Graphic reality of koala bush fire deaths on Kangaroo Island

Animals killed in the fires on Kangaroo Island. Photo / HSI

WARNING: Distressing images

As firefighters anxiously watch the fires still burning on South Australia's Kangaroo Island, animal rescuers are moving in to survey the damage.

Aussie animal rescuers have been working on the island for weeks now but pictures taken by Humane Society International has shed a heartbreaking light on the fate so many koalas and kangaroos suffered.

"These are some of the toughest scenes I've ever witnessed: The bodies of charred animals as far as the eye can see," HSI's senior disaster response specialist Kelly Donithan said in a video.

A dead joey on Kangaroo Island. Photo / HSI

"We've seen kangaroos with devastating burn injuries and dehydrated koalas gasping for water. We found one kangaroo so burned her feet and tail were nothing but exposed bones.

"Amidst all this death, every time we find an animal alive it feels like a miracle."

It's estimated up to 25,000 koalas – half the population – were killed in the Kangaroo Island bushfires.

More than 8000 are believed to have died in northern NSW.

Flare-ups across the Kangaroo Island bushfire are expected to continue for up to two weeks, as fire crews battle to bring it fully under control. The blaze has already burnt through 210,000 hectares inside a 588km perimeter, destroying 65 homes and hundreds more buildings.

Animals could not escape the flames on Kangaroo Island. Photo / HSI

Animals killed in the fires on Kangaroo Island. Photo / HSI

A lone koala on Kangaroo Island. Photo/ HSI

The Country Fire Service says it is still burning in various spots along the 120km eastern flank.

Almost 400 firefighters are still deployed on the island with 83 fire trucks supported by 130 farm fire units.

Australian Defence Force Chief of Joint Operations Lieutenant General Greg Bilton said there was a significant number of livestock and wildlife burials underway, and that authorities were working quickly to reduce hygiene risks.

At least 400,000 litres of drinking water is being provided for KI residents for human consumption and stock consumption.