Tian Shan Brown Bear Emerging from Den After Hibernation

**WonderMomma** · #1 ● 05-12-2023, 06:17 PM

Tian Shan Brown Bear
Ursus arctos isabellinus

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The range of the omnivorous brown bear, Ursus arctos, has declined in North America, Europe, and Asia, and the species has been extirpated in North Africa. However, it remains widespread across three continents and is still one of the world’s most widely distributed terrestrial mammal. Globally the population remains large and is not significantly declining and may even be increasing in some areas. There are many small, isolated subpopulations that are at risk of extinction, but others, under more protection and management, are expanding. Isolated brown bear populations in Kazakhstan, Kyrgyzstan and Tajikistan are categorized as Vulnerable or Endangered by the IUCN red list.

Habitat

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.

Importance

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.

Threats (climate change)

The impact of climate change on brown bears in Kazakhstan, Kyrgyzstan, and Tajikistan has not yet been studied. The change in temperature will inevitably lead to challenging impacts on important food items that brown bears depend on. Generally, brown bears may be able to adapt to climate change. However, smaller and isolated populations could become more vulnerable, especially if they depend on food sources that are likely to be impacted by climate change (e.g, marmots in the Eastern Pamirs or highlands of Hissar-Alay Mountain system or important fruit-bearing vegetation). Climate change may also affect distribution patterns of bear population, as well as affect their biology, especially hibernation patterns with possible mismatches between periods of particular need and periods of availability of food sources. Climate change could also compound other more pressing threats, including the direct persecution by human, which is considered a key threat responsible for decline in bears in some parts of Tajikistan.

In the last decades in Kazakhstan, Kyrgyzstan, and Tajikistan, the bear population has been able to recover in many places benefiting also from abandonment of remote hamlets and resulting easier access to semi-wild orchards with fruit and nut trees. However, this has also led to conflict in some villages who depend on the same resources and thus bears are seen as competitors. Occasional encounters between humans and bears create dangerous situations for both. In some cases, bears also learned to prey on livestock and cattle, causing serious economic and social stress for local communities and livestock owners.