On a typical spring, breeding seabirds – and human seabird watchers – flock to the island of Stora Karlsø on the Swedish coast.

But in the year In 2020, the covid-19 outbreak canceled the tourist season and the population of the island decreased by more than 90 percent. Out of the picture, the white-tailed vultures came in, more numerous than usual. Researchers found.

It may seem like a clear example of how nature can be saved when people disappear from the landscape – if ecosystems are not complex. A large number of vultures hung the little birds from their ledges and occasionally climbed the cliffs where they laid their eggs.

In the chaos, some eggs fell from the cliff; While the killings were far away, others were abducted by hunters. Jonas Hentati-Sandberg, a marine ecologist at the Swedish University of Agricultural Sciences, found that the reproductive performance of murres dropped by 26 percent. “They were flying in panic, and they lost their eggs,” he said.

The plague was, and still is, a global human tragedy. But it has also happened to ecologists Unparalleled opportunity To learn more about how humans affect the natural world by documenting what happens when we suddenly step outside.

A growing body of literature paints a complex picture of the decline of human activity in the so-called “anthroposes.” Some species have benefited from our absence, in line with earlier media narratives that nature was the ultimate healer without panicking. But Other species have struggled Without human protection or wealth.

“Humans are playing this dual role,” says Amanda Bates, a marine conservation scientist at the University of Victoria in Canada. We are “threats to wildlife but guardians of our environment,” she said.

The study has important lessons for conservation, the scientists say, suggesting that even modest changes in human behavior can be beneficial to other species. Those changes are especially important to consider as the human world comes back to life and summer travel increases. Able to generate “Anthropols”. Vigorous movement.

“A lot of people feel like they want to get on top of their lives on vacation, on business trips,” Christian Roots said. A behavioral ecologist at the University of St. Andrews introduced the concept of “anthropologies” in a recent paper. (He and Dr. Bates were also part of the team that created “Anthropouse.”)

“Humans should travel and enjoy nature,” he added. But I still think it can be very subtle changes in the way we do things that have a big impact.

Many people’s daily activities came to an abrupt halt when the pandemic hit. April 5, 2020 – The peak of the pandemic lockdown – 4.4 billion people, or 57 percent of the planet, were under certain movement restrictions; Scientists speculate. Driving is down more than 40 percent and air traffic is down 75 percent.

These sudden changes allow researchers to distinguish the effects of human travel from other ways we shape the lives of other species.

“We know that humans affect ecosystems by changing the climate, by changing land use, such as demolishing homes and building shopping malls,” said Christopher Wilmers, a wildlife ecologist in Santa Cruz, California. “But this kind of shakes all that up, and you say, ‘Oh, well, what’s the impact of human activity itself?’ He says.

People dig in their homes—cars stuck in garages, airplanes in hangars, ships on docks— Air And Water quality It has improved in some places, scientists have found. No more noise pollution. on the floor And Under the sea. Habitats disturbed by man He began to recover.

In March 2020, Hawaii’s Hanama Bay Nature Reserve, a popular snorkeling destination, was closed for nine months. “The outbreak has reset the visitor impact to zero,” said Kuulei Rogers, a coral reef ecologist at the Hawaii Institute of Marine Biology.

Swimmers without sediment kick, water clarity It improved by 56 percent., Dr. Rogers and her colleagues attended. Fish density, biomass, and diversity have increased in areas previously depleted by predators.

Indeed, scientists have found that many species have moved into new habitats as epidemic outbreaks have changed. Ecologists sometimes call it “the aspect of fear.”

“All animals are, you know, trying not to die,” says Caitlin Gaynor, an ecologist at the University of British Columbia. That drive to survive drives them away from potential predators, including humans. “We are noisy and novel and we look like their prey – and in many cases they are the prey,” Dr Gaynor said.

For example, mountain lions in the Santa Cruz Mountains of California tend to avoid cities. But after local shelter-in-place orders go into effect in 2020, animals The probability of choosing a place to live became high Near the outskirts of the city, Dr. Wilmers and his colleagues were found.

Dr. Wilmers said mountain lions are responding to changes in the urban soundscape, which is typically filled with human chatter and the screeching of passing cars. But as soon as those sound stimuli were gone, the animals were like, ‘Well, they might have gone to see if there’s something to eat here,'” he said.

Just north, in newly quiet San Francisco, white-crowned sparrows He began to sing more quietlyBut the researchers found that the distance they could communicate “more than doubled.”

