Suncus murinusAsian house shrew

Geographic Range

Asian musk shrews (Suncus murinus) originated from the Indian subcontinent, ranging from southern Asia and Afghanistan to the Malay archipelago and southern Japan. This species has been introduced into northern and eastern Africa and the Middle East. Asian musk shrews are associated with forest environments, but are commonly found in household communities, and are considered commensals of humans. ("Suncus murinus", 2004)

Habitat

This species is found in forested areas, in agricultural lands, and in areas associated with human activity. There have been many studies showing that S. murinus is found in many houses and businesses. It is primarily terrestrial. ("Suncus murinus", 2004; Mushtaq-Ul-Hassan-Muhammad, et al., 1999)

Nesting occurs wherever possible. In the forest/agricultural habitat, these shrews gather leaves and any other nesting material available, then find a hidden area (snag) in which to build the nest. In a house or business this species nests in dark hidden areas, and uses any type of loose material that can be found for nest construction. (Mushtaq-Ul-Hassan-Muhammad, et al., 1999)

Physical Description

Asian musk shrews vary widely in color, size, and weight. They are mouse-like in appearance, with a long pointed nose. The fur color varies, with some individuals light gray to those which are black. Pelage is short and has a velvety texture. ("Suncus murinus", 2004; Chang-Chun-Hsiang, 1999)

The weight of an adult female ranges between 23.5 g and 82.0 g. Males are much heavier, weighing in from 33.2 g to 147.3 g. Asian musk shrews are very small in size. Total body length of adults typically varies between 100 mm and 150 mm, including the tail. The males have a large, well-developed scent gland, from which is derived the strong, musky odor, for which they received their common name. ("Suncus murinus", 2004; Chang-Chun-Hsiang, 1999)

  • Sexual Dimorphism
  • male larger
  • Range mass
    23 to 147.3 g
    0.81 to 5.19 oz
  • Range length
    100 to 150 mm
    3.94 to 5.91 in
  • Average basal metabolic rate
    0.403 W
    AnAge

Reproduction

No information was found on the mating system of Asian musk shrews. Size dimorphism between males and females suggests that they may be polygynous. However, both males and females are known to collect nesting material prior to parturition, suggesting that mating may be monogamous. Another member of the same genus, Suncus varilla, is reported to be monogamous. (Nowak, 1999)

Reproduction occurs year round, with peaks in the spring and summer. There is no behavioral estrus cycle. Development of follicles and ovulation are induced by mating. The sperm spends a long period in the female's reproductive tract before fertilization occurs. The gestation period is usually 30 days and litter size varies from 4 to 8. The young stay in the nest until they are about 75% grown. Weaning occurs between 15 and 20 days, although young can survive forced weaning as early as 12 days of age. Females reach sexual maturity around 35 days. ("Suncus murinus", 2004; Mushtaq-Ul-Hassan-M, et al., 2000; Nowak, 1999)

  • Breeding interval
    These animals can breed approximately once per month.
  • Breeding season
    This species breeds year round, although there are breeding peaks in spring and summer.
  • Range number of offspring
    4 to 8
  • Average number of offspring
    3
    AnAge
  • Average gestation period
    30 days
  • Average gestation period
    30 days
    AnAge
  • Range weaning age
    12 to 20 days
  • Range time to independence
    15 to 25 days
  • Average age at sexual or reproductive maturity (female)
    35 days
  • Average age at sexual or reproductive maturity (female)
    Sex: female
    36 days
    AnAge
  • Average age at sexual or reproductive maturity (male)
    Sex: male
    36 days
    AnAge

Both parents gather nesting material and the young do not leave the nest until seventy-five percent grown. As mammals, the female provides the offspring with milk, and probably grooms them while they are in the nest. Little is known about male parental care, beyond the gathering of nesting material. ("Suncus murinus", 2004; Nowak, 1999)

  • Parental Investment
  • no parental involvement
  • altricial
  • pre-fertilization
    • protecting
      • female
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • male
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

The lifespan of S. murinus in captivity ranges from 1.5 to 2.5 years. However, shrews generally live between one and two years of age in the wild. ("Suncus murinus", 2004; Nowak, 1999; Schmidt, 1994)

  • Typical lifespan
    Status: wild
    1 to 2 years
  • Typical lifespan
    Status: captivity
    1.5 to 2.5 years

Behavior

This is a robust and highly adaptable species. Because of this, theese shrews colonize at high densities. These shrews are nocturnal and active year round. They are typically terrestrial, and are thought to be mainly solitary. ("Suncus murinus", 2004)

Home Range

The home range size for these animals has not been reported.

