Tag Archives: IUCN

Global polar bear population size is about 28,500 when updates are included

Polar bear numbers have risen since 2005, no matter how you look at it:

Svalbard polar bear Jon Aars_Norsk Polarinstitutt

USGS estimated 24,500 (average) polar bears in 2005.

IUCN estimated 26,500 (average of 22,000-31,000) in 2015
(assessment completed in July, released in November).

Subpopulation surveys completed or reported after July 2015 (Baffin Bay, Kane Basin, Barents Sea) added ~2,000 bears.

This brings the adjusted average total at 2015 to ~28,500.

Crockford 2017_Slide 12 screencap

Explained in full in this published paper, pgs 20-21:

Crockford, S.J. 2017 V3. 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

 

New paper asks: Has recent sea ice loss caused polar bear populations to crash?

A paper published today finds that predictions of polar bear population crashes due to summer sea ice loss are based on a scientifically unfounded assumption.

crockford-2017-title-page-graphic

[The graphic above was created by me from the title page and two figures from the paper]

Specifically, this paper of mine addresses the basic premise upon which predicted population declines linked to modeled habitat loss made by polar bear specialists back in 2006 and 2008 (by the International Union for the Conservation of Nature, IUCN, and the US Fish and Wildlife Service, USFWS), and concludes that when assessed as a testable hypothesis against data collected since then, it must be rejected.

The forum for this paper is PeerJ Preprints,  which I found while looking for recent research papers about ringed seals. I discovered that Canadian ringed seal biologist Steven Ferguson recently used this service, which is free, open access, accepts review commentary, and will show up on Google and Google Scholar searches.

Ferguson et al. 2016. Demographic, ecological and physiological responses of ringed seals to an abrupt decline in sea ice availability. DOI:10.7287/peerj.preprints.2309v1 Pdf here. https://peerj.com/preprints/2309/

I decided that if this publication forum was good enough for Ferguson and his Arctic research community, it was good enough for me.

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 19 January 2017. Doi: 10.7287/peerj.preprints.2737v1 Open access. https://peerj.com/preprints/2737/  (pdf here).

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IUCN Polar Bear Specialist Group website still silent on 2015 Red List assessment

It’s now been 11 months since the IUCN Red List announced the completion of a new conservation assessment for polar bears – but you wouldn’t know that if you visited the website of the IUCN Polar Bear Specialist Group (PBSG).

pbsg-website-notice_home-page-2016-oct-18

Back in May 2016, I wrote to the folks at the IUCN Red List asking them why the PBSG had not yet added a link to their website regarding the 19 November 2015 update to the Red List polar bear assessment (submitted by PBSG members in July 2015), a shortcoming I first notice in December 2015. I also inquired why the IUCN Red List folks were not taking the PBSG to task for their failure to keep the public informed of this new development.

After a wait of more than 6 weeks (23 June), I finally received a reply. The Red List official accepted as reasonable the PBSG excuse that since a link to the IUCN Red List was present on their home page as an icon (here), a direct link to the actual Red List polar bear assessment was not necessary. He was informed by the PBSG that the website upgrade had simply taken longer than expected but that it would be completed by the end of July.

And yet, here it is – almost three months later and still no revised website – and more importantly, still no mention of the 2015 Red List assessment update, see screencap above taken 18 October 2016 (which has been up since 14 January 2016).

Note that my complaint is not that the website upgrade has taken longer than expected (doesn’t it always?) – it’s about the continued refusal to provide a simple link to the 2015 Red List assessment at the top of their “News” feature which sits prominently on their home page.

The PBSG is considered the scientific authority on polar bears and in my opinion, the fact that for 11 months their website has lacked a link to the 2015 Red List assessment (which contains many significant changes, including a larger population estimate, a revised population trend, and a prediction of future change with error bars) raises concerns about transparency, potential bias, and lack of accountability of the PBSG organization – and displays a similar kind of contempt for the public that its chairman revealed back in 2014 when he said that population size estimates were “simply a qualified guess given to satisfy public demand.”

Copies of my email exchange with the Red List associate who answered my inquiry are below – decide for yourself if I’m over-reacting.

UPDATE 22 Nov. 2016: A cursory check of the PBSG website today revealed that a few days ago (16 Nov. 2016) the PBSG Chairman finally did what I have been suggesting for almost a year: post a simple notice and link to the 2015 IUCN Red List polar bear assessment.

A simple line in the NEWS section of the home page:

pbsg-website_home-page-2016-nov-16-news-red-list

They even added a short notice with links to the documents (screen cap below).

pbsg-website-redlist-news-notice_2016-nov-16

Yes, pretty much exactly what I suggested in January. I’d hazard a guess I wasn’t the only one complaining.