The birds started singing at lower frequencies, a change associated with better performance – and the ability to defend territory and protect mates. “Their songs were more ‘sexy,'” said Elizabeth Derryberry, a behavioral ecologist at the University of Tennessee, Knoxville, and co-author of the study.

“And it was night,” she added. “Which kind of gives you hope that if you reduce the volume of noise in the environment, you can immediately have a positive effect.”

But the effects of human absence varied in type, space, and time.

Several studies have found that. As the traffic eased In spring 2020, The number of wild animals They were. He was killed by a car He refused. But the number of wildlife and vehicle collisions recently He sneaked back outAlthough traffic flows are below normal levels, a research team reports.

“During the one-mile drive epidemic, there were many accidents that we interpreted as changes in animal habitat use,” said Joel Abraham, a graduate student in ecology at Princeton University and the study’s author. “Animals started using roads. And even when the traffic started, it was hard to stop.

The locks seem to encourage some invasive species. Increase daily activity Eastern cottontail rabbits in Italy are thwarting efforts to control others, where their rapid expansion threatens native species. For example, the epidemic A long-planned project has been delayed To eradicate giant, predatory rats from Gow Island, a critical habitat for seabirds in the South Atlantic.

The rats that came with the sailors of the 19th century would attack and feed on live bird chicks, often leaving large wounds. “I’ve nicknamed them ‘vampire rats’,” says Stephanie Martin, environment and conservation policy officer for Tristan da Cunha, of which Gow Island is a part. Many chicks succumb to their injuries.

Scientists were ready to launch a major mouse-eradication effort when the outbreak hit, delaying the project for a year. In the breeding season between them, it is still prevalent with vampire rats, not one. Magillivray prion chick. – An endangered bird that only breeds on owls – survived. “We’ve lost another breeding season,” Ms. Martin said. “It means another year without kids.”

Another example of human dual roles: the mice are only on Gog because humans took them there. “But now we absolutely want people to eradicate them,” Dr. Bates said.

These kinds of effects are compounded all over the world, she said. Protection, Education And follow up Programs are interrupted or Funding is prohibited. He takes it in. Hunting wild animals And Persecutionas well as Illegal logging and miningIt has been reported in many countries.

Economic instability may have spurred some of the activity, but experts believe it’s also due to a lack of human resources, including reduced staffing and conservation in parks. Absence of touristswhose presence would normally discourage illegal activities.

“We’re not entirely bad people,” says Mitra Nico, a research assistant at the University of Victoria. We are doing more good than we give ourselves credit for.

As people continue their normal activities, researchers continue to monitor wildlife and ecosystems. If an ecosystem that seems to have benefited from human extinction suffers when humans return to flood, that would be even stronger evidence of our impact.

“This reversal of experimental or quasi-experimental interventions allows for scientifically robust insights into how environmental processes work,” said Dr. Roots.

Understanding these mechanisms can help practitioners design programs and policies that more thoughtfully convey our impact.

Carlos Duarte, a marine ecologist at the King Abdullah University of Science and Technology, said: “If we strengthen our role as guardians and continue to manage pressures, we can tilt humanity’s role in the environment to a much more positive one.” in Saudi Arabia.

For example, a team of researchers found loggerhead sea turtles living with vacationers on the Greek island of Zakynthos during the summer of 2020. They spent a lot of time near the beach In the warm water that is suitable for the development of female eggs from previous years.

The results suggest that tourists are driving sea turtles into colder waters, slowing egg development and reducing egg production, causing the animals to hibernate for a shorter period of time, said Gail Schofield, a conservation ecologist at Queen Mary University. London and the author of the study.

“It’s a very narrow window of opportunity,” she said.

She admits that it is impossible to stop all tourism. But designating a stretch of beach as protected turtle habitat and banning swimming in early summer could be an important refuge for the animals, she said.

When the Hanauma Bay Nature Preserve reopens in December 2020, it has set a strict new limit on daily visitors. It is now closed two days a week, up from a week before the outbreak, Dr. Rogers said.

Other changes could also pay dividends, experts said: construction Wildlife crossings on highways It may prevent some animals from becoming roadkill, but quieter car engines and boat wheels may curb noise pollution on land and at sea.

“No longer can anyone say we can’t change the whole world in one year, because we can,” Dr. Bates said. “We did.”

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