Meles anakumaJapanese badger

Geographic Range

Japanese badgers (Meles anakuma) are endemic to Japan, inhabiting Honshu, Kyushu, Shikoku, and Shodoshima, Japan. (Tanaka, et al., 2002; Wilson and Reeder, 2005)

Habitat

Meles anakuma is a terrestrial mammal that inhabits deciduous woods, mixed woods, copses. THis species is occasionally sighted in suburban and agricultural areas as well. Setts, or its den, are constructed in covered areas to allow it to emerge and retreat inconspicuously. Hills and slopes facilitate the removal of soil and increase drainage, making them a preferred location for sett construction. Meles anakuma can be found from sea level to 1700 m in elevation throughout its geographic range. (Neal, 1986; Tanaka, 2005; Tanaka, et al., 2002)

  • Range elevation
    0 to 1,700 m
    0.00 to ft

Physical Description

Japanese badgers are dark brown with a white face and a chocolate-brown eye stripe on their face that runs from the snout to the ear. In some specimens the stripe is reduced to a ring around the eye giving the animal a panda-like appearance. Males and females are indistinguishable by fur color. Vibrissae are present on the elongated snout and act as a tactile sense organ. Their ears are small and lie close to the side of the head. Feet are broad and have five digits with non-retractable claws. Japanese badgers are stocky with short robust limbs and a short tail. (Kaneko and Sasaki, 2008; Neal, 1986)

On average, Japanese badgers are smaller than Eurasian badgers. Skull size and sexual dimorphism is less pronounced than in Eurasian badgers. Average body weight during spring (April to July) exhibits a great deal of variation from one location to the next. In Yamaguchi, average spring body weight is 5.7±0.4 kg for males and 4.5±0.8 kg for females, whereas in Tokyo, average spring body weight is 7.7±1.3 kg in males and 5.4±0.8 kg in females in Tokyo. Yearling females weigh 3.6±0.6 kg, while yearling males weigh 4.2±0.6 kg. Total body length in adults (i.e., greater than 2 years old) is 78.7±4.9 cm in males and 72.0±2.3 cm in females. (Abramov and Puzachenko, 2005; Neal, 1986; Wilson and Reeder, 2005)

  • Sexual Dimorphism
  • male larger
  • Range mass
    3.9 to 11.0 kg
    8.59 to 24.23 lb
  • Average mass
    5.1 kg
    11.23 lb
  • Range length
    70 to 79 cm
    27.56 to 31.10 in
  • Average length
    75 cm
    29.53 in

Reproduction

Japanese badgers are polygynandrous. Males and females copulate with multiple mates throughout the year. Males signal interest to females by raising their tails into a vertical position while emitting a deep whinny purr. Prior to mating, violent interactions may occur and can include musk emission. (Neal, 1986)

Reproduction in Japanese badgers is similar to that of Eurasian badgers. Litters typically consist of 1 to 4 young, but sometimes as many as 6. Birth mass ranges from 75 to 90 g, with an average of 80 g. On average, weaning is complete by 5 weeks after birth, with most individuals weaned by 4 to 6 weeks of age. Male offspring remain with their mother for up to 26 months, whereas female offspring share a sett with the mother for only 14 months. On average, females reach sexual maturity at 24 months, while males typically reach sexual maturity at 15 months. (Neal and Cheeseman, 1996; Neal, 1986)

Unlike Eurasian badgers, Japanese badgers do not form male-female bonds for rearing cubs. During mating season, males expand their home range to overlap with those of 2 to 3 females. Male badgers are solitary most of the year, but form temporary bonds with one or several females during breeding season. Mating and fertilization can occur at any time throughout the year, but cubs are only born during spring. This is possibly due to delayed implantation, a condition in which a fertilized egg reaches the uterus but delays implantation in the uterine lining. Birthing takes place in underground dens during spring (April to June). (Neal, 1986)

  • Breeding interval
    Japanese badgers give birth once a year in spring.
  • Breeding season
    Members of this species may breed at any time of the year, but young are born in the spring.
  • Range number of offspring
    1 to 6
  • Average number of offspring
    3
  • Average gestation period
    49 days
  • Range weaning age
    4 to 6 months
  • Average time to independence
    15 months
  • Range age at sexual or reproductive maturity (female)
    1 to 3 years
  • Range age at sexual or reproductive maturity (male)
    12 to 16 weeks

