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As suggested by its name, this mole's most distinctive feature is a hairless nose ringed by a "star" of 22 pink, fleshy tentacles. During normal foraging activity, the tentacles are used to feel the mole's surroundings. When the mole encounters a potential prey item, it focuses the lowest, shortest tentacles on the prey. Using these supersensitive organs, identification of prey can be made in under half a second. When burrowing, the tentacles are held forward over the nostrils to prevent soil from entering the nose.
Equally distinct is a scaly, fleshy tail that is covered with concentric rings and short, coarse hairs, the base of which serves as a fat storage organ during the winter.
Like other moles, the star-nosed has a stout, roughly cylindrical body with heavily-built forelimbs, broad feet and large claws. While its eyes may only be useful for sensing light and dark, its external ear openings are much larger than those of other North American species, suggesting that it has excellent hearing. Its sense of smell is probably also fairly well-developed.
The star-nosed mole is 7-8 inches long and weighs 1-2.5 ounces.
Distribution and Habitat
The star-nosed mole is native to eastern North America, from the Atlantic Ocean west to Manitoba and North Dakota and south to Ohio and Virginia, and along the Atlantic coast south to Georgia, as well as throughout the Appalachian mountain. There are two geographic subspecies: C. cristata cristata in the north, C. c. parva in the south, with the former being larger.
Star-nosed moles are found in a variety of habitats with moist soil. It prefers areas of poor drainage, including both coniferous and deciduous forests, clearings, wet meadows, marshes and peatlands, and along the banks of streams, lakes, and ponds. Although it prefers wet areas, it has been found in dry meadows as far as 1,300 feet from water, and at altitudes of up to 5,500 feet in the Great Smoky Mountains.
This mole pushes its way through the surface layers of soil to catch invertebrates such as beetle larvae and earthworms. However, star-nosed moles living near water acquire only 12-25 percent of their food in this fashion, taking the rest underwater. Aquatic insects and annelids form the bulk of the diet with mollusks, crustacea, small amphibians and fish making up the remainder. Bottom-dwelling aquatic invertebrates are the principal winter foods of star-nosed moles living near water.
Males and females are thought to pair up as early as autumn and remain together through the mating season in March and April. Little is known about how the star-nosed mole finds or attracts a mate.
Gestation lasts approximately 45 days. Females produce one litter of offspring per year of between 2 and 7 young, with 5 being the typical litter size. At birth the young are hairless, its eyes and ears are closed, and the tentacles of the star are folded back along the rostrum. The eyes, ears, and star become functional after about 2 weeks. Young are independent at 30 days and reach maturity at 10 months.
Other Habits and Behaviors
Like other moles, the star-nosed digs and lives in a network of tunnels. The tunnels are 1-3 inches in diameter and extend from just below the surface of the ground to a depth of 24 inches. Individuals living in wet soils burrow above and below the water table, and moles near water usually have tunnels that open at, or below, the water surface. Enlarged, dry sections of the tunnels serve as sites for resting and brood-rearing nests, which the moles build by collecting dry leaves or grass. Sometimes a mole will build its nest where a tunnel passes beneath a stump or log. Each nest chamber is an oblong cavity 5-7 inches wide and 3-5 inches in height. The loose soil dug from the tunnels is pushed out onto the surface, forming "molehills."
The star-nosed mole's forelimbs are good for both digging and swimming. It swims underwater with alternate strokes of both front and hind feet, resulting in a characteristic zigzag motion. It is much more active on the surface than other moles, using runways (often made by other small mammals) through meadow or marsh vegetation.
Star-nosed moles are more social than other moles in eastern North America and are believed to form small, loose colonies of related individuals. It is not known if more than one mole will share a network of tunnels, other than paired males and females during the breeding season. In favorable habitat, the density of moles may be as great as 75 per hectare, though 25 or fewer per hectare is more common.
This page was last updated on March 13, 2017.