christmas island frigatebird

The adult has black plumage, deeply forked tail and long, hooked bill. The adult male has blackish-brown plumage overall, with green to bluish-green gloss on the blacker head, and on neck, mantle and scapulars. On the upperwing, there is a broad, pale brownish diagonal panel formed by paler secondary coverts. The forked tail is blackish. On the underparts, we can see a conspicuous white patch on belly, but it does not reach vent or axillaries, although some males may show some few white feathers on outer axillary area. The head is black with red gular pouch becoming inflated during the breeding season, but much duller and reduced outside breeding. The long, hooked bill is bluish-grey. The eyes are dark brown, surrounded by narrow blackish eyering. Legs and feet are slaty grey. The female is duller, with only little or no gloss on the upperparts. The white patch of belly is larger, extending from most of breast to rear belly, and to central axillary area. The collar on the neck sides contrasts with the black head. The bare parts including bill, gular pouch, eyering, legs and feet are pale pink. The juvenile has whitish head, nape and upper breast, with strong orange to rusty tinge. It has dark brown upperparts with pale-edged feathers on mantle and scapulars, blacker flight feathers and broad, pale brown to whitish wing panel formed by the lesser secondary coverts. On the underparts, breast sides and narrow pectoral band are dark brown. The white patch of belly extends to central flanks and to central axillaries. The bare parts including eyering, bill, legs and feet are pale bluish-grey to pale pink. The young female becomes progressively whiter on the lower breast until reaching the adult plumage. The young male has mostly blotchy neck and breast, and appears as intermediate between male and female.

The Christmas Frigatebird spends most of its time at sea, coming to land for roosting and breeding. They often roost communally with other Fregatidae species, perching at least at 3 metres above the ground for easier landing and take-off. This species breeds in the low, dry forest of the island, mostly in the outer part, in tall trees such as Indian Almond trees (Terminalia catappa) and Ficus.

Mainly Fish,
Frigatebirds are known for using kleptoparasitism to obtain food from other seabirds. They harass them until they regurgitate their preys.

The Christmas Frigatebird is vocal at breeding colonies. The displaying male is particularly noisy. The typical sounds produced by these birds are twittering, rattling, drumming (when the gular pouch is inflated) and whinnying. They also perform bill-clattering. The vibrating mandibles of a courting male against the inflated pouch used as a sound box, are very noisy. At nest, they give nasal, plaintive calls "kyeah… kyeah… kyeah".

The Christmas frigatebird (Fregata andrewsi) or Christmas Island frigatebird is a seabird of the frigatebird family Fregatidae which is an endemic breeder to Christmas Island in the Indian Ocean. The Christmas frigatebird is a large lightly built seabird with brownish-black plumage long narrow wings and a deeply forked tail. It has a wingspan of around 2.15 m (7.1 ft). The male has an egg shaped white patch on his belly and a striking red gular sac which he inflates to attract a mate. The female is slightly larger than the male and has a white breast and belly. They feed on fish taken in flight from the ocean's surface (mostly flying fish) and sometimes indulge in kleptoparasitism harassing other birds to force them to regurgitate their food. The species is listed as critically endangered by the International Union for Conservation of Nature. The Christmas frigatebird was once considered to belong to the species Fregata aquila but in 1914 the Australian ornithologist Gregory Mathews proposed that the Christmas frigatebird should be considered as a separate species with the binomial name Fregata andrewsi in honour of the English paleontogist Charles Andrews. Of the four other species within the genus Fregata genetic analysis has shown that the Christmas frigatebird is most closely related to the great frigatebird. The Christmas frigatebird measures 89&ndash100 cm (35&ndash39 in) in length has a wingspan of 205&ndash230 cm (81&ndash91 in) and weighs around 1550 g (3.42 lb). The adult male of this species is easily identified since he is all black except for a white belly patch. Other plumages resemble those of the smaller lesser frigatebird but have whiter bellies and longer white underwing spurs.