'If we stop now, they're gone forever': The Nordic countries breeding Arctic foxes

Arctic foxes were almost hunted to extinction in Sweden, Norway and Finland. Can projects to breed and feed them help this native species return for good?

As summer gives way to an early autumn on the Norwegian alpine tundra and the wind howls over the fells, the Arctic foxes remain in their dens.

"They're not stupid", says biologist Craig Jackson as he chops up frozen dog food with a butcher's knife.

Jackson drops chunks of meat into buckets and, alongside his colleague Kristine Ulvund, walks past eight enclosures to deliver the animals their meal.

Sometimes, when the wind dies down, Jackson and Ulvund watch the young foxes frolic across the tundra, the animals unaware that the future of the Fennoscandian population rests on their fragile shoulders.

On this fell near Oppdal in Norway, 300km (190 miles) north of Oslo, the Norwegian Institute for Nature Research (Nina) has been breeding Arctic foxes in captivity since 2005. The programme, funded by the Norwegian government, forms the backbone of efforts to save the foxes in Fennoscandia, the Northern European peninsula which includes Finland, Norway, Sweden and part of Russia.

Inside a cabin, Jackson shows live images from a den on his computer screen. The foxes huddle together, like croissants in a breadbasket. This year, 34 pups have been born in the breeding station.

Come January, when the foxes will be around nine months old and ready to fend for themselves, Jackson and Ulvund will set them free. Over 18 years, 465 captive-bred foxes have been released at nine locations across Norway, where they're expected to bolster wild populations.

Equipped for temperatures below -40C (-40F), Arctic foxes have short muzzles, warm fur and insulated foot pads that act as heat exchangers. Historically, they lived across the Arctic's circumpolar tundra, including in Russia, Greenland, Canada, Sweden, Norway, Finland, Iceland and Arctic islands like Svalbard. In most of that range, they're still thriving.

But in Fennoscandia, the animal's prized pelt led to its near downfall. Intensive hunting pushed the Arctic foxes to the edge of extinction here by the early 20th Century. By the time legal protection was introduced in Sweden, Norway and Finland from the 1920s onwards, the damage had been done: populations were too small and fragmented to rebound. By 2000, just 40 to 60 Arctic foxes remained in Sweden and Norway. In Finland, none had been seen since 1996.

While the species is not threatened in other parts of its historic range, conservationists say it's important to save Fennoscandian Arctic foxes for their historic ecological role as a keystone species and their cultural significance to the region's identity.

In recent years, though, climate change has only worsened their plight, by disrupting the cycles of lemmings – small rodents on which foxes feed – and allowing the red fox to encroach on its habitat.

"Fennoscandian Arctic foxes heavily depend on lemmings," says Dorothée Ehrich, who studies the animals' interactions at the Climate-Ecological Observatory for Arctic Tundra (Coat) in Tromsø, Norway. In winter, lemmings dig tunnels through soft snow, nibbling on moss and willow branches. Climate change brings winter rain, forming icy layers in the snow and blocking their movement. In low lemming years, which are increasingly common, Arctic foxes don't reproduce.

That's why rangers now provide food for the foxes in more than 250 feeding stations across Norway, Sweden and Finland. In Kilpisjärvi, a small village near Finland's most northwestern point, Tuomo Ollila, a retired wildlife expert from state forest agency Metsähallitus, shows me a station.

"We give them dog food, premium quality only," he laughs. "In poor rodent years, it helps Arctic foxes survive in optimal breeding habitats." Although Arctic foxes still prefer lemmings, a 2020 study showed that supplemental feeding is particularly important for breeding pairs and their offspring.

Meanwhile, however, temperatures are rising, and humans leave food scraps all over the Arctic. These "anthropogenic subsidies" enable red foxes to move into tundra habitats. Larger, stronger and more aggressive than their Arctic cousins, they frequently outcompete them, prey on them and transmit diseases. To minimise this impact, local hunters as well as government-paid ones cull red foxes, especially near Arctic fox dens.

Both conservation measures are not without controversy. Supplemental feeding is typically a short-term solution. Critics of using it as a conversation strategy among any species argue that it should not be relied upon for years, as it can create dependency and interfere with natural behaviour. Culling red foxes, on the other hand, is particularly contentious because the species is native to the region.

Ecological alternatives exist to control red foxes. Large predators, like wolves and wolverines, could help, but their numbers are kept low. As Ulvund notes, "Sheep grazing high up in the mountains has strong political support in Norway." It makes a widespread return of large predators unlikely.

