Feeding behaviour of the yellow-bellied glider (Petaurus australis) at thewestern edge of its range

This study provides the first assessment of the diet of the yellow-bellied glider (Petaurus australis) in the south-west portion of its range near the Victorian-South Australian border. Examining its diet in this region is vi ewed as being fundamental to understanding the ecological requirements of t he species. Observations were conducted over a five-year period on gliders from five distinct groups. Sap was the most important food item throughout the year and accounted for 83% of 407 feeding observations. Each group of g liders used up to 21 different trees for sap, but during any sample period only 1-8 trees were used. This represents a vastly different pattern of use of sap trees to that described in any earlier study. Some trees were visit ed more often than others, and these tended to be heavily scarred, indicati ng use over many years. Other food types were arthropods and honeydew and, to a lesser extent, nectar. This study also revealed that the yellow-bellie d glider is not dependent on a diversity of tree species nor on a winter-fl owering species. We provide a review of the diet of the yellow-bellied glid er throughout its range. This shows that the yellow-bellied glider is relia nt on sap as a food resource but particularly so at both ends of its geogra phic range. The reason for this is unclear, but there is definitely a need for further study of sap-flow patterns in eucalypts.