It was 1998. Olivier Rubbers, then 29 years old, came up with the idea of returning beavers to his local rivers. “My level of knowledge about nature was extremely poor,” he now confesses. But he’d read a magazine article about how the beaver was indigenous to Belgium, though it had long been nearly extinct. Bringing beavers back, he thought, “would be a great project.” “Beaver bombing” or “beaver black ops” — as it’s become known in conservation circles — is the practice of illegally releasing the humble beaver into a waterway and leaving it to do what it does best: fell trees, build dams and construct lodges. Beavers are known as “ecosystem engineers,” or a “keystone species,” because they create an ideal habitat for all kinds of other wildlife. Rubbers borrowed his father’s car and drove to Germany to pick up the beavers, then crossed the border back into Belgium and dropped them in a river. Throughout 1999 and 2000, Rubbers repeated the feat with 97 more beavers, bringing them from Bavaria to Belgium in a van kitted out with homemade beaver crates. “We wanted them all,” he said. Rubbers and his accomplices soon learned that the best time to beaver-bomb was not at night but in the middle of the afternoon, preferably on a Sunday, when everyone was having lunch. He procured almost all the beavers from Gerhard Schwab, a wildlife manager based in Bavaria known as “the Pablo Escobar of beavers.” Over the years, Schwab has bred beavers and helped numerous communities across Europe with reintroductions — always in partnership with local wildlife management schemes. Rubbers showed Schwab some official-looking papers, all stamped and in French. Schwab had no idea that Rubbers was introducing the beavers into their new surroundings without local approval. “I had all the authorizations I needed,” Rubbers said. “Which, in my mind, meant no authorization.” “He bombs quite a bit,” Schwab admitted about Rubbers. “He wanted to do something for nature.” Rubbers was eventually fined 500 euros for detaining and transporting a protected species, although he told me that the local administration forgot to claim the money. He has spent the following years watching with satisfaction as the beavers spread across Belgium, transforming its waterways. Frogs and fish came to lay their spawn in the slowed, dammed-up water, while bugs and beetles thrived in the rotting wood of the felled trees. Birds followed in their wake, feeding off the fish and insects. “Belgium should thank me for services rendered to the nation,” Rubbers said. without asking permission first. It’s not just beavers: There are boar bombers, a “butterfly brigade” that breeds and releases rare species of butterfly and a clandestine group returning the pine marten — one of Britain’s rarest mammals — to British forests. Some, like Rubbers, have no background in conservation. Others have scientific credentials and feel an urgent need to restore nature’s ecosystems by taking matters into their own hands. The movement is facing backlash from farmers who don’t want wild animals wrecking their crops and a number of scientists who believe that the reintroduction process should be regulated and controlled. They say rogue rewilding is a crime, however you dress it up. The mavericks argue that the bigger crime is not to reintroduce keystone species in a biodiversity emergency. At the beginning of the 20th century, beavers were on the verge of extinction in Europe. They were hunted for their prized pelts and scent glands, and by 1900 there were just 1,200 left. Now, beavers are back from the brink, with the current European population estimated at about 1.5 million — and conservationists and rewilders agree that beaver bombers are partly to thank. Floods, wildfires and droughts have become multi-trillion-dollar problems in the 21st century, ravaging the landscape from Bangladesh to Belgium. As the world burns and biodiversity hits a crisis point, rewilding — the process of letting nature restore itself — can feel like a hopeful refuge. Beavers, ecologists say, may be part of the solution. The healthy wetland systems beavers create can sequester large amounts of carbon, according to climate scientists. Slowing down river flow helps the land act like a sponge, storing and holding more water, so it is more resilient to flooding and drought. “Beavers work for free, they work weekends, they work round the clock increasing the groundwater and being a motor for biodiversity,” Schwab said. “Some farmers and scientists say rogue rewilding is a crime, however you dress it up. The mavericks argue that the bigger crime is not to reintroduce keystone species in a biodiversity emergency.” In the U.S., after Oregon’s devastating forest fires in 2021, beaver wetlands remained green and