Experts agree that without human intervention, the Arctic fox might have already gone extinct in Fennoscandia. Thanks to the coordinated efforts, however, more than 550 now roam around the wild in Norway, Sweden and Finland. "Our data show that captive-bred foxes have the same survival and reproduction rates as the ones born in the wild", says Ulvund.

The population spilled over into Finland, where in 2022 the country's first litter in 26 years was born, 19km (12 miles) from a release site in Norway. "The coffee tasted great that morning," Ollila recalls.

Johan Fredrik Wallén remembers not seeing a single Arctic fox all summer during fieldwork in the Swedish tundra almost 20 years ago. "Now, we usually see them," he says. As a research assistant in Stockholm University's Arctic fox research group, Wallén coordinates the scientists and volunteers heading out each summer to conduct field studies on Arctic foxes in northern Sweden.

The work is tough, he says. "For weeks, you walk 15-20km [9-12 miles] daily, often off-trail, carrying everything on your back." The biggest challenge is the weather: it can be snowing, windy or cold. "I remember sometimes waking up in a tent covered in snow."

Fieldwork involves observing dens, looking for tracks, fur or scats, tagging pups, monitoring prey and competitors, and collecting behavioural and environmental data. Some seasons the researchers focus on studying microbiomes or capturing vocalisations.

It's not just tough, though: it's essential. Research helps assess whether measures are truly benefiting the Arctic foxes. The plans get tweaked accordingly. Captive-bred Arctic foxes were initially released in October or November, for example, but now remain in their enclosures over winter to build up fat reserves.

On northern Norway's Varanger Peninsula, where Ehrich does her research, red fox culling was the only measure in place for years. After two lemming peaks, Arctic fox numbers here increased to an estimated 21 in 2009 but then, in the absence of new lemming peaks, dwindled to just five in 2016. By 2017, says Ehrich, there were likely just two individuals left.

To prevent local extinction, 67 foxes from the breeding station near Oppdal were reintroduced, along with supplemental feeding. The population has since recovered. "Last year alone, over 90 pups were born on Varanger," Ehrich says. "People see them everywhere."

Releases bring risks, however, as introducing foxes from the same breeding lines can reduce genetic diversity and encourage inbreeding. Jackson says the initial target of Norway's breeding programme was cranking up the numbers across the country. "The only goal was to save the species," he says. Now the scientists pay more attention to improving genetics in wild populations with targeted releases.

Data shows it's working. Studies have noted an increased genetic variation within sub-populations in Norway and Sweden. Fewer differences between groups hints at movement across territories. But challenges persist. In Varanger, the released foxes came mostly from five breeding pairs. "So while there are many foxes now, we're considering releasing animals there again," says Jackson.

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The Arctic fox's revival stands as a success story of collaboration, not only bridging administration, conservation and research, but also uniting three countries behind a common cause. They set goals together, exchange information and alternate in compiling a joint annual report. "Biologists from different countries tend to work together well, even if they're not allowed to," says Wallén. "The difference here is that governments recognised that need, too. Animals don't see country borders."

It helps that the Arctic fox is not controversial. Ehrich calls it "the mainland little brother" of the polar bear, which is found in only on the Svalbard Archipelago in Norway, a group of islands off the mainland. "For many locals, [the Arctic fox] symbolises the intact Arctic nature," says Ehrich. Such positive associations makes conservation easy to explain to the public. "People working with large predators will tell you that's not always the case," Ehrich adds.

Yet, the scientists are reluctant to call their approach a model. "We can't rely on captive breeding to save a species," says Ulvund. "It should only be a last resort."

While numbers are rising, the Arctic fox remains on life support. Ultimately, the hope is that the population will grow big enough to sustain itself. 

A long term "vision" for the species aims for a Fennoscandian population of at least 2,000 individuals, a number that it says would allow the foxes to bounce back from low lemming years. Jackson, however, acknowledges that no one really knows if that number will be adequate.

Dominique Berteaux, an animal ecologist at the Université de Québec à Rimouski, studies Arctic foxes in Canada, where they're not threatened. While the strategies clearly work, he says there is no guarantee the Fennoscandian population will manage without assistance. "If feeding and culling stop, the situation might return to how it was decades ago. It's a critical limitation of the project."

Berteaux suggests some support measures might be always necessary in the area. That in turn raises more difficult questions, he says. "How long should you invest to conserve a species? At what point do you decide to stop?"

These questions are especially pertinent as climate change looms. By this century's end, continued warming could confine Arctic foxes to isolated Arctic islands, warns Ollilal: colder areas where red foxes can't reach.

Yet, says Wallén, giving up would be a mistake. "Arctic foxes have been here since the last ice age. If we stop now, they're gone forever."

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