Eli Frankovich / Spokesperson Review
We have a problem people.
That was the message Laura Brugg received from US Park Service in Glacier Bay, Alaska, several years ago. To Broe, who studies human-wildlife interactions in the relatively crowded state of Washington, that claim seemed a bit exaggerated. After all, only 40,000 people visit the 3.2 million-acre park annually — ridiculously low numbers for anyone used to rebuilding in the Washington or Oregon Cascades, for example.
In fact, Glacier Bay is only accessible by boat or plane, and 94% of visitors come via cruise ships. However, park service employees have reported increasing numbers and wanted to know how – or if – this trend is affecting local wildlife. So Bruges, associate professor in the University of Washington’s School of Environmental and Forest Sciences, visited the site.
“I was shocked at the lack of people there,” she said. “And I thought ‘Wow, these guys really lost their perspective on what a lot of visitors are like.'”
However, she agreed to conduct the study. Over the course of two semesters, I collected images from 40 motion-activated cameras across 10 locations focusing on wolves, black bears, brown bears, and moose. I fully expected that you would find “little or no difference in animal activity between high-use and low-use sites”.
It was wrong.
In a study published this month, Bruges and her co-authors found that if humans were present, cameras spotted fewer than five animals per week in all four species studied. In most cases, this likely meant that the animals avoided areas where humans were. Second, in remote areas, wildlife spottings dropped to zero each week once outdoor recreation levels reached the equivalent of about 40 visitors per week. The researchers note that in some places where animals are more familiar with humans, the reaction to human presence is less.
While it’s just one study, in one place, the findings have implications for entertainment management, including in Washington.
“Our study suggests that if people wanted to recreate and reduce their impact on wildlife, it would actually be better to go on more crowded trails because these sites disturb the wildlife anyway,” she said. “I think, unfortunately, there’s a trade-off with human experience and the impact that has on wildlife.”
The question of how, or even whether, human outdoor recreation of unchallenged diversity affects wildlife is “sort of an emerging field,” Brogg said. Despite their young age, several studies of the recreational environment have shown that animals change their behavior in response to the presence of humans. Some mammals have become more nocturnal, abandoning their usual daily routines in the hope of avoiding human presence. In Montana, wolves and bighorn sheep avoid areas where skiers cut through the countryside. Another study showed that reindeer get away from skiers in remote areas for a longer time than from snowmobiles.
All this is well documented; Joel Berger, a professor at Colorado State University and author of Better Eat With: Fear in the Animal World.
He said the UW study is beginning to answer that question. Berger was not part of Brogg’s study and did not meet with her, though he said he was impressed with her research.
“Brog’s study provides the first quantitative evidence, in my impression, of the responses of wildlife species when exposed to people in these low-density situations,” he said.
It also showed variation in the species’ response to human activity, he said, noting that Brog’s study found that moose were more active if people were around, suggesting that large ungulates were using human presence as a shield against more cautious animals, such as wolves. This is known as the human shield hypothesis, a term coined by Berger.
“The question is, what does it take for animals to learn?” He said. “To be able to adopt an anti-harassment strategy to combat a predator.”
In addition to these questions, the study also raises a dilemma for leisure planners and outdoor enthusiasts, both in remote areas and in urban areas.
Implications for entertainment
The balance between recreation and wildlife is something that Spokane County park planner Paul Knowles thinks about often.
“As a land manager, you sacrifice some areas, in a sense, so that other areas can be devoted primarily to wildlife habitat,” he said.
When county planners design and build trails, they try to include “wildlife disturbance buffers.” These barriers are built using the best available science about how much alien species need humans. However, in an urban environment such as Spokane County, it is not always possible to include this space.
At least, Knowles said he’s heard “again and again” that once a property is acquired by the county and developed for recreation, wildlife viewing goes down.
“We have acquired these protected areas for multiple purposes and multiple benefits, including recreation,” he said. “So we have to find a way to balance those. It’s tough.”
That’s the biggest point, Brogg said. She has no desire or intent to tell people that they shouldn’t take a walk. But recreational scientists must realize that their activity – no matter how safe – affects wildlife.
“It’s not that people should stop entertaining,” she said. “But what is the best way to balance these trade-offs?”