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.
- Biogeographic Regions
- palearctic
- oriental
- ethiopian
- oceanic islands
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.
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.
- Habitat Regions
- temperate
- tropical
- terrestrial
- Terrestrial Biomes
- forest
- Other Habitat Features
- urban
- suburban
- agricultural
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.
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.
- Other Physical Features
- endothermic
- bilateral symmetry
- Sexual Dimorphism
- male larger
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.
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.
- Key Reproductive Features
- iteroparous
- year-round breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- induced ovulation
- fertilization
- viviparous
- sperm-storing
- delayed fertilization
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.
- Parental Investment
- no parental involvement
- altricial
-
pre-fertilization
-
protecting
- female
-
protecting
-
pre-hatching/birth
-
provisioning
- female
-
protecting
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- female
-
protecting
- male
- female
-
provisioning
-
pre-independence
-
provisioning
- female
-
protecting
- female
-
provisioning
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.
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.
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.
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.
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.
- Other Communication Modes
- scent marks
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.
Like many other shrews, this species has a high metabolic rate, and requires multiple
feeding periods.
- Primary Diet
- carnivore
- 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.
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.
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.
- 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.
- 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.
Other Comments
Asian house shrews have many other common names associated with it such as: house
shrew, Indian musk shrew, kirkanjia.
Additional Links
Contributors
Nancy Shefferly (editor), Animal Diversity Web.
Jessica Lench (author), University of Wisconsin-Stevens Point, Chris Yahnke (editor, instructor), University of Wisconsin-Stevens Point.
- Palearctic
-
living in the northern part of the Old World. In otherwords, Europe and Asia and northern Africa.
- introduced
-
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- oriental
-
found in the oriental region of the world. In other words, India and southeast Asia.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- Ethiopian
-
living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.
- introduced
-
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
- 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.
- introduced
-
referring to animal species that have been transported to and established populations in regions outside of their natural range, usually through human action.
- 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).
- tropical
-
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
- terrestrial
-
Living on the ground.
- forest
-
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
- urban
-
living in cities and large towns, landscapes dominated by human structures and activity.
- suburban
-
living in residential areas on the outskirts of large cities or towns.
- agricultural
-
living in landscapes dominated by human agriculture.
- 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).
- year-round breeding
-
breeding takes place throughout the year
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- induced ovulation
-
ovulation is stimulated by the act of copulation (does not occur spontaneously)
- fertilization
-
union of egg and spermatozoan
- viviparous
-
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
- 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.
- 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.
- 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.
- nocturnal
-
active during the night
- motile
-
having the capacity to move from one place to another.
- sedentary
-
remains in the same area
- solitary
-
lives alone
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- scent marks
-
communicates by producing scents from special gland(s) and placing them on a surface whether others can smell or taste them
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- carnivore
-
an animal that mainly eats meat
- insectivore
-
An animal that eats mainly insects or spiders.
- 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.
- 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.
References
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.
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 .