By Blane Klemek MINNESOTA MUSTELIDS Young

Naturalists the Slinky,Stinky Weasel family ave you ever heard anyone call somebody a weasel? If you have, then you might think Hthat being called a weasel is bad. But weasels are good hunters, and they are cunning, curious, strong, and fierce. Weasels and their relatives are mammals. They belong to the order Carnivora (meat eaters) and the family Mustelidae, also known as the weasel family or mustelids. Mustela means weasel in Latin. With 65 species, mustelids are the largest family of carnivores in the world. Eight mustelid species currently make their homes in Minnesota: short-tailed weasel, long-tailed weasel, least weasel, mink, American marten, OTTERS BY DANIEL J. COX fisher, river otter, and American badger.

 Minnesota Conservation Volunteer May–June 2003  n e MARY CLAY, DEMBINSKY t PHOTO ASSOCIATES r mammals a WEASELS flexible m Here are two TOM AND PAT LEESON specialized mustelid feet.

b One is for climb-

ou can recognize a ing and the other for hort-tailed weasels (Mustela erminea), long- The long-tailed weasel d

most mustelids g digging. Can you tell tailed weasels (M. frenata), and least weasels eats the most varied

e food of all weasels. It by their tubelike r which is which? (M. nivalis) live throughout Minnesota. In also lives in the widest Ybodies and their short theirS northern range, including Minnesota, weasels variety of habitats and legs. Some, such as badgers, hunting. Otters and minks turn white in winter. In autumn, white hairs begin climates across North are heavy and chunky. Some, are excellent swimmers that hunt to replace their brown summer coat. By winter the America. such as minks, are long and sleek. All in or near lakes, rivers, and wetlands. least weasel is mostly white, and the other two are very quick and flexible. Most female mustelids have a spe- STAN OSOLINSKI, DEMBINSKY PHOTO ASSOCIATES long-tailed weasel: summer coat When traveling, fishers, weasels, cial way to ensure their young are minks, and otters flex their spine born when food is available. Called inchworm-style, thus appearing to “delayed implantation,” this adapta- have humped backs. Because of their tion allows fertilized eggs to remain shape and flexibility, mustelids can undeveloped for many months. easily enter holes and tunnels, climb When food is plentiful, usually when trees, and swim as they hunt prey to days are warm and long, the eggs satisfy their big appetites. develop and the young are born. Mustelids must hunt much of the All mustelids have two large scent time to survive. Their long bodies do glands under the tail. These glands not store heat well, so they need lots of produce a very strong liquid scent, weight male 11 oz food to fuel their internal “furnace.” called musk, for marking territories weasel species are white except for black tips on the female 7 oz They are active in winter too: Muste- and food caches, attracting mates, tail. Owls and other predators sometimes focus on lids do not go into a deep sleep or and deterring predators. the black tip when attacking, which occasionally hibernate. They often kill more ani- causes them to miss capturing the weasel all Because weasels are mals than they can eat at one time and together. long, small, and slender cache, or store, the carcasses for later. When mustelids move across the With its long, tube-shaped body and short legs, and store little body Mustelids are adapted to hunt in dif- ice, it’s easier to see the special way the weasel can slip into just about any hole or fat, they must eat up ferent environments. Fishers and their bodies flex. to a third of their body weight each day. They martens are expert tree climbers. mink burn up to four times Badgers have strong front legs and long-tailed more energy than do long digging claws for underground BILL MARCHEL small animals that have TOM AND PAT LEESON short-tailed rounded body shapes. family of otters least

 16" burrow as it searches for food such as MINK chipmunks, pocket gophers, rabbits, moles, rats, voles, mice, shrews, and ink (Mustela vison) sometimes birds, are good swimmers snakes, frogs, insects, and spend plenty of and berries. It hunts timeM in and near water. They almost constantly. live on all kinds of land Using its keen senses of throughout Minnesota but

TOM AND PAT LEESON smell and hearing, it always near water. long-tailed weasel: winter coat checks out every nook The mink eats a wide variety and cranny. It might disappear into a hole in a log of foods. Favorite prey animals and pop out seconds later somewhere else. include fish, muskrats, rabbits, BILL MARCHEL When it is very cold, Foxes, coyotes, bobcats, domestic cats and dogs, frogs, salamanders, diving beetles, and crayfish. Wild mink are weasels hunt and live hawks, owls, martens, fishers, minks, and Mink have also been known to eat waterfowl and common throughout under the snow. They occasionally snakes hunt and eat weasels. chickens. North America, but as make thick nests of fur wetlands and wild plucked from their prey. Weasels are solitary except during the breeding Full of curiosity, mink often sit straight up to shoreland vanish, so season. Baby weasels are born blind and almost better see whatever has captured their attention. do they. Though good furless in the spring. In just three months, they are They have to look out for owls, foxes, coyotes, dogs, hunters both in water full-grown and ready to live on their own. and other predators. and on land, mink pre- In the spring a female mink gives birth to a litter fer hunting in water. easel Almost every mink has w 4 to 2 oz The least weasel is the smallest carnivore of up to 10 kits. Mother mink might make her den st t 1. a gh a white spot under its e ei in North America. It has the shortest tail under a rock pile or in an abandoned muskrat l w chin or on its throat. of all Minnesota’s weasels. house, burrow, hollow log, or tree cavity. Her kits are born blind and helpless. By autumn the JAMES PARNELL youngsters are mink weight male 2.2 lbs • female 1.6 lbs fending for short-tailed weasel or ermine themselves. weight male 4 oz female 2.6 oz TOM AND PAT LEESON

