Via Dr. Susan Crockford at polarbearscience.com:
Here’s a new resource for cooling the polar bear spin, all in one place. I’ve updated and expanded my previous summary of reasons not to worry about polar bears, which is now two years old. In it, you’ll find links to supporting information (including previous blog posts of mine that provide background, maps and extensive references), although some of the most important graphs and maps have been copied into the summary. I hope you find it a useful resource for refuting the spin and tuning out the cries of doom and gloom about the future of polar bears — please feel free to share. Pdf here of the text below.
This is the 1st anniversary of Canada providing population estimates and trends independent of the pessimistic prognostications of the IUCN/SSC Polar Bear Specialist Group (PBSG) — so let’s celebrate the recent triumphs and resilience of polar bears to their ever-changing Arctic environment.
1) Polar bears are still a conservation success story — with a global estimate almost certainly greater than 25,000, we can say for sure that there are more polar bears now than there were 40 years ago (Fig. 1). Sadly, although completing a global survey was one of the primary objectives of the PBSG at its inception 47 years ago, it has still not provided one. The current PBSG estimate is about 20,000-25,000 bears, although with several subpopulations still uncounted (Fig. 1), the actual figure is almost certainly a good deal higher (e.g. see point #3). Even with this lack of precision, the global estimate is too high to qualify the polar bear as ‘threatened’ with extinction based on current population levels – all of the concerns expressed regarding polar bears are about the future.
2) The most recent status assessment for polar bears, published by Environment Canada in May 2014, shows only two subpopulations are “likely in decline,” down from four listed by the PBSG as declining in 2013 and seven in 2010 (Fig. 2). Baffin Bay earns its ‘likely decline’ status due to suspicions of over-harvesting (so far not confirmed), not sea ice decline. And the recent assessment of Southern Beaufort bears (see point #7 below), which was based on a newly-formulated (i.e. untested) population estimate model that used a truncated data set, recorded a decline acknowledged to have been caused by thick ice conditions in spring, not summer ice declines.
More here: http://polarbearscience.com/2015/02/19/twenty-good-reasons-not-to-worry-about-polar-bears/