Arctic Caribou Herds In Sustained Long-Term Decline - Vancouver Sun

[hatrack]

EDIT

In the weeks that followed, Miller saw plenty of the succulent saxifrage flowers that Peary caribou feed on, but precious few animals and not a single calf at that time of year. What he did discover with alarming regularity were the carcasses of caribou and muskoxen strewn across the tundra. By the time Miller completed his study that summer, he had counted just 300 live animals, a small fraction of what he had expected to see. When the die-off finally ended two years later, almost 98 per cent of the caribou that were on the south-central Queen Elizabeth Islands three years earlier were gone.

Overall, Peary caribou did not fare well in the last half of the 1990s. The High Arctic population is in such deep trouble now that the Committee on the Status of Endangered Species in Canada has recommended the Peary caribou remain on the endangered list. The Peary, however, is not the only population of caribou in North America on the decline. Since the mid- to late-1980s, many of the great herds in North America have been in a free fall.

The Bathurst herd in the central Arctic numbered 472,000 in 1986. Today, it is down to 128,000. The Cape Bathurst herd had 17,500 animals in 1992. Now there are no more than 1,800. Over in Alaska, the Yukon and Northwest Territories, the porcupine caribou herd has declined from 178,000 animals in 1989 to the 123,000 biologists counted the last time they were able to do a comprehensive census. In places like the south-central coast of the Canadian Arctic, there are so few animals left that a recovery may never happen.

EDIT

Initially, Miller was concerned that he may have missed something or done something wrong that summer. A survey 13 years earlier suggested there were as many as 26,000 animals in the High Arctic and as many as 4,000 in the area he was surveying. Only when he searched through the meteorological records for clues to what might have happened did he come up with an explanation. Those records showed that the freezing rain that occurred in fall of 1973 was followed by heavy snow in winter and recurring periods of thawing and freezing the following spring. As a result, much of the Queen Elizabeth Islands had been transformed into a giant, snow-covered skating rink. The ice was likely so thick in most places the animals often couldn't get through to the vegetation. Those that were successful probably spent more energy than they received. Gunn says no one should be surprised that a warmer Arctic may not be good for caribou. Many of the large mammals of the Arctic, she notes, -- the wooly mammoth, Yukon horses, Alaskan camels, short-faced bears and American lions -- all died off during the 8,500 years the climate began warming after the last great ice age ended. Now those animals that are left are adapting to another period of warming that began 150 years ago when the mini-ice age ended around 1850. That natural warming is now being intensified by the emission of greenhouse gases.

EDIT/END

http://www.canada.com/vancouversun/news/westcoastnews/story.html?id=1c9e10a6-d8d5-4d57-abba-c0207fa151cd

Note: this article does discuss cyclical population crashes well-known to scientists. However, the wild card here is warming - specifically, increased incidence of ice making food inaccessible to large ungulates like caribou & musk ox.