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Why bears know when it is garbage day, Coyote Learned to look both ways before crossing the road, and Raccoons can solve Open the bungee cord.
At first glance, this is a scene that plays out every day in cities across the United States.
A USPS attendant wearing a royal blue bucket hat stepped out of the mail truck and strode across the street with a letter in his hand.
But the postman either didn't notice or didn't seem to care that a huge American black bear, probably a young male, was sitting on his rump a few yards away, scratching at his shed winter coat.
Immediately to the left, Interstate 240 roars behind chain-link fence , apparently just white noise to the bears, eventually sloping down the sidewalk and deeper into the neighborhood.
Along the highway in suburban North Carolina, a team of researchers studying bears was fascinated by another discovery, a deep cavity inside a gnarled silver maple tree.
Bear, one of more than a hundred bears tracked in the study, was a radio-collared female where she hibernated despite the constant flow of traffic just feet away.
The project is now in its eighth year, but "These projects still amaze me" , the state's black bear and furbearer biologist, holds the ladder steady as a colleague climbs a tree There was a scramble within to measure the nest.
It was the largest tree nest she had ever seen when she was 23 years old and studying black bears. "They're much more adaptable than we thought."
In fact, it's hard to imagine black bears adapting so well to life in Asheville.
In this progressive city of about 95,000 people nestled in the Blue Ridge Mountains, bears shuffle down residential streets in broad daylight and climb onto people's decks and front porches.
Some Ashevillians have embraced their bear neighbors, and nearly everyone you talk to has a video of their most recent bear encounter on their phone.
The emergence of urban bears in Asheville and elsewhere stems from a combination of trends, including changes in land use and the alluring buffet available in close proximity to where people live.
These factors have increased the black bear population in North America to nearly 800,000.
Meanwhile, sprawling cities and suburbs have devoured large swathes of bear habitat, leaving the animals no choice but to adapt to living with their human neighbors.
This phenomenon occurs in urban areas across the United States and around the world, and is not unique to black bears.
Many mammals that eat a variety of foods are moving in and changing their behavior as they learn urban survival skills.
As more and more scientists study the creatures right under their noses, a consistent message is emerging: Many species are adapting to urban life in unprecedented ways.
Coyote will look before crossing the road.
Black Bear knows when it's garbage day.
A raccoon figured out how to pull a bungee cord out of a trash can.
A 2020 review of 83 urban wildlife studies across six continents in the United States found that up to 93% of urban mammals behave differently from their rural counterparts.
Most of these animals, such as European rabbits, wild boar, rhesus monkeys and beech martens, become active at night to avoid people.
They have also expanded their natural diet to include human food and reduced their home range to smaller areas.
The more we know about the animals that live among us, the better we will get along with these urban newcomers, ecologists say.
Behind a fast-food restaurant and hotel in Asheville, Jennifer Struth and two colleagues dragged a culvert trap, a barrel-shaped steel cage used to catch black bears, to a spot near the hotel parking lot.
They hope to capture a female bear with three cubs in the area.
Ph.D. in Fisheries, Wildlife and Conservation Biology A student at North Carolina State University opened a freshly finished box of baked goods, which was irresistible for an animal with a nose sharper than a hunting dog's. bait.
The team spread cake frosting on the sides of the trap and put in some donuts and cinnamon rolls .
Scientists will anesthetize a previously captured female bear and replace its radio collar if their prey is trapped.
The first phase of a bear study in an urban suburb led by wildlife biologist Nicholas Gould revealed interesting differences between urban and rural bears using data from more than 100 radio-collared bears. .
Female urban bears weigh nearly twice as much as their rural counterparts when they are one to one and a half years old.
Some two-year-old urban female bears have given birth to cubs, but none of the rural bears of the same age have reproduced.
However, in the four-year study, 40 percent of urban bear deaths occurred, with vehicle strikes being the leading cause.
Researchers say it's unclear at this stage whether urban living is good or bad for Asheville's environment.
Other studies paint a less ambiguous picture.
Like the bears in Asheville, urban bears in Durango, Colorado, and Aspen, and urban bears in Lake Tahoe, Nevada, are heavier and have more cubs, but few of their cubs survive. , resulting in a net population decline.
