Caribou populations [allegedly] fall sharply | csmonitor.com

Fluctuations in caribou numbers are normal, as they are for any animal that inhabits a harsh and highly variable environment. But these declines differ from usual population expansions and contractions in one crucial aspect, says Liv Vors, lead author on the study: They’re occurring simultaneously around the world.

“[The numbers] all seem to be going down at the same time,” she says. “Usually, some would go down, and some would go up, and it would be more mixed.”

The causes of the declines differ according to habitat. In the high Arctic, the authors fault global warming.

newsminer.com • 2 Alaska caribou herds see big growth

April '09: FAIRBANKS — State wildlife biologists don’t know why the populations of two of the state’s largest caribou herds have jumped significantly in the past seven years while numbers in larger surrounding herds have declined, but nobody is complaining, especially the people who eat the caribou.

The Central Arctic Caribou Herd has more than doubled from 32,000 to 67,000 animals since 2002, becoming the state’s third-largest herd. The Teshekpuk Caribou Herd has similarly increased from 45,000 to 64,000 animals during the same time and now ranks as the state’s fourth-largest herd, based on photo censuses completed last summer.