Japanese black bear

[Gorilla king]

The Japanese black bear (Ursus thibetanus japonicus) is a subspecies of the Asian black bear that lives on three main islands of Japan: Honshu, Shikoku and Kyushu. There are said to be 10,000 black bears in Japan. The population of black bears on Shikoku and Kyushu may be endangered or extinct. There is a high price on bear parts in the black market, which threatens all bear populations in Japan. This particular species of bear are typically smaller with males only reaching 60–120 kilograms (130–260 lb) and females only weighing about 40–100 kilograms (88–220 lb). Their body length is about 120–140 centimetres (47–55 in) long.




Diet



These bears are typically herbivorous, eating mainly grasses and herbs during the spring. During the summer, they switch to berries and nuts to feed themselves for their hibernation. The bear is able to get the berries and nuts by climbing trees and using their claws to grab the food. These animals can be omnivorous and eat other wild animals and livestock when there is a need.[1] Like other bears, cannibalism occurs, as has been demonstrated when bone fragments and claws of a cub were found inside the stomach of a male black bear.

Habitat

The bears live on three Japanese islands: Honshu, Shikoku, and Kyushu. They can be found in the northeastern high snow region and the southwestern low snow region; however, they have been spotted as high as the alpine region more than 3,000 metres (9,800 feet) high. They tend to live in areas where there is an abundance of grasses and trees with berries to support their diet.[1]

Seed dispersal

Forests rely on bears as a great method for plants and trees to spread their seeds. The bears will consume the seeds and move 40% further than a distance of 500 m from the parent tree. They have the potential to spread seeds over huge areas, helping the plant life spread throughout the area. In autumn, the bears have a greater seed dispersal rate and usually the males have a larger dispersal areas than females.[2]

Conservation

There has been a huge impact on Japanese black bears' populations due to human interference. Habitat destruction is a problem for these bears as peoples' villages begin to grow. Over-hunting and poaching is also a problem. Bears' parts can be sold on the black market for a high price, which makes them very desirable. People kill a lot of these bears, reducing their numbers drastically. Because of this and the carrying capacity reduction due to habitat destruction has resulted in the recognition that the Japanese black bear is at a high risk of extinction. The species will likely be gone within the next 100 years at the rate they are currently declining.[3]


en.m.wikipedia.org/wiki/Japanese_black_bear

[Gorilla king]

Japanese black bears (Ursus thibetanus japonicus). The species is distributed throughout broadleaved deciduous forests in central Japan.





www.researchgate.net/figure/Japanese-black-bears-Ursus-thibetanus-japonicus-The-species-is-distributed-throughout_fig2_281819664

[Gorilla king]

Status of Japanese Black Bear


Abstract

This report reviews the status of Japanese black bear (Selenarctos thibetanus japonicus), and proposes a conservation plan for this species. Ten thousand black bears are estimated to live in Japan as estimated by distribution of data and density estimates of 0.11-0.18 bears/km2. Annual harvest is more than 2,000. More than 1,000 bears are killed as pests on plantations for depredations on agricultural products and other bear-human conflicts throughout the active bear season. The government does not manage black bears on the biological basis of hunting seasons, numbers, sex, or age at harvest. High commercial value of gallbladder threatens Japanese bears as in other Asian countries. Bear habitat was diminished by timber cutting for resources during the World War II period. (The rapid economic growth of Japan has been inadvertently consuming bear habitat all over the world.) For the conservation of bears, social education is necessary along with proper management of hunting and habitat on a biological basis.


www.researchgate.net/publication/261827427_Status_of_Japanese_Black_Bear

[Gorilla king]

Food Habits of Japanese Black Bear


Abstract

The food habits of Japanese black bears (Selenarctos thibetanus japonicus) were studied in the Neo Nishitani Valley, Gifu Prefecture, between 1973 and 1977. The bear live in the temperate forest zone where beech (Fagus crenata), Mongolian oak (Quercus mongolica var. grosserata), and Japanese white oak (Q. serrata) dominate. Their diet was composed mostly of plant matter throughout the year. During spring, bear ate nuts of beech and oaks which had fallen in the previous year, beech buds and shoots of herbaceous plants. During summer, bears ate a large quantity of animal matter such as ants and other insects, and much plant matter such as the fruits of Japanese cluster cherry (Prunus grayana) and dogwood (Cornus controversa). Nuts of oaks and beech were consumed in large quantities during fall. A census of the numbers of fruit trees with branches broken by bears revealed that the animals mainly used beech in 1973, Japanese white oak and Japanese chestnut (Castanea crenata) in 1974, chestnut and Mongolian oak in 1975, beech in 1976, and chestnut in 1977. In 1976, when few broken branches of beech tree were found, fallen beechnuts were eaten.


www.researchgate.net/publication/271695021_Food_Habits_of_Japanese_Black_Bear

[Gorilla king]

