Specialists mum on low Chukchi Sea polar bear habitat this summer and fall

You may or may not have noticed that even though Chukchi Sea ice coverage has been way below average this melt season, there has been no hue-and-cry about poor suffering Chukchi polar bears. That’s because polar bear biologist’s own research has shown that the health and survival of these bears has not been negatively impacted by low summer sea ice. There may be threats from poaching in Russia, but not lack of summer sea ice.

Chukchi vs Beaufort ice at 29 Oct 2015_polarbearscience

As of this date, developing sea ice is only just approaching Wrangel Island, a major polar bear denning region in the Chukchi Sea, see maps below (Ovsyanikov 2006).

Yet, polar bear specialists insist that neighbouring Beaufort Sea bears – who endure a much shorter open-water season – are in peril of extinction because of scarce summer sea ice.

NSIDC’s Masie sea ice data graphs for Arctic regions (see below) show the Beaufort Sea is maxed out for ice coverage while Chukchi Sea is the lowest it has been in the last five years.



Here is how that sea ice looks on the landscape (as of 8 November 2015): the Beaufort Sea totally ice-covered, the Chukchi Sea still open water.

masie_all_zoom_4km 2015_Nov 8

Oddly, the agenda-driven “Circumpolar Action Plan” developed by polar bear specialists declares these two regions to be so similar in sea ice ecology that results from one can be used as a proxy the other in predictive models (Vongraven et al. 2012; Vongraven 2013). That Circumpolar Action Plan has now been accepted by all Arctic nations in a meeting of polar bear range states in September 2015 (documents here: pdf of final agreement; Q & A;fact sheet; meeting outcome document).

Talk about a science boondoggle. Below are the Arctic ecoregions defined in the Circumpolar Action Plan compared to the polar bear subpopulation regions as defined by the IUCN Polar Bear Specialist Group (PBSG):

Sea ice ecoregions vs EC subpopoulations_PolarBearScience_March 22 2015

Of course, the decision that the Chukchi Sea and the Beaufort Sea are ecological equivalents was made before research showed this was clearly not the case (Amstrup et al. 2007, 2011).  Although the Chukchi Sea polar bear subpopulation has been deemed “data deficient” due to lack of recent population counts, recent research showed Chukchi bears were in excellent condition and reproducing well (good indicators of a thriving population) despite recent extended open-water seasons (Rode and Regehr 2010; Rode et al. 2013, 2014).

But instead of admitting that the Arctic “ecoregions” concept was flawed, they made some vague excuses and carried on with the plan.

Which means, henceforth, the Southern Beaufort polar bears that are known to suffer recurring bouts of starvation and population declines as a result of thick spring ice conditions every 10 years or so (Crockford 2015, summarized here) will get virtually all of the available research funds for annual surveys. Predictive models and management policies based on the the results will be applied to Chukchi Sea bears.

What could go wrong?

Relevant References
Amstrup, S.C. 2011. Polar bears and climate change: certainties, uncertainties, and hope in a warming world. Pgs. 11-20 in R.T. Watson, T.J. Cade, M. Fuller, G. Hunt, and E. Potapov (eds.), Gyrfalcons and Ptarmigan in a Changing World, Volume 1. The Peregrine Fund, Boise, Idaho. http://dx.doi.org/10.4080/gpcw.2011.0100

Amstrup, S.C., Marcot, B.G., and Douglas, D.C. 2007. Forecasting the rangewide status of polar bears at selected times in the 21st century. Administrative Report. U.S. Geological Survey, Alaska Science Center, Anchorage, Alaska, USA.

Crockford, S.J. 2015. “The Arctic Fallacy: sea ice stability and the polar bear.” GWPF Briefing 16. The Global Warming Policy Foundation, London. Pdf here.

Rode, K.D., Douglas, D., Durner, G., Derocher, A.E., Thiemann, G.W., and Budge, S. 2013. Variation in the response of an Arctic top predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. Oral presentation by Karyn Rode, 28th Lowell Wakefield Fisheries Symposium, March 26-29. Anchorage, AK. Abstract below, pdf here.

Rode, K.D., Regehr, E.V., Douglas, D., Durner, G., Derocher, A.E., Thiemann, G.W., and Budge, S. 2014. Variation in the response of an Arctic top predator experiencing habitat loss: feeding and reproductive ecology of two polar bear populations. Global Change Biology 20(1):76-88. http://onlinelibrary.wiley.com/doi/10.1111/gcb.12339/abstract 

Rode, K. and Regehr, E.V. 2010. Polar bear research in the Chukchi and Bering Seas: A synopsis of 2010 field work. Unpublished report to the US Fish and Wildlife Service, Department of the Interior, Anchorage. pdf here.

Ovsyanikov, N.G. 2006. Research and conservation of polar bears on Wrangel Island. pg. 167-171, in Aars, J., Lunn, N. J. and Derocher, A.E. (eds.), Polar Bears: Proceedings of the 14th Working Meeting of the IUCN/SSC Polar Bear Specialist Group, 20-24 June 2005, Seattle, Washington, USA. Occasional Paper of the IUCN Species Survival Commission 32. IUCN, Gland (Switzerland) and Cambridge (UK). http://pbsg.npolar.no/en/meetings/ Pdf here.

Vongraven, D., Aars, J., Amstrup, S., Atkinson, S.N., Belikov, S., Born, E.W., DeBruyn, T., Derocher, A.E., Durner, G., Gill, M., Lunn, N., Obbard, M., Omelak, J., Ovsyanikov, N., Peacock, E., Richardson, E., Sahanatien, V., Stirling, I., Wiig, Ø. 2012. A circumpolar monitoring framework for polar bears. Ursus 23 (sp2): 1-66. http://www.bioone.org/doi/abs/10.2192/URSUS-D-11-00026.1

Polar bears (Ursus maritimus) occupy remote regions that are characterized by harsh weather and limited access. Polar bear populations can only persist where temporal and spatial availability of sea ice provides adequate access to their marine mammal prey. Observed declines in sea ice availability will continue as long as greenhouse gas concentrations rise. At the same time, human intrusion and pollution levels in the Arctic are expected to increase. A circumpolar understanding of the cumulative impacts of current and future stressors is lacking, long-term trends are known from only a few subpopulations, and there is no globally coordinated effort to monitor effects of stressors. Here, we describe a framework for an integrated circumpolar monitoring plan to detect ongoing patterns, predict future trends, and identify the most vulnerable polar bear subpopulations. We recommend strategies for monitoring subpopulation abundance and trends, reproduction, survival, ecosystem change, human-caused mortality, human–bear conflict, prey availability, health, stature, distribution, behavioral change, and the effects that monitoring itself may have on polar bears. We assign monitoring intensity for each subpopulation through adaptive assessment of the quality of existing baseline data and research accessibility. A global perspective is achieved by recommending high intensity monitoring for at least one subpopulation in each of four major polar bear ecoregions. Collection of data on harvest, where it occurs, and remote sensing of habitat, should occur with the same intensity for all subpopulations. We outline how local traditional knowledge may most effectively be combined with the best scientific methods to provide comparable and complementary lines of evidence. We also outline how previously collected intensive monitoring data may be sub-sampled to guide future sampling frequencies and develop indirect estimates or indices of subpopulation status. Adoption of this framework will inform management and policy responses to changing worldwide polar bear status and trends.

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; available online here: polarbearforum2013.ru/data/presentations/5_1.pdf‎

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