28-11-2016 JURONG, SINGAPORE - PINK NECKED GREEN PIGEON (Treron vernans)

The pink-necked green pigeon (Treron vernans ) is a species of bird of the pigeon and dove family, Columbidae. It is a common species of Southeast Asia, found from Myanmar and Vietnam south through to the major islands of Indonesia and the Philippines (where it is called "punay"). It is a medium-sized pigeon with predominantly green plumage; only the male has the pink neck that gives the species its name. The species lives in a wide range of forested and human-modified habitats and is particularly found in open habitats. Its diet is dominated by fruit, in particular figs. Pairs lay two eggs in a flimsy twig nest in a tree, shrub, or hedge, and work together to incubate the eggs and raise the chicks. The species is thought to be an important disperser of fruit seeds. The species has adapted well to human changes to the environment, and can be found in crowded cities as long as fruiting trees are present. It is not considered to be at risk of extinction.

The pink-necked green pigeon is a medium-sized pigeon, measuring 25 to 30 cm (9.8–11.8 in) in length and weighing around 105–160 g (3.7–5.6 oz). The species has sexually dimorphic plumage. The male has a grey head, pinkish neck and upper breast, and the rest of the breast is orange. The back is olive green and the wings are green with black primaries and yellow edging on the tertiaries which create a yellow bar across the wing in flight. The belly is yellowish with grey flanks, and the tail is grey with a black band at the end, and a chestnut uppertail coverts. The female is smaller overall, has a yellowish belly, throat and face, and greenish crown and back of the neck, although is otherwise similar to the male. The legs are pink or reddish, and the bill is white, pale blue green or grey. Juvenile birds look similar to females but are greyer above.

Pigeons in the genus Treron are unusual in the family for not having cooing calls, instead making whistling and quacking noises, but some cooing notes have been recorded for the pink-necked green pigeon, as the male makes a tri-syballic whistling call ending in a coo. It is also reported to make a rasping krrak krrak... call, but the species is generally held to not be particularly vocal, usually only calling in communal roosts and when it finds food.

The range of the pink-necked green pigeon extends from southern Myanmar, Thailand, Cambodia, and Vietnam south through the Malay Peninsula and across the Greater Sundas (and their surrounding islands), Bali, Lombok, Sumbawa, and as far east as the Moluccas as well as the Philippines. It occupies a variety of habitats, including primary forest, forest edge, secondary forest, and coastal mangroves. It favours more open environments and where it is found in association with denser forest it is typically on the edges. It is also readily found in human dominated environments such as gardens, plantations and farmland. It is more common in lowlands and close to the coast, but can be found up to 300 m (980 ft) in the Philippines, 750 m (2,460 ft) in Borneo and 1,200 m (3,900 ft) in Sulawesi. The species is recorded as non-migratory by the Handbook of the Birds of the World, but other sources have described it as making local movements. A related species, the thick-billed green pigeon, covers vast distances in search of fruit, and it is likely that the pink-necked green pigeon has a similar behaviour.

After the main island of Krakatoa was obliterated in a volcanic eruption in 1883, leaving a handful of smaller islands, the pink-necked pigeon was observed on the first bird survey of these remnants. The survey was conducted in 1908, and at the time the pigeon was the only obligate frugivore (meaning it ate mostly fruit, as opposed to as part of a wider diet or opportunistically) that had established itself on the islands. Within the archipelago it was able to colonise Anak Krakatau, a volcano that emerged from the sea from the caldera in 1927, within 36 years of the new island suffering a large eruption in 1952. The delay between the island settling down and colonisation was likely due to the time taken for figs to become established on the island and begin fruiting. It later became extinct on that island, due to a small population and predation. The species has recently expanded its range, having colonised Flores at some time since 2000.