Sorex araneusEurasian shrew

Geographic Range

Sorex araneus is found in Europe, including Great Britain and the Pyrenees. The extent of its range to the east is Lake Baikal, except in the dry steppes and desert zone. It is not found in Iberia, or most of France.(Mitchell-Jones 1999, Stone 1995)

Habitat

Sorex araneus lives in variable habitats. These include woodlands, grassland, dunes, scree, heath, and hedgerows. It can live as far as the limits of the summer snow line.(Parker 1990)

Physical Description

Sorex araneus has a tricolored coat. The ventral side is grayish, and the dorsal side varies in color from black to reddish brown. Its flanks are nut brown. Its tail is brown on the dorsal side, and gray ventrally. It has small eyes and it ears are hidden in fur. It has red-tipped teeth.(Mitchell-Jones 1990, Stone 1995)

  • Range mass
    5 to 14 g
    0.18 to 0.49 oz
  • Range length
    48 to 80 mm
    1.89 to 3.15 in
  • Average basal metabolic rate
    0.348 W
    AnAge

Reproduction

Gestation takes place for 19-21 days. Young are born weighing between 0.5-0.6 grams. The young are weaned after 26-30 days, and reach sexual maturity at 9 or 10 months.(Parker 1990, Mitchell-Jones 1999)

  • Average number of offspring
    6
    AnAge
  • Range gestation period
    19 to 21 days
  • Range weaning age
    26 to 30 days
  • Range age at sexual or reproductive maturity (female)
    9 to 10 months
  • Range age at sexual or reproductive maturity (male)
    9 to 10 months

Lifespan/Longevity

Sorex araneus can live for about 2 years. (Mitchell-Jones 1990)

Behavior

Juveniles disperse shortly after weaning, and are especially vulnerable to predation during dispersal. Both sexes establish home ranges as juveniles, and are territorial. The home ranges vary in size from 370-630 m^(2). Breeding is delayed until the second year. Individuals are solitary and aggressive, and population densities range from 42-69 individuals per hectare. They are active during night and day. (Stone 1995)

Communication and Perception

Food Habits

It is an opportunistic feeder that preys upon many insects, woodlice, spiders, and earthworms. (Cove et al. 2000)

Predation

There are a number of predators of Sorex araneus, as listed below. (Kristofik 1999, Parker 1990)

Ecosystem Roles

Sorex araneus makes burrows below ground, and also uses the burrows of mice, voles, and moles. (Stone 1995)

Economic Importance for Humans: Positive

There may be some pest invertebrates in the diet of Sorex araneus.

  • Positive Impacts
  • controls pest population

Economic Importance for Humans: Negative

Sorex araneus eats helpful invertebrates such as earthworms and spiders.

Conservation Status

The main threat to Sorex araneus is by habitat destruction through road construction and development in Europe(Stone 1995).

The common shrew in England is protected by the Wildlife and Countryside Act (1981) and cannot trapped without a license (The Mammal Society 2001).

Contributors

Meghan Taylor (author), University of Michigan-Ann Arbor, Bret Weinstein (editor), University of Michigan-Ann Arbor.

Glossary

Palearctic

living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.

World Map

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

insectivore

An animal that eats mainly insects or spiders.

internal fertilization

fertilization takes place within the female's body

motile

having the capacity to move from one place to another.

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

tactile

uses touch to communicate

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

viviparous

reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.

References

January 1, 2001. "The Mammal Society" (On-line). Accessed November 25, 2001 at http://www.abdn.ac.uk/mammal/cshrew.htm.

Cove, R., D. Glue, S. Harris, C. Webbon. 2000. Changes in the food of British barn owls between 1974 and 1997. Mammal Review, 30(2): 107-129.

Kristofik, J. 1999. Small mammals in floodplain forests. Folia Zoologica, 48(3): 173-184.

Mitchell-Jones, A. 1999. The Atlas of European Mammals. San Diego, CA: Academic Press.

Parker, S. 1990. Grzimek's Encyclopedia of Mammals. New York, NY: McGraw Hill, Inc..