BEIJING, Oct. 19 (Xinhuanet) -- The annual update of the State of the Arctic report reveals the northern polar region is under increasing stress from warming temperatures as evidenced by changing wildlife habit, local climate conditions and what one scientists calls "shrubifying."

Sea ice fell well below the previous record, caribou are declining in many areas and permafrost is melting, according to the report.

Mike Gill, of the Circumpolar Biodiversity Monitoring Program in Whitehorse, Yukon, Canada, said the biggest declines in caribou are in Canada and parts of Alaska. The herds are sensitive to changes in their range and sometimes have problems migrating in changing conditions, meaning that calving occurs before they get to new feeding grounds, resulting in higher mortality.

The tundra itself is "shrubifying," he said and the increased shrub cover over many regions affects habitat and local climate, since it tends to absorb more solar radiation. The global goose population has been on the increase, he added, resulting in overgrazing in some areas.

Scientists have expected polar regions to experience the first results of global warming and the 2006 State of the Arctic report provided a benchmark for tracking changes. Wednesday's follow-up was the first update.

Sea ice cover this year is 23 percent smaller than the past record low set in 2005 and 39 percent less than average, said Jacqueline A. Richter-Menge of the Cold Regions Research and Engineering Laboratory in Hanover, N.H.

Vladimir E. Romanovsky of the Geophysical Institute at the University of Alaska at Fairbanks, said the warming is affecting the permafrost in Siberia, Alaska and other regions.

"This similarity of very different regions shows the changes are not local, they are on at least a hemispherical scale," Romanovsky said.

(Agencies)