How much can a koala bear?

A changing climate means that by 2070 koalas may no longer call large parts of inland Australia home, a University study has shown.

Using a detailed ecological model, researchers found hotter temperatures and altered rainfall patterns will make it more difficult for koalas to get the water they need – making inland populations vulnerable to heat-stress.

The researchers mapped potential koala habitats in 2070 by using information about koala behaviour, physiology, body size and fur to predict how much energy and water the marsupials need to survive under the climate at a particular location.

They found that the climatically suitable area will be dramatically reduced by 2070, particularly in Queensland.

The koala’s range across Australia was limited by water requirements for keeping cool, with the timing of rainfall and heat waves being crucial in limiting the area in which koalas live.

Lead author of the study Dr Natalie Briscoe (BA 2006, BSc(Hons) 2007, GCALL 2012, PhD 2014), from the School of BioSciences, says the findings could help in forecasting future impacts of climate change on biodiversity.

“Studies of climate change impacts on wildlife have often focused on how changes in average temperature or rainfall will affect species, but our research highlights the importance of thinking about the extreme conditions that will be most stressful for the animals – such as hot, dry periods – and how these may change in the future.”