Even as the ice-dwelling polar bear is threatened by climate change, so, too, is another bear that lives in a completely different habitat. In this case it?s the critically endangered Gobi bear (Ursus arctos gobiensis), the only bear species that has adapted to desert life. The last 22 members of this brown bear subspecies (known in Mongolian as mazaalai) live near three oases in the Gobi Desert, where the golden-colored animals subsist on a mostly vegetarian diet of hardy desert roots and other plants. But rising temperatures appear to have already started reducing the available water in the Gobi, making those plants harder to find and threatening the future of the bear.
Access to food is essential for the bears, because they must build up high levels of fat reserves for winter hibernation and gestation. According to a 2010 report (pdf) from the Gobi Bear Project, winter temperatures in that desert can fall to ?34 degrees Celsius as well as climb to 46 degrees C in summer. No other bears have adapted to living in such extreme and variable conditions. The animals dine on ?roots, berries, other vegetation, insects and occasionally rodents,? all of which can be scarce when the bears emerge from hibernation.
Food has actually been scarcer than usual for at least the past decade. Average annual rainfall in the region fell from 100 to 50 millimeters during a 14-year drought between 1993 and 2007. The Gobi Bear Project says this extended drought ?may have affected body condition and reproductive success of bears.? Supplemental feeding stations have been made available in the desert for decades and were expanded during the later years of the drought to help the bears get through the months of lean vegetation. Even though that dry spell ended a few years ago, a report last year from Eurasianet.org indicates that precipitation has again dropped to 50 millimeters per annum. The director of the Great Gobi Strictly Protected Area blames this rainfall decline on climate change.
Although the Gobi bears may never have been plentiful, their decline started in the 1960s when the Mongolian government, then dominated by the Soviet Union, encouraged an increase in livestock production in and around the desert. This policy took a toll on the already sparse vegetation and led to some poaching of bears, which were likely seen as a threat to the domesticated animals. In a sad irony scientists have found no evidence that the bears attack or eat any of the other large animals that live in the desert, such as ibex or camels.
Just a few years ago estimates put the number of Gobi Bears at as many as 50; the recent figure of 22 survivors comes from a population survey just completed by the Mongolian government and wildlife experts. Mongolia, which banned Gobi bear hunting in 1953, has now declared 2013 the ?Year of Protecting the Gobi Bear.? The Chinese media agency Xinhua reports that the Ministry of Environment and Green Development of Mongolia has also formed a working group to explore ways of boosting the bears? population, and will establish a new nature reserve to protect their habitat.
Meanwhile, scientists continue to study the shy and elusive bears whenever they can. Some have been briefly captured and fitted with GPS radio collars, which has helped to map the animals? habitat use. The Gobi Bear Project has also used hair traps at feeder sites to collect samples, allowing DNA analysis, which has revealed that the bears have low genetic diversity but shows no evidence of inbreeding-based disorders. Future efforts, including both scientific studies and supplemental feeding stations, will rely on adequate funding, some of which may come from international organizations such as Vital Ground, which established its own Gobi Bear Initiative in 2011.
Photo via the Gobi Bear Project
Source: http://rss.sciam.com/click.phdo?i=455166287bb4f4e36df9bfdde8447d34
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