Muskrats are a The fall coat of the favorite food of short-tailed weasel most mink. Mink is between its will scavenge and summer and winter eat dead muskrats fur colors. if they are fresh. TOM AND PAT LEESON

 May–June 2003  Even though they do AMERICAN MARTEN AND FISHER not climb as well as martens, fishers spend Two to five marten as much time in trees kits are usually born as on the ground, inside a cozy tree hole always hunting. Fishers in the spring. Mother ith its foxlike face and attractive fur and martens avoid open marten lines the den coat, the American marten (Martes spaces and prefer the with mosses and grass. americana) is a beautiful animal. At safe cover of trees. But fishers do not share ter- kit Wone time martens nearly disappeared from their n ritory with martens: At te north woods home because of logging and r times they kill martens a overtrapping for their valuable fur. Today and other predators— m martens range throughout the forests of including mink, young northern Minnesota. otters, and bobcats. These exceptional tree climbers are also DANIEL J. COX fisher weight male 10.8 lbs • female 5.5 lbs called pine martens because they prefer to live in old pine forests. Martens prey mostly on small rodents such as voles and mice, but eat RIVER OTTER whatever is available. They also hunt for squirrels, DANIEL J. COX chipmunks, snowshoe hares, birds, eggs, and insects. Their large size helps The fisher (Martes pennanti) is also common river otters stay warm. throughout the north woods. Unlike martens, fish- iver otters (Lontra canadensis) have a repu- Though excellent ers live in a variety of forests. tation for goofing off. They spend a large climbers, martens also It’s not entirely clear how the fisher got its name, part of their day wrestling, sliding on their DANIEL J. COX spend time on the because fishers rarely catch fish, though they do eat Rbellies, and playing chasing games. These critters ground, where they take them. The fisher’s favorite food is the snowshoe have even been observed playing with and teasing shelter and hunt prey under fallen wood. They hare. It also eats small rodents such as mice and turtles, fish, and other animals. sometimes visit campers voles and larger prey such as raccoons, as well as Otters spend a lot of time in groups, usually of because they are nuts and berries. The fisher is one of the few preda- four to six family members. River otters are smaller attracted to some tors to successfully prey on porcupines. It repeated- than their West Coast cousins, sea otters. While sea human foods. ly attacks the porcupine’s face while avoiding its otters can weigh as much as 100 pounds, most river American or pine marten quills. When the porcupine is tired and otters weigh 15 to 30 pounds. weight male 2.2 lbs dazed, the fisher flips the animal and attacks River otters are semiaquatic (living both in water female 1.75 lbs its unprotected throat or belly. and on land) and are quite common around Min- A female fisher prefers dens inside nesota lakes and rivers. Intelligent and nosy, an trees or logs for raising her family of otter will often swim close to boaters for a better one to four young. The youngsters look. It might grunt and pop halfway out of the go off on their own before their first water to get a good look at you.

birthday. TOM AND PAT LEESON An otter easily catches fish. It floats on its back or river otter Minnesota Conservation Volunteer weight males 15 to 30 lbs Otters do not store carries its catch to shore to eat for its main meal. food, but catch as Otter fur is very dense and does a good job of WOLVERINE much as they can insulating otters underwater. Glands under the before eating. Their favorites are suckers, otter’s skin release oil to waterproof its thick fur. sunfish, bass, minnows, Because oil and water don’t mix, water rolls off the crayfish, snakes, frogs, oily fur and the otter’s skin stays dry. and sometimes musk- A river otter can hold its breath as long as two olverines (Gulo gulo) rats, ducks, and mice. minutes and dive more than 40 feet deep! have large feet and long Mother otters coax their young into the claws, and look like water to teach them to swim. Webbed feet, Wsmall bears. In fact, because of its ears and nose that close underwater, pow- strong odor and bearlike appear- erful hind legs, a long tail, and a flexible ance, American Indians once called

body help them become expert swimmers. DANIEL J. COX the wolverine “skunk bear.” favorite food: fish In North America, wolverines range throughout the forests and tundra of AMERICAN BADGER Canada and Alaska. At one time wolverines inhabited Minnesota’s How much digging wilderness, but we don’t know how must a badger do many lived there. Wolverines are hard before it catches to find because they roam very large, dinner? Studies in uilt flat, wide, and low to the ground, the remote territories ranging up to 566 Minnesota showed that American badger (Taxidea taxus) has square miles. Perhaps they were never a badger burns up incredibly loose-fitting skin with a thick more common in Minnesota than almost as much energy Blayer of fat under it. This skin helps the badger slip they are today. The last record of this digging for prey as it gets from eating it. and slide in underground tunnels. The fat layer species in Minnesota was a specimen Many other animals, grows thicker in fall to keep the badger warm taken in 1899 in Itasca County.

