UniSA spearheads first experiment using drones for wildlife health checks

Professor Javaan Chahl, DST Joint Chair at UniSA

A UniSA PhD student can now add ‘world first’ to her CV after collaborating with global cinematographer Douglas Thron to accurately measure heart and breathing rates of African wildlife filmed with a drone. Danyi Wang, working under the guidance of UniSA remote sensing engineer Professor Javaan Chahl, used sophisticated signal processing techniques to detect vital health signs of zebra, sable antelopes, waterbucks and giraffe from drone footage.

How vital has the technique been in saving wildlife?

It is believed to be the first time that this technique, pioneered by Prof Chahl and his team in 2019, has been used to extract heart and breathing rates of animals filmed from a drone at long distances. The collaboration with Thron, a high-profile drone pilot, came about after the cinematographer read about Professor Chahl’s remote sensing study with Adelaide Zoo.

Thron films using specialised drones with infrared cameras, zoom lenses and spotlights to rescue animals affected by natural disasters. He spent six months in Australia in 2020 after the World Wildlife Fund hired him to find vulnerable wildlife following the country’s bushfires.

That experience, and the world-first experiment in Malawi, features in a documentary series, named Doug to the Rescue, which airs in over 30 countries on the Curiosity Stream channel.

How effective was technique in collecting data?

In the Malawi edition, which premiered in mid-June, Wang and Prof Chahl are interviewed via Zoom, discussing the challenges they faced to pick up tiny movements from the animals’ chests filmed by Thron’s drone from ranges of over 50m. “We had to select the right sequences where it was stable enough to get heart rates, but we were able to do it,” he said.

According to Wang, the sable antelope’s heart rate was right in the middle of the normal range and its breathing rate was at the lower end, which indicated that it was very healthy and not stressed at all, even by the presence of the drone. Likewise, the vital signs captured from other animals such as giraffe, zebra and waterbuck were all in the expected range.

“It was exciting to work with a US-based documentary team on location in Malawi, via video conferencing from Adelaide, while Australia’s borders were closed. It just shows what is possible in a research context using modern technology, even in a pandemic,” Wang said.

How applicable is the technique in the conservation fight?

Prof Chahl says there is significant potential to use the same technology to monitor the health of wildlife globally, particularly endangered animals, and assist conservation efforts.

“We have demonstrated that a drone can be used to film wildlife at long distances without disturbing or stressing them, and then use AI techniques to successfully extract cardiopulmonary signals to remotely monitor for signs of poor health,” Prof Chahl said.

“This documentary was partly an experiment. Doug and his team wanted to verify that their work was not distressing the animals they try to help. Our results confirmed that.”

Wang was also part of the UniSA team who worked remotely with Canadian drone manufacturer Draganfly in 2020 to create COVID screening technology for humans.