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Masked Shrew	Range Map

The masked shrew is the smallest and most common shrew in North Dakota. It weighs an average of 1/5 of an ounce and is 3 1/2 inches overall, including body and tail. This shrew can be found statewide in a variety of moist habitats including deciduous forests, marshes, grassy bogs, or riparian areas. Masked shrews may be active at any time of the day or night. They do not hibernate and, therefore, remain active throughout the year. Often shrews burrow through snow and can sometimes be seen scurrying across the top of a snow drift.

Breeding occurs from April to October. At two years of age, the young are capable of breeding. Each female produces 2 to 3 litters per year made up of 4-10 individuals. Nests can be found in cavities of tree stumps, in fallen logs, or under rocks or other materials. They often use burrows of other mammals and occasionally make their own.

Food is something that the masked shrew requires frequently. Because of their high metabolism, they would soon die if food were not available. Favorite foods include a variety of invertebrates such as beetles, flies, ants, crickets, grasshoppers, spiders, and moths. Shrews find food by burrowing through loose soil or grass, leaves, and other material above ground.