WEASELS, BADGERS, SKUNKS, AND OTTERS: Mustelidae

PHYSICAL CHARACTERISTICS

Mustelids, members of the family Mustelidae, may either have a slim, elongated body and long tail like weasels, mink, martens, and otters, or a stocky body and short tail like badgers and wolverines. Some have webbed feet for swimming. Their fur may be uniform in color, striped, or spotted. They may be white, silver, brown, or black in color. The smallest mustelid, the least weasel, is also the smallest carnivore, weighing about 1.76 ounces (50 grams).

GEOGRAPHIC RANGE

Mustelids are found on all continents except Antarctica. They live in such countries as the United States, Canada, Mexico, Japan, Mongolia, Great Britain, Ireland, Finland, Algeria, and Morocco.

HABITAT

Mustelids inhabit a wide range of habitats. Sea otters live exclusively in the ocean, while river otters forage for food in water but den (make a den, or place to live) on land. Some live in the desert like the honey badgers, and others in tundra marshes, like ermines. Some take over their prey's dens, such as black-footed ferrets. Others, including skunks and badgers live near humans under abandoned buildings, in golf courses, and in parks.

DIET

Mustelids are either true carnivores, such as weasels, martens, and otters, feeding mainly on meat, or omnivores, like skunks, badgers, and tayras, consuming both animals and plants. Their diet consists of rodents, rabbits, reptiles, birds, insects, fruits, roots, and seeds.

BEHAVIOR AND REPRODUCTION

Mustelids are mostly nocturnal, active at night. Most are solitary, except for otters and European badgers, which form social groups. Some are excellent swimmers and skillful climbers. Musk secreted by anal glands is used to scent mark territory, as a defense mechanism in skunks, or for communication.

Only the giant otter mates with just one partner. Some species experience delayed implantation, during which the fertilized egg waits several months before attaching to the uterus to continue development. Females have a litter of one to twelve offspring, depending on the species. Males do not participate in parenting.

MUSTELIDS AND PEOPLE

Mustelids are hunted by humans for their fur. Ferrets are kept as pets, while otters are kept in zoo exhibits. Some are considered pests for spraying musk and for digging up lawns and golf courses. Others carry diseases.

DANCE OF DEATH

The weasel is known for its dance of death, actually a ploy to catch prey. The weasel stands in full view of a potential audience. It dances, spins, does somersaults, and jumps up and down. Curious onlookers, including rabbits and birds, watch transfixed. Some may draw closer for a better look. The weasel then suddenly stops dancing, rushes the closest spectator, and puts a killing bite on its neck.

CONSERVATION STATUS

The United States classifies the black-footed ferret as Endangered due to habitat loss to agriculture and the declining population of prairie dogs, its main prey. The IUCN lists the black-footed ferret as Extinct in the Wild, and four otters, two weasels, and one mink as Endangered, facing a very high risk of extinction in the wild.

ERMINE (Mustela erminea;): SPECIES ACCOUNTS

Physical characteristics: Ermines have slender bodies, useful for pursuing prey through narrow passages. They have a triangular head, rounded ears, and a long neck. Long, sensitive whiskers help track prey. The fur changes with the season and acts as a camouflage (KAM-uh-flaj), white in winter to blend in with the snow and brown with yellowish undersides and feet in summer. Their tails measure 2 to 4 inches (3 to 10 centimeters) and have black tips all year-round, which helps distract attention from the predator's body. The body is 6 to 10 inches (15 to 25 centimeters) long. Ermines weigh just 4.4 to 12.3 ounces (125 to 350 grams).

Geographic range: Ermines live in the United States and Canada, Asia (including Japan, India, Mongolia, and Siberia), Europe (including Scandinavia and Ireland), Algeria, and Greenland.

Habitat: Ermines prefer forests, grasslands, and marshy plains that provide cover and prey. They live in tree roots, hollow logs, and

burrows, holes or tunnels, inherited from their prey, usually lining their nest with fur from their prey.

Diet: Ermines are carnivorous, eating rodents, rabbits, ground squirrels, birds, and insects. They eat as much as half their body weight in food and store extra food for later use.

Behavior and reproduction: Ermines are loners, except for breeding pairs and mother-offspring groups. They use musk, an anal secretion, to mark territory and as a signal for mating. Ermines also communicate through squeaks, trills, and screeches. They are active throughout the day and night. Expert hunters, they prey on animals several times their size, killing them with a bite at the back of the neck.

Ermines mate in late spring to early summer, but the fertilized egg undergoes delayed implantation, waiting nine to ten months before attaching to the uterus to resume development. Females give birth to one or two litters of four to eight offspring the following spring and raise the young alone. Females become sexually mature, capable of reproducing, at two months of age, while males attain sexual maturity at one year. It is not unusual for adult males to mate with very young females, sometimes before they are weaned from their mother's milk. This ensures new generations even if males might not be around for mating.

