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What the sources say

WolverineGulo gulo

Every figure, record and mechanism on the Wolverine profile was written from a source, and this is the working table behind it: 47 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Alaska Department of Fish and Game

Wolverine. Alaska Department of Fish and Game.

The page saysOpportunistic carnivore and scavenger
The source saysWolverines are opportunistic; eating about anything they can find or kill. They are well adapted for scavenging.
The page saysmostly carrion from moose and caribou in winter
The source saysIn the winter wolverines primarily rely on carrion, remains of moose and caribou killed by wolves and hunters or animals that have died of natural causes.
The page saysvoles, squirrels, snowshoe hares and birds year round
The source saysThroughout the year, wolverines feed on small and medium-sized animals such as voles, squirrels, snowshoe hares, and birds
The page saysin the right situations, rarely a moose, Dall sheep or caribou
The source saysIn the right situations, wolverines can kill moose, Dall sheep or caribou, but these occurrences are rare
The page saysa powerful jaw and large neck muscles that let it crush and use bones and frozen flesh
The source saysThe wolverine has a powerful jaw and large neck muscles allowing it to crush and utilize bones and frozen flesh.
The page saysAn adult male wolverine generally weighs 11 to 18 kilograms (24 to 40 pounds) and a female 6 to 12 kilograms (13 to 26 pounds)
The source saysAdult males are 30-40% heavier than females and generally weigh 24-40 pounds (11-18 kg) while adult females weigh 13-26 pounds (6-12 kg)
The page saysIt is the largest land-dwelling member of the weasel family
The source saysThe wolverine, a relative of the mink and weasel, is the largest terrestrial member of the family Mustelidae
The page saysAlaska's state wildlife agency has documented movements of 40 miles in a day
The source saysMovements of 40 miles in a day have been documented.
The page saysFew wild wolverines appear to live longer than 5 to 7 years, though some survive to 12 or 13
The source saysIt appears that few wolverines live longer than 5 to 7 years in the wild. Some, however, do survive to 12 or 13 years of age.
The page saysWolverines have a fierce reputation, but Alaska's wildlife agency says it has often been exaggerated
The source saysWolverines have great endurance, strength, and foraging behavior, but its fierce reputation has often been exaggerated.
The page sayscontrary to stories, a wolverine will not attack a larger predator like a wolf or a bear, and avoids both, as an encounter with either may be fatal to the wolverine
The source saysContrary to stories they will not attack a larger predator, like a wolf or a bear, and avoid these animals as encounters may be fatal to the wolverine.
The page saysWolverines are opportunistic, eating about anything they can find or kill, from voles and squirrels to snowshoe hares and birds
The source saysWolverines are opportunistic; eating about anything they can find or kill ... wolverines feed on small and medium-sized animals such as voles, squirrels, snowshoe hares, and birds
The page saysIn winter they mainly rely on carrion: remains of moose and caribou killed by wolves and hunters, or animals that died of natural causes
The source saysIn the winter wolverines primarily rely on carrion, remains of moose and caribou killed by wolves and hunters or animals that have died of natural causes.
The page saysKilling a moose or caribou is rare
The source saysIn the right situations, wolverines can kill moose, Dall sheep or caribou, but these occurrences are rare.
The page saysAlaska's wildlife agency says a wolverine's powerful jaw and large neck muscles let it crush and use bones and frozen flesh
The source saysThe wolverine has a powerful jaw and large neck muscles allowing it to crush and utilize bones and frozen flesh.
The page saysAlaska's state wildlife agency says that in the right situations wolverines can kill moose, Dall sheep or caribou, but these occurrences are rare. They have been known to take young Dall sheep in spring, when they are most vulnerable.
The source saysIn the right situations, wolverines can kill moose, Dall sheep or caribou, but these occurrences are rare. They have been known to take the young Dall sheep in the spring when they are most vulnerable.
The page saysIn Alaska, a resident male's home range runs from 200 to 260 square miles, and a resident female's can be as large as 115 square miles. Most males leave home at about a year old and can roam over thousands of square miles in the next 1 to 2 years before settling an area of their own.
The source saysIn Alaska, resident male home range sizes are large ranging between 200-260 square miles. Resident females have home ranges as large as 115 square miles ... Most males leave their natal home range at about 1-years of age and can range over an area of thousands of square miles over the next 1-2 years before securing residency of an area.

