Nevafou Megapode

Polynesian megapodes are thought to be primarily monogamous, with pairs defending a shared territory, although roosting in different trees at night. Duets frequently performed by pairs may have a territorial function, but also indicate long-lasting pair bonds, serving to announce, form and strengthen those bonds. Polynesian megapodes nest in burrows and provide no parental care after the egg has been laid, so rely on thermally heated soil on volcanic islands to incubate the egg. Females produce eggs year-round, with one large egg laid at a time in communal burrows that are used repeatedly over decades. Between 12 and 16 eggs are produced per year. Chicks hatch underground after incubating for 50 to 80 days, and then dig themselves out (4). Since offspring must live independently from their parents immediately after hatching and be able to fend for themselves, they hatch at a large and advanced stage of development (4) and can fly immediately after they emerge from the ground (6). The Polynesian megapode forages for food in leaf-litter and top soil, feeding mainly on insects and worms, but also taking small reptiles, seeds and small fruit (5). Mated pairs forage together and females frequently feed on food items uncovered by the male (4).

The Polynesian megapode is legally protected, although in practice there is no real enforcement, and egg-collecting urgently needs to be brought under control. From 1991 to 1993, 60 eggs were introduced on Late Island, buried at volcanically heated sites, and 35 eggs and chicks were transferred to Fonualei, both islands being uninhabited, rarely visited, and with appropriate egg-laying conditions. While surveys suggest the reintroduction on Late failed, the now established population on Fonualei is a fantastic conservation success story, and provides new hope for the future of this rare bird. It has been advocated that Fonualei should be given Reserve status, and if achieved, this volcanic island may prove to be the safe refuge that ensures the Polynesian megapodes long-term survival (5). However, there is always the threat of eruption, which could potentially destroy the Fonualei population completely, and thus this species' restricted range leaves it in an extremely vulnerable position.

Megapodes are so named because of their unusually large feet (3). This small megapode has a mostly brown-grey plumage, paler on the head and neck and browner on the back and wings, and yellow-orange legs and beak (4). Feathers of the face and throat are sparse, allowing the red skin beneath to show through, and there is a short, rounded crest on the back of the head. The duet between male and female pairs consists of a three-part whistle, kway-kwee-krrrr, from the male and a krrrr sound from the female (5).

Inhabits broadleaved forest ranging from secondary to mature. As this bird uses the heat of hot volcanic ash to incubate its eggs, its nesting sites are confined to areas of loose soil close to volcanic vents, in forest, in open ash, or on beaches of crater lakes (5).

The Polynesian megapode naturally occurs on the island of Niuafo'ou (35 km²) (2), and a reintroduced population exists on Fonualei, both in the Kingdom of Tonga, South Pacific (5).

Classified as Endangered on the IUCN Red List 2006 (1).

The Polynesian megapode occupies a precarious existence, being restricted to just two tiny islands, with the Niuafo'ou population declining due to over-harvesting and predation. All nesting sites on Niuafo'ou are harvested by the local human population, with at least 50 % of all eggs being collected or destroyed. Adults are also hunted on a smaller scale, and both adults and chicks suffer from predation by feral cats and dogs. Pigs may pose an additional threat by competing for food. Fortunately, Fonualei is uninhabited and little-visited so the population there is relatively safe from the threats of hunting and human disturbance (5). In 2003 an incredible 300 to 500 birds were estimated to exist on the island, a significant increase from the 35 eggs and chicks that were introduced in 1993. Following this remarkable discovery, which effectively doubled the total known population of Polynesian megapode, the species was downlisted from Critically Endangered to Endangered on the IUCN Red List of Threatened Species (5) (3).