What happened to wild animals during the pandemic?

To date many people have entered into a simplistic understanding of what happened in the wild during the pandemic. But according to new research, things are much more complex.

“We went in with a somewhat simplistic view,” Cole Barton, an ecologist at the University of British Columbia in Canada, told the New York Times. “You know, people stop, animals will breathe a sigh of relief and move more naturally. And what we saw was very different,” he said.

The new study, published in Nature Ecology & Evolution, is based on data from 102 animal camera monitoring projects in 21 countries in North America, Europe, South America, Africa and Asia.

The cameras, which automatically take pictures of wildlife when they detect movement and body heat, have become essential research tools for wildlife biologists.

The data allowed the scientists to study the activity patterns of 163 different species of wild mammals and track how often humans appeared in the same locations.

The study provides a very complex picture of scientists trying to understand what has been called the “anthropopause”, when the pandemic radically changed human behavior.

“There is no one-size-fits-all solution when it comes to mitigating the impacts of human activity on wildlife,” said Caitlin Gaynor, an ecologist at the University of British Columbia. “Because we see that not all species respond similarly to humans.”

During the pandemic, human activity decreased in some of its locations while increasing in others. At each study site, the researchers compared how often wild animals were detected during a period of high human activity and a period of low human activity, regardless of whether the reduced activity came during the quarantine period.

Carnivores, such as wolves, appeared to be particularly sensitive to humans, showing a greater drop in activity when human activity increased.

“Carnivores, especially larger carnivores, have this long history of, you might say, competition with humans,” Dr Barton said. “The consequences for a sarcophagus bumping into people or getting too close to people often means death.”

On the other hand, the activity of large herbivores such as deer and elk increased when people were out and about. This may be because the animals simply had to move more to avoid crowds of people. But if people help keep carnivores away, it could also make it safer for herbivores to come out and play.

“Herbivores tend to be less afraid of humans and may actually use them as a shield than carnivores,” said Dr Marlee Tucker of Radboud University Nijmegen in the Netherlands.

“We are much more tolerant of a possum in our yard than a bear in our yard”

Location also mattered. In rural and undeveloped areas, where the landscape had not been greatly modified by humans, animals generally became less active as human activity increased. But in cities and other developed areas, wild mammals tended to become more active when humans did.

“It was a bit contradictory and strange,” said Dr. Gaynor. “We had a closer look and a lot of this activity was actually happening at night. The animals were becoming more nocturnal.” The researchers suggest that several phenomena could underpin these trends. Perhaps the species and individuals that have persisted in these landscapes are those that are most tolerant and common to humans.

Animals that did not “escape” may be attracted to human resources, such as food and garbage, and become more active when these resources are abundant, but shift their foraging missions to evening hours to reduce the chance of encountering humans.

“This appears to be an adaptation of animals to coexist with humans,” said Dr. Barton. “For their part, the animals do everything they can to coexist.”

However, there were exceptions. In more developed places, large omnivores, such as bears and wild boars, were found less often when human activity increased. Although they are also attracted to human resources, including garbage cans and fruit trees, it may simply be too dangerous for large animals to hunt these goods when there are many people.

“We’re much more tolerant of a possum in our yard than a bear in our yard,” Dr. Gaynor said. Many studies of human impacts on wildlife focus on a small number of species and locations, but teasing out some of these general patterns is a real contribution to the scientific literature, said Jerrold Belant, of Michigan State University.