IUCN Red Book officials forced scientific standards on polar bear predictive models

As I reported Thursday, the IUCN announcement of a new Red List assessment for polar bear got the usual overwrought attention from international media outlets. However, not one of these contained a quote from a polar bear biologist.


Steven Amstrup, science spokesperson for activist conservation organization Polar Bears International, has so far had nothing to say to the media. Yet, Amstrup was a co-author of the IUCN Red List report. Not until late in the day following the release of the report did his his organization’s website post a short, bland news report (“Climate Change Still Primary Threat to Polar Bears”).

Similarly, Ian Stirling, Andrew Derocher, Nicholas Lunn (also a co-author of the IUCN Red List report), and former WWF employee Geoff York – who are usual go-to guys for polar-bears-are-all-going-to-die media frenzies – have so far been silent and invisible on this issue.

In addition, while the IUCN press release [backup here: 2015 IUCN Red List press release_Nov 19 2015] included a quote from IUCN Polar Bear Specialist Group (PBSG) chairman Dag Vongraven, as of this morning (21 November, PST), the website of the PBSG contains no mention of this decision – no item in the “News” category  and, more importantly, no update of the status table  or global estimates to reflect the changes contained in the report  (even though they obviously knew it was coming months ago: the report was submitted to the IUCN Red List 27 August 2015).

In my opinion, this silence says it all: polar bear specialists know this assessment is a severe de facto critique of their 2008 assessment (as well as Amstrup’s predictive models) and it’s a big step backwards for their conservation activism. I expect they are silent because they are royally pissed off.

However, this assessment is good news because finally, some standards of scientific rigor have been applied to polar bear predictive models – even though the PBSG were still been allowed to pretend that summer sea ice coverage is critical to polar bear health and survival (Crockford 2015). 

IUCN polar bear experts were forced by the IUCN standards committee to acknowledge the great deal of uncertainty in their population estimates and predictive models. As I pointed out in my first post on this decision, this 2015 assessment eliminates any risk of extinction from the discussion of polar bear conservation status. The media needs to catch up. 

Yes, the status of Vulnerable was upheld but there is no projection contained in the report beyond 2050 (a limit of 3 generations beyond 2015) and it states explicitly that the risk of a population decline of 80% or greater by 2050 is virtually zero (pg. 16).

The IUCN standards committee have forced polar bear specialists to admit there is only a 70% chance that numbers will decline by 30% over the next 35 years: only slightly higher than a 50:50 chance. That means there is a 30% chance that the numbers WILL NOT decline by 30% over the next 35 years and no chance of extinction by 2050. See for yourself in the copies of the report and links to the online IUCN Red List assessment below.

Polar bears in 2015 are listed as Vulnerable by the IUCN only on the basis of a possible (70% chance) decline in population numbers, not their current status: the current population trend is stated as UNKNOWN.

Screencap from the IUCN Red List for polar bears:

IUCN Red List PB trend Nov 20 2015

The PBSG were also forced to include estimates from subpopulations they dropped from their status table years ago (East Greenland, Chukchi Sea dropped in 2005, and Laptev Sea dropped in 2009), which I added back in for my graph on population status last year. They were also forced to include the new estimate generated by Russian biologists for the Kara Sea, which earlier this year, they implied was not good enough for their high standards.

However, the IUCN Red List Standards Committee essentially told them at a meeting last summer: you cannot make a predictive assessment of the total population without population estimates from ALL regions. So, all those numbers had to be included.

One final thought about population estimates – I found it very odd that results from the recent survey of Baffin Bay, which concluded the fall of 2013, and promised “sometime next year” [i.e. 2014], were not included in this critical document. Instead, the IUCN Red List assessment models used Baffin Bay data from 1997 (pg. 8 in the suppl). Does that mean we can expect to find, when the results are finally published, that the population size has increased? Time will tell.

All this came about because, in contrast to the last Red List assessment (2008), PBSG members were not permitted to be official reviewers of the document and they had help in compiling the assessment from biological statisticians and other outside specialists. Compare below:

2008 Red List assessment details2008 IUCN Red List PB report details

2015 Red List assessment details2015 IUCN Red List Pb report details

Citation for the report:
Wiig, Ø., Amstrup, S., Atwood, T., Laidre, K., Lunn, N., Obbard, M., Regehr, E. & Thiemann, G. 2015. Ursus maritimus. The IUCN Red List of Threatened Species 2015: e.T22823A14871490. Published online here;
PDF copy of that report page: 2015 IUCN Red List Ursus maritimus (Polar Bear) – www_iucnredlist_org_Nov 18 2015

PDF of supplement, as issued: 2015 IUCN Red List report 22823_Ursus_maritimus; PDF of supplement, marked by SJC: 2015 IUCN Red List report MARKED 22823_Ursus_maritimus

Other references
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.

Matishov, G.G., Chelintsev, N.G., Goryaev, Yu. I., Makarevich, P.R. and Ishkulov, D.G. 2014. Assessment of the amount of polar bears (Ursus maritimus) on the basis of perennial vessel counts. Doklady Earth Sciences 458 (2):1312-1316. [paywalled]

[Original Russian Text © G.G. Matishov, N.G. Chelintsev, Yu.I. Goryaev, P.R. Makarevich, D.G. Ishkulov, 2014, published in Doklady Akademii Nauk, 2014, Vol. 458, No. 6, pp. 706–710.] Lead author email: matishov@mmbi.info]

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