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Two small fawns entering an open meadow. Many mammals live on the Upper Souris NWR.  Beavers, mink, muskrats, raccoons, and weasels make their homes in and around the marshes. The upland and sandhill areas provide shelter for whitetail deer, moose, coyotes, badgers, red fox, porcupines, and snowshoe hares.


Beaver      The beaver is North America's largest rodent, weighing between 30 and 60 pounds and ranging from 25-30 inches in length (excluding the tail).  A beaver's tail is usually about 9-10 inches long and is used as a rudder.  Their powerful teeth can cut a 5-inch diameter tree in 3 minutes.  The tree bark is used for food and the remaining trunk and branches are used for building beaver lodges.  A family of beavers typically consists of a pair of adults with their yearlings and kits.  The life expectancy of a beaver in the wild is 10 years or more.

Common Porcupine  The porcupine is the second largest rodent of the northern Great Plains. Their average weight is 10-30 pounds and they are typically 26-31 inches long. Short, muscular tails and curved claws allow them to climb and perch in trees. Quills can be more than 3 inches long and are found on their back, sides, legs, and tail. More than 30,000 quills can be found on a single porcupine. Quills are not thrown at predators, but are easily released when contacted. Barbules within each quill expand over time and pull it deeper into embedded tissue, often causing infections. Porcupines may be found in willows, cottonwoods, aspens, and grasslands near riparian woodlands. They typically eat buds, small twigs, leaves from grasses and forbs, evergreen needles, and the inner bark of trees. Additional nutrient salts are taken from bones or antlers. Home ranges for these animals can be 25-35 acres.
Coyote  A coyote is about the size of a German Shepherd and typically weighs about 20-35 pounds.  They are very adaptable and able to live in a variety of habitats, including open grasslands, brush, badlands, woodlands, and mountainous areas.  Coyotes are most active from dusk until dawn, resting during the day.  Their diet consists mainly of cottontails, jackrabbits, rodents, birds, eggs, insects, fruits, and deer.  Many coyotes don't live beyond their fist year, but some have been known to live for 13 years or more.

Moose  In recent years, the moose has become a frequent sight for visitors at the Upper Souris NWR. The moose is a member of the deer family. An adult bull moose stands more than 6 feet tall at the shoulders and weighs more than 1400 pounds. Its long legs force the moose to kneel down to drink shallow water or to eat low-lying plants. The male moose has huge, flattened antlers with fork-like tines. Their eyesight is poor, but their sense of smell is keen. Good moose habitat is found in the wooded areas of Canada and the northern United States. However, the moose population on the Upper Souris NWR is expanding into the adjacent farmland. Moose are now surviving in areas where it was once thought uninhabitable by moose. Their favorite "dish" on the refuge is willows. Moose actually help control the spread of willows into the river meadows.
Muskrat  Muskrats are named for the musky odor of both males and females during the breeding season.  Their color ranges from reddish brown to blackish brown.  They prefer marshy areas with sedges cattails, and bulrushes.  Muskrat houses have underwater entrances and living areas above the water.  They will also live in burrows in streambanks.  Muskrats generally prefer roots, stems, leaves, and bulbs of aquatic plants but they will also eat corn, grains, mollusks, crayfish, carrion, and other muskrats.

Whitetail Deer  Whitetail deer are a common sight in most areas of the refuge. Adults stand more than 3 feet tall at the shoulder and males can weigh 200-300 pounds while females range from 90-200 pounds. Their coats change from reddish brown during the summer to grayish during the winter. Bucks typically shed antlers during February or March and grow new ones by early September. Whitetails can adapt to most habitats and eat a variety of foods, including crops, grasses, fruits, mushrooms, and acorns. Most deer feed in the early morning and early evening.



Last Updated: Mar 05, 2014
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