The Feathertail Glider (Acrobates pygmaeus) is the world's smallest gliding mammal, and one of only two representativies of the family Acrobatidae. (The other is the slightly larger Feathertail Possum of New Guinea.)
It is a rarely seen but probably quite common inhabitant of tall forests and woodlands from Cape York to near Adelaide. Because of its size and nocturnal habits it is difficult to study, but it appears to prefer undisturbed areas with high plant diversity and reasonable rainfall.
Although only the size of a very small mouse (65 to 80 mm long and 10 to 14 grams), the Feathertail Glider can leap and glide long distances from tree to tree, up to 25 metres. Like other gliding mammals, it has a skin membrane between the fore and hind legs; thicker than that of the other marsupials like the Sugar Glider, but smaller in proportion, extending only between the elbows and knees.
The most obvious feature of the Feathertail Glider, however, is the tail that gives it its name: it is about the same length as the combined head/body, quite thin, moderately prehensile, and almost hairless except for the two very obvious rows of long, stiff hairs on either side. The tail, when held straight, looks rather like a double-sided comb. It is used to grip twigs and small branches, and to control gliding flight: steering and then braking.
The coat is a uniform mid-grey, with dark patches around the eyes and often a white patch behind the ears. The underside is lighter; the ears are moderately large and rounded.
Feathertail Gliders live in large social groups (around 10 or 20 individuals), and feed at all levels of the forest, from on the ground to high in the canopy. The diet includes nectar, pollen and insects; Banksia and Xanthorrhoea flowers seem to be particularly attractive.
Captive studies indicate that breeding will not take place below a certain minimum group size (about 7 individuals). In the wild, Feathertail Gliders breed all year round in the north, and at any time except winter in the southern states, often having two litters a year.
Females give birth to 2 to 4 young, which then spend 65 days in the pouch, and are weaned after 100 days. Mortality of pouch young is low, but independant individuals are vulnerable to a number of predators, including cats and foxes, larger marsupial carnivores, owls, Ghost Bats, and goannas.