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Moles

Desmans, Golden Moles

Moles are small burrowing animals of the order Insectivora, mammals with teeth designed for crushing the outer shells of insects. The true moles and desmans (water-living moles) make up the family Talpidae, which inhabit most of North America and northern Eurasia. The similar golden moles of Africa, south of the Sahara, make up the family Chrysochloridae.

Moles vary from 1-3 in (24-75 mm) in length, plus a pink, naked tail that may be equally long, but is usually short. An adult male weighs more than 3.5 oz (100 g) and adult females less than that. A mole must eat its own weight in food each day or die, because its body has no fat preservation system.

Moles are thoroughly adapted for a life of digging. They have streamlined bodies, with nothing that might interfere with burrowing. Their front feet appear to come straight out of their bodies and are angled outward so that as they dig through soil, using first one hand, then the other, they appear to be swimming the breaststroke. Their flexible snouts are also used in digging, and their similarly tapered hind ends can easily move through soil. Unlike most mammals, whose hair lies toward the back of the body, a mole's fur can lie equally well in either direction as the animal moves in either direction. The fur is very soft.

Their functioning eyes reveal only light and dark. Instead they rely primarily on their senses of smell and touch. The surface of the muzzle is covered with thousands of tiny sensory organs that allow it to analyze even the most delicate touch. These organs, called Eimer's organs, identify food and digging sites. Their faces and forelimbs are also covered with special sensory hairs, called vibrissae.

The presence of moles is generally revealed by the presence of mounds of loosened soil called molehills. As they burrow, they toss the soil backward, and it eventually piles up on the surface. Surface burrows, which are visible from above, are dug in newly turned farm fields and very light soil, where the worms and other invertebrates the moles eat are near the top. Deep burrows, the digging of which produce molehills, are dug in heavier, drier soil where the invertebrates have moved downward to find moisture. These deep burrows may last many years and even many generations. They need to be rebuilt only if accidentally damaged. A mole marks a tunnel as its territory by giving off a strong odor from its scent gland. If the scent wears off and is not refreshed by the animal—perhaps because it has fallen prey to an owl—other animals may move into the burrow.

A mole's entire life centers around its burrow. Certain areas of a mole's burrow are used to store food, such as earthworms that have had their heads bitten off. In the center of the burrow is a nest lined with grasses and other dry material, such as scraps of paper hauled in from the surface. Every mole sleeps in its nest, but a female also raises her young in it until they have been weaned.

Moles breed in early spring, with two to eight little 2 inch (50 mm) young born in late spring. They are born blind, hairless, and red colored, weighing about 0.1 oz (3.5 g). They are out on their own by early fall. Though many die during their migration to find their own burrowing grounds, moles often live for six or seven years. They are capable of breeding when they are about a year old.

The nose of the strange star-nosed mole (Condylura cristata) of eastern North America is divided into 22 rubbery lobes, or tentacles, that make the black-furred animal look as if it has a pink flower on its nose. Each tentacle is covered with a large number of Eimer's organs. The star-nosed mole also has an unusual tail. Longer than most moles', it acts as a fat-storage organ during the breeding season. These are the only moles that lives in pairs, with the male helping to raise the young. Their fur is waterproof, which lets them dig into saturated soil, as well as swim in search of tiny crustaceans to eat.

The little American shrew-mole (Neurotrichus gibbsii) of the West Coast looks like a mole but has fur more like a shrew's, which doesn't change direction. This is the smallest American mole, averaging only 2.5-3 in (6-7 cm) in body length. Oddly enough, its closest relative lives straight across the Pacific in Japan. Shrew-moles, though they burrow like other moles, leave their shallow burrows to search for food among the litter on a forest floor.

The common, or eastern, American mole is Scalopus aquaticus. Despite its webbed back feet and its scientific name, the common American mole is not a water-living The European mole (Talpa europaea). Zefa/Germany/Stock Market. Reproduced by permission. animal. It has the widest range of any American mole, from Mexico to New England to Florida. Other western moles of California include the broad-footed mole (Scapanus latimanus), the coast mole (S. orarius), and Townsend's mole (S. townsendii).

There are about 13 species of Old World moles, all in genus Talpa. The European mole (T. europaea) resides in most of Europe and over into central Russia. European moles have been known to turn their molehills into mountains, or at least "fortresses," by building quite large structures above ground. Fortresses are found only in areas that flood regularly.

Moles don't eat bulbs of flowering plants as many gardeners who have watched their flowers die believe. Instead, other creatures such as meadow mice move into mole burrows, from which they can reach those succulent plant parts. Moles are now generally left alone except on golf courses. Their very soft skins were often collected at the end of the nineteenth century for use in high-quality clothing.


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