Four species of Pteropus occur on the Australian mainland: conspicillatus, gouldi, polio-cephalus, scapulatus. They are found along the north and east coasts, rarely, with the exception of scapulatus, outside the coastal belt. The daytime congregations may number hundreds of thousands. The average interval between these "camps" is 15-20 miles in north and central Queensland and 30-40 in south Queensland and New South Wales. The chief item of diet is the blossom of Eucalyptus spp. Fruit, wild and cultivated, is of secondary importance. The bats are attacked by various predacious birds and reptiles, the mortality falling chiefly among the young. One young one is normally produced each year. The period of gestation is apparently 5-6 months. The breeding seasons of P. conspicillatus, gouldi, and poliocephalus are roughly coincident, though slightly earlier in the more tropical species. That of scapulatus is reversed. All the species are migratory. The migrations of poliocephalus are very regular, the animals moving north in winter; those of scapulatus are rather irregular, the greatest movements being caused by drought conditions in north and central Queensland. An abnormal migration of the latter species occurred in 1926, with serious results economically. The numbers of fruit bats have decreased noticeably as a result of closer settlement, particularly in south Queensland and New South Wales.