Ecologists say more than half a billion creatures have been killed by bushfire pushing rare species to extinction as feral cats move in to pick off the starving survivors.

Kangaroo Island, South Australia, last week had a rare population of tiny marsupials called dunnarts.

Ecologist Pat Hodgens had set up cameras to capture the insect-eating mouse-like creatures.

Pat Hodgens holds up the burnt remains of two cameras set up to capture the rare Kangaroo Island dunnart on Thursday (left). Ecologists are concerned it may now face extinction. Pictured right: Pat Hodgens with a dusky hopping mouse native to arid lands

The Kangaroo Island dunnart is a marsupial found only on Kangaroo Island in South Australia. Its future looks grim after fires ripped through conservation areas earlier this week destroying fences, cameras and habitat

Two fires burnt through the site earlier this week, melting cameras and fences set up to record and protect the rare creatures, and incinerating their habitat.

On Friday the island was again torched along its south coast, destroying three other wildlife sites that protect dunnarts and the endangered southern brown bandicoot.

On Saturday the island was again on high alert again as news broke that two people were killed in the fire that has burnt up to 100,000 hectares since it began in December.

It is not known how many Kangaroo Island dunnarts survived.

Australian National University professor Sarah Legge said the future for the Kangaroo Island dunnart did not look good.

An urgent cull of feral cats and foxes has been called for as they are attracted to burnt areas where they hunt native survivors easily after the protective bush cover has been burnt away

Ecologists fear the bushfires may cause several species to become extinct.

Professor Legge said many dozens of threatened species had been hit hard by the fires and that some species had seen their entire range of distribution burnt out.

Sydney University Ecology Professor Chris Dickman said 480 million animals had been killed in New South Wales alone including mammals, birds and reptiles.

That number does not include insects, bats or frogs that are essential to the health of an ecosystem.

'The true loss of animal life is likely to be much higher than 480 million,' he said on Friday.

Kangaroo Island Land for Wildlife shared this photo of a burnt survey fence line and wildlife camera on Thursday. The island was torched again on Friday by bushfire

'Many of the affected animals are likely to have been killed directly by the fires, with others succumbing later due to the depletion of food and shelter resources and predation from introduced feral cats and red foxes.'

Professor Dickman said Australia is the only great landmass to contain three major groups of mammals: marsupials which have pouches, egg-laying monotremes and placental mammals.

The continent contains 244 species of wildlife found nowhere else.

'Some 34 species and subspecies of native mammals have become extinct in Australia over the last 200 years, the highest rate of loss for any region in the world,' he said in a statement on Friday.

Ecologists fear the catastrophic fires have pushed back conservation efforts by decades and some species may become extinct as a result.

Australian National University Ecology Professor David Lindenmayer said the half a billion animals directly killed by fire was just the beginning.

'The big issue is that after the fire a lot of animals have lost their habitats and have nowhere to feed or shelter,' he said.

Professor Lindenmayer told Daily Mail Australia that feral predators like cats and foxes would go to the burnt areas to hunt the surviving native wildlife.

Tracy Dodd, a volunteer with the Wildlife Information, Rescue and Education Services, holds a kangaroo with its feet bandaged after it was burned in the wildfires

A badly-burned possum carrying a baby in its pouch is treated at a wildlife centre in New South Wales. Ecologists fear native survivors will now become easy prey for feral cats and foxes

'They're attracted to burnt areas as they can forage and find food easily since the vegetation cover has been removed,' he said.

Professor Lindenmayer said it was important for management agencies to start controlling feral animal populations straight away to protect the remaining animals so they may survive.

Since the start of bushfire season, roughly 5.8 million hectares of land has been burnt so far by intense fires feeding on eucalyptus fuel dried by years of drought and whipped up by strong winds in extreme summer temperatures.

That is more than the devastating Canberra bushfires of 2003 where almost 4 million hectares of bushland was burnt across five states.