— This is an excerpt from my op ed, To Kill a Polar Bear. You can read the whole article at The Patriot Post. —
Last year, one of my favorite headlines read, “Polar Bears Threatened From Too Much Arctic Ice.” It was based on the work of Dr. Susan Crockford, a zoologist from British Columbia who has studied polar bears for the bulk of her 35-year career. But now, Dr. Crockford has just released a new, in-depth report on the relationship between sea ice and polar bears, entitled Arctic Fallacy. It’s a promising iceberg-of-truth destined to sink a Titanic-load of scientific dross. Let’s dig in:
“She uses her broad background in several scientific fields to question the basic assumption that sea ice is a stable environment in all seasons, even over short time periods,” writes Matthew Cronin, Professor of Animal Genetics at the University of Alaska Fairbanks, in the foreword.
Crockford shows how it’s naturally variable spring ice, not summer ice, that is most critical to the survival of polar bears. She explains,
“Arctic biologists now surprisingly attribute virtually every downturn in population size of Arctic species to declines in summer sea ice blamed on human use of fossil fuels. Shifting the blaming for the devastation caused by thick spring ice onto recent summer ice declines, biologists portray summer ice changes as manifestations of unprecedented, human-caused habitat instability.”
Spring sea-ice thickness is especially important because it “is the period of on-ice birth and nursing for ice-dependent seals and is also when polar bears consume two-thirds of their annual prey.” Crockford says that the most deadly ice variable for both seals and polar bears appears to be thick spring ice, instead of a lack of summer ice.
“More disturbing is that population declines that were clearly caused by thick sea ice conditions in spring are now blamed on summer sea-ice declines,” writes Crockford.
Even when summer ice extent has been less than average, the prediction that polar bears would drop in numbers as a response have proven to be wrong. “While it is true that there have been moderate increases in the length of the ice-free season in regions of the Arctic where the ice usually melts completely in the summer – for example Hudson Bay and the Davis Strait – this has so far changed gradually and polar bear populations are either stable or increasing.”
The report is very well documented, interesting, and worth your time to read in its entirety.
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