KOALAS are under threat from rising levels of carbon that poison their only food source, eucalyptus leaves.
A scientist has warned that climate change — specifically rising levels of greenhouse gases — is pushing up toxins and lowering nutrients in eucalyptus leaves. Dr Dan Lunney, of the NSW Department of Environment and Climate Change, said the trend would force koalas on to the ground to search for food, putting them in danger.
"What currently may be good koala habitats will become very marginal habitats," he said. "This means koalas have to change trees more often to get to the leaves they need … If they walk across the ground, they are vulnerable to dogs, and if there are roads in the middle they are vulnerable to cars as well."
Koalas are listed as a vulnerable species. Among the biggest threats to their survival are land clearing, bushfires and drought. They are also notoriously fussy eaters. Of 700 types of gum tree, they will eat the leaves of only 25.