The mighty wolverine
Bear-like, bone-crunching, carcass-stripping wolverines somehow manage to melt into Finnish forests without a trace.
From fighting large mammals to crunching bones – we get up close to the bear-like forest dwellers
“I’ve known field biologists who have worked for 20 years and never seen a wolverine.”
The sound of the wolverine struck me before I saw it. I confess I was texting at the time – a message back home to say that after 14 hours in a hide deep in the Finnish forest, all I’d seen was a small rodent, possibly a lemming, running across some logs. Then a crunch, tooth on bone. I looked up and the ‘ghost of the forest’ had arrived, just 10m in front of me, tearing at the dead pig buried just beneath the snow. I watched as it worked on the carcass, occasionally glancing up, its beady brown eyes fixing two ravens cawing from a nearby spruce, waiting for their turn to feed. After 10 minutes, with a chunk of pig clasped in its jaws, it moved off, padding silently across the snow and disappearing into the trees.
Despite my elation at seeing one of the world’s most elusive mammals at such close quarters, the pig had left a bad taste. I felt a fraud for seeing one attracted by bait, I explain to Rebecca Watters, director of the Idaho-based Wolverine Foundation, a few weeks later. “I’ve known field biologists who have worked for 20 years and never seen a wolverine in the wild,” she says, reassuringly. “If you really want to see a wolverine, and have that experience, the only way to do it is to bring one in with bait.”
Close encounter
Not that Watters had needed any lure when she saw her first wolverine. She was on a research trip in the Absaroka Mountains, on the eastern edge of Yellowstone Park, when one burst into her camp. “It ran around our campsite, looking at us and then got up on a rock to look at us from a different angle,” she says. “It was one of those really intense moments of communication with the natural world, where we were so excited and so curious about this animal, and it was excited and curious about us, too. It felt like there was this real connection. I was hooked.”
Wolverines are totally at home in the vast, often snowbound forests that run across the top of the northern hemisphere. “They are a highly snow- and cold-adapted species,” Watters explains. “They’re able to monopolise this snowy niche.” Wolverines roam huge territories that cover hundreds of square kilometres, marking the boundaries with a potent secretion from their musk glands; one of their many nicknames is ‘skunk dog’. They will only share these territories with members of the opposite sex, leading to low population densities that makes them even harder to see.
There are substantial wolverine populations in Alaska and northern Canada, despite an open season on hunting. In Europe, they are restricted to the mainland Nordic countries, with around 800 living across Sweden, Norway and Finland. In the Urals, there are thought to be at least 18,000, but as you continue eastwards across Russia, the data – based on fur trapper records – is less reliable. There are also some isolated populations in north-east China and in Mongolia.
Stocky and muscular – big males can weigh up to 30kg – and about the same height as medium-sized dogs, wolverines are solitary predators, well-suited to life in the cold north. Despite their bear-like appearance, they are one of the largest members of the mustelid family, with weasels, stoats, martens and badgers being their closest cousins.
Luxuriously dense brown coats, often with white patches on the throat and chest, protect wolverines even when temperatures plummet to –40°C, though this has also made them a prize pelt among trappers. Hefty claws mean they can climb trees and steep, snow-covered cliffs; if push comes to shove, they can swim well, too.
But what makes wolverines so well adapted to snow are their paws. Snow blankets the ground for months in these taiga forests, forming deep drifts (and thick patches remain in April when I visit). Unlike lynx and bears, which walk on their toes, wolverines are flat-footed, spreading their weight across toes and heel, as if walking on snow-shoes.
“These huge paws give wolverines an advantage over other animals when it
comes to hunting in the snow,” says John Linnell, senior research scientist at the Norwegian Institute for Nature Research. “For them, winter is a season of plenty, whereas for other animals, it’s a season of hardship.”
Wolverines are opportunistic hunters, with a keen sense of smell and an eclectic diet that includes small rodents, deer and larger animals such as the occasional moose. They’re exceptional scavengers, with a taste for carrion which in winter, as the cold takes its toll on the weak, can be plentiful.
“Wolverines seem to be in perpetual motion,” says Linnell. “They’re always criss-crossing their own ranges, zig-zagging up and down mountains. They kind of pad along – it’s not the most elegant movement but it’s incredibly efficient for gobbling up the miles. It’s all part of the hunt for carrion.” With powerful jaws and upper molars rotated 90° to face inwards, wolverines can crack the thickest of bones to get at the protein-rich marrow.
