These nocturnal animals rest during the day in communal roosts (known as camps) of up to hundreds of thousands of individuals (in the Northern Territory, roosts rarely exceed 30,000 animals), which they sometimes share with the grey-headed flying fox (Pteropus poliocephalus) or little red flying fox (Pteropus scapulatus ). Temperature is regulated by the bats wrapping their wings tightly around themselves if cold or wet, and flapping their outstretched wings when hot (2). Come sunset, thousands of bats set off to feed, using sight and smell (7) to find the nectar, fruit and blossom of trees such as eucalypts, paperbarks and turpentine trees (2) (6). These bats utilise different resources depending upon the time of year, and may travel up to 50 kilometres a night in search of food (2) (6) (9). When native foods are scarce, particularly during drought, the bats take introduced or commercial fruits such as mangoes (5). Leaves are also eaten by chewing them to a pulp, swallowing the juice and expelling the pulp, and fig fruits are also eaten in this way (6).
During the mating season from February through to April (10), depending on the region, males establish and defend a small territory of about one metre along a branch, where they spend time grooming and displaying their genitalia (2) (6). Young are born between October and March in southern Australia (2) (10) or July and August in northern Australia, with birth peaks at maximum local plant productivity (2), when lots of trees are in bloom and there's plenty of fruit to feed upon (7). A single young is born and carried by its mother for the first month of life, after which it is left behind in the roost when the mother is off feeding (2). At two to three months old the pup can fly and will begin to follow its mother at night to forage and learn crucial life skills, gaining independence three months later (2) (6).