Asian black bear
Asiatic black bears are diurnal, though they become nocturnal near human habitations. They may live in family groups consisting of two adults and two successive litters of young. They will walk in a procession of largest to smallest. They are good climbers of rocks and trees, and will climb to feed, rest, sun, elude enemies and hibernate. Some older bears may become too heavy to climb. Half of their life is spent in trees and they are one of the largest arboreal mammals. In the Ussuri territory in the Russian Far East, black bears can spend up to 15% of their time in trees. Asiatic black bears break branches and twigs to place under themselves when feeding on trees, thus causing many trees in their home ranges to have nest-like structures on their tops. Asiatic black bears will rest for short periods in nests on trees standing fifteen feet or higher. Asiatic black bears do not hibernate over most of their range. They may hibernate in their colder, northern ranges, though some bears will simply move to lower elevations. Nearly all pregnant sows hibernate. Black bears prepare their dens for hibernation in mid-October, and will sleep from November until March. Their dens can either be dug out hollow trees (sixty feet above ground), caves or holes in the ground, hollow logs, or steep, mountainous and sunny slopes. They may also den in abandoned brown bear dens. Asiatic black bears tend to den at lower elevations and on less steep slopes than brown bears. Female black bears emerge from dens later than do males, and female black bears with cubs emerge later than barren females. Asiatic black bears tend to be less mobile than brown bears. With sufficient food, Asian black bears can remain in an area of roughly 1–2 sq km, and sometimes even as little as 0.5–1 sq km.
Asian black bear
Asiatic black bears are omnivorous, and will feed on insects, beetle larvae, invertebrates, termites, grubs, carrion, bees, eggs, garbage, mushrooms, grasses, fruits, nuts, seeds, honey, herbs, acorns, cherries, dogwood, and grain. Although herbivorous to a greater degree than brown bears, and more carnivorous than American black bears, Asiatic black bears are not as specialized in their diet as pandas are: while pandas depend on a constant supply of low calorie, yet abundant foodstuffs, black bears are more opportunistic and have opted for a nutritional boom-or-bust economy. They thus gorge themselves on a variety of seasonal high calorie foods, storing the excess calories as fat, and then hibernate during times of scarcity. Black bears will eat pine nuts and acorns of the previous year in the April–May period. In times of scarcity, they enter river valleys to gain access to hazelnuts and insect larvae in rotting logs. From mid-May through late June, they will supplement their diet with green vegetation and fruit. Through July to September, they will climb trees to eat bird cherries, pine cones, vines and grapes. On rare occasions they will eat dead fish during the spawning season, though this constitutes a much lesser portion of their diet than in brown bears. In the 1970s, black bears were reported to kill and eat Hanuman langurs in Nepal. They appear to be more carnivorous than most other bears, including American black bears, and will kill ungulates with some regularity, including domestic livestock. Wild ungulate prey can include muntjacs, serow, takin, wild boar and adult water buffaloes, which they kill by breaking their necks.