Animals in national parks are exposed to even a few people

People often visit US national parks to see wildlife. But how does our presence affect the animals we hope to see?

National park traffic has grown steadily over the past decade, and popular parks like Yosemite and Yellowstone can easily see more than a million visitors a year. In these intensively used areas, animals can be expected to change their behavior to avoid humans.

But a new study led by the University of Washington found that even in remote, rarely visited national parks, the presence of even a few people affects activities living nature that live there. The study found that almost any level of human activity in a protected area, such as a national park, can change animal behavior. The study was published on October 13 in the journal People and nature.

“There is a growing recognition of how simply the presence of humans in these places and our recreation there can affect wildlife,” said senior author Laura Proux, an assistant professor in the UW School of Environmental and Forest Sciences. “These results are impressive, showing that in fact any level of human activity can have an impact on wildlife.”

The research team based their study in Glacier Bay National Park, a coastal zone in Southeast Alaska, accessible only by boat or plane. Most visitors arrive on cruise ships, but the boats do not dock at the shore, and there is very little human traffic in the park. Because so few people visit each year — only about 40,000, but growing — the park was an ideal place to conduct this research, Proux explained.

“Glacer Bay is a great park to explore the lower limits of where humans are beginning to influence wildlife behavior,” Prugh said.

The researchers worked with national park officials to design and implement an experiment that compared wildlife activity in areas frequently used by humans with areas where humans were absent. They installed 40 motion-activated cameras at 10 sites to record human detection and four kind of animals– wolves, black bears, brown bears and moose – in two summers. By controlling where and when people can access certain areas of Glacier Bay, and then measuring the wildlife’s response to different levels of human activity, the researchers identified two important thresholds.

First, when humans were present in the area, the cameras detected fewer than five animals per week in all four species studied. In most cases, this probably meant that the animals avoided places where humans were present. Second, in remote areas, wildlife detection decreased to zero each week once outdoor recreation levels reached the equivalent of about 40 visitors per week.

The researchers were surprised by the apparent low tolerance of wildlife to the presence of humans nearby.

“It was fascinating to see the number of wildlife sightings that we are ‘missing’ by simply restoring backcountry areas of Glacier Bay,” said lead author Mira Sytsma, who completed the work as a UW graduate student. “I was surprised that for all four species, wildlife sightings were always highest when there was no human activity. So many people visit national parks for the chance to see wildlife, and the desire alone can reduce the likelihood of that.”

Although all four species showed some variation in activity due to humans, wolves were more likely to disappear from cameras when humans were present. Brown bears are the least affected by human presence. However, moose were more active at that time of day and in places where people were seen. Researchers hypothesize that moose may use humans as a protective shield against predators, choosing to coordinate their activity hours with humans to avoid becoming prey.

The researchers expect that in parks where animals are more accustomed to seeing people, at least some individual animals will not react as strongly to humans as they do in Glacier Bay. But the findings do shed light on what is likely happening in national parks and wilderness areas across the country: More people are visiting these areas than ever before, and the presence of people almost certainly affects the behavior of the animals that live there.

“I would expect similar results to be found in other national parks, especially those with relatively low attendance. I wouldn’t be surprised if more and more people are looking for the less popular ones national parks research that will have interesting and important implications for park and wildlife management,” Sytsma said.

National parks and desert not just seeing more visitors in high season. More people are choosing road systems at less busy times to avoid the crowds. Additionally, some parks are expanding their trail network to accommodate more visitors.

The authors hope that this study can help park managers consider different approaches to making parks accessible to both people and animals. For example, managers could consider concentrating tracks and human use in certain areas to reduce their overall footprint, or impose restrictions on the time of year or days people can visit.

“Our findings confirm the concentration of human activity in some areas, because if you’re going to go above zero human activity and have an impact, you can also go well above zero in some areas and then have other areas where you have almost no human activity. activities,” Proux said. “So in these areas, wildlife can live their natural lives without the influence of humans.”

Co-authors are UW’s Beth Gardner and Tanya Lewis of Glacier Bay National Park and Preserve.

Additional information:
Low levels of outdoor recreation are changing the behavior of wildlife, People and nature (2022).