Appetite for destruction
Whereas a lynx will eat only the meat, says Linnell, “a wolverine consumes the whole thing. The skull, leg bones… everything.” It is this voraciousness that has seen the species gain an unfair reputation for greed. Its Latin name, Gulu gulu, translates as ‘glutton’, but rather than being rooted in scientific evidence it is more likely based on tall stories told by the first European explorers to set on eyes on this pugnacious forest beast. It could, they no doubt said, devour creatures many times its own size – and in one sitting.
Even the great American naturalist John James Audubon, writing in 1846, questioned the depiction of the wolverine as: “being proverbially one of the greatest gormandisers among the brutes.” Instead he suggested that these were superstitious tales passed down by generations of North American trappers.
What these pioneers were actually witnessing, argues Linnell, was caching. “If wolverines find a carcass or catch an animal, they scatter the meat across a wide area. They’ll be burying it in snow drifts, in bogs, in streams and under stones. The whole carcass can disappear incredibly quickly. Wolverines will return to caches for months on end… it tides them over if they can’t find anything fresh. They’re able to digest phenomenally hard things, and things that have been rotting in bogs for weeks. Their digestive system can pretty much take on anything.”
Another myth Watters is keen to bust is wolverines’ legendary ferocity. “Wolverines have this reputation for being total berserkers,” she says. “But pretty much 100 per cent of those first European encounters with wolverines involved trapping or hunting them.” Poke any animal with a stick, she points out, and of course it’ll be ferocious.
Not that wolverines are timid: they have been known to fight off bears and wolves. But by using baited camera-traps in forests, Watters has also seen an intelligent, even playful side to them. “Wolverines do give you the appearance of being very smart, very tricky and very adept at getting food,” she says.
The acceptance of wolverines differs from one side of the Atlantic to the other. In North American folklore, despite often being depicted as cunning tricksters, wolverines were also respected. The Innu people of Quebec revered them as the creators of the Earth, while other tribes called them doyonh, or ‘master’. A hunter that killed one – usually for its fur – would lay out an elaborate feast in front of the carcass and then cremate the body, with the wolverine’s spirit said to haunt the spot thereafter.
In Europe, however, where space to roam is more restricted, conflict is perhaps
Wolverines roam across huge territories that cover hundreds of square kilometres.
inevitable. Here wolverines are often reviled, especially when they come into contact with farmers. “Outside Lapland, Finland’s wolverines skulk in the forest, undisturbed,” says Lassi Rautiainen, who runs Wildlife Safaris Finland and started photographing the mammals in the 1990s. “But cross over into Lapland’s reindeer country and wolverines become a hated predator.” In Norway their predation of sheep is also an issue.
Last year in Finland, the 35-year ban on hunting wolverines was lifted by the government, with permits granted to cull eight individuals a year in Lapland. “For nature lovers like me, it was a strange thing and difficult to accept,” says Rautiainen. “I understand, but to accept is different.”
Seizing opportunities
Yet while a wolverine can bring down a reindeer (known as caribou in North America), more often than not it’s an opportunistic hunter, preying on stock that has become stuck in deep snow. Linnell believes that changes to farming practices also make kills more likely. Herds are bigger, he says, and many of them roam unattended. Moreover, overgrazing and a limited food supply often leave reindeer weak and vulnerable to attack, from not just wolverines but lynx and wolves too.
Counterintuitively, perhaps the wolverines’ best chance of gaining wider acceptance in Europe is to move south, reinhabiting the southern limits of their former range where there are also more people. “Nowadays, wolverines are slowly spreading out to southern Finland,” explains Anne Brax, communication director at WWF Finland. “Here they have no human enemies like there are in Lapland. Signs of wolverines have even been seen in Vantaa, around 30km from the capital Helsinki.” There are also plans to boost the genetic diversity of Finnish wolverine populations by moving 15 animals from the north to help restock central Finland.
Wolverines once patrolled the Baltic states too, says Linnell, who is not alone in looking forward to the day when they return to the forests of Estonia. But while Estonia’s large and biodiverse forests already host healthy numbers of bears, lynx and wolves and might seem the perfect location for wolverines, a lack of winter snow due to climate change means that, so far, these cold-climate specialists are only rarely sighted in their former stomping grounds.
Russia could be a different matter. Watters is excited about the kind of wolverine population that the vast Russian wilderness could potentially support.
“Wolverines have only been studied intensively for the last 20 years,” she says. “I would dearly love to start a population assessment in Russia and out towards Kamchatka… Russia is the big unknown.”