The Kangaroo Island Koala, and its history on the Island
Koalas were not on Kangaroo Island at the time of European settlement, and in the 1920s 18 koalas were released in Flinders Chase National Park to save their declining mainland population from the ravages of the fur trade and land clearance. Over time the population became established, with increasing numbers and distribution as the disease-free population expanded.
Only about 1% of Kangaroo Island is a highly preferred Koala habitat and in time their over browsing has damaged some species of eucalypt trees, across large areas of habitat. To counteract this the Koala Management Program began on Kangaroo Island in 1997 and the population is carefully managed. In the summer of 2019-2020 bushfires had an impact on Koalas and their habitat across western Kangaroo Island and the population continues to be closely monitored.
Koalas, one of Australia’s iconic pouched marsupials, have thick grey-brown fur with white-tipped fluffy ears, with body proportions similar to that of an infant human. The Kangaroo Island Koala differs to their Queensland and News South Wales counterparts slightly in appearance with larger body weights, longer fur and fluffier ears. Fully grown male Koalas can weigh up to 15 kilograms, and females up to 11. Koalas breed from October to May, with young seen regularly on the back of their mothers throughout spring and summer. Koalas can give birth to twins, although this is rare.
Koalas eat leaves from a few eucalypt species, which generally grow along the river systems on Kangaroo Island. They can eat up to 1 kilogram of leaves a day, have extremely sharp claws and a very powerful upper body allowing them to be world-class tree climbers.
Where to find them
The Koala spends much of the day resting in the treetops, often nestled into the fork of a tree seemingly fast asleep. When feeding you will spy them high up in the canopy and sometimes out near the branch ends reaching for tender leaves. Tending to move around at dusk and the early evening to feed, keep an eye out for their ball-shape high in the canopy, resting in a fork, or moving between branches. Koalas occur in riverine habitats right across Kangaroo Island, except for the Dudley Peninsula. Particularly favouring eucalypt habitats including manna gum, blue gum, stringy bark, or river red gum, however, they have been known to rest in other tree species also. Great opportunities for viewing are the scenic walking trail along Cygnet River at Duck Lagoon, accessed via Kookaburra Road, Kangaroo Island Wildlife Park or the Hanson Bay Wildlife Sanctuary. Koalas are often an opportunistic sighting when out enjoying a walk in the eucalypt habitats across the Island.
How to watch them
Koalas spend between 18–20 hours of each day resting or sleeping, 1–3 hours feeding and the remaining time moving, grooming, or socialising. Vocalising Koalas aren’t generally the norm, but when they do make a noise, it can be quite unexpected and surprising. Male Koalas produce a deep bellowing and snorting type noise, most often heard during the breeding season. All Koalas can make sounds, females, and juveniles generally only call out in a high-pitched squeak or squeal when they feel threatened or agitated. Koalas tend to be observed as very quiet and nonchalant, usually seemingly unperturbed by what is going on about them. Watch them quietly from a distance to ensure they get the rest they need.
Did you know?
The ability to survive on a diet of eucalypt species alone is only shared with very few Australian animal species, including the Greater Glider. Relatively low in essential nutrients, eucalypt leaves also contain nutrients that are toxic to most animals and contain compounds that impede digestion. The Koala must therefore use precious energy and protein to detoxify these compounds and remove them from their bodies, one of the reasons Koalas are so careful at conserving energy.