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Terrestrial food fight amongst polar bear researchers reflects political differences

With a few big guns on one side and some fringe folk on the other, a dichotomy of opinion has developed amongst polar bear researchers regarding whether or not consumption of land-based foods is making a difference to polar bear survival (or is likely to in the future).

Polar bears eating terrest foods WHB_Rockwell press release

It’s been going on for a while now. Last year, two US Geological Survey members of the IUCN Polar Bear Specialist Group (PBSG) apparently got fed up with the scatter-shot of papers promoting terrestrial foods as a possible salvation for polar bears (e.g. Iles et al. 2013;  Iverson et al. 2014; Rockwell and Gormezano 2013a, 2013b). In April, they published a canon volley of a paper meant to blow all that ‘polar-bears-might-survive’ talk out of the water once and for all (Rode et al. 2015).

Note that although the PBSG didn’t bother to update their website with the IUCN Red List assessment when it came out last November, they had a link up to the USGS terrestrial feeding paper within 16 days (with an editorial summary in the “NEWS” section as well as a listing of the paper in the “RECOMMENDED READING” section). As I suggest below, this difference in treatment may not be a coincidence.

However, another group of non-PBSG researchers  haven’t given up just yet, as shown by the title chosen for the most recent news report (Alaska Dispatch News, 16 June 2016) on the just-finished International Bear Conference:

Want to know how a changing climate is affecting polar bears? Look at what they’re eating.

Apparently, Jeff Welker, a University of Alaska Anchorage researcher who is co-author on two recent papers on the subject of polar bear consumption of terrestrial foods (Tartu et al. 2016 and Rogers et al. 2015), gave a presentation at the conference that raised this topic yet again. His talk came on the heels of an earlier presentation by Todd Atwood, who suggested Southern Beaufort polar bears might benefit from staying onshore to eat left-over whale scraps instead of staying on the sea ice during the summer (even though he had no data to support that opinion – as I discussed in this post).

Here’s the question: is this dispute really about what polar bears eat or don’t eat when they’re on land – or is it symptomatic of the underlying politics of polar bears? [CBC documentary video by that name here]
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PBSG failure to acknowledge 2015 IUCN polar bear update drives the public here

It is now past the 15 June 2016 mark and the IUCN Polar Bear Specialist Group (PBSG) has still not acknowledged the 2015 IUCN Red List update on the status of polar bears. See the screencap below, taken this morning.

PBSG at 16 June 2016

This notice has been up since 14 January 2016 and no reference or link to the November 2015 IUCN Red List update has been posted, even though PBSG members authored the report (pdf here)!

What they may not realize is that their silence just drives people who search the internet looking for up-to-date population and conservation status info on polar bears to this site. My posts on population size and conservation status have been the most popular posts since November.

It’s that kind of attention that has made this site so popular: PolarBearScience will reach 750,000 views within the next couple of weeks (see “Blog Stats” lower right) – that’s right, 3/4 million views in less than four years. More than 400,000 readers have come here since the end of July 2012 to find out what’s really going on in the world of polar bears. Continue reading

Silence of the IUCN Polar Bear Specialist Group on the 2015 IUCN Red List assessment

It’s been six months and still the IUCN Polar Bear Specialist Group has not updated its website with a link to the 2015 IUCN Red List assessment for polar bears, which was made public with some fanfare in November 2015. They are not the only group still ignoring the Red List decision but their silence is the most damning – the IUCN is the parent body of their organization.

On May 7th, I wrote to the IUCN Red List folks (redlist@iucn.org) about this situation (excerpt below) but as yet have received no reply.

PBSG website banner May 10 2016

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Challenging Alaska polar bear research sound bites and bewildering ESA status

Beaufort Sea male polar bear USGS_2005 Amstrup photo

It’s easy to take polar bear research papers at face value but it’s not very scientific. The snappy sound bites provided for the benefit of the media – whether they’re embedded in press releases or in published abstracts – don’t cut it with trained scientists. Trained scientists read the whole report, critically examine the evidence it contains and assess that evidence within the context of previous knowledge. That’s what they are trained to do.

I challenge the superficial summary on the status of Alaskan polar bear populations provided by FactCheck.org journalist Vanessa Schipani.  Schipani disputed a comment made by Alaska Senator Lisa Murkowski that, according to the latest research Alaskan polar bear population numbers are strong and healthy. I’m not especially interested in the political context of the statement, only Schipani’s bald claim that Murkowski’s declaration is false.

I’ve read all the relevant papers in full and I contend that the evidence supports Murkowski’s statement. Schipani is confusing the issue by regurgitating ‘facts’ that don’t tell the truth of the matter. By the sum of accounts, Alaskan polar bear populations are indeed healthy and strong – whether or not this status will continue is an entirely different question. Continue reading