Green-naped Pheasant Pigeon

The green-naped pheasant pigeon is a subspecies of the pheasant pigeon, a large terrestrial pigeon of New Guinea's primary rainforests, found in western New Guinea and on Batanta and Waigeo Islands. Like a small pheasant, it has a laterally compressed tail and rounded wings, with a glossy black head and underparts and a green nape. Highly secretive, it forages on the forest floor for seeds and fallen fruit and nests on the ground beneath trees and bushes. A pair lays a single egg, incubated for around four weeks by both adults, who then feed the chick regurgitated crop milk. It avoids human settlements, so little is known about its behaviour.

About the green-naped pheasant pigeon

The green-naped pheasant pigeon is a large, ground-dwelling pigeon of western New Guinea and the nearby islands of Batanta and Waigeo. It is the nominate form of the pheasant pigeon, the sole member of the genus Otidiphaps when its four forms are treated as one species, and it walks the floor of primary rainforest the way a pheasant would.

Its scientific name is Otidiphaps nobilis. The genus name points to a likeness with the bustards (family Otididae), while the common name reflects its pheasant-like life on the forest floor. Some authorities treat the four forms of pheasant pigeon as subspecies of one species; others, including the IUCN, treat them as four separate species. The green-naped bird is the one that carries the original name, nobilis.

From a distance it hardly looks like a pigeon at all. It stands on long legs and holds its tail folded and arched like a roof, the way a pheasant does. The tail is laterally compressed and has 20 to 22 feathers, and the wings are short and rounded, with feathers that are unusually small and round for a pigeon of this size. Only the head is a typical pigeon head. Body length reaches about 50 cm (20 in), and measured birds of the white-naped form averaged 475 g (1.0 lb) for females and 508 g (1.1 lb) for males.

The color is rich and glossy. The head is shiny greenish-black and blue, with a small crest swept backward. In the green-naped form the hind neck is bronze-green to turquoise, with a bronze patch below it. The neck, breast, and belly are dark green, the back and wing coverts are reddish-brown, and the feathers above the tail are dark blue. The bill is bright red and the eye is orange-red. Males and females look alike.

These anatomical quirks set pheasant pigeons apart from other pigeons, and their relationship to the rest of the pigeon family is uncertain, although they clearly belong to the pigeon order. They are placed in their own subfamily, Otidiphabinae. One explanation offered for the pheasant-like body is that New Guinea has no native game birds of the chicken and pheasant order, leaving that role open.

Behavior and diet

The pheasant pigeon fills the ecological niche of a partridge or small pheasant in New Guinea's forests. Its larger relatives, the crowned pigeons of the genus Goura, such as the Victoria crowned pigeon, play the part of larger pheasants, grouse, or turkeys. It spends its life on the ground and rarely flies, flying up only to sleep on low branches.

It is a highly secretive bird that avoids people and settlements. So little is known from the wild that much of what has been described about its behavior comes from birds kept in human care. Courtship display, for example, has been observed and recorded in captive birds.

Food is taken from the forest floor. It eats fallen fruit and seeds, and current knowledge suggests berries, insects, and insect larvae make up much of its diet.

Pheasant pigeons have a varied voice. Calls include a drilling sound, an ordinary pigeon coo, and a loud "wu-huwoooooa" that rises and falls before trailing off. Both sexes give frequent contact calls that carry a long way, and one call is described as a moaning "c-o-o-o-o."

Breeding is slow. The nest is built on the ground beneath trees and bushes or low in the branches, and the female lays just one egg. In the white-naped form the egg is white and measures about 4.4 by 3.1 cm (1.7 by 1.2 in). Both parents incubate it for around four weeks, about 28 days, and both care for the chick. Like most pigeons, they feed their young on regurgitated crop milk. The chick can fly at 28 to 30 days old.

The species is long-lived in human care, with recorded life expectancy of up to 26 years. Breeding has been recorded in white-naped birds as old as 13.4 years for a female and 19.9 years for a male, and the generation length is about 6.6 to 6.8 years.

Range and habitat

The pheasant pigeon as a whole is found only in New Guinea and nearby islands. The green-naped form lives in western New Guinea and on the islands of Batanta and Waigeo. The grey-naped form occupies eastern and southeastern New Guinea, the white-naped form lives on the Aru Islands, and the black-naped form is restricted to Fergusson Island.

It is a bird of primary rainforest, the original, uncut forest. It ranges mostly over hilly and lower mountain country, using montane forest up to about 1,600 m (5,250 ft), but it also turns up in the lowlands. Because it is tied to undisturbed forest and keeps away from people, it is rarely seen.

Green-naped vs other pheasant pigeons

The four forms of pheasant pigeon look almost identical except for one patch of color on the back of the neck, and they are sometimes split into four species. Their conservation status differs sharply.

The forms also differ in whether a small crest is present. The black-naped bird was known only from specimens collected in 1882 and 1896 and was long feared extinct, until a trail camera recorded it on Fergusson Island in September 2022.

Conservation status

The IUCN treats the green-naped pheasant pigeon as a species in its own right, Otidiphaps nobilis in the narrow sense, and lists it as Least Concern on the IUCN Red List, based on a 2024 BirdLife International assessment. The grey-naped form is also not considered threatened. The white-naped form is rated Vulnerable, and the black-naped form is Critically Endangered.

The pheasant pigeon as a whole is believed to be declining slowly as rainforest is cleared for logging and farmland. Because it depends on primary forest and is unique within the pigeon family, it is considered a genus that needs further study and monitoring.