Pink-necked Green Pigeon

The pink-necked green pigeon is primarily a frugivore, taking a range of fruits, particularly figs (Ficus). Fruit of other trees are taken as well, including Glochidion, Breynia, Vitex, Macaranga, Muntingia, Melastoma, Oncosperma and Bridelia. Shoots, buds and seeds are also taken, but much less commonly so, often by quite a substantial margin. In one study of the frugivores of Sulawesi 55 observations were made of this species feeding and every one was of it eating fruit, mostly figs. The species feeds in the mid-canopy of the forest and rarely feeds in the understory or on the ground. It is described as being agile when clinging on fine branches to reach fruits at the end. Like other members of the genus Treron, the gizzard is muscular and contains grit, which is used to grind and digest seeds inside fruit. Studies of closely related species have found that not every individual has grit, and it is likely the same is true of this species. It is social, feeding in small groups or, where an abundant source of food is found, quite large flocks of up to 70 birds. The species also roosts communally, and can form roosting flocks of hundreds of birds. There is no defined breeding season and it has been recorded breeding all year across its range, except in February. The task of building the nest is divided by sex, with the male being responsible for collecting the nesting material and the female building it. The nest itself is a simple and flimsy platform of twigs and finer material. Two eggs are laid, which are white and measure 26.8 mm–28.9 mm × 20.3 mm–21.8 mm (1.06 in–1.14 in × 0.80 in–0.86 in). The nest is placed in a tree, shrub or hedge, and can be quite close to the ground, ranging from 1 to 10 m (3.3–32.8 ft). The breeding biology of this species is virtually unknown, with only a single breeding report from Singapore. In that report, the pair shared incubation duties, with the male incubating during the day and the female at night, with the incubation time being 17 days. On hatching the chicks are brooded continuously for the first few days of life, as with incubation the male broods during the day and the female at night. Chicks are near-naked and have brown skin with a few white pin feathers on hatching. Chicks leave the nest 10 days after hatching, but remain in the nesting area for a few days after hatching, and continue to be fed by their parents.

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.

Not globally threatened.