Communication and Perception

Shrews apparently are solitary and intollerant of conspecifics. Their vocal sounds include a high proportion of chirps and buzzes, sounds that seem to be associated with aggressive behavior. In China S. murinus is known as the "money shrew" because of a resemblance between its rather constant, small chattering noises, and the sound of jingling coins. (Nowak, 1999)

In addition to vocal communication, these animals are likely to use some chemical cues in communicating, especially the males, which have very pronounced scent glands. ("Suncus murinus", 2004; Nowak, 1999)

Other forms of communication in these animals must be inferred from the fact that they are mammals. Tactile communication probably occurs between mates, between mothers and their young, and between individuals in aggressive encounters. Because they are mammals, these shrews have some ability to see, although shrews are not known for having well-developed eyes. So, although some visual signals may exist in this species, they are probably not as important as other forms of communication. (Nowak, 1999)

Food Habits

Suncus murinus is mainly insectivorous. Eighty-two percent of their diet constitutes insects and mammals. Asian musk shrews are also known to be opportunistic feeders. In most areas, they feed on plant material and also tend to eat a wide variety of invertebrates and human food items. They are nocturnal and feed mostly at night in forests, cultivated fields, and human populated areas. ("Suncus murinus", 2004; Prakash-Ishwar and Singh-Himmat, 1999)

Like many other shrews, this species has a high metabolic rate, and requires multiple feeding periods. ("Suncus murinus", 2004; Prakash-Ishwar and Singh-Himmat, 1999)

  • Animal Foods
  • insects
  • terrestrial non-insect arthropods
  • Plant Foods
  • seeds, grains, and nuts

Predation

Suncus murinus has few predators because of its well-developed scent gland. This gland produces a strong odor of musk that inhibits many possible predators. Among notable predators are brown tree snakes. (Pickett, 1995)

Ecosystem Roles

Suncus murinus is a dominant species in the mammal population in its natural environment. It undoubtedly affect many insect populations due to its voracious feeding behavior. (Prakash-Ishwar and Singh-Himmat, 2002)

Economic Importance for Humans: Positive

Predation on many insects is an important role in musk shrews, and probably helps to curb the population of many pest species. These shrews are also being used as a potential medical models for humans, especially in the study of periodontal disease in humans. Other research uses of S. murinus include behavioral studies in comparative psychology and related fields. ("Suncus murinus", 2004; Takata-Takashi, et al., 1999; Tsuji-Keiichiro, et al., 1999)

  • Positive Impacts
  • research and education
  • controls pest population

Economic Importance for Humans: Negative

Suncus murinus is an invasive species. They have a rapid reproductive rate, and they are not eaten by many potential predators because they are so smelly. These shrews are a growing ecological threat, preying upon or competing with many plant and animal species. Due to high densities in household areas, this species is labeled as a pest and can be very damaging to foods and other materials found in homes and businesses. ("Suncus murinus", 2004; Takata-Takashi, et al., 1999; Tsuji-Keiichiro, et al., 1999)

  • Negative Impacts
  • household pest

Conservation Status

This species is listed as an invasive species and is not protected. This species is trapped and poisoned in domestic areas. Dogs may also be used to eliminate this species in these areas. ("Suncus murinus", 2004)

Other Comments

Asian house shrews have many other common names associated with it such as: house shrew, Indian musk shrew, kirkanjia. ("Suncus murinus", 2004)

Contributors

Nancy Shefferly (editor), Animal Diversity Web.

