nature
Some "science-affirmers" of man-made climate change argue that melting Arctic Ocean sea ice will doom polar bears. Why? Because the bears hunt seals on the ice. No ice, no seals to munch on. It is true that the extent of summer Arctic Ocean sea ice has been on a downward trend for the past several decades, but how are polar bears really faring?
In its article, "Will Polar Bears Become Extinct?," the BBC reports:
"The best estimates we've got indicate that we'll probably lose somewhere around two-thirds of the world's bears somewhere around mid-century, just based on the simple fact that we're losing sea ice," says Andrew Derocher, a professor of biological sciences at the University of Alberta and past chair of the International Union for the Conservation of Nature's (IUCN) Polar Bear Specialist Group. … In the Hudson Bay, when Derocher first started doing research in the region there were 1200 bears. Now there are barely 800. "The current status is the numbers have dropped by about a third," Derocher says. "It certainly doesn't seem like it's on a continuous precipitous climb."
However, in February 2014, other researchers published a study in Biological Conservation that found no firm evidence for such a precipitous decline in the Hudson Bay region. In addition, the Polar Bear Technical Committee of Environment Canada published a map in June 2014 showing estimates of various subpopulations of polar bears. The committee estimates there are between 1, 000 and 1,500 bears in Western Hudson Bay (WH) and that the population is likely stable. See map below.
Environment Canada
Click on map link above for a larger map.
Keep in mind that counting wild animals in remote areas is always a difficult and fraught enterprise and people are likely to see what they want to see.
Hat tip to Marian Tupy and Matt Ridley.
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