During Australia’s summer months, over a fifth of the nation’s forests were destroyed by aggressive bushfires, killing over a billion animals. An area particularly devastated was Kangaroo Island, just off the coast of Adelaide in southern Australia. Here, satellite data showed that nearly 50 percent of the island had been burnt as of early February – the largest amount in the island’s recorded history.
Residents suffered huge losses, whilst precious habitat and wildlife perished. Indeed, the widespread destruction of timber plantations by the fires, claimed the lives of up to 45,000 Koalas – 90 percent of the island’s total population.
Some of the survivors have been rescued and nursed back to health in wildlife sanctuaries, but scientists are still working to identify where the remaining wild populations still live. But all methods for koala spotting are fraught with challenges, whether it's just looking through heavy bushland, or using dogs to sniff out the marsupial.
“We never have perfect knowledge, so we never know exactly how many koalas were there when we do a count,” Evangeline Corcoran, a PhD student at Queensland University of Technology (QUT), said in a statement.
To help improve their estimations, and reduce their margin of error, Corcoran and her colleagues, Professor Grant Hamilton and Dr Simon Denman, have devised a novel koala finding method, using drones, infrared imaging and AI, published in Ecology and Evolution.
Drones equipped with infrared imaging cameras scan the landscape in a “lawnmower” pattern picking up the body heat of animals. This data is then fed through an algorithm designed to identify the heat signatures of koalas specifically. Quicker, cheaper, and less invasive than traditional techniques, previous tests of the system have shown it to be more reliable as well.
“On average, an expert koala spotter is going to get about 70 percent of koalas in a particular area,” Hamilton said in a previous statement. “We, on average, get around 86 percent. That’s a substantial increase in accuracy that we need to help protect threatened species.”
As Australia plunges through winter, the heat of koalas will better stand out against its surroundings, providing the perfect opportunity to gather information on the whereabouts of Kangaroo Island’s remaining koala population.
“In this way, we are deriving a count figure that accounts for more factors such as temperature, which is an important consideration because our thermal cameras give a more accurate estimate when it’s colder, and the density of the forest canopy,” Corcoran said.
On the topic of koalas, have you ever wondered what they sound like? If you're thinking a cute squeaking sound then you’re in for a shock…