On average, young Japanese badgers are weaned by 5 weeks after birth, with most individuals weaned between 4 and 6 weeks of age. Male offspring remain with their mother for up to 26 months, whereas female offspring share a sett with the mother for only 14 months. On average, females reach sexual maturity at 24 months, while males typically reach sexual maturity at 15 months. There is no information available regarding paternal care in this species. (Kaneko and Sasaki, 2008; Neal, 1986; Tanaka, et al., 2002)

  • Parental Investment
  • female parental care
  • pre-hatching/birth
    • provisioning
      • female
    • protecting
      • female
  • pre-weaning/fledging
    • provisioning
      • female
    • protecting
      • female
  • pre-independence
    • provisioning
      • female
    • protecting
      • female

Lifespan/Longevity

Little information is available concerning the lifespan of Meles anakuma. Research suggests an average lifespan of 10 years for wild individuals, but life expectancy can vary greatly depending on environment. The oldest known captive individual lived to be 19.5 years old, however, average lifespan in captivity is 13 years. (Neal, 1986)

  • Range lifespan
    Status: captivity
    19.5 (high) years
  • Average lifespan
    Status: wild
    10 years
  • Average lifespan
    Status: captivity
    13 years

Behavior

Most badgers are social and often live together in groups. However, Meles anakuma is more solitary than its close relative, Meles meles, and mating pairs of M. anakuma often live in separate setts. Currently, there is no explanation for solitary behavior in this species. (Neal, 1986; Tanaka, 2006)

Badgers are fossorial and inherit underground burrow systems called "setts". The interlocking tunnels provide shelter during the day and are also used for breeding. Setts vary in size and are expanded and refined throughout the year. Communal setts are passed on for generations, although Japanese badgers have been known to relocate. Numerous setts can be located within one home range of a particular badger. On average an adult male badger has 32 to 71 setts, while females have 20 to 41 setts. There are 4 different types of setts: main, annex, subsidiary, and outlier. Setts are classified based on the number of entrances and paths nearby. A main sett has more than 5 entrances, numerous worn paths, and large heaps of scat. Japanese badgers are territorial and often mark the outside of setts and boundaries of their territory with secretions from their subcaudal glands. (Neal, 1986; Tanaka, 2005; Tanaka, et al., 2002)

In general, Japanese badgers are nocturnal and hibernate during winter, from mid-December to February. They sleep in their setts during daytime, although during spring, breeding females are active during daylight. (Neal, 1986; Tanaka, 2006)

  • Range territory size
    1575 (high) m^2
  • Average territory size
    304 m^2

Communication and Perception

Meles anakuma eyes are unusually small for a nocturnal animal, suggesting that sight is less important than its other senses. Tapetum lucidum and a high number rod photo-receptors help M. anakuma see in the dark. Facial stripes are thought to accentuate any aggressive signals towards conspecifics. (Neal and Cheeseman, 1996)

Japanese badgers have an extremely well developed sense of smell. Secretions from the sub-caudal gland are used by to 'mark' territorial boundaries. The dominant member of each social group often scent marks each member of their group, which helps conspecifics identify dominant individuals as well as group membership. Evidence suggests urine may also be used as a scent marker. (Neal, 1986)

Food Habits

The diet of the Japanese badger consists of insects, earthworms, and fruit. They are opportunistic foragers, rather than hunters. Japanese badgers rely heavily on their sense of smell to guide them to small prey. They also consume carrion when available. (Neal and Cheeseman, 1996; Neal, 1986; Tanaka, 2005)

  • Animal Foods
  • carrion
  • insects
  • terrestrial worms
  • Plant Foods
  • fruit

Predation

Known predators of Meles anakuma include wolves, foxes, feral dogs, and humans. Similar to other mammalian species, M. anakuma uses piloerection in an attempt to deter potential predators. Its fossorial and group lifestyle may help it avoid predators. (Neal, 1986)

Ecosystem Roles

By digging burrows, Meles anakuma helps aerate soil and increase water penetration. It feeds on earthworms, berries, and insects, and may help control insect pest species as well as disperse seeds throughout its geographic range. Badgers are an important prey item for wolves, feral dogs, and humans. There is no information available concerning parasites specific to this species. (Neal, 1986; Wilson and Reeder, 2005)

Economic Importance for Humans: Positive

There are no known adverse effects of Meles anakuma on humans.

