Thermal Drones Discover ‘Near-Mythical’ Tree Kangaroos

Researchers used thermal drones and unexpectedly discovered a rare species of tree kangaroo living in the wild in Australia.

In a recent study, a team of scientists revealed how they flew thermal drones — drones equipped with infrared cameras that detect heat signatures from the air — from a 154-foot crane in the Daintree Rainforest in Queensland, Australia.

Emmeline Norris, the lead author of the study, explains that the team originally set out to find spectacled flying foxes. However, the thermal drones quickly identified rare tree kangaroos by detecting their body heat in the rainforest canopy.

According to a report in Mongabay, the researchers spotted a species called the Bennett’s tree kangaroo, which is very rarely seen in the wild.

The Bennett’s tree kangaroo hasn’t been surveyed for many years and much is still unknown about these shy creatures including their population, life cycle, behavior, or even their diet.

Within just 20 minutes of the first thermal drone flight, the researchers spotted two Bennett’s tree kangaroos — one resting on top of the canopy and another below, feeding on vines. The following morning, the drones revealed four additional kangaroos.

In total, the thermal drones identified six Bennett’s tree kangaroos across 42 acres of forest, without seemingly disturbing or scaring the animals.

Using the thermal drone’s color zoom camera, Norris was even able to discover more about these tree kangaroos’ diet for the first time and identify the vines and leaves they were eating.

“It kind of blew my mind because I’d never seen them before in the wild,” Norris, a Ph.D. student at James Cook University in Queensland, Australia, tells Mongabay.

The use of thermal drones sheds light on this hidden species like never before. In the past, researchers surveyed tree kangaroos from the ground using methods like spotlighting, where a flashlight is aimed at the canopy to spot the animals’ red eye shine, or handheld thermal cameras.

However, Norris explains that spotlighting is only effective if the kangaroo is facing the light, and thermal cameras are limited to detecting kangaroos when they are low in the trees.

What are Bennett’s Tree Kangaroos?

Tree kangaroos are found only in the tropical rainforests of Australia and New Guinea. Unlike their ground-dwelling relatives, they live in the treetops, feeding on leaves and vines.

Bennett’s tree kangaroos reside in Australia’s most rugged and densely vegetated rainforests north of the Daintree River in Far North Queensland. They rarely come down from their vine-covered roosts, which can be as high as 130 feet.

Despite this, they are highly agile and can leap 30 feet down to another branch, and have been known to drop as far as 59 feet to the ground without injury. Their main predators are pythons and dingoes.

The full study has been published in Australian Mammalogy.

Image credits: All photos by Emmeline Norris, James Cook University.