Thursday, June 23, 2011

Are Australia's Koalas, Battling Climate Change and Chlamydia, On the Path to Extinction?

Although they appear in just about every Australian postcard, koala bears are actually quite hard to spot in the wild, where their numbers are gradually declining. Scientists are now sounding the alarm — and urging Australia's senate to declare the iconic, sleepy-eyed marsupials an endangered species.

Scientists estimate Australia's koala bear population at somewhere between 50,000 and 100,000. "We cannot be totally sure because we don't receive enough public subsidies to thoroughly study the subject. But it is clear that the number is dropping," says Alistair Melzer, a senior researcher at Queensland University. In the Gold Coast region, the number of koala bears seems to have decreased by as much as 80% since the 1990s. (See photos of koalas in Australia.)

There are several factors that might be pushing koala bears close to extinction. Topping the list is urbanization and farming, which have destroyed the cuddly creature's natural habitats. For both food and shelter, koalas rely on large eucalyptus trees that grow in only specific places.

"Unfortunately, the places where koala bears thrive are also the best spots for human beings, namely places with fertile soil," says Melzer. Koala bears are in real trouble when their habitats shrink and they have no other choice but to live near cities. Proximity to humans can mean attacks by domestic dogs, or fatal run-ins with automobiles.

Moreover, the tree-dwelling animals suffer from heat waves and drought, which are likely to be more frequent because of climate change. Koala bears cannot cope with high temperatures, and they need to get moisture from eucalyptus leaves. "If climate change predictions play out, koala bears won't migrate to the South, where temperatures are lower. As a result, they will just die," says Melzer. (read more)