including foxes, owls, through the cold season. The wolverine is a good tree climber DANIEL J. COX and snakes, rely on old Not many animals can dig better or faster than a and eats just about anything, from cranberries to wolverine badger holes for shelter. weight male 32 lbs badger can. Active at night, badgers use powerful carrion. Gulo is Latin for glutton: Like other weasel female 20 lbs front legs and long claws to dig many long, deep bur- family members, the wolverine has a big appetite. It badger rows—up to 60 feet long—and to hunt for ground protects its food stores by marking the food with a weight male 18.5 lbs squirrels, gophers, and other burrowing animals. musk odor to keep away other carnivores. Wolverines are very female 14 lbs powerful for their size. Badgers live throughout Minnesota in open, Although not much bigger than a medium-size They can kill moose treeless areas where there is plenty of prey. dog, the wolverine is ferocious. Its natural enemy is and caribou, but more Two to seven baby badgers are born blind in the wolf. often they look for underground dens. When they grow up, dead ones to eat. badgers are fierce and strong. Not many Blane Klemek, Becida, is a wildlife biologist natural-

predators will attack an adult badger. JIM ROETZEL, DEMBINSKY PHOTO ASSOCIATES ist, freelance writer, and DNR private lands specialist.

 Minnesota Conservation Volunteer May–June 2003  1 234 weasel wordplay valuable furbearers 5

ACROSS 67 1 River otters are smaller than their ustelids are important furbearers, ani- cousin, the ____ mals that are hunted or trapped for fur. otter. 8 Humans have a long history of making 2 Sometimes Museful and decorative items from animal furs. mustelids _____, or American Indian chiefs adorned their war bonnets store, food for later. with weasel skins. French voyageurs and pioneers 6Wolverines look like 9101112 wore clothing made from mustelid fur. In fact, small ____. many Europeans came here to trade furs. Even 7A hunter will ____ today people trap many mustelids for fur. at a target. 8Mother mink and The highest-priced Minnesota fur today is otter. 13 14 kits live in a ___ .

COURTESY MINNESOTA HISTORICAL SOCIETY It is prized for its luster, durability, and water resis- A French-Indian 9A river otter can trapper wears furs in tance. Mink fur is favored for its combination of hold its breath for MYLES MELLOR 1870, when fur shiny, long guard hairs and dense, downy fur. Most ____ minutes. DOWN trading ruled Minnesota. mink used for today’s fashions are raised on farms. 11 Most minks have a 1Marten fur is known inside ____. Marten fur (also known as American sable) is white ___ under as American ____. 10 Single mistaken very soft and thick. Sometimes it is found in a rare their chin. 3A badger’s long ____ 11 Pose identity orange-yellow color. Fisher fur is coarser, and 13 Mustelids have two help it dig. 12 Glands under an sometimes grizzled with white hairs. large ____ glands 4A short-tailed weasel otter’s skin release skunks? The badger’s silvery long hair was popular for under their tail. is called an _____. ___ to waterproof Until recently, baggy fur coats in the 1920s. It is still used for high- 14 A female fisher may 5 Female fishers may its fur. skunks were included in build her nest inside build their nests the family Mustelidae quality paintbrushes and shaving brushes. a ____. because of their scent Wolverine fur is used to trim the hoods of parkas glands and other To learn more about mustelids, because frost doesn’t stick to the long, soft, silky hairs. weasel visit these web sites. similarities. Now some Fur trappers buy licenses and follow trapping laws, web sites scientists believe skunks which help the Department of Natural Resources Minnesota DNR. Nature might have evolved Snapshots. Learn about Minnesota’s wildlife. apart from mustelids. manage furbearer populations. V www.dnr.state.mn.us/snapshots/mammals Among differences, skunks have bigger To find online teaching materials for this article, visit Minnesota Zoo. Animals, education, and con- servation. www.mnzoo.com scent glands and www.dnr.state.mn.us/young_naturalists/weasels. stronger musk than To learn more about using Minnesota Conservation National Trappers Association. Trapping mustelids do. Some facts, furbearing mammals, and Kid’s Corner.

mammalogists place Volunteer as a teaching tool, contact Meredith ANSWERS www.nationaltrappers.com skunks into a family of McNab, [email protected] or their own, Mephitidae. 651-215-0615.

 Minnesota Conservation Volunteer May–June 2003 