Yellow-bellied Glider

Description: The largest of the petaurid gliding possums. Its upper parts are generally brownish-grey (sometimes a rich brown) with a distinct black stripe, and yellow or cream underneath. Apart from its larger size this species is easily recognised by its colour and the fact that its fifth finger is longer than its fourth. The most vocal of the gliding possums, its calls are loud and frequent.

Distribution: Widespread but patchy from north Queensland down the east coast through New South Wales to south-eastern South Australia. Inhabits forests dominated by mature tall eucalypts in temperate and subtropical eastern Australia. At the edges of its distribution are isolated populations in north Queensland and also near the Victorian/South Australian border.

Reproduction: Females give birth between August and October in Victoria, predominantly between February and April in southern New South Wales and June to August in north Queensland. The female normally produces one young per year, although there is a record of twins. The young remains with its parents until it is 18–24 months of age.

Diet: Plant and insect exudates are its main food items, supplemented with invertebrates. It also extracts sap from different species of Eucalyptus and nectar from various genera of trees including Eucalyptus, Corymbia, Melaleuca, Banksia, and in north Queensland, Melicope and Buckinghamia. Honeydew and lerps from invertebrates as well as manna are also eaten.

Sap from different species of Eucalyptus are generally obtained by cutting V-shaped notches into the trunks of a very small number of trees, referred to as sap-site trees. In north Queensland the Red Mahogany (Eucalyptus resinifera) is the only tree species utilised for sap and is an important element within their habitat.

Ecology: Nests in hollows within trees in small family groups of two to more than four adults and their offspring. Their social organisation is flexible and appears to vary according to local resource abundance. Some populations are socially and genetically monogamous, while others can be either monogamous or polygynous. The home ranges of different groups are very large and show minimal overlap. They range in size from approximately 30 hectares to over 65 hectares.

The density is low, ranging from 0.05–0.14 animals per hectare. The Yellow-bellied Glider has some 17 different calls including loud shrieks, long gurgling calls and soft buccal clicks. The most frequent calls serve to advertise its territory. As is in all petaurids, scent marking plays a major role in maintaining group cohesion.

Status: Least Concern.

The northern, undescribed population is listed as vulnerable and the population in South Australia is considered endangered. A population viability analysis of the species suggested that at least 150 glider groups are needed to support viable populations, requiring an area of a minimum of 9750 hectares where all habitat is suitable, but as only 28–54 per cent of the habitat at some locations may be suitable, 18 000–35 000 hectares is required.