Nicobar Pigeon

Caloenas is a genus of pigeons. The only living species is the Nicobar. The Nicobar Pigeon, Caloenas nicobarica, is a pigeon found on small islands and in coastal regions from the Nicobar Islands, east through the Malay Archipelago, to the Solomons and Palau. It is the only living member of the genus Caloenas.

This is a large pigeon, measuring 40 cm in length. The head is grey, like the upper neck plumage, which turns into green and copper hackles towards the breast. The breast and remiges are dark grey. The tail is very short and pure white. The rest of its plumage is metallic green. The cere of the dark bill forms a small blackish knob; the strong legs and feet are dull red. The irides are dark.

Females are slightly smaller than males; they have a smaller bill knob, shorter hackles and browner underparts. Immature birds have a black tail and lack almost all iridescence. There is hardly any variation across the birds' wide range. Even the Palau subspecies C. n. pelewensis has merely shorter neck hackles, but is otherwise almost identical.

It is not a very vocal species, giving a low-pitched repetitive call.

One or two extinct species are known: Caloenas canacorum was a large species from New Caledonia and Tonga. It is only known by subfossil remains and was probably hunted to extinction by the early settlers. The Liverpool Pigeon, another extinct species from an unknown locality, has only a slightly similarity to the Nicobar Pigeon due to its neck feathers. It might belong in this genus too despite it is not supported by all scientists. One surviving specimen exists in the Liverpool Museum.