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.
Animal Foods: insects; terrestrial non-insect arthropods
Plant Foods: seeds, grains, and nuts
Primary Diet: carnivore (Insectivore )
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.
Known Predators:
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.
Range mass: 23 to 147.3 g.
Range length: 100 to 150 mm.
Sexual Dimorphism: male larger
Other Physical Features: endothermic ; bilateral symmetry
Average basal metabolic rate: 0.403 W.
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.
Typical lifespan
Status: wild: 1 to 2 years.
Typical lifespan
Status: captivity: 1.5 to 2.5 years.
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
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 (Introduced , Native ); oriental (Native ); ethiopian (Introduced ); oceanic islands (Introduced )
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.
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
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
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.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
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.
Communication Channels: tactile ; acoustic ; chemical
Other Communication Modes: scent marks
Perception Channels: visual ; tactile ; acoustic ; chemical
Asian house shrews have many other common names associated with it such as: house shrew, Indian musk shrew, kirkanjia.
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.
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 gestation period: 30 days.
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.
Key Reproductive Features: iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; induced ovulation ; fertilization ; viviparous ; sperm-storing ; delayed fertilization
Average birth mass: 2.68 g.
Average gestation period: 30 days.
Average number of offspring: 3.
Average age at sexual or reproductive maturity (male)
Sex: male: 36 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 36 days.
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); pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Male, Female); pre-independence (Provisioning: Female, Protecting: Female)
The Asian house shrew (Suncus murinus) is a shrew species native to South and Southeast Asia that has been listed as Least Concern on the IUCN Red List since 2008 because of its large population and wide distribution. It has been introduced in several West Asian and East African countries.[2] It is considered an invasive species and implicated in the demise of several island lizard species.[3]
It is also called house shrew, grey musk shrew, Asian musk shrew or Indian musk shrew.[4]
Sorex murinus was the scientific name proposed by Carl Linnaeus in 1766 for a house shrew from Java.[5] In the late 18th to early 20th centuries, several house shrew zoological specimens were described as distinct species that are considered synonyms today:[1]
The house shrew has a uniform, short, dense fur of mid-grey to brownish-grey color. The tail is thick at the base and a bit narrower at the tip, and is covered with a few long, bristle-like hairs that are thinly scattered. They have short legs with five clawed toes. They have small external ears and an elongated snout. They also emit a strong odor of musk, derived from musk glands that are sometimes visible on each side of the body. The odor is especially noticeable during the breeding season.
Like all shrews, the Asian house shrew is plantigrade and long-nosed. The teeth are a series of sharp points to poke holes in insect exoskeletons. It is the largest of the shrew species, weighing between 50 and 100 g and being about 15 cm long from snout to tip of the tail.[8]
The Asian house shrew is native to South and Southeast Asia and was introduced by humans to eastern Africa, Arabia, Madagascar, the Philippines and other islands in the Indian and Pacific Oceans.[2]
The Asian house shrew is a voracious insectivore with little resistance to starvation. It is active during the night, spending the day in a burrow or hiding place in human habitations. They breed throughout the year, with each female averaging two litters per year. The gestation period is one month. One to eight young are born per litter, usually three young, in a nest made by both of the parents, wherein the young stay until they are nearly adult. It starts breeding when it is around one year old.
Studies on this shrew have suggested its suitability for use in laboratory studies of reproduction and nutrition.[9]
It is widespread and found in all habitats, including deserts and human habitations.[10]
The house shrew has a habit of moving quickly along the edges of the walls when it enters human habitations. As it runs it makes a chattering sound which resembles the sound of jingling money, which has earned them the name "money shrew" in China. When alarmed, the house shrew makes an ear-piercing, high-pitched shriek, resembling the sound of nails scraping a chalkboard or a metal fork scraping glass, which repels house cats. Predators also leave the house shrew alone because of its musky smell and even when they catch one by mistake they will rarely eat it.
Another habit of this shrew, shared with the white-toothed shrews of Europe, is that when a mother and its young travel the first will hold on to the mother's fur with its teeth, and the subsequent young will do the same with the sibling in front of it.
It is often mistaken for a rat or mouse and killed as vermin. In general it is beneficial to humans because its diet consists mostly of harmful insects such as cockroaches, and even house mice. It can therefore be considered as a biological pesticide. Unlike rats, population levels of house shrews remain low.[11] Despite its use as an insect control, it can be unpopular due to the strong odour of its droppings, which it may deposit in human dwellings behind kitchen cupboards, etc. It can also take to eating human food such as meat in kitchens, or dog or cat food. It is known to occasionally kill young chicks, making it unpopular with farmers, although rats probably kill more chicks, and more quickly. The way it is said to attack chicks, by first biting a tendon, immobilizing it and then killing and eating it, could indicate that it has a venomous bite that paralyses, as at least two other shrews species have (i.e. the Eurasian water shrew and the Northern short-tailed shrew).[12]
The Asian house shrew (Suncus murinus) is a shrew species native to South and Southeast Asia that has been listed as Least Concern on the IUCN Red List since 2008 because of its large population and wide distribution. It has been introduced in several West Asian and East African countries. It is considered an invasive species and implicated in the demise of several island lizard species.
It is also called house shrew, grey musk shrew, Asian musk shrew or Indian musk shrew.
