Ussuri Brown Bear Russian: Уссурийский бурый медведь Japanese: エゾヒグマ |
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Ussuri brown bear (Ursus arctos lasiotus) in the Beijing Zoo | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Carnivora |
Family: | Ursidae |
Genus: | Ursus |
Species: | U. arctos |
Subspecies: | U. arctos lasiotus |
Trinomial name | |
Ursus arctos lasiotus Gray, 1867 |
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Synonyms | |
baikalensis Ognev, 1924 |
The Ussuri brown bear (Ursus arctos lasiotus), also known as the black grizzly[1] is a subspecies of the brown bear found in the Ussuri krai, Sakhalin, the Amur Oblast, northward to the Shantar Islands, Iturup Island, northeastern China, the Korean peninsula, Hokkaidō and Kunashiri Island.[2] This subspecies is thought to be the ancestor of the North American grizzly bear. Ussuri brown bears crossed to Alaska 100,000 years ago, though they did not move south until 13,000 years ago.[3] The Ainu people worshipped the Ussuri brown bear, eating its flesh and drinking its blood as part of a religious festival known as iomante.[4]
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It is very similar to the Kamchatka brown bear, though it has a more elongated skull, a less elevated forehead, somewhat longer nasal bones and less separated zygomatic arches, and is somewhat darker in color, with some individuals being completely black, a fact which once led to the now refuted speculation that black individuals were hybrids of brown bears and Asian black bears. Adult males have skulls measuring 38.7 cm long and 23.5 cm wide. They can occasionally reach greater sizes than their Kamchatka counterparts: the largest skull measured by Sergej Ognew (1931) was only slightly smaller than that of the largest Alaskan bear on record at the time.[2]
In Sikhote Alin, Ussuri brown bears den mostly in burrows excavated into hillsides, though they will on rarer occasions den in rock outcroppings or build ground nests. These brown bears rarely encounter Asian black bears, as they den at higher elevations and on steeper slopes than the latter species. They may on rare occasions attack their smaller black cousins.[5]
In middle Sakhalin in spring, brown bears feed on the previous year's red bilberry, ants and flotsam, and at the end of the season, they concentrate on the shoots and rhizomes of tall grasses. On the southern part of the island, they feed primarily on flotsam, as well as insects and maple twigs. In springtime in Sikhote Alin, they feed on acorns, Manchurian walnuts and Korean nut pine seeds. In times of scarcity, in addition to bilberries and nuts, they capture larvae, wood-boring ants and lily roots. In early summer, they will strip bark from white-barked fir trees and feed on their cambium and sap. They will also eat berries from honeysuckle, yew, Amur grapevine and buckthorn. In southern Sakhalin, their summer diet consists of currents and chokeberries are eaten. In the August period in the middle part of the island, fish comprise 28% of their diet.[2]
In Hokkaido, the brown bear has a diet including small and large mammals, fish, birds and insects such as ants.[6]
Ussuri brown bears are occasionally preyed on by Siberian tigers, and are estimated by one source to make up 1.0-1.5% of their diet [7]; however, another source states that such attacks are rare and do not have any actual significance because Siberian tigers are almost extinct.[8] Siberian tigers most typically attack brown bears in the winter, in the hibernaculum. [9] They are typically attacked by tigers more often than the smaller black bears, due to their habit of living in more open areas and their inability to climb trees. When hunting bears, tigers will position themselves from the leeward side of a rock or fallen tree, waiting for the bear to pass by. When the bear passes, the tiger will spring from an overhead position and grab the bear from under the chin with one forepaw and the throat with the other. The immobilised bear is then killed with a bite to the spinal column. After killing a bear, the tiger will concentrate its feeding on the bear's fat deposits, such as the back, legs and groin.[10] Tiger attacks on bears tend to occur when ungulate populations decrease. While tigers can successfully hunt bears, there are also records of brown bears killing tigers (including adult male and female tigers, and tigers whose age and sex were not specified)[11], either in disputes over prey, or in self defense or for consumption.[10][12][13] There have been observations of bears that changed their path after coming across tiger trails.[10][14] Some Russian researchers have identified specific "satellite bears" who regularly "follow tigers over extensive periods of time, sequentially usurping kills" by tracking the tigers in the spring snow. [15]
About 500–1,500 Ussuri brown bears are present in Heilongjiang, and are classed as a vulnerable species. Illegal hunting and capture has become a very serious contributing factor to the decline in bear numbers, as their body parts are of high economic value.[16]
Five regional subpopulations of Ussuri brown bears are now recognized in Hokkaido. Of these, the small size and isolation of the western Ishikari subpopulation has warranted its listing as an endangered species in Japan’s Red Data Book. 90 to 152 brown bears are thought to dwell in the West Ishikari Region and from 84 to 135 in the Teshio-Mashike mountains. Their habitat has been severely limited by human activities, especially forestry practices and road construction. Excessive harvesting is also a major factor in limiting their population.[16]
In Russia, the Ussuri brown bear is considered a game animal, though it is not as extensively hunted as the Eurasian brown bear.[16]
In Hokkaido, during the first 57 years of the 20th century, 141 people died from bear attacks, and another 300 were injured.[17] The Sankebetsu brown bear incident (三毛別羆事件 Sankebetsu Higuma jiken ), which occurred in December 1915 at Sankei in the Sankebetsu district was the worst bear attack in Japanese history, and resulted in the deaths of seven people and the injuring of three others.[18] The perpetrator was a 380 kg and 2.7 m tall brown bear, which twice attacked the village of Tomamae, returning to the area the night after its first attack during the prefuneral vigil for the earlier victims. The incident is frequently referred to in modern Japanese bear incidents, and is believed to be responsible for the Japanese perception of bears as man-eaters.[17]