Brown Bears occupy a great variety of habitats from dry Asian steppes to Arctic shrublands to temperate rain forests. Their range overlaps that of both the American black bear Ursus americanus and Asiatic black bear U. thibetanus, and also slightly that of the Polar Bear U. maritimus. In terms of elevation, they range from sea level to 5,000 m. They occupy a greater diversity of habitats than any other species of bear and also exploit a large variety of food items, including nuts, berries, plant roots and shoots, mammals, and fish.

In Kazakhstan, Kyrgyzstan, and Tajikistan, the Tian Shan brown bear, Ursus arctos isabellinus, a subspecies of brown bear, is broadly distributed across the region. This bear inhabits lowlands and highlands from the elevation of 1000 m to 4700 m. There are almost no bears present in areas below 1000 m due to extreme anthropogenic transformation of the landscape. There are also no bears over 5000 m due to a lack of food sources. Analysis shows that the density of bears varies depending on the elevation and habitat characteristics in Kazakhstan, Kyrgyzstan, and Tajikistan. In Tajikistan, the highest density is found in the Hissar-Alay mountain system and the lowest density in the Western and Central Pamir mountains. Small populations are found on the high plateau of the Eastern Pamirs.  In Kyrgyzstan, the highest density of brown bear inhabits the Central, Inner and West Tian-Shan and a smaller number is found in other mountains of Kyrgyzstan. In Kazakhstan, this brown bear occurs in the West and North Tian-Shan but has disappeared from the Karatau range. It also inhabits the Zhongar Alatau mountains. The brown bears of Northern Kazakhstan and the Altai mountains do not belong to this subspecies.

Bears play a role in fertilizing forests by depositing scat on the forest floor. A single brown bear scat may contain tens of thousands of seeds that remain viable and can readily germinate. These seeds are then dispersed at finer spatial scales by scatter-hoarding rodents, animals that store food in several different locations in their territory. This can potentially increase seedling recruitment success and colonize a greater number of microsites. The seeds that remain in bear scat are fertilized by the fecal material, which may increase germination and seedling growth rates.

Bears also help to clean up carcasses and, as predators, they help keep populations of ungulates in balance. Finally, bears are also important as an indicator species. Bears require a variety of habitats to survive and thus managing habitat for bears benefits many other species.