lush, acting as natural firebreaks in the land. On aerial images of the charred landscape, the beaver’s habitat stands out, a wide and verdant ribbon running through the blackened trees. “I think beaver bombers are the heroes of our time,” said Ben Goldsmith, a British financier, writer and environmentalist who is a passionate supporter of rewilding. “A human lifetime is short — why should I not be the one that gets to see wildcats back on Dartmoor? Why should I not live in a country with beavers when they’re supposed to be there?” I asked Goldsmith if he’d participated in rogue reintroductions. “Had I been involved in beaver bombing more widely,” he said, “I don’t think I’d tell you.” Until last year, Goldsmith served as a director for the U.K.’s Department for Environment, Food and Rural Affairs. His older brother, Zac, is a former member of parliament and the U.K.’s current international environment minister. For ecologist and author Alex Morss, the fringe of the rewilding movement and its powerful backers are a problem. “Who cleans up the bill for illegal anonymous rogue rewilding if things go wrong?” she wrote to me in an email. Alongside a number of scientists working in ecology and conservation, Morss worries about the pitfalls ahead if people are encouraged to take matters into their own hands to address species loss. Maverick rewilding, she says, could increase the chances of conflicts between humans and wildlife, spread disease and actively harm biodiversity by introducing the wrong animals into the wrong environments. “There are also releasers who are skirting around the law or outright breaking it,” Morss added. “Or making decisions based on personal bias rather than ecological expertise, rather than lawful, professional and evidence-based conservation done carefully and less glamorously.” Beavers are capable of destroying valuable trees, eating crops and flooding farmland. In Tayside, Scotland, where beavers were illegally introduced around 2006, farmers shot the animals on sight. There was no law to stop the farmers from doing so because, although the beavers were endangered, they also weren’t officially there. It was, as one ecologist explained to me, a “wild west.” Morss said she welcomes “true” rewilding but is concerned that the movement is being co-opted by a privileged few who want to turn nature’s last refuges into “eco Disneyland.”

It was 1998. Olivier Rubbers, then 29 years old, came up with the idea of returning beavers to his local rivers. “My level of knowledge about nature was extremely poor,” he now confesses. But he’d read a magazine article about how the beaver was indigenous to Belgium, though it had long been nearly extinct. Bringing beavers back, he thought, “would be a great project.” “Beaver bombing” or “beaver black ops” — as it’s become known in conservation circles — is the practice of illegally releasing the humble beaver into a waterway and leaving it to do what it does best: fell trees, build dams and construct lodges. Beavers are known as “ecosystem engineers,” or a “keystone species,” because they create an ideal habitat for all kinds of other wildlife. Rubbers borrowed his father’s car and drove to Germany to pick up the beavers, then crossed the border back into Belgium and dropped them in a river. Throughout 1999 and 2000, Rubbers repeated the feat with 97 more beavers, bringing them from Bavaria to Belgium in a van kitted out with homemade beaver crates. “We wanted them all,” he said. Rubbers and his accomplices soon learned that the best time to beaver-bomb was not at night but in the middle of the afternoon, preferably on a Sunday, when everyone was having lunch. He procured almost all the beavers from Gerhard Schwab, a wildlife manager based in Bavaria known as “the Pablo Escobar of beavers.” Over the years, Schwab has bred beavers and helped numerous communities across Europe with reintroductions — always in partnership with local wildlife management schemes. Rubbers showed Schwab some official-looking papers, all stamped and in French. Schwab had no idea that Rubbers was introducing the beavers into their new surroundings without local approval. “I had all the authorizations I needed,” Rubbers said. “Which, in my mind, meant no authorization.” “He bombs quite a bit,” Schwab admitted about Rubbers. “He wanted to do something for nature.” Rubbers was eventually fined 500 euros for detaining and transporting a protected species, although he told me that the local administration forgot to claim the money. He has spent the following years watching with satisfaction as the beavers spread across Belgium, transforming its waterways. Frogs and fish came to lay their spawn in the slowed, dammed-up water, while bugs and beetles thrived in the rotting wood of