Ermines and people: Some people value ermines for killing rats and mice. Americans used the black-tipped tails as ornaments, while European royalties made ceremonial robes out of the whole fur.

Conservation status: Ermines are not a threatened species. ∎

STRIPED SKUNK (Mephitis mephitis): SPECIES ACCOUNTS

Physical characteristics: Striped skunks have silky black fur. A white stripe starts on top of the head, and separates into two stripes down the sides of the back. Anal glands produce strong-smelling musk that protects against intruders. Sharp forefeet claws are designed for digging. The body is 13 to 18 inches (33 to 45 centimeters) long, and the tail measures 7 to 10 inches (18 to 25 centimeters). They weigh about 4 to 18 pounds (2 to 8 kilograms).

Geographic range: Striped skunks live in the United States, Canada, and Mexico.

Habitat: Striped skunks prefer a mixture of farmland, forest, and grassland, where they den in barns, under wood piles and in underground burrows. They adapt to desert conditions, sleeping in cool

dens during the day and foraging at night when their prey are active. They also thrive in the tundra, especially in marshes during the summer thaw. Skunks also live in suburban areas.

Diet: Striped skunks are opportunistic feeders, eating whatever food is available. Their main diet consists of small rodents and insects. They also consume reptiles, frogs, worms, birds, bird eggs, fruits, and seeds.

Behavior and reproduction: Striped skunks are active at night. They dig underground dens, use a hollowed tree stump, or share a home with rabbits and raccoons. During severe winters, they become inactive for several months, living off stored fat in their body. They do not truly hibernate, moving about when the weather warms up. Males are typically solitary but several females may den together. Mating occurs in February and March, with the males having several partners. Litters of four to ten young are born in May and are raised by the females. The young stay with the mother for up to two years.

When threatened, striped skunks give warning by stamping their front feet and growling. If the intruder does not leave, skunks raise their tails and spray a foul-smelling musk. The spray can travel up to 10 feet (3 meters), causing nausea and burning the eyes and nose.

Striped skunks and people: Skunk musk, with its odor removed, is an important perfume ingredient that enables perfume to evaporate slowly and emit fragrance longer. Striped skunks kill rodents and insects that destroy crops but they sometimes assault chickens and damage beehives. In North America, they are carriers of rabies, an often deadly disease affecting the central nervous system and transmitted through the skunk's saliva.

Conservation status: Striped skunks are not threatened. ∎

EUROPEAN OTTER (Lutra lutra): SPECIES ACCOUNTS

Physical characteristics: European otters are river otters with an elongated body and a broad, flat head. When diving, otters close the valves in their ears and nose to keep water out. The fully webbed feet work like paddles, while the flattened, muscled tail acts as a rudder for steering underwater. Sensitive whiskers help them find food, especially in muddy waters. The dark brown fur has two layers: a dense, wooly underfur and coarse, waterproof guard hairs. European otters weigh about 15 to 33 pounds (7 to 15 kilograms). Their body length is 25 to 33 inches (65 to 85 centimeters), and the tail length is 15 to 20 inches (36 to 52 centimeters).

Geographic range: European otters are found in Europe including Great Britain, France, Portugal, Spain, Ireland, Norway, Greece, Scotland, Albania, and Finland, Asia including Japan, Taiwan, Java, Sri Lanka, and Sumatra, and North Africa.

Habitat: European otters are found in freshwater habitats including rivers, streams, lakes, and ponds. They live along seashores where freshwater pools are formed from abundant rainfall. They den on land, inhabiting swamps along rivers and lakes, and on dry land among tree roots and abandoned animal burrows.

Diet: European otters consume fish, frogs, crabs, small rodents, and aquatic birds. They eat small prey in the water, but haul out larger prey to shore. They eat the equivalent of 20 percent of their body weight every day.

Behavior and reproduction: Although European otters forage for food in water, they den and breed on land, and are active at night. Otters seek freshwater for drinking and for washing sea salt from their guard hairs to keep them waterproof. They scent mark territories with anal secretions and deposit feces on logs and rocks to keep out trespassers. They are playful animals, often seen sliding down mud banks and icy slides. They communicate through chirps, chuckles, and whistles.

Breeding starts in February in water or on land. Males have two or more mating partners. The mother gives birth to two to four kits in April or June. The father leaves after the babies are born, while the young stay with the mother for about a year.

European otters and people: European otters are legally protected in some countries. Commercial fishermen consider them pests for raiding fisheries.

