Talpidae

(vertebrate zoology) The moles, a family of insectivoran mammals; distinguished by the forelimbs which are adapted for digging, having powerful muscles and a spadelike bony structure.

(Talpidae)

Class: Mammalia

Order: Insectivora

Family: Talpidae

Thumbnail description
Small, often long- and narrow-snouted mammals, many with large forelegs, and small or hidden eyes suited to a fossorial lifestyle

Size
Average adult total lengths (including tail) range from about 2.4–17.0 in (6–43 cm), with tail lengths of 0.6–8.3 in (1.5–21.5 cm) and weights of about 0.4–7.8 oz (12–220 g)

Number of genera, species
17 genera; 42 species

Habitat
Depending on the species, they may prefer fossorial, terrestrial, or aquatic habitats

Conservation status
Critically Endangered: 2 species; Endangered: 5 species; Vulnerable: 4 species

Distribution
North America and Eurasia

Evolution and systematics

The family Talpidae includes the moles, shrew moles, and desmans. Some taxonomists consider the desmans (Desmana and Galemys spp.) different enough from the other talpids to deserve a separate family status, but this chapter discusses them with the talpids.

The Talpidae is usually divided into three subfamilies—Uropsilinae, Desmaninae, and Talpinae—as it is here. Two other subfamilies, Scalopinae and Condylurinae, are occasionally separated out of the talpins, which is the largest subfamily.

The talpins contain 14 genera. Among that number are several genera, including Mogera, Parascaptor, and Scaptochirus, which have recently been split from the large Talpa genus.

The subfamily Uropsilinae has one genus. Taxonomists now regard its formerly lone taxon as four separate species. The subfamily Desmaninae has two monotypic genera.

Evolutionarily, the talpids are believed to have originated in Europe, and spread from there throughout Eurasia and into North America.

Physical characteristics

The typical talpid is a small, tube-shaped mammal with short, silky fur, and a narrow muzzle. The fossorial (burrowing) forms, which make up more than half the species in this family, have large, clawed hands specialized for digging, small or unseen eyes suited to their dark habitat, and fur that lies flat regardless of whether it is pointing backward or forward on the body. The aquatic and the terrestrial, surface-dwelling species lack the exaggerated forefeet, and some aquatic taxa have webbed or enlarged hind feet that propel them through the water.

Talpids also have distinctive short necks and limbs. The enlarged upper arm bone, or humerus, articulates with the collarbone, or clavicle, and the forefeet are turned outward rather than down. This combination of features permits a strong, side-ways sweeping action that is efficient for digging or swimming.

Conspecific males and females are commonly similar in appearance, although the average male is often a bit larger.

Distribution

This Northern Hemisphere family occurs in North America, Europe, and Asia. In the New World, it ranges throughout the United States, and reaches into southern Canada and northern Mexico. In the Old World, talpids live in temperate climates from the Mediterranean Sea to Japan and north well into Russia.

Some species exist over a wide area. The European mole (Talpa europaea), for example, is spread throughout Europe and into Russia. More geographically limited species include the greater Japanese shrew mole (Urotrichus talpoides), which occurs only in Japan, and the Gansu mole (Scaponulus oweni), which lives in a small area within central China.

Habitat

The talpins are chiefly fossorial, the uropsilins prefer an above-ground lifestyle, and the desmanins are semi-aquatic. The fossorial talpins exist in forests and/or fields with some opting for wet soils close to water, and a few, like the star-nosed mole (Condylura cristata), frequently leaving their tunnels for a swim. Besides the uropsilans, some species of the talpins, like the American shrew mole (Neurotrichus gibbsii) are mainly surface dwellers. These uropsilan and talpin moles that live above ground commonly shun open spaces, instead scooting beneath leaf litter or under a log, but many are known to climb into shrubs and trees. Semi-aquatic species generally favor freshwater, although a few species, such as the Russian desman (Desmana moschata), will sometimes venture into brackish water.

Behavior

As a whole, moles are best known for their tunnels, even though some talpids are not fossorial species. Evidence of tunnelers' activities is often visible as "mole runs" that zig-zag across an otherwise level lawn or forest trail. The runs are actually the roofs of the tunnels. These shallow tunnels are usually feeding runs, which the mole uses to seek out subterranean earthworms or other invertebrates. Moles can make the shallow tunnels rather quickly, with the eastern mole (Scalopus aquaticus) tunneling at a rate of up to 15 ft (4.6 m) an hour. Their activities are also frequently evident as molehills. While they pack some dirt to make the walls of the tunnel, fossorial moles typically push the leftover dirt from deep-tunnel excavations to the surface, where it forms small molehills. Molehills are usually only 6–12 in (15–30 cm) in diameter and 3–6 in (8–15 cm) tall. Deeper tunnels provide living quarters, breeding sites, and, in winter, protection from cold weather. Moles will also retreat to deeper tunnels during periods of summer drought.

