More global warming propaganda from WWF and Reuters; they find that polar bear cubs can die of hypothermia when hit by storms during long-distance swims

More polar bear cubs die as Arctic ice melts | Reuters

"Climate change is pulling the sea ice out from under polar bears' feet, forcing some to swim longer distances to find food and habitat," said Geoff York of World Wildlife Fund, a co-author of the study.
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To gather data, researchers used satellites and tracked 68 polar bear females equipped with GPS collars over six years, from 2004 through 2009, to find occasions when these bears swam more than 30 miles at a time.

There were 50 long-distance swims over those six years, involving 20 polar bears, ranging in distance up to 426 miles and in duration up to 12.7 days, according to a paper for presentation on Tuesday at the International Bear Association Conference in Ottawa, Canada.

At the time the collars were put on, 11 of the polar bears that swam long distances had young cubs; five of those polar bear mothers lost their cubs during the swim, representing a 45 percent mortality rate, the study found.

Cubs that didn't have to swim long distances with their mothers had an 18 percent mortality rate, the study said.
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"They're a lot like us," York said in a telephone interview. "They can't close off their nasal passages in rough waters. So for old bears or young bears alike, if they're out in open water and a storm hits, they're going to have a tough time surviving."
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"Young bears don't have very much fat and therefore they aren't very well insulated and cannot cope with being in cold water for very long," Amstrup said in the same telephone conversation.

1. It looks like this study was carefully set up in an attempt to find drowning polar bears for propaganda purposes, but from their perspective, it was a failure.
After studying 68 adult females over six years, apparently zero of the adults drowned, but they did document that polar bears can swim for 426 miles and/or 12.7 days!

2.  I'm not convinced that even the five missing cubs actually died during the swims.  They don't tell us that the cubs were very young during the swims; how do we know that one or more of the uncollared-but-missing cubs didn't survive?  Out of 11 total swimming cubs, the difference between a 45% and 18% "normal" mortality rate is only three total cubs.

3. How do we actually know that "more" polar bear cubs die as Arctic ice melts?  What percent of polar bear cubs died when swimming one hundred, one thousand, or ten thousand years ago?  How do we know that carbon dioxide made these bears decide to swim?