Nicobar Pigeon
Caloenas nicobarica (Linnaeus, 1758)
Range: Nicobar
and Andaman Islands, Southeast Asia, Philippines, Indonesia, New Guinea,
Solomon Islands, Palau. Most abundant on
the smallest, least-disturbed islands.
Habitat: Mature lowland and foothill forests, mangroves,
up to 700 meters elevation
Diet: Seeds, Fallen Fruits, Invertebrates
Social Grouping: Flocks of up to 85 birds, form larger colonies for breeding
Reproduction: Courtship consists of male cooing loudly and displaying in front of the female with a series of bows. May go on for days. After courtship, male will select a nest site and gather nesting material to present to the female, who then arrange the items into a nest. Pairs are monogamous, usually for life. Nest is a crude platform of twigs; sometimes several nests may be constructed in the same tree. Females lay 1-2 elliptical eggs, weight with a faint bluish tint. Both parents share the incubation duties for 28-30 days. Chicks are altricial, so parents continue to sit on them until 10 days of age, when the feathers begin to grow in. Chicks fledge at 30-60 days old
Lifespan: 10-15 Years
- Body length 38-43 centimeters, weight 600 grams, heavily built with a relatively small head. Females are slightly shorter and heavier than males
- Dark, iridescent green color with a grey head and a short white tail. Most notable traits are the long, pointed, hair-like feathers (hackles) around the neck with green, blue, and copper-colored overtones. Juveniles lack the white tail. Bill is black, large feet are red. The iris is white in adult females, but brown in males and sub-adult females
- Males have a small black knob at the base of the bill, near the forehead. Males also have longer hackles, tend to have longer necks than the females.
- Most active in the early morning and at twilight. Show little aggression towards each other or other birds. Spend most of their time on the ground, roost together at night. Fly in almost single-file columns. Possible that the white tail feathers, which are very prominent in flight, serve as a sort of taillight to help keep flocks together when crossing the sea in dim light
- Typically seen foraging on the ground. Strong, hooked beak is capable of cracking open nuts, which they grind up using their muscular gizzard
- Like other pigeons and doves, drinks by submerging its beak and sucking, rather than by throwing back beakfuls of water as many other birds do
- Very vocal, giving low-pitched repetitive call, may grunt like a pig if threatened
- Like other pigeons, Nicobar pigeons first feed their chicks “crop milk,” a rich fluid regurgitated by the female. Gradually weaned onto solid foods
- Two subspecies: the nominate, found over most of the range, and C. n. pelewensis, found only on Palau, which differs mostly in having shorter neck hackles
- Genetic studies conducted by Oxford University Museum of Natural History suggest that the Nicobar pigeon is the closest living relative to the dodo and the Rodriguez solitaire. Closest living relatives of the Nicobar pigeon are the crowned pigeons (Goura)
- Has a wide geographic range, but still threatened by hunting (primarily for food, but also for the gizzard stones, used in jewelry), live capture for the pet trade, habitat destruction, and predation from introduced mammals (primarily rats and domestic cats) to their nesting islands
- One of the most important breeding colonies, Batti Malv on the Nicobr Islands, was almost wiped out during the 2004 Indian Ocean tsunami
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