipitridae
Accipitridae is a family of birds of prey, which includes hawks, eagles, kites, harriers and Old World vultures. These birds have powerful hooked beaks for tearing flesh from their prey, strong legs, powerful talons and keen eyesight.
Order: Coraciiformes Family: Alcedinidae
Kingfishers are medium-sized birds with large heads, long pointed bills, short legs and stubby tails.
Order: Psittaciformes Family: Psittaculidae
Characteristic features of parrots include a strong curved bill, an upright stance, strong legs, and clawed zygodactyl feet. Many parrots are vividly coloured, and some are multi-coloured. In size they range from 8 cm (3.1 in) to 1 m (3.3 ft) in length. Old World parrots are found from Africa east across south and southeast Asia and Oceania to Australia and New Zealand.
Order: Passeriformes Family: Monarchidae
The monarch flycatchers are small to medium-sized insectivorous passerines which hunt by flycatching.
Order: Passeriformes Family: Acrocephalidae
The members of this family are usually rather large for "warblers". Most are rather plain olivaceous brown above with much yellow to beige below. They are usually found in open woodland, reedbeds, or tall grass. The family occurs mostly in southern to western Eurasia and surroundings, but it also ranges far into the Pacific, with some species in Africa.
Order: Passeriformes Family: Sturnidae
Starlings are small to medium-sized passerine birds. Their flight is strong and direct and they are very gregarious. Their preferred habitat is fairly open country. They eat insects and fruit. Plumage is typically dark with a metallic sheen.
Order: Passeriformes Family: Estrildidae
The estrildid finches are small passerine birds of the Old World tropics and Australasia. They are gregarious and often colonial seed eaters with short thick but pointed bills. They are all similar in structure and habits, but have wide variation in plumage colours and patterns.