Economic Importance for Humans: Negative

Meles anakuma have been known to cause minor damage to lawns and crops while foraging for food. (Neal and Cheeseman, 1996)

  • Negative Impacts
  • crop pest

Conservation Status

Japanese badgers are a species of least concern on the IUCN's Red List of Threatened Species. Despite this, the population and distribution of Japanese badgers has been in decline over the last 30 years. Habitat loss due to development and agriculture is its biggest threat. Many badgers are killed due to road and rail traffic; tunnels and other efforts have been made in order to deter animals from crossing major roads. In addition, Northern raccoon pose a major threat to their persistence as well. Japanese badgers are considered game in Japan, but hunting has declined since the 1970s. Studies estimate there are as many as 4 adults/km² in Tokyo suburbs. (Kaneko and Sasaki, 2008; Neal, 1986)

Contributors

Julie Riney (author), University of Michigan-Ann Arbor, Phil Myers (editor), University of Michigan-Ann Arbor, John Berini (editor), Animal Diversity Web Staff.

Glossary

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.

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

carrion

flesh of dead animals.

chemical

uses smells or other chemicals to communicate

delayed implantation

in mammals, a condition in which a fertilized egg reaches the uterus but delays its implantation in the uterine lining, sometimes for several months.

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.

female parental care

parental care is carried out by females

forest

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

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

insectivore

An animal that eats mainly insects or spiders.

island endemic

animals that live only on an island or set of islands.

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

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

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

soil aeration

digs and breaks up soil so air and water can get in

solitary

lives alone

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.

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

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

2010. "ARKive images of life on earth" (On-line). ARKive images of life on earth. Accessed March 06, 2011 at http://www.arkive.org/badger/meles-meles/.

Abramov, A., A. Puzachenko. 2005. Sexual dimorphism of craniological characters in Eurasian badgers, Meles spp. (Carnivora, Mustelidae). Zoologischer Anzeiger, 244: 11-29.

Kaneko, Y., H. Sasaki. 2008. "IUCN Red List of Threatened Species" (On-line). IUCN Red List of Threatened Species. Accessed March 04, 2011 at http://www.iucnredlist.org/apps/redlist/details/136242/0.

Neal, E. 1986. The Natural History of Badgers. Great Britain: Croom Helm Ltd.

Neal, E., C. Cheeseman. 1996. Badgers. London: T & A D Poyser Ltd.

Tanaka, H. 2005. Seasonal and daily activity patterns of Japanese Badgers (Melese meles anakuma) in Western Honshu, Japan. Mammal Study, 30: 11-17.

Tanaka, H. 2006. Winter Hibernation and Body Temperature Fluctuation in the Japanese Badger, Meles meles anakuma. Zoological Science, 23: 991-997. Accessed March 04, 2011 at http://www.bioone.org/doi/full/10.2108/zsj.23.991.

Tanaka, H., A. Yamanaka, K. Endo. 2002. Spatial distribution and sett use by the Japanese Badger, Meles meles anakuma. Mammal Study, 27: 15-22. Accessed March 04, 2011 at http://www.jstage.jst.go.jp/article/mammalstudy/27/1/27_15/_article/-char/en.

Tashima, S., Y. Kaneko, T. Anezaki, M. Baba, S. Yachimori, R. Masuda. 2010. Genetic Diversity within the Japanese Badgers (Meles anakuma), as Revealed by Microsatellite Analysis. BioOne, 35-4: 221-226. Accessed March 14, 2011 at http://www.bioone.org/doi/full/10.3106/041.035.0401.

Wilson, D., D. Reeder. 2005. Mammal Species of the World: A Taxonomic and Geographic Reference. Baltimore, Maryland: The Johns Hopkins University Press.