Status of Canadian polar bears updated map from Environment Canada

During a meeting of polar bear range states (Canada, Russia, Greenland, Norway, and the USA) in late January 2018 to discuss conservation issues, Canada — home to ~2/3 of the world’s polar bears — included in its presentation an updated population status and trend map approved by the Polar Bear Technical Committee in its presentation. This 2017 map replaces one from 2014 but is not yet available on the Environment Canada website.

Lunn et al 2016 EA cover image WH bear

UPDATE 11 June 2018: More recent versions of population and status assessment maps, published by Environment Canada 6 June 2018, conclude Southern Hudson Bay and Western Hudson Bay subpopulations have “likely declined.” See 11 June post here for more details and copies of the maps.

Canada Polar Bear Status at 2017 PBTC_cropped from slide

The new map confirms the conclusion from a recent study that Baffin Bay is ‘likely stable’ and Kane Basin has ‘increased’ (although the colour scheme choice makes it hard to tell), and Davis Strait is still listed as ‘likely increased’ (due to ample prey and sea ice during the critical spring feeding period — as even The Guardian is willing to concede (24 May 2018)). It also shows the boundary change between the Southern and Northern Beaufort Sea subpopulations now provisionally accepted by the IUCN Polar Bear Specialist Group.

Western Hudson Bay is still considered ‘likely stable’ despite the handwringing from researchers (e.g. here and here) who put advocacy ahead of science.

That leaves only one subpopulation — Southern Beaufort — as ‘likely decreased.’ But as I’ve argued before, the Southern Beaufort is subject to unique periodic sea ice conditions that cause temporary population fluctuations: what goes on there is not symptomatic of the Arctic overall (Crockford 2018:4, 12).

-7 out of 13 subpopulations are stable, likely stable, increased, or likely increased

-only one is likely reduced (Southern Beaufort)

-5 out of 13 subpopulations are data deficient

-local Inuit (traditional knowledge) consider all 13 to be stable or increased

Three of the data deficient subpopulations (Gulf of Boothia, Viscount Melville, and McClintock Channel) have on-going surveys that should yield up-dated status information shortly (Crockford 2018).

Given the above, there is no reason to suppose that subpopulations that haven’t had a recent survey would change the picture.

With more than half of Canada’s subpopulations either stable or increasing in what are considered by some (Amstrup et al. 2007; Vongraven 2013) to the be most vulnerable regions of the Arctic, polar bears are clearly doing well in Canada despite the abrupt decline in summer sea ice since 2007 that has more or less continued to 2017 (Crockford 2017; see also discussion here).

Sea ice Sept 1979-2017 graph NSIDC

References

Amstrup, S.C., Marcot, B.G. & Douglas, D.C. 2007. Forecasting the rangewide status of polar bears at selected times in the 21st century. US Geological Survey. Reston, VA. Pdf here

Crockford, S.J. 2017. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 2 March 2017. Doi: 10.7287/peerj.preprints.2737v3 Open access. https://doi.org/10.7287/peerj.preprints.2737v3

Crockford, S.J. 2018. State of the Polar Bear Report 2017. Global Warming Policy Foundation Report #29. London. pdf here.

Environment Canada. 2018. Polar bear conservation and management in Canada: 2015-2017 update. Meeting of the Parties to the Agreement on the Conservation of Polar Bears February 2-4, 2018, Fairbanks, Alaska, U.S.A. Pdf here.

Vongraven D. 2013. Circumpolar monitoring framework for polar bears. Presentation 5.1 at the International Polar Bear Forum, December 3-6, Moscow. Download pdf here

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