New and expanding mining leases across central Queensland's Bowen Basin could make it even harder for koalas to survive, environmentalists have warned.
A study from Central Queensland University has found 42,000 hectares classified as potentially suitable koala habitat would be under threat from 12 proposed mining developments in the region.
The total area is more than 17,000 times the size of the Gabba.
Michael Hewson, a senior lecturer in geography at the university, said koala habitat in the Bowen Basin had declined by more than 40 per cent from colonisation to 2020.
"In the last 40 years, potential koala habitat has declined by 12 per cent," he told AAP.
The study, which was commissioned by Lock the Gate Alliance and Environmental Advocacy Central Queensland, used government data and satellite mapping to determine how the mining leases would overlap with potential koala habitat.
Environmental Advocacy Central QLD director Coral Rowston said federal environment minister Tanya Plibersek must take action to protect central Queensland's koalas.
"If Minister Plibersek approves these new coal projects, thousands of hectares of habitat will be cleared and the extraction and use of the coal mined will fuel climate change, making it even harder for koalas to survive," she said.
"Central Queensland’s koala population would face a very perilous future under the business as usual approach of rubber stamping the majority of Bowen Basin coal mines."
Lock the Gate Alliance national coordinator Ellen Roberts said it was ironic the government was putting forward a koala as the mascot for Brisbane's 2032 Olympics, while approving developments that impact their habitat.
"Australia will be an international embarrassment if it continues to allow the wide scale destruction of koala habitat even while trying to promote the animal to the world," she said.
Dr Hewson said central Queensland is home to about a fifth of the state's koala population, and it's important to understand the cumulative impact their habitat is facing before approving new developments.
"The impacts of one extractive industry entity on the environment is a certain size, but by the time you have 83 such entities then the cumulative impacts on the environment are something completely different," he said.