Source
02

Animal Diversity Web, University of Michigan

Gulo gulo (wolverine). Animal Diversity Web, University of Michigan.

The page saysBoreal zone of the far north, including alpine forests and tundra at or above the timberline, in Alaska, northern Canada, Scandinavia and Russia.
The source saysWolverines are found in North America and northern Eurasia, in the boreal zone of the northern hemisphere ... Wolverines are found in Scandinavia and Russia ... In North America they are found in Alaska and northern Canada ... Wolverines are found in alpine forests, tundra, open grasslands, and boreal shrub transition zones at or above timberline
The page saysWolverines live in the boreal, or far northern, zone of the northern hemisphere, from Alaska and northern Canada to Scandinavia and Russia
The source saysWolverines are found in North America and northern Eurasia, in the boreal zone of the northern hemisphere ... Wolverines are found in Scandinavia and Russia ... In North America they are found in Alaska and northern Canada
The page saysOn hard ground, hoofed animals can outrun a wolverine
The source saysOn hard ground, ungulates can outrun wolverines.Note: ungulates explained as hoofed animals
The page saysIn snow, the wolverine is less likely to sink in
The source saysIn snow, wolverines are less likely to sink in
The page sayslarge claws and padded feet let it chase down prey in deep snow
The source saysThey have large claws with pads on the feet that allow them to chase down prey in deep snow.
The page saysIt can bring down prey five times bigger than itself, but generally only when deep snow leaves that prey stranded
The source saysThey are capable of bringing down prey that is five times bigger than themselves, but generally only under conditions that leave large ungulate prey stranded in deep snow.
The page saysWolverines also spray their food caches with scent gland secretions to discourage other animals from raiding them
The source saysWolverines also spray their food caches with scent gland secretions to discourage other animals from raiding them.
The page saysdangerLevel: Medium
The source saysNegative Impacts injures humansNote: can injure; ADFG says its fierce reputation has often been exaggerated, and it avoids larger predators
The page saystags: super-bite-force
The source saysa very powerful bite, with which they crush bone
The page saysit moves at a loping gallop
The source saysWolverines are mainly terrestrial and move with a loping gallop.
The page sayssometimes covering 10 to 15 kilometres without a rest
The source saysWolverines gallop with great endurance, sometimes moving 10 to 15 km without rest

Source
03

National Wildlife Federation, Wildlife Guide

Wolverine. National Wildlife Federation, Wildlife Guide.

The page saysgenerally 33 to 44 inches long including that tail
The source saysis generally 33 to 44 inches long (including tail)
The page sayshome ranges can vary from 100 to 600 square miles
The source saysHome ranges can vary from 100 to 600 square miles.
The page says"Skunk bear" is one of the wolverine's many nicknames
The source saysWolverines have a wide variety of nicknames ... nasty cat, and skunk bear.
The page sayslike most mustelids it has scent glands with a strong odor, used for marking territory and sexual signaling
The source saysThe wolverine, like most mustelids, has scent glands with a strong odor they use for marking territory and sexual signaling.

Source
04

U.S. Fish & Wildlife Service, FWS Focus

North American wolverine (Gulo gulo luscus). U.S. Fish & Wildlife Service, FWS Focus.

The page saysresembles a small bear with a bushy tail
The source saysIt resembles a small bear with a bushy tail.

Source
05

AnAge: The Animal Ageing and Longevity Database, Build 15

AnAge entry for Gulo gulo. AnAge: The Animal Ageing and Longevity Database, Build 15.

