A just-released report on the most recent (2016) survey shows Western Hudson Bay polar bear numbers were still stable despite predictions that this subpopulation would be wiped out completely (reduced to zero) due to low Arctic sea ice.

The authors of the report on the August 2016 aerial survey of the Western Hudson Bay polar bear subpopulation (Dyck et al. 2017) state clearly that the only trends they could find were that the number of adult males increased somewhat over 2011 estimates and the number of females either declined or remained stable. The overall population estimate was a bit lower (11% less) compared to the 2011 survey but the difference is not statistically significant. Therefore, the population status must be stable.
2011 estimate: 949 bears (using comparable data, range 618-1280), litter size 1.43
2016 estimate: 842 bears (using comparable data, range 562-1121), litter size 1.63
[cf. Foxe Basin [stable], from 2009-2010 survey (Stapleton et al. 2016) litter size was 1.54]
An 11% decline in WH numbers since 2011 is most definitely NOT the decline to ZERO (extirpation) we were told to expect with Arctic sea ice as low as it has been since 2007 (Crockford 2017, see list of annual minimum extents 2007-2017 here).
Note: The percentage decline from 2011 to 2016 for Western Hudson Bay polar bears is 11%, NOT 18% as claimed recently by Andrew Derocher on twitter: it is not appropriate to compare the official 2011 estimate of 1030 (Stapleton 2014) to the 2016 estimate of 842 because the methods used to generate the estimates were different (Dyck et al. 2017). The authors of the report state that the estimate for 2011 that’s comparable to 2016 is 949.
An 11% decline from 1030 would be 917 bears, a statistically insignificant decline that is also biologically insignificant and therefore, so slight as to indicate a stable population.
https://twitter.com/AEDerocher/status/908423171967139840
Predicted sea ice at 2050 and 2080 shown below (see Crockford 2017 for details):

Quotes, map, and table from the Dyck et al. 2017 report (pdf here) are copied below.
Continue reading
State of the Polar Bear Report 2017 to be released Feb 2017 at press lunch Toronto
My “State of the Polar Bear Report 2017” will be unveiled at a Global Warming Policy Foundation press conference and luncheon in Toronto on Tuesday, 27 February, in celebration of International Polar Bear Day. There will be a video presentation as well.
The report summarizes clear, reliable and concise information on the current state of polar bears relative to historical records. It highlights up-to-date data and research findings in a balanced and factual format that avoids hype and exaggeration, all in one place. It is intended for a wide audience, including scientists, teachers, students, decision-makers and the general public interested in polar bears and Arctic ecology.
The launch will be held on Tuesday 27 February at 11:00am at the Toronto Public Library, Founders’ Room, 789 Yonge St, Toronto, ON M4W 2G8.
Programme
* Welcome (Dr Benny Peiser, Director of the GWPF)
* Introduction: Prof Chris Essex (Chairman of the GWPF’s Academic Advisory Council)
* Short video screening
* Presentation: Dr Susan Crockford (author of the report)
For further information and to schedule interviews, please contact Harry Wilkinson (harry.wilkinson@thegwpf.org)
A copy of the report will be posted on Polar Bear Science Tuesday.
Comments Off on State of the Polar Bear Report 2017 to be released Feb 2017 at press lunch Toronto
Posted in Conservation Status, Life History, Sea ice habitat, Summary
Tagged commentary, facts, polar bear, report, research, review, status, summary, synthesis, unbiased, video