Unmanned aerial vehicles (UAVs), commonly called drones are taking over the skies. Just a few years ago, there were only a few thousand remotely controlled flying drones across the entire globe, mainly owned by the military. Today, there are literally millions of drones dotting the skies, and there will be tens of millions of UAVs buzzing around, including many with commercial applications, by 2020.
Drones today serve a number of purposes, ranging from recreation to research to delivery, but they can be bothersome and even dangerous if they come too close to people, animals or important infrastructure. Related to this, drones are increasingly being used around wildlife of all sorts, and a new study from the University of Minnesota highlights how exposure to drones has a negative effect on the health if black bears.
The study was published this week in the academic journal Current Biology, and offers strong evidence that black bears are physiologically stressed by the presence of UAVs, even if it can’t be immediately observed in their behaviors.
Using drones in the wild to observe nature
Somewhat ironically, it turns out one of the biggest research-related uses of UAVs is scientists, conservationists and ecotourists trying to get up close and personal with nature. Drones have been used used to ward off poachers in Africa and elsewhere, for cave and mountain exploration, and collect to data on the migratory patterns of humpback whales and the behaviors of other animals. Both professional and amateur drone users regularly take videos and photographs of wildlife in their natural habitats.
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.
Carefully observing animals’ reactions to the presence of drones is very important for figuring out how much stress the drones are creating for the local animals, according to the University of Minnesota wildlife biologists. Study lead author Mark Ditmer, a postdoctoral researcher in the University of Minnesota’s Department of Fisheries, Wildlife and Conservation Biology, commented in an interview with the media that he hopes the publicity surrounding this study will lead to further research on the subject.
Methodology for the study of the impact of drones on bears
Ditmer and the other researchers studied four bears in northwestern Minnesota (two mothers with cubs, one hibernating female, and one young male). They equipped the nears with GPS collars and “biologger” devices to collect heart rate data. Carrying out the study involved flying a drone over each bear from one to nine times while observing movement patterns and heart rates of the animals.
The data showed that all of the bears’ heart rates increased when the drones flew overhead, which would clearly suggest they were stressed by the flying machines. However, even though the bears’ hearts were racing, the bears typically froze in place rather than try run away from the drones.
Future research on the impact of drones on wildlife
The goal of future research would be to see if repeated drone use is likely to be harmful to bears and other animals. Ditmer noted, for example, it’s even possible the bears could become used to drones over time and eventually be less stressed. Research could also investigate if different heights, speeds or even sound frequencies are more or less likely to lead to stress on animals.
Ditmer emphasized, however, that this study is not meant to lobby against the use of drones, which are clearly valuable in conservation and research applications. “We’re just highlighting a potential issue that needs to come into closer consideration when we decide where and where to use them,” he explains.