the felled trees. Birds followed in their wake, feeding off the fish and insects. “Belgium should thank me for services rendered to the nation,” Rubbers said. without asking permission first. It’s not just beavers: There are boar bombers, a “butterfly brigade” that breeds and releases rare species of butterfly and a clandestine group returning the pine marten — one of Britain’s rarest mammals — to British forests. Some, like Rubbers, have no background in conservation. Others have scientific credentials and feel an urgent need to restore nature’s ecosystems by taking matters into their own hands. The movement is facing backlash from farmers who don’t want wild animals wrecking their crops and a number of scientists who believe that the reintroduction process should be regulated and controlled. They say rogue rewilding is a crime, however you dress it up. The mavericks argue that the bigger crime is not to reintroduce keystone species in a biodiversity emergency. At the beginning of the 20th century, beavers were on the verge of extinction in Europe. They were hunted for their prized pelts and scent glands, and by 1900 there were just 1,200 left. Now, beavers are back from the brink, with the current European population estimated at about 1.5 million — and conservationists and rewilders agree that beaver bombers are partly to thank. Floods, wildfires and droughts have become multi-trillion-dollar problems in the 21st century, ravaging the landscape from Bangladesh to Belgium. As the world burns and biodiversity hits a crisis point, rewilding — the process of letting nature restore itself — can feel like a hopeful refuge. Beavers, ecologists say, may be part of the solution. The healthy wetland systems beavers create can sequester large amounts of carbon, according to climate scientists. Slowing down river flow helps the land act like a sponge, storing and holding more water, so it is more resilient to flooding and drought. “Beavers work for free, they work weekends, they work round the clock increasing the groundwater and being a motor for biodiversity,” Schwab said. “Some farmers and scientists say rogue rewilding is a crime, however you dress it up. The mavericks argue that the bigger crime is not to reintroduce keystone species in a biodiversity emergency.” In the U.S., after Oregon’s devastating forest fires in 2021, beaver wetlands remained green and lush, acting as natural firebreaks in the land. On aerial images of the charred landscape, the beaver’s habitat stands out, a wide and verdant ribbon running through the blackened trees. “I think beaver bombers are the heroes of our time,” said Ben Goldsmith, a British financier, writer and environmentalist who is a passionate supporter of rewilding. “A human lifetime is short — why should I not be the one that gets to see wildcats back on Dartmoor? Why should I not live in a country with beavers when they’re supposed to be there?” I asked Goldsmith if he’d participated in rogue reintroductions. “Had I been involved in beaver bombing more widely,” he said, “I don’t think I’d tell you.” Until last year, Goldsmith served as a director for the U.K.’s Department for Environment, Food and Rural Affairs. His older brother, Zac, is a former member of parliament and the U.K.’s current international environment minister. For ecologist and author Alex Morss, the fringe of the rewilding movement and its powerful backers are a problem. “Who cleans up the bill for illegal anonymous rogue rewilding if things go wrong?” she wrote to me in an email. Alongside a number of scientists working in ecology and conservation, Morss worries about the pitfalls ahead if people are encouraged to take matters into their own hands to address species loss. Maverick rewilding, she says, could increase the chances of conflicts between humans and wildlife, spread disease and actively harm biodiversity by introducing the wrong animals into the wrong environments. “There are also releasers who are skirting around the law or outright breaking it,” Morss added. “Or making decisions based on personal bias rather than ecological expertise, rather than lawful, professional and evidence-based conservation done carefully and less glamorously.” Beavers are capable of destroying valuable trees, eating crops and flooding farmland. In Tayside, Scotland, where beavers were illegally introduced around 2006, farmers shot the animals on sight. There was no law to stop the farmers from doing so because, although the beavers were endangered, they also weren’t officially there. It was, as one ecologist explained to me, a “wild west.” Morss said she welcomes “true” rewilding but is concerned that the movement is being co-opted by a privileged few who want to turn nature’s last refuges into “eco Disneyland.”