Abstract

Mahogany gliders, Petaurus gracilis, and sugar gliders, Petaurus breviceps, were trapped in an area of open woodland in north Queensland between 1994 and 1996 to examine their population ecology and life history. This study area contained two smaller areas, one consisting of continuous habitat and the other an area of fragmented habitat adjacent to the continuous habitat. Within the continuous area, the mahogany glider had an average density of 0.24 ha^–1 whereas the sugar glider had an average density of 0.27 ha^–1. In contrast, the density of mahogany gliders in the fragmented habitat averaged only 0.16 ha^–1 whereas the density of sugar gliders was higher, at 0.46 ha^–1. Both the mahogany glider and the sugar glider showed sexual dimorphism in their weight, head length and head width. The average body weight of both species fluctuated throughout the year with no consistent pattern. The mahogany glider showed a distinct breeding season, with births being recorded between April and October, whereas the sugar glider showed no pattern, with births being recorded during all months except February and April. During the study, all adult females of both species were observed to have bred, with an average litter size of 1.55 and a natality rate of 2.09 for the mahogany glider, and an average litter size of 1.83 and a natality rate of 2.14 for the sugar glider. The sugar glider was able to raise two litters of young within a single year whereas a second litter was raised by the mahogany glider only if the first litter was lost.