No, koalas are not 'functionally extinct', but they are in trouble

Who has said koalas are “functionally extinct”?
The Australian Koala Foundation, which lobbies for the animals’ protection, has put out a press release stating that it “believes koalas may be functionally extinct in the entire landscape of Australia”. The release triggered a flurry of worried headlines.

So are they?
No, although many populations of koalas are falling sharply due to habitat loss and global warming.

Could they go extinct?
There is no danger of koalas going extinct in Australia overall, says biologist Christine Adams-Hosking of the University of Queensland, who has studied the marsupials’ plight. “But at the rate of habitat clearing that is going on, we are going to see increased local population extinctions,” she says.

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What about climate change?
It is already having a big impact, says Adams-Hosking, causing some populations to decline 80 per cent. Koalas can’t cope with day after day of temperatures above 36°C, as has been happening in the west of the country during the many recent heatwaves. Extreme droughts are also harming the eucalyptus trees they feed on.