The page saysthe oldest captive wolverine on record reached 19.5 years
The source saysMaximum longevity 19.5 years (captivity)

Source
06

Wysocki & Tseng 2018

Wysocki & Tseng (2018). Allometry predicts trabecular bone structural properties in the carnivoran jaw joint. PLOS ONE.

The page saysjaw-joint bone was the stiffest and most crush-resistant
The source saysThe greatest elastic modulus and greatest relative maximum compressive strength are displayed by Gulo gulo (wolverine)Note: stiffest = greatest elastic modulus; most crush-resistant = greatest relative maximum compressive strength
The page says40 carnivores tested in a 2018 study
The source saysThrough 3D model construction, 3D printing, and compression tests, morphological and mechanical performance measures were determined for the temporomandibular joint trabecular bone structure of 40 species representative of the phylogenetic and ecology diversity of CarnivoraNote: 2018 is the paper's publication year (references list)
The page saysDurophagous (bone-crushing) teeth
The source saysa species that wields durophagous dentition and is known to crush the bones of much larger species
The page saysthe stiffest and most crush-resistant jaw-joint bone of 40 carnivores tested
The source saysThe greatest elastic modulus and greatest relative maximum compressive strength are displayed by Gulo gulo (wolverine)Note: stiffest = greatest elastic modulus; the 40 species are claimed with the tagline and body
The page saysA 2018 study 3D-printed models of the spongy bone inside the jaw joint of 40 carnivore species
The source saysThrough 3D model construction, 3D printing, and compression tests, morphological and mechanical performance measures were determined for the temporomandibular joint trabecular bone structure of 40 species representative of the phylogenetic and ecology diversity of CarnivoraNote: trabecular bone explained as spongy bone; temporomandibular joint = jaw joint; 2018 is the publication year
The page saysone animal per species
The source says(n = 1 individual per species)
The page sayssqueezed each model in a testing machine
The source saysTrabecular bone structural properties were measured by applying compressive load to each 3D-printed cylinder sample with a universal material tester.
The page saysThe wolverine's bone was the stiffest and had the greatest relative compressive strength
The source saysThe greatest elastic modulus and greatest relative maximum compressive strength are displayed by Gulo gulo (wolverine)Note: elastic modulus explained as stiffness
The page saysThe study calls the wolverine durophagous, meaning it has teeth for crushing hard food, and notes it is known to crush the bones of much larger species
The source saysa species that wields durophagous dentition and is known to crush the bones of much larger species

Source
07

Wood, Terwilliger & Copeland 2005

Wood, Terwilliger & Copeland (2005). Volatile Compounds from Anal Glands of the Wolverine, Gulo gulo. Journal of Chemical Ecology.

The page saysChemists who analyzed anal gland secretions from six wolverines found the mix complex and variable, from 45 to 71 compounds per animal
The source saysThe secretion composition was complex and variable for the six samples examined: 123 compounds were detected in total, with the number per animal ranging from 45 to 71 compounds.
The page sayswith only six compounds common to every sample, including two forms of methylbutanoic acid
The source saysOnly six compounds were common to all extracts: 3-methylbutanoic acid, 2-methylbutanoic acid
The page saysA 2005 study did not detect the highly odoriferous chemicals called thietanes and dithiolanes that turn up in the anal glands of some relatives, such as ferrets, mink, stoats and weasels. The wolverine's secretion was similar to those of the pine marten and the beech marten.
The source saysThe highly odoriferous thietanes and dithiolanes found in anal gland secretions of some members of the Mustelinae [ferrets, mink, stoats, and weasels (Mustela spp.) and zorillas (Ictonyx spp.)] were not observed. The composition of the wolverine's anal gland secretion is similar to that of two other members of the Mustelinae, the pine and beech marten (Martes spp.).Note: 2005 is the paper's publication year

Source
08

Andrén 2025

Andrén (2025). Gulo gulo. The IUCN Red List of Threatened Species 2025: e.T9561A216872666.

The page saysLeast Concern
The source saysIUCN Red List category: Least Concern (LC).

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.