Semi-aquatic species may also utilize burrows for mating or as winter shelter, but spend the bulk of their active hours in the water rather than underground. Some, like the Pyrenean desman (Galemys pyrenaicus), prefer fast-flowing streams and rivers, while others like the Russian desman, favor slow-moving streams and lakes. Surface-dwelling species are likely to find shelter under a log or leaf litter instead of a subterranean tunnel.

Active day and night, most moles are solitary animals, although some will share the same foraging grounds. In this case, they usually continue to maintain their distance from one another, often by covering the same area but at different times of the day. The Russian desman appears to be more social than other moles, and will not only share foraging tunnels but, in at least one case, its den.

Feeding ecology and diet

Talpids make good use of their Eimer's organs, which are sensory receptors on their snouts, to identify and perhaps to locate food items. The organs, which contain nerve cells, respond to touch and may also pick up seismic vibrations. The latter would help a fossorial mole, in particular, to hunt prey items in the dark tunnels. Some scientists suggest that talpid moles, including Condylura species, may also be able to feel vibrations through their forepaws. Despite these interesting adaptations possibly used in hunting, burrowing talpids seem to find most of their food by simply bumping into it while moving through their tunnels.

Swimming species, on the other hand, do appear to engage in active hunting, and are able to catch even small fish. Several fossorial, terrestrial, and semi-aquatic talpids also eat vegetative matter, but the primary diet item is invertebrates.

Predators mainly are larger mammals, including domestic cats and dogs that will unearth fossorial moles. Talpids' strong musky odor, however, often repels attackers.

Reproductive biology

In general, moles in the family Talpidae mate from late winter to late spring, with a single litter born from mid- to early summer. The schedule within a species can be moved up by a month or so among populations in warmer climates. Some moles, such as the greater Japanese shrew mole (Urotrichus talpoides), have a second litter in the summer or early fall. Gestation typically lasts four to seven weeks, with the young weaned three to four weeks after birth. Litter size averages three or four young, but can range from just one to seven or more. The young attain sexual maturity within their first year. Life span averages three to four years. Mating system varies among species.

Conservation status

Nearly a quarter of the species in this family are threatened. According to the IUCN, the list includes 10 of the approximately 42 talpid species. The Russian desman, Japanese mountain mole (Euroscaptor mizura), and Pyrenean desman are Vulnerable. The sado mole (Mogera tokudae), Echigo Plain mole (Mogera etigo), Ryukyu mole (Nesoscaptor uchidai), Yunnan shrew-mole (Uropsilus investigator), and Chinese shrew-mole (Uropsilus soricipes) are Endangered. The small-toothed mole (Euroscaptor parvidens) and Persian mole (Talpa streeti) are Critically Endangered.

Significance to humans

Burrowing moles are perhaps best known to humans for their tunnels, which are the bane of gardeners and farmers, as well as homeowners who desire a perfect lawn. Few realize that mole activities help turn over and aerate the soil, or that they feed on a considerable quantity of harmful insects, particularly beetle larvae and slugs.

Species accounts

Resources

Gorman, M. L., and R. D. Stone. The Natural History of Moles. Ithaca, NY: Comstock Publishing Associates, 1990.

Kurta, A. Mammals of the Great Lakes Region. Ann Arbor: Universtiy of Michigan Press, 1995.

Nowak, R. Walker's Mammals of the World. Baltimore: Johns Hopkins University Press, 1999.

Wilson, D., and S. Ruff, eds. The Smithsonian Book of North American Mammals. Washington, DC: Smithsonian Institution Press, 1999.

Yates, T. L., and D. W. Moore. "Speciation and Evolution in the Family Talpidae (Mammalia: Insectivora)." In Evolution of Subterranean Mammals at the Organismal and Molecular Levels. New York: Alan Liss, 1990.

Catania, K. C. "A Comparison of the Eimer's Organs of Three North American Moles: The Hairy-tailed Mole (Parascalops breweri), the Star-nosed Mole (Condylura cristata), and the Eastern Mole (Scalopus aquaticus)." Journal of Comparative Neurology 354 (1995): 150–160.

Hebert, P.D.N., ed. "Star-nosed Mole, Condylura cristata." Canada's Aquatic Environments University of Guelph,

Mason, Matthew J., and P. M. Narins. "Seismic Signal Use by Fossorial Mammals." American Zoologist 41, no. 5 (November 2001): 1171–84.

Yokohata, Y. "Biology of the Shrew Mole and Moles in Hiwa, Hiroshima Prefecture, Japan." Recent Advances in the Biology of Japanese Insectivora, Proceedings of the Symposium on the Biology of Insectivores in Japan and on the Wildlife Conservation. Hiba Society of Natural History and Hiwa Museum for Natural History. .

IUCN Species Survival Commission, Insectivore Specialist Group, Dr. Werner Haberl, Chair. Hamburgerstrasse 11, Vienna, A-1050 Austria. E-mail: shrewbib@sorex.vienna.at Web site:

IUCN 2002. 2002 IUCN Red List of Threatened Species..

Mole Tunnel.

Talpa europaea L. Mammalia, Insectivora, Talpidae. HYPP. . "Talpidae." Discover Life.

[Article by: Leslie Ann Mertz, PhD]