The heatwave is taking its toll on a colony of flying foxes with about 90 found dead on the ground in Adelaide's Botanic Park.
Many of the creatures, which have travelled from the eastern states, have dropped from the trees either dead or dehydrated.
Trained and vaccinated volunteers are collecting the carcasses, which are mostly juveniles, and are caring for ones that are badly heat stressed.
Environment Department ecologist Jason van Weenen says about a tenth of the colony has died in the current heatwave.
He says the creatures cluster together during times of heat stress and suffocate each other.
"The clustering is quite a concern. They're really getting exhausted and starting to pile up on top of each other and then it makes it even more difficult for them to manage their temperature," he said.
"A total of 90 bats have died so far in this heatwave, but it's anticipated that as we are getting even hotter temperatures today, more will perish.
"The colony is exhibiting some really classic signs of heat stress. They're clumping, they're doing lots of fanning behaviour.
"They're trying to get down, get lower in the canopy trying to cool down."
People have been advised not to touch the bats if they find them on the ground.
"Sick and injured bats can still struggle and scratch and that way they can transmit diseases," he said.
"If they come across a dead animal, contact Fauna Rescue."
About 100,000 bats died in a heatwave last week in Queensland, where the bat population is much bigger.
In Adelaide's parklands last summer about 100 died from heat stress and a sample taken from one later tested positive to Hendra virus.