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).