Conservation status: The IUCN lists the European otter as Vulnerable, facing a high risk of extinction in the wild, due to habitat destruction from dam construction, drainage of wetlands, and conversion of rivers into canals, as well as water pollution from agriculture and industries. Illegal hunting continues in many areas. Accidental trapping in fishermen's nets is also a common occurrence. ∎

EUROPEAN BADGER (Meles meles): SPECIES ACCOUNTS

Physical characteristics: European badgers have broad bodies, short legs, and short tails. They have gray backs, black undersides and legs. The white face has two parallel black stripes that start at the snout, cover the eyes, and extend to the ears. Their loose coat allows the badger to wriggle out of a predator's grasp or to quickly turn around and bite back. Long, strong front claws are designed for digging dirt and wasp nests, beehives, and insect larvae in grass roots. A see-through layer of skin protects the eyes from flying dirt and provides moisture. The back feet work like shovels for pushing out dirt. The badger weighs 22 to 44 pounds (10 to 20 kilograms), with a body length of 24 to 33 inches (60 to 85 centimeters) and a tail length of 6 to 8 inches (15 to 20 centimeters).

Geographic range: European badgers occur in all European countries and a number of Asian countries, including China, Japan, and Iran.

Habitat: European badgers prefer dense forests, but also inhabit open fields, hedgerows, and parks.

Diet: Earthworms make up about 50 percent of the European badger's diet. They also feed on small rodents, hedgehogs, snails, insects and their larvae, as well as fruits, seeds, mushrooms, and roots.

Behavior and reproduction: European badgers live together in social groups called clans, consisting of twelve to fourteen adults and their cubs. A dominant male and female rule the clan. Badgers are territorial, marking the boundaries of their home range with feces and an anal secretion called musk. They also mark one another with musk for easy identification. Badgers forage for food at night. In winter, they sleep for days but do not truly hibernate.

Badgers mate during most of the year but implantation of the fertilized egg in the uterus can be delayed by about ten months, resulting in almost all cubs being born in February or March, when food is abundant. A litter averages two to three cubs, but may have as many as five. The young stay with their mother until fall.

European badgers and people: European badgers have damaged gardens, lawns, and golf courses. Scientific experiments in Great Britain found that badger are carriers of bovine tuberculosis (bTB), and can transmit the disease to cattle. Government-sponsored killing of badgers in areas where cattle had developed bTB ended because it did not reduce cattle infection. The government continues to monitor the situation.

Conservation status: European badgers are not considered a threatened species. ∎

FOR MORE INFORMATION

Books:

Darbyshire, John, and Laurie Campbell. Badgers. Moray, U.K.: Colin Baxter Photography, 1998.

Foster-Turley, Pat, Sheila Macdonald, Chris Mason, and the IUCN/SSC Otter Specialist Group, eds. Otters: An Action Plan for their Conservation. Gland, Switzerland: IUCN, 1990.

Ivy, Bill. Weasels. Danbury, CT: Grolier Educational Corporation, 1986.

Love, John A. Sea Otters. Golden, CO: Fulcrum Publishing, 1992.

Nowak, Ronald M. "Old World Badger." Walker's Mammals of the World Online 5.1. Baltimore: Johns Hopkins University Press, 1997. http://www.press.jhu.edu/books/walkers_mammals_of_the_world/carnivora/carnivora.mustelidae.meles.html (accessed July 7, 2004).

Paine, Stefani. The World of the Sea Otter. San Francisco, CA: Sierra Club Books, 1993.

Periodicals:

Bauman, Richard. "Getting Skunked: Understanding the Antics Behind the Smell." Backpacker (May 1993): 30–31.

Conniff, Richard. "You Can Call Him 'Cute' or You Can Call Him Hungry." Smithsonian (February 1997): 81–91.

King, Carolyn M. "Mustela erminea." Mammalian Species 195 (April 8, 1983): 1–8.

Line, Les. "The Benefits of Badgers." National Wildlife (December-January 1995): 18–23.

Wade-Smith, Julia, and B. J. Verts. "Mephitis mephitis." Mammalian Species 173 (May 25, 1982): 1–7.

Weidensaul, Scott. "The Rarest of the Rare." Smithsonian (November 2000): 118–128.

Web sites:

"Black-footed ferret." U.S. Fish & Wildlife Service. http://endangered. fws.gov/i/A07.html (accessed on July 7, 2004).

National Federation of Badger Groups. http://www.badger.org.uk/tb/ (accessed on July 7, 2004).

Division of Fish, Wildlife and Marine Resources. "Furbearer Profiles: The Striped Skunk." New York State Department of Environmental Conservation. http://www.dec.state.ny.us/website/dfwmr/wildlife/wildgame/skunkinny.htm (accessed on July 7, 2004).

Badgerland Home Page. http://www.badgerland.co.uk/main.html (accessed on July 7, 2004).

"Mustelids." Arizona-Sonora Desert Museum. http://www.desertmuseum.org/books/nhsd_mustelids.html (accessed on July 7, 2004).