More than one billion animals are thought to have been killed in bushfires across Australia but experts warn the environmental devastation could span decades.
Australian mammal expert Professor Chris Dickman first estimated that half a billion animals had been killed in the bushfires this season, but now believes more than double that figure have perished.
"One billion sounds like a very big number but it's almost certainly an underestimate because of the groups I don't include," the University of Sydney academic told AAP on Thursday.
Bats, frogs and invertebrates haven't been included in the estimate.
Professor Dickman said the bushfires this season have been different because they've come after a long drought.
"They've burnt very quickly allowing less chance for animals to get away, they're burning very intensely and they've covered a much huger area," he said.
The worst-affected animals would be the "large and slow-moving ones" such as koalas but species with small populations are at risk of imminent extinction, he added.
"We're clearly at risk of losing a significant proportion of biodiversity and because much of Australian biodiversity occurs only here, it's a global loss," he said.
Dr Christine Hosking from the University of Queensland's Global Change Institute said one billion dead animals is a "very reasonable" estimate.
While many animals would have perished in the blazes, many more will die because of a lack of food and the charred, barren landscapes which leave small mammals vulnerable to predators, she said.
"The whole food chain is affected," Dr Hosking told AAP on Thursday.
"These forests will remain empty for quite a long time."
The koala expert believes it could take up to 100 or even 200 years for some forests to completely recover and the ecology will not only be degraded, but changed completely.
"We've got threatened species that may go extinct after this as well," she said.
Dr Hosking called for a national workforce dedicated to protecting the environment during and after disasters such as bushfires.
She said the workforce needs to be separate from those which protect human life and property, instead focused on rehabilitating the nation's biodiversity.
"It's time the environment is put first," she said.
Australian Associated Press