Asian black bear
The Asian black bear, also known as the Asiatic black bear, moon bear and white-chested bear, is a medium-sized bear species native to Asia that is largely adapted to an arboreal lifestyle. It is distributed from southeastern Iran, Pakistan, India and the Himalayas to mainland Southeast Asia, the Korean Peninsula, Taiwan, mainland China and the Russian Far East to the islands of Honshū and Shikoku in Japan. It is listed as vulnerable on the IUCN Red List, and is threatened by deforestation and poaching for its body parts, which are used in traditional medicine.
Taxonomy
Ancestral and sister taxa
Biologically and morphologically, the Asian black bear represents the beginning of the arboreal specializations attained by sloth bears and sun bears. It has karyotypes nearly identical to those of the five other ursine bears, and has 74 chromosomes. It is considered the least derived of the Old World bears. It is either a surviving, albeit modified, form of Ursus etruscus, specifically the early, small variety of the Middle Villafranchian or a larger form of Ursus minimus, an extinct species that arose. With the exception of the age of the bones, it is often difficult to distinguish the remains of Ursus minimus with those of the modern Asian black bear.The Asian black bear and the American black bear are thought to have genetically diverged, though genetic evidence is inconclusive. Both the American and Asian black species are considered sister taxa and are more closely related to each other than to the other bear species. The earliest known Asian black bear specimens are known from the early Pliocene in Moldova. The earliest American black bear fossils found in Pennsylvania greatly resemble the Asian black bear. Investigations on the mitochondrial cytochrome b sequence indicate that the divergence of continental Asian and Japanese black bear populations might have occurred when bears crossed the land bridge between the Korean peninsula and Japan 500,000 years ago, which is consistent with paleontological evidence.
Subspecies
Until the Late Pleistocene, two further subspecies ranged across Europe and West Asia. These are U. t. mediterraneus from Western Europe and the Caucasus and U. t. permjak from Eastern Europe, particularly the Ural Mountains.Hybrids
Asian black bears are reproductively compatible with several other bear species, and have on occasion produced hybrid offspring. According to Jack Hanna's Monkeys on the Interstate, a bear captured in Sanford, Florida, was thought to have been the offspring of an escaped female Asian black bear and a male American black bear, and Scherren's Some notes on hybrid bears published in 1907 mentioned a successful mating between an Asian black bear and a sloth bear. In 1975, within Venezuela's "Las Delicias" Zoo, a female Asian black bear shared her enclosure with a male spectacled bear, and produced several hybrid descendants. In 2005, a possible Asian black bear–sun bear hybrid cub was captured in the Mekong River watershed of eastern Cambodia. An Asian black bear/brown bear hybrid, taken from a bile farm, is housed at the Animals Asia Foundation's China Moon Bear Rescue as of 2010.Characteristics
The Asian black bear has black fur, a light brown muzzle, and a distinct whitish or creamy patch on the chest, which is sometimes V-shaped. Its ears are bell shaped, proportionately longer than those of other bears, and stick out sideways from the head. Its tail is short, around long.Adults measure at the shoulder, and in length. Adult males weigh with an average weight of about. Adult females weigh, and large ones up to.
The Asian black bear is similar in general build to the brown bear, but is lighter and smaller. The lips and nose are larger and more mobile than those of brown bears. The skull of the Asian black bear is relatively small but massive, particularly in the lower jaw. Adult males have skulls measuring in length and in width, while female skulls are long and wide. Compared to other bears of the genus Ursus, the projections of the skull are weakly developed; the sagittal crest is low and short, even in old specimens, and does not exceed more than 19–20% of the total length of the skull, unlike in the brown bear, which has a sagittal crest comprising up to 41% of the skull's length.
Although the Asian black bear is mostly herbivorous, its jaw structure is not as specialized for plant eating as that of the giant panda; Asian black bears have much narrower zygomatic arches, and the weight ratio of the two pterygoid muscles is also much smaller in Asian black bears. The lateral slips of the temporal muscles are thicker and stronger in Asian black bears.
In contrast to the polar bear, the Asian black bear has a powerful upper body for climbing trees, and relatively weak hind legs which are shorter than those in the brown bear and American black bear. An Asian black bear with broken hind legs can still climb effectively. It is the most bipedal of all bears, and can walk upright for over. The heel pads on the forefeet are larger than those of most other bear species. Their claws, which are primarily used for climbing and digging, are slightly longer on the fore foot at than the back foot at, and are larger and more hooked than those of the American black bear. On average, adult Asian black bears are slightly smaller than American black bears, though large males can exceed the size of several other bear species.
The famed British sportsman known as the "Old Shekarry" wrote of how an Asian black bear he shot in India probably weighed no less than based on how many people it took to lift its body. The largest Asian black bear on record allegedly weighed. Zoo-kept specimens can weigh up to. Although their senses are more acute than those of brown bears, their eyesight is poor, and their hearing range is moderate, the upper limit being 30 kHz.
Distribution and habitat
During the Middle Pleistocene and early Late Pleistocene, the Asian black bear ranged from the Iberian Peninsula, the Balkans to the Ural Mountains. Today, it occurs very patchily in its former range from southeastern Iran eastward through Afghanistan and Pakistan, across the foothills of the Himalayas in India and Myanmar to mainland Southeast Asia, except Malaysia. Its range in mainland China is patchy in the northeast and south, Hainan, and it is absent in much of east-central China. Other population clusters exist in Taiwan, the southern Russian Far East and in North Korea. Small remnant populations survive in South Korea, and on Honshu and Shikoku islands.It typically inhabits deciduous forests, mixed forests and thornbrush forests. In the summer, it usually inhabits elevations of around in the Himalayas but rarely above. In winter, it descends to elevations below. In Japan, it also occurs at sea level.
There is no definitive estimate as to the number of Asian black bears: Japan posed estimates of 8–14,000 bears living on Honshū, though the reliability of this is now doubted. Although their reliability is unclear, rangewide estimates of 5–6,000 Asian black bears have been presented by Russian biologists. According to the Mammal Society of Japan, the introduction of conservation policies by the Ministry of the Environment, along with a decline in hunters due to an aging population, has led to a significant increase in the population and expansion of the range of the Japanese black bear. Estimates indicate that the population rose from approximately 15,000 individuals in 2012 to around 44,000 in 2023. Rough density estimates without corroborating methodology or data have been made in India and Pakistan, resulting in the estimates of 7–9,000 in India and 1,000 in Pakistan. Unsubstantiated estimates from China give varying estimates between 15 and 46,000, with a government estimate of 28,000.
Bangladesh
The Wildlife Trust of Bangladesh conducted an on-field survey of bears in Bangladesh from 2008 to 2010 that included Asian black bears. The survey was done in 87 different places, mostly in the north-central, northeastern and southeastern areas of Bangladesh that had historical presence of bears. The survey result says that most of the areas still has some isolated small bear populations, mainly the Asian black bears. According to the survey, the most evidence found relating to bears were of Asian black bears that included nests, footprints, local sightings, etc. There are many reports on the presence of Asian black bears in the central, north-central, northeastern and southeastern parts of Bangladesh.Although Asian black bears still occur in different parts of Bangladesh, mainly in the Chittagong Hill Tracts, the population is very small. Conservationists fear that the species will soon be extinct in the country if necessary steps to protect it are not taken in the near future.