Conservation status

Koala conservation is a complex issue. Populations are under severe pressure from habitat loss in many parts of Australia, yet in some areas the koala is common or even over populous.

Before 1900 koalas numbered in the millions, despite regularly suffering enormous losses to bushfires and disease epidemics. But in the first decades of the twentieth century extensive forest clearance and large scale hunting for the koala's warm, cheap, durable fur saw populations crash. The slaughter reached a peak in 1924, when over two million koala pelts were exported to Europe and America, and by the end of that year the species had been exterminated in South Australia and nearly wiped out in Victoria and New South Wales. A healthy population surviving in Queensland was next to suffer when in 1927 the state government bowed to commercial pressure and allowed an open season—600,000 more skins were exported.

Public outcry in Australia and abroad eventually resulted in legal protection, and since the 1920s intensive conservation measures, including captive breeding and translocation efforts, have allowed populations to partially recover. Today koalas are still under intense pressure in many parts of their range, but are not classified as threatened. The Australian government lists koalas as vulnerable, but has not put them on the country's endangered list. The World Conservation Union (IUCN) classifies koalas as Lower risk/Near Threatened, and lists habitat loss and degradation due to timber

A Queensland koala (Phascolarctos cinereus adustus) with young. (Photo by Kenneth W. Fink/Photo Researchers, Inc. Reproduced by permission.)
A koala grazes in a tree. (Photo by © Tom Brakefield/Corbis. Reproduced by permission.)

felling and urbanization, and human disturbance, particularly through fire, as the major threats.

Unfortunately, koalas inhabit precisely those eastern seaboard regions of Australia that are seeing most rapid urbanization and agricultural development. In the past 200 years an estimated one-third of Australia's eucalyptus forest has disappeared, and in semi-arid parts of Queensland, thousands of acres of woodland are still being cleared for agricultural use every year. Urbanization and tourist development along the coastal strip is further fragmenting eucalyptus woodlands. Bush fires caused by negligence or arson account for thousands of deaths each year, while an estimated 10,000 koalas are killed in road accidents. Koalas put up no resistance to attacks from domestic dogs, and do not cope well with stress, having abnormally small adrenal glands. There is also evidence that inbreeding in isolated, fragmentary populations is leading to physical abnormalities.

Despite all these pressures, there are actually locations where koala populations have thrived to such an extent that they are causing environmental damage. Koalas were translocated to a number of islands where they were not found naturally as long ago as the 1870s. Populations on Phillip and French Islands in Victoria, and Kangaroo Island in South Australia have grown so large that the unpalatable prospect of culling has been proposed. Thousands of animals have been relocated back to the mainland, causing similar overcrowding problems in some locations, and contraception is being investigated as a more publicly acceptable alternative to culling.

One possible explanation for these overpopulation problems is that the island populations are free of chlamydia, a disease that is now thought to have been endemic in koalas for many years, and may have acted as a natural population control, remaining benign when conditions were good, but killing off weaker animals during stressful times such as when habitat is reduced.

Some koala conservation work, including purchase of land for protected reserves, is being carried out by state authorities, but much koala conservation and research is in the hands of charities and privately-run welfare organizations. The koala's cute and cuddly appeal helps raise funding for such non-government organizations.

One problem in planning conservation management is the difficulty in obtaining accurate population figures. The Australian Koala Foundation suggests numbers have dropped from 400,000 in the mid-1980s to between 40,000 and 80,000 today, but this estimate can only be an educated guess. The Foundation is compiling a national atlas of surviving koala habitats, which will provide a tool to lobby for habitat conservation.

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