Movements and Habitat Use of Japanese Black Bears in Nikko


Abstract

The Japanese black bear (Selenarctos thibetanus) population has declined throughout Japan. Intensive land uses such as forestry, agriculture, and energy development have destroyed their habitat in many areas. More than 2,000 bears are harvested annually, including nuisance kills and sport hunting; however, no bear management policy has been developed or implemented. Sound ecological information is needed so we can develop such a policy. Since 1978 we have studied the ecology of Japanese black bears in Nikko, central Honshu, and reported on home range size and structure (Hazumi and Ma- ruyama, in press). In this paper we show their move- ment pattern and habitat use, especially in relation to oak (Quercus mongolica var. grosserrata) acorn crops, the most important food for these bears. STUDY AREA The 100-km2 study area is located in Nikko, To- chigi Prefecture, central Honshu. Elevations range 800-2,140 m. The climate of Outer Nikko, the eastern half of the area, is dominated by the Pacific Ocean. Summer rainfall is abundant and winter snow scarce. The climate of Inner Nikko is dominated by the Japan Sea. This area is characterized by 240 cm of annual rainfall and snow accumulations of more than 1 m are common between late November and March. The topography varies from relatively flat, gentle terrain to steep and mountainous. The subalpine zone above 1,700 m is dominated by hemlock (Tsuga div- ersifolia), fir (Abies mariesii), and birch (Betula er- manii). The montane zone below 1,700 m is dominated by conifer plantations of larch (Larix lep- tolepis), cryptomeria (Cryptomeriajaponica), and Jap- anese cedar (Chamaecyparis obtusa). Natural forests of oak, beech (Fagus crenata), and other deciduous trees occur in patches along valleys below 1,700 m.


www.researchgate.net/publication/237476501_Movements_and_Habitat_Use_of_Japanese_Black_Bears_in_Nikko

[Gorilla king]

Ecological and physiological studies of the Japanese black bear, Ursus thibetanus japonicus


Abstract

The Japanese black bear Ursus thibetanus japonicus, a large terrestrial mammal inhabits Honshu, Shikoku and Kyushu islands of Japan. However, Kyushu populations face extinction while populations on Shikoku island, in regions of Chugoku, and on the Kii peninsula are endangered. Ecological surveys such as direct observation, fecal analysis after field-sign detection and radio-tracking were carried out on Japanese black bears in Shirakawa Village, Gifu Prefecture in 1990-1994. Food habits of Japanese black bears in the spring and autumn related to the beech forest habitat of Shirakawa Village. The bears ate flower buds and seeds of the beech in the beechnut high-yield year while they ate the other food in the beechnut low-yield year. Mean home range sizes of Japanese black bears were found to be 6.4 km^2 and 3.1 km^2 in male and female bears, respectively. Studies on reproductive physiology of Japanese black bears, which were conducted under captive condition, determined that male bears exhibit remarkable seasonality in reproduction and that female bears have species-specific characteristics of reproduction including delayed implantation and parturition during hibernation. These findings suggest that an adequate feeding environment should be secured for the reproductive success and conservation of the Japanese black bear.


www.researchgate.net/publication/324955889_Ecological_and_physiological_studies_of_the_Japanese_black_bear_Ursus_thibetanus_japonicus

[Gorilla king]

Dung Beetles Attracted to Feces of Japanese Black Bear (Ursus thibetanus japonicus)


Abstract

We studied the fauna and the seasonal and diel activities of dung beetles that use the feces of the Japanese black bear (Ursus thibetanus japonicus) in Ashikawa, Yamanashi and Okutama, Tokyo. We recorded 18 species that are widely distributed and have been recorded in other mammal feces. Among these 18 species, the adults of 5 species were observed from spring to autumn, while the remaining 13 species were observed in a specific period. The proportions of the 10 species captured by bait traps confirmed that 5 species visited the feces diurnally and 4 species did so nocturnally. However, the diel visiting pattern of Onthophagus lenzii changed seasonally. We divided the 18 species into 2 functional groups: dwellers and tunnellers. Of these, 10 tunneller species were usually observed in the soil under or around feces and 8 dweller species were observed on or inside feces. The most common species, such as Onthophagus artipennis, O. ater, and Caccobius jessoensis, were tunnellers who visited the feces diurnally.


www.researchgate.net/publication/250312668_Dung_Beetles_Attracted_to_Feces_of_Japanese_Black_Bear_Ursus_thibetanus_japonicus

[Gorilla king]

Animal components in the diet of Japanese black bears Ursus thibetanus japonicus in the Kyoto area, Japan


