Drones Used for Wildlife Observation Cause Bears’ Hearts to Beat Significantly

Bears may be more bothered by drones than their outward behavior suggests.

Drones are increasingly common in U.S. skies.

He found that all four bears were put under heavy psychological stress beneath the buzzing of UAVs. In addition to being a valuable research tool, the UAV has been used to discourage poaching and to locate animals for ecotourism.

Drones today serve a number of purposes, ranging from recreation to research to delivery, but they can be bothersome and even unsafe if they come too close to people, animals or important infrastructure. So Mark Ditmer of the University of Minnesota, St. Paul, and colleagues tested the reactions of four black bears in northwestern Minnesota – two moms with cubs, a 1-year-old male and an adult female who had just entered her hibernation den, each of which had been outfitted with a Global Positioning System collar and heart monitor.

A study published Thursday in the journal Current Biology found that bears are unsettled by the presence of unmanned aerial vehicles (UAVs). When they flew 18 UAVs over the bears, with each bear facing a different number of flights, all of them showed a spike in their heart rates, rising as much as 123 beats per minute when compared to pre-flight baselines.

Now, another group of researchers finds that despite the calm demeanor bears may display in the presence of airborne robots, drones make bear heart rates soar, a major sign of stress.

Next, they programmed a UAV to fly to the bear’s most recent location, and monitored the data to see how the bears reacted to the five minute long drone flights.

The cardiac monitors were developed for humans, but they’re in the bears as part of an effort to understand how bears manage to hibernate through the winter – and then resume their normal activity with no problems.

“We felt that the size of the stress response warranted us to write this paper as a cautionary tale”, he said. Also, because of drones, the animals may expose themselves to risky situations, and could become more “vulnerable to sources of mortality”, Ditmer explained.

That said, despite the fact that drone use is becoming commonplace among wildlife researchers and enthusiasts, practically no research on how animals actually react to UAVs has been undertaken. This effect could be more pronounced in animals unfamiliar with the hustle and bustle of human existence.

The end goal would be to figure out whether repeated drone use is likely to be harmful to animals.

Perhaps the bears will get used to the drones – the researchers are now exploring that possibility in studies with captive bears. Other types of wildlife would respond differently to the unfamiliar sound of a drone, said Ditmer.

To be clear, Ditmer says, his team’s study is not meant to advocate against the use of UAVs, which have high potential for both conservation and research applications.

“Just because we’re not noticing an animal changing behaviour, that doesn’t mean there’s not some sort of negative response happening”.