The Ecology of Fruit Pigeons in Tropical Northern Queensland

A 3-year study of seven species of fruit pigeons in the lowland tropical rain forest of northern Queensland examined the effects of forest phenology upon pigeon populations and breeding and the means whereby these seven species coexisted. Because of the asynchrony of the fruiting seasons of individual plant species there was fruit available all the year round, and the diet of each species of pigeon changed according to the species of fruit available and the feeding selectivity of the birds. Fruiting was seasonal, with the dry season (July- November)being the time of maximum fruit abundance, and the late wet season (February-April)a time of relative shortage. There were also between-year differences in fruiting, 1970 and 1972 being good years with heavy dry-season fruit production whereas 1971 was a time of general crop failure. Pigeons were most numerous and bred during the dry-season period. Coexistence was facilitated by each species feeding in a different suite of plant species, by nomadism and by migration. At any one time two or three species were common and the rest rare or absent. Ecological overlap between these species, as measured by the percentage of foraging observations in common, varied from c. 7