RIO DE JANEIRO — It's not easy being a baby sea turtle, hatching into a human's world. Curious children, leashless dogs, oblivious joggers: The dangers are many. Some never complete their postnatal dash to the ocean.

But in recent days, environmentalist Herbert Andrade has watched hundreds of baby turtles mosey their way toward the water along Brazil’s northeast coast, unmolested by people or pets, unencumbered by anxiety. The beach is empty. People, fearful of catching and spreading the coronavirus, are inside. But outside, Andrade sees a natural world blooming.

“The whole world is under risk,” said Andrade, environmental manager for the city of Paulista. “But this was a moment of happiness. It was a feeling that nature was transforming itself.”

For centuries, humans have pushed wildlife into smaller and smaller corners of the planet. But now, with billions in isolation and city streets emptied, nature is pushing back. Wild boar have descended onto the streets of Barcelona. Mountain goats have overtaken a town in Wales. Whales are chugging into Mediterranean shipping lanes. And turtles are finally getting some peace.

While some stories of animal invasion that have gone viral have been fake — turns out elephants didn’t get drunk on Chinese corn wine and pass out in a tea garden — the apparent resiliency of the natural world is leavening a global tragedy with brief moments of wonderment. For people. And, apparently, for animals, too.

“The goats absolutely love it,” said Andrew Stuart, a resident of Llandudno, Wales. He saw the goats stroll into town one recent night, and has watched since then as they’ve availed themselves of its offerings. They’ve munched on windowsill flowers. Convened in parking lots. Strutted down emptied streets.

“They keep coming back, multiple times per day, 10 to 15 of them,” he said. “They’re taking the town back. It’s now theirs. Nothing is stopping them.”

But beyond the short-term benefits that human quarantines have brought the animal kingdom, conservationists say the pandemic could be an opportunity to push for more environmental protections and create a safer world for animals. An infrequently uttered word is beginning to sneak into conversations among conservationists and animal rights activists.

“I am hopeful,” anthropologist Jane Goodall told The Washington Post. “I am. I lived through World War II. By the time you get to 86, you realize that we can overcome these things. One day we will be better people, more responsible in our attitudes toward nature.”

A growing body of research has suggested that the risk of emerging diseases, three-quarters of which come from animals, is exacerbated by deforestation, hunting and the global wildlife trade, particularly in exotic or endangered species. One of the major vehicles for the transmission of novel diseases from animals to humans are wildlife markets, in which exotic animals are kept in cramped and unsanitary conditions. They have been linked to both severe acute respiratory syndrome (SARS) and covid-19, the disease caused by the new coronavirus.

Now countries around the world are under growing pressure to act. China, whose insatiable demand for animal parts drives much of the global wildlife trade, has taken the extraordinary step of banning the consumption of wild animals, and may do the same for dogs. Vietnam, another country with a large demand for animal products, said it intends to follow suit.

The U.N. biodiversity chief has called for a global ban on wildlife markets. So have 60 members of the U.S. Congress. More than 200 of the world’s leading conservation groups have asked the World Health Organization to take action against the wildlife trade. A World Wildlife Fund survey of 5,000 people in Hong Kong and Southeast Asia found 90 percent supported government closures of unregulated wildlife markets.

“Humans are extraordinarily selfish,” said Vanda Felbab-Brown, a Brookings Institution scholar who studies wildlife trafficking. “If they start dying, they will start taking actions to minimize their dying. The most impactful and consequential legislation always comes after the health risks.”

The impacts of the closures and crackdowns, if they persist, will be global, undercutting the demand that fuels illegal wildlife trafficking, an illicit trade valued at more than $23 billion annually. The ripple effects of enforcement in Asia could be felt as far away as Latin America, where jaguars and turtles are hunted and killed to meet demand in China.

“Asian traders call it the Latin tiger,” Felbab-Brown said. “They are using jaguar bones and teeth to produce elixirs. . . . It’s picked up a lot in Latin America.”

But analysts say the pandemic also heightens potential dangers for animals. Poverty and hunger, exacerbated by lockdowns and disruptions in food supplies, may drive more people to hunt.

“And that’s okay,” said Joe Walston, a senior official with the Wildlife Conservation Society. “If people are put in a position of poverty, and we have failed providing economic alternatives, they should be able to do that.”

More concerning, advocates say, is the possibility that people could abandon their pets, out of the mistaken fear they can spread the virus, or because they can no longer afford to feed them.

“It is more likely to increase pet abandonment,” said Marco Ciampi, president of Brazil’s Humanitarian Association of Animal Protection and Well-Being. “And the fake news is terrible. But even with this, animals will be in a more safe position, if we listen to the call of animals: ‘We are here, and if the environment is friendly, we are friendly, too.’ ”

“It’s an amazingly magical moment,” he said. “There are peacocks in the streets.”

Bruce Borowsky, a videographer in Boulder, Colo., was walking through the main pedestrian strip of the college town last week when he experienced that magical moment. Up near the top of a tree, beside a building, he spotted a mountain lion, asleep, back paws hanging down. Down below, Pearl Street, which normally teems with restaurant patrons, shoppers, and University of Colorado students, was a “ghost town.” Nothing was waking up the mountain lion anytime soon.

“I’ve lived in Boulder for 30 years, and I’ve never seen a mountain lion before,” Borowsky said. “And I’m a filmmaker and am outdoors constantly. Animals are sensing that people aren’t around much and are coming out more.

“We’re waiting for the bears to come out of hibernation and see how brazen they get.”

Along Brazil’s northeastern shoreline, Andrade is also seeing sights he has never witnessed. He has cared for endangered sea turtles for more than a decade, and has seen all sorts of calamities befall them. Artificial light along the beach especially confuses the turtles. They mistake it for the water’s reflection, wander off toward it and die along the way.

“For every thousand,” he said, “only one or two reach adulthood.”

For years, he has tried to teach people about the fragility of baby sea turtles — an ongoing effort he compared to a boxing match. He has erected protective areas around their nests. He has held events to show children why they’re special. Life was getting better, safer for turtles. But nothing compared to this: an empty beach.

For him, the beauty of it ached.

“It was a surreal sensation,” he said. “You see nature living out its role in this way. . . . Things fit together. We saw nature birthed without human interaction.”