The Squirrel Glider is a medium-sized arboreal (tree-dwelling) marsupial, with a distribution ranging from northern Victoria, through the eastern half of New South Wales and Queensland, to the base of Cape York in northern Queensland. Throughout much of this range, the species is considered rare, particularly so in remnant woodland and riverine forests that are a precious yet diminishing natural feature of our inland rural landscapes.

Squirrel Gliders usually live in small family groups, comprising one adult male, one or more adult females and their associated offspring of that season. Very occasionally, one or more young males may also be associated with a group of up to ten animals, including four to five adult animals. Family groups occupy discrete territories, which range in size depending upon habitat quality.

An important component of Squirrel Glider habitat is the presence of large, old, hollow-bearing trees. Within the protection of these trees, gliders den in bowl-shaped, leaf-lined nests. Entrance diameters to hollows containing nests are typically narrow fitting, being just large enough to allow access to gliders but prevent intrusion of larger predators. Where such large trees are absent, Squirrel Gliders are also known to nest in holes in tree stumps, particularly where coppice stems afford extra shelter.

Squirrel Gliders are nocturnal, emerging from their nest shortly after dusk and not returning until later the same evening or in the early hours of the following morning. Depending on the food types they are seeking, animals emerging from their nest either move up into the canopy of trees, or glide down to smaller shrubs. Insects provide the bulk of diet throughout the year, which are gleaned either from leaves or other plant parts such as flowers, or from under bark. During key times of the year, such as winter, plant exudates such as sap, gum, honeydew and nectar, is a preferred food source.

In areas where the overstorey canopy is discontinuous, Squirrel Gliders may be forced to the ground in order to move from one patch of preferred habitat to another. This is particularly the case for offspring dispersing away from their maternal family group. In such circumstances, gliders may fall prey to introduced predators such as the Red Fox (Vulpes vulpes) and Feral Cat (Felis catus). Even if they avoid these predators, other perils may await. Barbed wire fences, in particular, are a hazardous boundary to movement, and in some landscapes gliders may perish after being caught and subsequently tangled on barbs.

A range of measures may help conserve the Squirrel Glider in woodland and riverine forest landscapes. First and foremost, protecting remaining large hollow-bearing trees, including dead ones, is vital to ensure den sites are available. In some areas where such trees are absent or few, establishing nest boxes may be a necessary alternative and may encourage gliders to move back into sites. To ensure a supply of den trees for the future, replanting schemes using local eucalypt species or allowing natural regeneration to occur may be critical. Enhancing the diversity of shrubs in the understorey may help provide alternative foraging substrates, particularly at sites where tree species diversity is low.

Species Profile: Squirrel Glider (Petaurus norfolcensis)

Photo: © P. Menkhorst, NSW NPWS

Status: In New South Wales the Squirrel Glider is listed as a Vulnerable species under the Threatened Species Conservation Act 1995. In addition, under the same legislation an Endangered Population of Squirrel Gliders is listed for the Wagga Wagga Local Government Area. The species has also declined in distribution in Victoria and is listed as Vulnerable under the Flora and Fauna Guarantee Act 1988.

Description: Squirrel Gliders are small arboreal (tree-dwelling) marsupials, characterised by blue-grey to brown grey fur above while the belly is a rich white or creamy white colour, There is a dark stripe between the eyes to the mid-back and the tail is soft and bushy. Squirrel Gliders are up to twice the size of their common relatives, Sugar Gliders, and their facial markings are typically more distinct.

Diet: Squirrel Gliders are primarily insectivorous but also cat seeds and plant exudates such as sap, gum, honeydew and nectar, as well as eucalypt pollen. The preference for inhabiting mixed-species eucalypt stands may be related to the more predictable availability of pollen and nectar at key times of the year (typically winter). In stands of simpler overstorey composition, such as River Red Gum forests, the absence of a reliable source of pollen and nectar may he compensated by the availability of gum from Acacia.

Reproduction: Breeding usually commences in late winter or early spring with young born between August and December. Average litter size is 13-2 young, depending on location.

Habitat: Across inland rural landscapes, Squirrel Gliders are mainly confined to dry sclerophyll woodlands and riverine forests, Eucalypt species known to provide suitable denning and foraging resources include Blakely's Red Gum, Grey Box, Red Ironbark, River Red Gum, White Box and Yellow Box. Shrub species in the genus Acacia also form key foraging habitat at certain times of the year.

Size: Adult Squirrel Gliders have a head and body length between 180-200 ram. Tail length varies from 220-300 min. Body weight ranges from 190-300 gms. Adult Squirrel Gliders have a head and body length between 180-200 mm. Tail length vanes from 220-300 mm. Body weight ranges from 190-300 gms.

Andrew is a Senior Threatened Species Office in the Southern Directorate of the NSW National Parks and Wildlife Service.

Contact Details: Email: andrew.clarige@npws.nsw.gov.au; Phone (02) 6298 9727