Seeing a fat bear with a bunch of cubs might give the impression that urban development and suburban sprawl are good for animals, but the reality is different.
In 2020, a female bear protecting her cubs attacked Valerie Patenotte's dog, who later died.
"We know everyone has to coexist," Paternot said as we stood on her back deck overlooking the mountains in the distance.
"We just want to give the pandas more space."
As if to suggest, a family of bears appears below us.
One cub climbed a tree; the other jumped and talked, and it looked at us warily.
An experiment is being planned to find out how residents can coexist safely with their feral neighbors.
Two communities will be part of an upcoming nationwide initiative to encourage consensus practices such as leashing pets, securing litter, removing bird feeders and not approaching or feeding animals.
Two other communities will receive educational materials and serve as experimental controls.
By tracking radio collars in all four communities, they hope to learn whether promoting best practices will change residents' behavior and reduce the number of nuisance reports.
In Durango , researchers went a step further and distributed more than a thousand bear-resistant trash cans.
Households using outlets experience 60% fewer problems.
But some people want bears in their backyards, especially Janice Hussebo, who considers them part of her family.
2 For years, she attracted hungry bears to the deck of her home northeast of downtown Asheville, where they helped themselves to birdseed.
"I have friends who call me the bear whisperer," as we huddled in her doorway, watching a mother bear and her twin cubs wander around the porch.
"Let her lie here taking care of her cubs while I talk to her..." she said, her voice trailing off with emotion.
But wildlife officials warn that feeding bears can reduce tolerance for the animals by increasing the risk of conflict and injury, two reasons local county ordinances ban the practice.
While black bears have retreated to about half of their former range and now live in about 40 states, coyotes native to the Great Plains have swept across the United States in recent decades.
They can now be found in every state except Hawaii and most major cities.
The metropolis most similar to urban coyotes is Chicago, which is home to as many as 4,000 of the animals.
began studying coyotes in Chicago in 2000, shortly after the animals began to appear.
At that time, Geert thought his project would last a year.
More than twenty years later, he is still persisting.
"We have always underestimated this animal's ability to adjust and adapt," Geert said.
"They push the boundaries of what we think of as limitations."
On a spring morning in suburban Chicago, three researchers trudged through the swamp behind a residential neighborhood.
They are looking for the den and pups of radio-collared female coyote 581.
Suddenly, the scream of a "puppy" pierced the hum of highway traffic.
The group spread out, making their way through the cattails and peeking into caves on the hillside.
A moment later, Senior Field Technician Lauren Ross shouted.
She found a several-week-old "puppy" sitting in the tall grass, its pale belly still swollen from its mother's milk.
Ross gently lifted the young male and examined him, pulling out a section of hair for genetic analysis and inserting a small microchip called a pit tag between his shoulder blades.
The chubby "puppy" was quiet and motionless during the exam.
Rose said once the team left, her mother would come back to pick it up.
At the beginning of Geert's research, he thought coyotes would be restricted to parks and green spaces, but he was wrong.
"Now we have coyotes everywhere, in every neighborhood, every suburban city and downtown."
In fact, despite our best efforts to eradicate them, coyotes have managed to survive.
At least 400,000 wolves are killed each year, approximately 80,000 of them by federal predator control programs primarily in the West.
Vehicle strikes are the leading cause of death for coyotes in Chicago, but the animals have learned to avoid cars and can even read traffic lights.
Adding to their adaptability is their flexible diet.
Coyotes will eat just about anything, from shoe leather to fruit (they can climb fruit trees).
It stands to reason that coyotes living in green spaces in metropolitan areas will eat mostly natural foods, such as rabbits and rodents, while coyotes living in urban centers will rely on human food, including garbage and household pets.
But often this is not the case, "Variability is the dominant mode."
Coyotes can make a living almost anywhere.
But are they genetically built for urban life, or are they quickly adapting, in their classic sly fashion?
It could be a hybrid, say urban ecologists at the University of California, Berkeley, where coyotes can take advantage of their inherent ability to adapt to new environments while becoming better at living in them over time.
"Coyote is like an artificial intelligence system that learns faster than humans can create it and takes over the world," Schell joked.
For example, they will compare a group of coyotes who ate a SimCity diet ( high in carbohydrates and sugar) with those who ate a Coyote on a more natural, high-protein diet.