Abstract

We measured stable carbon and nitrogen isotope ratios of hair, muscle and potential food items of Japanese black bears Ursus thibetanus japonicus in Kyoto Prefecture and its surrounding area in order to determine the contributions of animal and plant foods. The δ13C values of hair samples of bears were −22.7 ± 0.4‰ in early summer, −22.8 ± 0.3‰ in late summer and −22.7 ± 0.7‰ in autumn, while δ15N values were 3.5 ± 0.4‰ in early summer, 3.2 ± 0.4‰ in late summer and 3.6 ± 0.5‰ in autumn. The δ13C values of muscle samples of bears were −24.6‰ in early summer, −23.2‰ in late summer and −23.1 ± 0.3‰ in autumn, while δ15N values of bears captured were 3.7‰ in early summer, 5.0‰ in late summer and 4.5 ± 0.7‰ in autumn. We determined the isotopic endpoints of seven food groups from the isotope ratios of food groups and calculated the contribution of each food group using a stochastic method. Our results suggested that animal components were the major constituent of body tissue, contributing > 61% in all samples except for muscle samples collected in early summer. In muscle samples collected in early summer, none of the food items were estimated to be the major source. In cases in which the animal components were estimated to be major food sources, invertebrates were estimated to account for most of the animal components. It was concluded that animal components are an important source of tissue material in Japanese black bears in Kyoto and its surrounding area.


www.researchgate.net/publication/232684045_Animal_components_in_the_diet_of_Japanese_black_bears_Ursus_thibetanus_japonicus_in_the_Kyoto_area_Japan

[Gorilla king]

An apparent case of infanticide in the Asiatic black bear in Japan


Abstract

Despite being well-researched in several other bear species, the act of infanticide has yet to be documented in Asiatic black bears (Ursus thibetanus). We captured video footage of an apparent infanticide event in May 2016 using sensor cameras placed outside the winter den of a known female in Nagano Prefecture, Japan. We observed the presence of a known male outside the den, interacting with the female and her offspring. The female ultimately died and her body did not appear to have been consumed by the male bear. From our observations we considered both sexually selected infanticide and nutritional demand as possible motives behind the male's attack.


bioone.org/journals/ursus/volume-2021/issue-32e16/URSUS-D-20-00019.2/An-apparent-case-of-infanticide-in-the-Asiatic-black-bear/10.2192/URSUS-D-20-00019.2.short

[Gorilla king]

The average weight of the Japanese black bear ranges between 60-120 kg in the adult male and 40-100 kg in the adult female. The average body length is 110-140 cm.








books.google.com.ar/books?id=XXQ03uVmCAIC&pg=PA208&dq=Japanese+black+bear+weight&hl=en&sa=X&ved=2ahUKEwi_u86A2On4AhX_jZUCHb-6DR0Q6AF6BAgKEAM#v=onepage&q=Japanese%20black%20bear%20weight&f=false

[oldindigosilverback]

[Gorilla king]

Genetic diversity and population history of the Japanese black bear (Ursus thibetanus japonicus) based on the genome‐wide analyses


Abstract

The Japanese black bear (Ursus thibetanus japonicus) is a subspecies of the Asian black bear endemic to Mainland Japan. It has been reported that the extant Japanese bear population is genetically differentiated into several geographically restricted clusters with an estimated divergence time of 100,000–500,000 years ago. The ancestral population of the Japanese black bear migrated from the continent to the Japanese archipelago in the Pleistocene, and no interaction between continental and Japanese bear populations after their migration has been speculated. However, most of the previous studies are based only on mitochondrial DNA. Here, we sequenced the genome of a Japanese black bear and compared it with that of other Ursus individuals to evaluate the genetic status of this subspecies. We suggest that the Japanese black bear population is genetically almost uniform and has been structured only in recent 30,000 years. This inconsistency between mitochondria and nuclear DNA may be explained by the female philopatry and male‐mediated gene flow of this species. We also suggest ancestral admixture between the Japanese black bear and the Ussuri black bear (Ursus thibetanus ussuricus), implying a complex history of inter‐subspecies interactions of the Japanese black bears. Genomic evidence of ancient admixture between the Asian black bear and the American black bear (Ursus americanus) sheds new light on the population history of the Asian black bears. The genetic diversity of the Japanese black bears is remarkably lower compared to thaother bear populations, and conservation of this subspecies is an urgent issue. In this study, we sequenced the whole genome of a Japanese black bear and compared it with that of other Ursus individuals to reveal the genetic diversity and population history of the Japanese black bear. The Japanese black bear population is suggested to be genetically uniform and has been structured only in recent 30,000 years, indicating the importance of male‐mediated gene flow for maintaining the genetic diversity of this subspecies. We also suggest ancient admixtures between the Japanese black bear and other bear populations, implying complex history of inter‐species/subspecies interactions of this subspecies.


www.researchgate.net/publication/361443875_Genetic_diversity_and_population_history_of_the_Japanese_black_bear_Ursus_thibetanus_japonicus_based_on_the_genome-wide_analyses