11 Intriguing Facts About Wolverines

When you think of a wolverine, the first image that comes to mind might be the tough, clawed comic book hero. This portrayal isn't far from the truth, as the real animal, a member of the weasel family, also boasts sharp claws. Once nearly driven to extinction for their fur, wolverines in the lower 48 states now face challenges from habitat loss and climate change. In November 2023, they were added to the U.S. Endangered Species List (and their populations are declining globally).

These creatures are elusive, and much about their behavior remains a mystery—but here’s what we do know.

1. Wolverines are built for cold climates.

Wolverines inhabit boreal forests and tundras across North America, Europe, and Asia, where temperatures remain cool even in summer. No wonder these animals have adapted to endure freezing conditions. With large paws that expand to twice their size upon hitting the ground, they distribute their weight to move more easily through snow (they can run at speeds of up to 30 mph). They also have thick, oily fur that resists frost—a feature that made them a prime target for fur hunters.

2. Its scientific name translates to “the glutton”—and it's a fitting title.

At up to four feet long and weighing between 22 pounds (females) and 40 pounds (males), these tough creatures are the largest members of the weasel family. While they may be smaller than some of the animals they compete with for food, a wolverine has no hesitation when facing off against wolves or bears to defend its meal.

Wolverines—or Gulo gulo, to use their scientific name—are opportunistic feeders that hunt a variety of live prey, including small creatures like hares and rodents, as well as larger, weaker or sick animals such as caribou. They'll also scavenge any carcass they can find. (They consume plants and berries too.) Frozen meat doesn’t deter them: Their upper molar is positioned sideways at 90 degrees, allowing them to tear into ice-covered remains. Their teeth are so sharp and powerful that they can even eat bones. Once they’ve found food, they often burry it to save for later; just hours after eating, they’ll go hunting again.

3. They dig.

Wolverines use their non-retractable claws for more than just burying food—they also use them to dig dens. Female wolverines can dig up to 15 feet deep into snow to build burrows for their young. These claws aren't just great for digging; they also help them climb trees (though, as shown in the video above, they’re not exactly tree-climbers).

4. Wolverines have a distinct smell.

The smell comes from specialized anal glands that emit a foul odor, which helps protect their food and marks their territory (they’ll also use it in defense, raising their tails like skunks). The scent contains traces of methylbutanoic acid (similar to stinky cheese), methyldecanoic acid, and phenylacetic acid, and resembles the smell of pine and beech martens.

5. They’re not the strongest mammal when it comes to bite force.

Folklore often claims that wolverines are the strongest animals in the wild, but science has shown that this is mostly false. While these animals can display aggression, their bite is of moderate strength: A 2007 study published in the journal Ecology found that their bite force at the canines is 224 Newtons. In comparison, the polar bear holds the record with 1646.7 Newtons, with grizzlies, tigers, and lions trailing closely behind.

The study also introduced the bite force quotient (BFQ), a way to compare the bite forces of animals with different body sizes. According to the researchers, “Species with BFQs around 100 may be regarded as having near ‘average’ bite force for their body size.” Wolverines score around 105, making their bite pretty average. Other animals such as the palm civet (161.1) and sun bear (160.5) rank higher, and several weasel species also outperform them. The highest BFQ in the paper belongs to Mustela nivalis, the least weasel, at 164. The Tasmanian devil takes the top spot with a BFQ of 181.

6. Their sense of smell is extraordinary.

Wolverines have the ability to detect prey buried as deep as 20 feet under snow and are known to locate and take down hibernating creatures.

7. Wolverines can cover vast distances.

When hunting for food, wolverines can travel up to 15 miles in just one day. In the U.S., these solitary animals typically roam an area of 47 square miles, while in Scandinavia, their territories can stretch over 270 miles. However, this distance is nothing compared to one wolverine's incredible journey in 2009: Scientists discovered that this particular animal, spotted in Colorado, had traveled more than 500 miles from its home in Wyoming.

8. They practice polyamory.

In the wild, wolverines live for about seven to 12 years. Once they reach sexual maturity around age 2, a male mates with several females who reside within his territory during the spring and summer. The fertilized eggs’ implantation is delayed until the fall or winter, with gestation lasting between four and seven weeks. Typically, females give birth to three kits, each only five inches long, weighing a few ounces, and covered in white fur. By six weeks, the kits' fur darkens, and they begin to show unique patterns on their faces, necks, and chests. The kits stay with their mother for at least a year, sometimes longer, and the father often returns to assist.

9. Wolverines are highly intelligent.

These animals cleverly use low-traffic human roads to traverse their territories and are even capable of stealing bait from traps set by scientists trying to collar them for research.

10. Other animals are often confused with wolverines.

Fishers, badgers, marmots, bear cubs, and porcupines can all appear to be wolverines when seen from a distance.

11. Researchers continue to study these elusive and mysterious creatures.

Organizations such as the Citizen Wildlife Monitoring Project have captured images of wolverines using remote cameras set up in Washington State’s wilderness areas. Meanwhile, the University of Alberta collaborates with trappers in western Canada, using GPS collars to monitor wolverines' movements.