Attacks on humans by carnivorous animals have increased steadily since 1950, as growing human populations in new areas make such incidents more common, according to a study published last week. According to other experts, climate change may also be contributing to increased human-wildlife conflict.
The report, which includes 33 contributors, was published in the peer-reviewed journalPLOS Biology. Spanning 70 years, the collected attack incidents were compiled from personal datasets, published literature and news reports.
A contributor to the report, Vincenzo Penteriani, an ecologist at the Spanish National Research Council, said rising population has led to increased human encroachment on natural habitats — a probable cause for the purported uptick in attacks by wolves, bears and big cats all over the world.
Penteriani said that while the overall number of carnivore attacks has increased, such incidents are still relatively rare. The report found that Asia and Africa have had the sharpest increases.
“If you combine the reduction of natural habitat with the expansion and spreading of human settlements, it’s almost normal that the encounters between large carnivores and humans become more frequent,” Penteriani said. “It’s just a question of probability.”
Climate change that brings wildlife closer to humans may be another aggravating factor in human-wildlife conflicts, said Briana Abrahms, an assistant professor and wildlife ecologist at the University of Washington who did not work on the study.
Most carnivore attacks in high-income countries occurred during recreational activities such as hiking or camping. In low-income countries, carnivore attacks occurred more commonly among people engaging in livelihood activities such as hunting or farming. Globally, 32% of all attacks were fatal, according to the study.
Abrahms said that it is important to recognize all variables that affect human-wildlife interactions and that climate change is often missing from the discourse.
“We’re seeing the long-term impacts, such as the decline in sea ice in the Arctic, leading to increased encounters between polar bears and people,” Abrahms said. “But also, we’re seeing the more immediate impact of extreme climate events. The increasing frequency and severity of these events can drive conflict — for example, in sub-Saharan Africa, extreme drought frequency has been associated with increased carnivore attacks on livestock.”
Last month, a polar bear killed a 24-year-old woman and her 1-year-old child in the small village of Wales, Alaska. It was the first fatal polar bear attack in Alaska in over 30 years. Polar bears are spending more and more time on land, Abrahms said, as their hunting grounds on the ice shrink.
Penteriani said: “It’s difficult to predict the full impact of climate change on carnivores. But if at the end of the summer polar bears are unable to return to their habitat because of the lack of ice, they will have to remain closer to humans for longer periods. This automatically increases the possibility of more attacks.”
Wildlife behavior may be more closely tied to human activity than previously acknowledged. A recent study found significant differences in land use and behavior among several species in Glacier National Park in Montana during and after Covid closures.
Researchers found that hikers created a “landscape of fear” for cougars, wolves, black bears, grizzly bears and smaller mammals. When the parks were empty, the animals roamed freely. When hikers returned, several species used hiking trails less or disappeared entirely.
Generally, wild animals try to avoid contact with humans, said a co-author of the study, Daniel Thornton, an assistant professor at Washington State University studying carnivore ecology and conservation.
“When animals are forced into close quarters, when there’s not enough habitat or you have these climate-driven changes that are pushing animals and people together, that’s when conflict is more likely,” Thornton said.
Urban ecologist Christopher Schell studies how animals and humans are adapting to increased proximity in urban settings. His laboratory at the University of California, Berkeley, where he is an assistant professor, is home to research about urban human-coyote interactions.
With increasing global urbanization and human encroachment, it is inevitable that human-wildlife interactions will increase, Schell said. But those interactions do not need to be negative, he added.
“Something to consider are the relationships that already exist between people and the species in question,” he said.
Schell considers the urban tale of Carl the coyote a perfect representation of humans’ changing relationship with carnivores in cities. Carl was the beloved mascot of the San Francisco Bay area, Schell said. He was fed and doted on by the local unhoused population but eventually grew too accustomed to humans — after authorities deemed Carl was a threat, particularly to local children, he was shot in 2021, inspiring a citywide vigil.
“There are many species that are going to be urbanized, that are urbanized right now,” Schell said. “We know that wildlife is most likely going to be interacting with people more frequently, and we need to be prepared for it. How do we create spaces that allow for both wildlife and humans to coexist?”