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Originally Posted by Bullseye  Well the Polar Bear bit is true, think it's something like (and at this time of night I'm not looking it up),17 populations increasing,2 stable and 2 dwindling. |
Actually according to the IUCN polar bear group its a total of 19 populations of which 5 are declining , 5 are thought to be stable (though at risk of decline), 2 are increasing (both of which are very near land) , 6 have deficient data and 1 has no data at all
they also say
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Because polar bears feed almost exclusively on ice-associated seals, changes in the sea ice that affect access to prey will have a negative effect on the bears.....Polar bears are totally reliant on the sea ice as their primary habitat. If climate change alters the period of ice cover, bears may be forced on shore for extended periods and forced to rely on stored fat. If these periods become excessively long, mortality will increase. Such changes are thought to be occurring in western Hudson Bay. Further, if the ice changes in character such that there is more open water, young cubs which are unable to swim long distances may suffer greater mortality. Sea ice is also used for access to den areas and if ice patterns change, existing den areas may be unreachable. Another factor is that in some areas, warmer temperatures and higher winds may reduce ice thickness and increase ice drift. Because polar bears must walk against the moving ice (like walking the wrong way on an escalator) increased ice movements will increase energy use and reduce growth and reproduction.
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which shows the potential for climate change impact on all polar bear populations even those which are currently stable.
full info here
IUCN/SSC Polar Bear Specialist Group
mind you the authors of the peice paul is complaining about are right that polar bear populations have more than doubled since the 50s - arround 10,000 in 56, now arround 25,000 (down from over 27,000 in the early ninetys) - but they overlook the rather large fact that the bears were being heavily hunted prior to 56, but are now protected. There are no reliable population figures prior to the 56 study, but annectdotal evidence suggests that the population was a lot higher than 25,000 prior to the advent of the repeating rifle.