Nicobar Megapode - Behaviour and Ecology

Behaviour and Ecology

The Nicobar Megapodes are secretive in their habits. During the day, they move around in thick jungle adjacent to the sea shore. In the dark, they venture out on the shore. They move in pairs or small groups. The group may consist of birds of various ages including just hatched ones. When disturbed, they prefer to escape by running but take to wings when pressed. The group keeps in touch with cackling calls. Pairs indulge in duet calling and maintain territories. Many species in the genus are said to be monogamous, but the Nicobar Megapode has been found to form temporary pair bonds.

The Nicobar Megapode has an omnivorous diet. They forage mainly by scratching and raking debris on the ground using their feet. A study in Great Nicobar found from an examination of their stomach that their food was mainly made up of the seeds of Macaranga peltata followed by insects, snails, crustaceans and reptiles. They also ingest grit to aid in digestion and have been observed to drink rainwater.

Like other megapodes in the genus, they build a large mound nest. The mounds are generally built close to the coast. These mounds are constructed with coral sand containing minute shells and plant materials, such as leaves, twigs, and other debris. Mounds are built on open grounds or against a fallen log or tree stump, or against a large living tree. Generally mounds are reused, by scraping the top layer of sand, piling up fresh vegetable matter and then raking up a new layer of sand. A mound may be shared by a pair and their progeny. New mounds are built either by digging a pit or piling up soil and plant materials against the stump or fallen log. The mound size varies considerably (less than 1 cu. m to more than 10 cu. m), though this does not have an effect on the hatching success. The eggs are elongate elliptical in shape and at a sixth of the weight of the bird, relatively large. Peak egg laying was observed from February to May. The eggs are pinkish without markings or gloss, and loses its colour with age. The egg is laid on the mound and the parent digs a hole to bury it within and covers it up with plant material and soil. On an average, 4 to 5 eggs are laid in a mound but up to 10 have been noted, the eggs being in very different stages of development. A single mound may be used by more than one pair of birds. Microbial activity is the primary source of heat within mounds for incubation. The incubation period is approximately 70–80 days varying based on the incubation temperature.

The young birds hatch fully feathered, and as soon as the feathers dry up, can fly. They do not need any parental care and join the group immediately. In the 1900s, eggs taken to Calcutta zoo hatched and the chicks, reared on a diet of termites, grew very tame.