Jessica Lench (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

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Palearctic

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

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

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

delayed fertilization

a substantial delay (longer than the minimum time required for sperm to travel to the egg) takes place between copulation and fertilization, used to describe female sperm storage.

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.

induced ovulation

ovulation is stimulated by the act of copulation (does not occur spontaneously)

insectivore

An animal that eats mainly insects or spiders.

introduced

referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

motile

having the capacity to move from one place to another.

native range

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

nocturnal

active during the night

oceanic islands

islands that are not part of continental shelf areas, they are not, and have never been, connected to a continental land mass, most typically these are volcanic islands.

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

scent marks

communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them

sedentary

remains in the same area

sexual

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

solitary

lives alone

sperm-storing

mature spermatozoa are stored by females following copulation. Male sperm storage also occurs, as sperm are retained in the male epididymes (in mammals) for a period that can, in some cases, extend over several weeks or more, but here we use the term to refer only to sperm storage by females.

suburban

living in residential areas on the outskirts of large cities or towns.

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).

terrestrial

Living on the ground.

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

urban

living in cities and large towns, landscapes dominated by human structures and activity.

visual

uses sight to communicate

viviparous

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

year-round breeding

breeding takes place throughout the year

References

2004. "Suncus murinus" (On-line). IUCN Invasive Species Specialist Group, Global Invasive Species Data Base. Accessed April 29, 2004 at http://www.issg.org/database/species/ecology.asp?si=162&fr=1&sts=tss.

Bedford, , Cooperm, Phillips , Dryden. 1994. Distinctive features of the gametes and reproductive tracts of the Asian musk shrew, Suncus murinus. Biology of Reproduction, 50: 820-834.

Chang-Chun-Hsiang, 1999. Annual reproductive patterns of male house shrews, suncus murinus, in central Taiwan. Journal of Mammology, 80: 845-854.

Mushtaq-Ul-Hassan-M, , Mahmool-Ul-Hassan-M, Beg-M-A , Khan-A-A. 2000. Reproduction and abundance of house shrew (Suncus Murinus) in villages and farmhouses of central Punjab. Pakistan Journal of Zoology, 31: 297-299.

Mushtaq-Ul-Hassan-Muhammad, , Beg-Mirza-Azhar, Khan-Akbar-Ali , Mahmood-Ul-Hassan-Muhammad. 1999. Small mammals inhibiting village households and farmhouses of Central Punjab. Pakistan Journal of Zoology, 30: 207-211.

Nowak, R. 1999. Walker's Mammals of the World, Sixth Edition. Baltimore and London: The Johns Hopkins University Press.

Pickett, B. 1995. "Order Insectivoura" (On-line ). Accessed October 18, 2002 at http://www.bobpickett.org/shrewart.htm.

Prakash-Ishwar , , Singh-Himmat. 1999. Food of a shrew, Suncus murinus inhabiting hilly tracts of south and southeastern Rajasthan. Proceedings of the National Academy of Sciences India, 69: 245-250.

Prakash-Ishwar , , Singh-Himmat. 2002. Small mammal diversity and ecology in the Aravalli mountain ecosystem in Southern Rajasthan. Proceedings of the National Academy of Sciences India, 70: 211-227.

Schmidt, R. 1994. "Shrews" (On-line ). Accessed October 18, 2002 at http://deal.unl.edu/icwdm/handbook/handbook/allPDF/mam_d87.pdf.

Takata-Takashi, , Matsuura-Masahiro, Murashima-Miwako, Miyauchi-Mutsumi , Mikai-Hiromasa. 1999. Periodontitis in the house musk shrew (Suncus Murinus): A potential animal model for human periodontal disease. Journal of Periodontology, 70: 195-200.

Tsuji-Keiichiro, , Ishii-Kiyoshi, Matsuo-Takashi , Kawano-Kazuaki. 1999. The house musk shrew Suncus murinus as a new laboratory animal for use in behavioral studies. Japanese Journal of Animal psychology, 49: 1-18.