The Koala Fact Sheet

makes up plant cell walls. To obtain enough food, an adult koala must eat more than half a kilogram of leaves every day. The cheek pouches store extra food until it can be chewed. Eucalypt leaves, which form the bulk of a koala’s diet, contain strong-smelling oils and phenols poisonous to most mammals. Koalas are able to detoxify these substances in their livers. Eucalypt leaves may also contain cyanide- type compounds, but these leaves are probably selectively avoided. Some of the preferred eucalypts may be toxic at certain periods of growth and it is therefore important for koalas to have more than one species to feed upon. Eucalypts favoured for food around Brisbane include the Forest Red Gum (Eucalyptus tereticornis), Grey Gum (E. propinqua) and Tallow-wood (E. microrys). In other parts of Queensland the Poplar Box (E. populnea), Bowen Ironbark (E. drepanophylla) and River Red Gum (E. camaldulensis) are favoured. Breeding Koalas are summer breeders and usually produce a single offspring once a year, although twins are relatively common. The young are born after 35 days gestation and spend 6 months in the pouch after birth, followed by another few months living on the mother’s back. Koala, Phascolarctos cinereus. Image: QM, Gary Cranitch. Adult koalas (4 years or older) are usually solitary, although the males may form harems during the mating season. Introduction Conservation The koala (Phascolarctos cinereus) is one of the most Millions of koalas were slaughtered in the 1920s for their familiar native Australian mammals. It is easily recognised thick, soft fur and in 1924 two million koala pelts were by its soft grey and white fur, large hairy ears and black exported from Australia.w bulbous nose. Although often called a ‘koala bear’ or Concern about the possible extinction of the koala led to ‘teddy bear’, it is a marsupial and is not related to the true itsw total protection in the late 1920s. It is now widespread placental bears. The name ‘koala’ is an Aboriginal word and reasonably common in open forests and woodlands meaning ‘no drink’, a broadly appropriate description in south-eastern Queensland, eastern New South Wales, considering koalas usually obtain sufficient moisture from Victoria and eastern South Australia. In Queensland, their diet of leaves, but the same is also true of most of the isolated populations also occur in the central eastern and possums. north-eastern parts of the state. The koala is the only living representative of the family Recently, there has been considerable concern that many Phascolarctidae. Its closest relatives are the wombats. female koalas may be sterile due to infection with the Fossil remains of koala-like creatures that are about 15 bacteria Chlamydia psittaci. Isolated populations also million years old are known and it a likely that koalas and remain highly vulnerable to habitat disturbance, especially wombats shared a common ancestor about 25 million years from land clearing and fire, leaving the long-term future of ago. Certainly, they share many similar characteristics: the koala uncertain in many areas. both have vestigial tails; cheek pouches; backward-opening Further Information pouches for carrying their young; few premolar teeth; and Bergin, T.J. (Ed.), 1978. The Koala, Proceedings of the Taronga unique blood proteins. Symposium. Zoological Parks Board of NSW, Sydney. Koalas are mostly nocturnal (active at night) and arboreal Lee, A. & Martin, R., 1988. The Koala - a Natural History. (tree dwelling).They rarely descend to the ground, and University of New South Wales Press, Sydney. when they do it is usually only to move from one tree to Martin, R., 1992. Of Koalas, Tree Kangaroos and Men, another. They are well adapted for climbing and possess Australian Natural History, 24(3): pp.22-31. very long arms and powerful claws. The first and second fingers are opposable to the other three, allowing a strong Ryan, M. (Ed.), 2007. Wildlife of Greater Brisbane. Queensland grip while climbing. Wild koalas are usually inoffensive, but Museum, Brisbane. if handled they may scratch and bite. Van Dyck, S. & Strahan, R., (Eds.), 2008. The Mammals of Australia, 3rd edition. Reed New Holland, Sydney. Diet Author: Steve Van Dyck Koalas are highly specialised herbivores and possess Queensland Museum an enormous caecum (appendix) up to 2.5 m long. The PO Box 3300, SOUTH BRISBANE QLD 4101 caecum is necessary for the digestion of large amounts Phone: (07) 3840 7555 of eucalypt leaves that are high in fibre and very low in http://www.qm.qld.gov.au/ protein content. Within the caecum, a fermentation process involving millions of bacteria decompose the cellulose that