Caribou populations are back up; in retrospect, your iPhone charger usage may not have been as big a factor as people shooting high-powered bullets through vital areas of 20% of the cows annually

Caribou populations back from the brink - North - CBC News

The Bluenose East herd is back up over 100,000 animals. Yukon's Porcupine herd is approaching 1980s levels.

And preliminary surveys in 2010 and 2011 of the Bathurst herd hint the free fall may have bottomed out.
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Factors such as climate change, which upsets the delicate timing of northern ecosystems, and industrial development, which takes out sections of their range, have been blamed for some of the decline. But the two biggest factors were poor calf survival and hunting.

Good weather for the last couple of years has decreased calf mortality. And Adamczewski points out that all the recovering herds enjoy one factor in common — hunting restrictions.
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In a recently published paper, Adamczewski and three co-authors estimated the annual aboriginal harvest from the Bathurst herd alone was between 4,000 and 7,000 animals, mostly cows. Best estimates suggest that about 20 per cent of the cows were being killed every year, making it the most heavily hunted herd in the N.W.T.

"They were getting hammered," Adamczewski said.

But when hunting restrictions came in, the Dene could no longer take as many animals as they wanted. It was a huge problem because caribou is on the supper table several times a week in the North and hunting is a central part of what it means to be Dene.