Japan is home to several bear populations, integral to its natural ecosystems. Primarily inhabiting its extensive mountainous and forested regions, bears have coexisted with humans in the Japanese archipelago for centuries. Understanding these animals involves recognizing their distinct species and the specific environments they call home.
The Bears of Japan
Japan hosts two distinct bear species: the Asian Black Bear (Ursus thibetanus japonicus) and the Ussuri Brown Bear (Ursus arctos lasiotus). The Asian black bear typically measures 110-140 centimeters long and weighs 40-130 kilograms. They have entirely black fur, often with a distinctive white or cream crescent-shaped mark on their chest, earning them the name “moon bear.” These bears possess excellent climbing and swimming abilities, and can run 40-50 kilometers per hour.
Asian black bears are omnivores, with a diet that shifts seasonally. In spring, they primarily consume young shoots, buds, and grasses, while summer brings a focus on berries and nuts. Autumn is a critical period for fattening up before hibernation, with acorns, chestnuts, and beechnuts forming a significant part of their diet. Ussuri brown bears are substantially larger, measuring 200-230 centimeters in head-body length and weighing 150-250 kilograms, with some large males exceeding 400 kilograms. Their fur is typically dark brown, and some individuals can appear almost entirely black.
While Ussuri brown bears are also omnivorous, their diet largely consists of plant matter, including nuts, berries, and grasses. They supplement this with fish, mammals, birds, and insects. They sometimes consume cultivated crops. Both species enter hibernation, typically from December to April, during which they can be awakened by external stimuli.
Where Bears Inhabit Japan
The geographical distribution of bears in Japan is largely divided between its main islands. The Asian Black Bear is primarily found across Honshu, the largest island, and has a small, endangered population on Shikoku. They are considered likely extinct on Kyushu, with the last confirmed sighting in 1987. These bears inhabit a variety of environments, ranging from sea level up to alpine regions over 3,000 meters high, favoring broad-leaved deciduous forests rich in grasses and berry-producing trees.
Ussuri Brown Bears are exclusively found on Hokkaido, Japan’s northernmost main island. Approximately 55% of Hokkaido is inhabited by these brown bears. Their preferred habitats include extensive forests, mountainous terrain, and coastal areas, reflecting the island’s rugged and less densely populated landscape. Japan’s mountainous terrain often leads to geographically isolated bear populations, such as those in Iwate Prefecture’s Ōu and Kitakami Mountains.
Living Alongside Bears
Human-bear encounters in Japan have increased, often due to habitat encroachment and food scarcity, particularly in autumn when bears forage for winter provisions. Urban expansion and greening along roads can create corridors, drawing wildlife closer to human settlements. Bears may also expand their foraging range when natural food sources are limited.
Preventative measures are important in bear country. Making noise while hiking, carrying bear bells, and properly storing food and waste are effective deterrents. If a bear encounter occurs, remaining calm is crucial. Do not run, as bears can outpace humans; instead, slowly back away while appearing as large as possible. Should an attack occur, protect your head and neck by curling into a ball with hands over the neck. Respecting local warnings and being aware of bear activity reports are also important for safety.