Their hypothesis, which is supported by some anecdotal evidence, is that coyotes that eat human food will become bolder around people.
"We follow the old adage 'You are what you eat,'" Schell said.
He speculates that coyotes that eat processed grains, for example, will be hungrier and search for food more frequently than coyotes that eat rabbit for breakfast.
Although no such link was found among Chicago coyotes, he noted that reliance on human food does lead to more conflicts with people and pets by reducing canines' fear of people.
In some places, such as Southern California , 38% of urban coyotes' diet consists of human food sources.
Like coyotes and bears, raccoons are expanding into North American cities.
In Washington, D.C., wildlife researchers wanted to know whether raccoons living in cities were bolder and more risk-taking than those in rural areas.
They measured this by watching raccoons prepare to investigate an unfamiliar object, in this case a bait buried in a square log.
Researchers installed more than a hundred automated cameras in urban and rural areas of neighboring Virginia .
On a sultry September morning in Fort Totten, Gallo laid out smelly baits, which he called "dead animals in jars," while Ritzell tied a camera to a nearby tree.
She will come back in two weeks to see which animals made it through.
She showed me her favorite video to date, of an aggressive raccoon chasing a fox.
A few months later, data showed that urban raccoons were more exploratory than rural raccoons, requiring more time to investigate.
Urban raccoons are also more sociable, travel more often in pairs and are more territorial than their rural counterparts, suggesting that urban raccoons are adjusting their behavior to adapt to city life.
The next goal is "to determine whether there have been any evolutionary changes" .
When zoologist Sarah Benson-Amram first began studying raccoon behavior and cognition, she thought such a common species would be thoroughly studied.
After all, the furry omnivore is a pop culture icon, nicknamed the "trash panda."
Instead, I was shocked to find almost nothing in the scientific literature.
Some researchers have tried to study these intelligent animals but gave up when their subjects kept running out of their cages.
She said her research so far confirms raccoons' reputation for being cunning.
In an experiment called reversal learning, raccoons, coyotes and skunks were shown a box containing a button or foot pedal that, when pressed, would release food.
After the animals figured out how to get food, the researchers switched buttons and pedals, forcing them to adjust their strategies.
Most of the raccoons solved the problem on the first night, and only one of the six coyotes made contact with the box.
Once a coyote becomes comfortable with objects, it can win prizes like raccoons and skunks.
Benson Amram, now at the University of British Columbia in Vancouver, said urban coyotes have different survival strategies than raccoons.
"They succeed by avoiding humans rather than exploiting them."
Research supports the theory that some urban mammals rely on their cognitive abilities to adapt to city life, and when they encounter obstacles, they can Innovate on the spot.
a behavioral neuroscientist at the University of Richmond, she found that innovators have more specialized nerve cells in their hippocampus , the center of learning and memory.
"It was a surprise to me," said Lambert, whose research also found that raccoon brains are more like primates than any other species.
But as is the case with coyotes and many other urban animals, more research is needed to determine whether raccoons are evolving to be smarter.
Nonetheless, it is intriguing that our efforts to deter raccoons may be fueling an innovation arms race.
"It's possible that we are actually creating smarter animals," she said, "because we are giving them increasingly difficult problems to solve."
Until recently, urban wildlife was in scientific research Mostly ignored.
This is partly because these species are considered "pests" that don't deserve our attention, or are not wild animals at all.
“We live on a rapidly urbanizing planet and we would be foolish not to care about animals in our urban landscapes” Seth Mager Director of the Urban Wildlife Institute at Chicago’s Lincoln Park Zoo “Whether we like it or not Like, we all live with wildlife."
While much of urban ecology focuses on minimizing conflict, we forget that our experiences with wildlife are often enjoyable.
“Another part of living with animals is about celebrating these moments.”
My moment was a summer morning at Park Golf Course in Washington, DC.
I walked the back nine of the Downs with a group of biologists, looking for coyote scat, or scat.
When we reached the top of the mountain, we were surprised to see a coyote and "puppy" standing below us.
We looked at each other in surprise.
The adult coyote, his back golden in the sun, remained motionless as the puppies scampered around.
A few seconds later, the big coyote quietly slipped into the nearby woods. The little guy slumped down and took one last look before disappearing into the shadows.
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