Tag Archives: threatened

Amstrup & colleages can’t refute my critique of their 2007 polar bear survival model, Part 2

Polar bear specialists Andrew Derocher and Steven Amstrup recently spent inordinate energy trying to refute the opinion piece I’d written for the Financial Post in celebration of International Polar Bear Day last month, ignoring my fully referenced State of the Polar Bear Report for 2017 that was released the same day (Crockford 2018) and the scientific manuscript I’d posted last year at PeerJ Preprints (Crockford 2017).

polar_bear_USFWS_fat Chukchi Sea bear

Their responses use misdirection and strawman arguments to make points. Such an approach would not work with the scientific community in a public review of my paper at PeerJ, but it’s perfect spin for the self-proclaimed “fact-checking” organization called Climate Feedback. The result is a wildly ineffective rebuttal of my scientific conclusion that Amstrup’s 2007 polar bear survival model has failed miserably.

This is Part 2 of my expose, see Part 1 here.
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Amstrup & colleages can’t refute my critique of their 2007 polar bear survival model, Part 1

It’s been more than a year since I first published my scientific manuscript at PeerJ Preprints (a legitimate scientific forum) on the failure of Amstrup’s 2007 USGS polar bear survival model (Crockford 2017), a year waiting in vain for the polar bear community to comment. They either couldn’t be bothered or knew they couldn’t refute it – I haven’t known for sure which. But I do now.

Beaufort Sea male polar bear USGS_2005 Amstrup photo

Polar bear specialists didn’t comment because they couldn’t refute it in the scholarly manner required by PeerJ: all they could do is tear it down with derision, misdirection and strawman arguments.

I know this because the damage control team for the polar-bears-are-all-going-to-die-unless-we-stop-using-fossil-fuels message wasn’t activated over my fully-referenced State of the Polar Bear Report for 2017 (Crockford 2018) released on International Polar Bear Day last month, but for a widely-read opinion piece I’d written for the Financial Post published the same day (based on the Report) that generated three follow-up radio interviews.

By choosing to respond to my op-ed rather than the Report or my 2017 paper, biologists Andrew Derocher and Steven Amstrup, on behalf of their polar bear specialist colleagues1, display a perverse desire to control the public narrative rather than ensure sound science prevails. Their scientifically weak “analysis” of my op-ed (2 March 2018), published by Climate Feedback (self-proclaimed “fact checkers”), attempts damage control for their message and makes attacks on my integrity. However, a scientific refutation of the premise of my 2017 paper, or The State of the Polar Bear Report 2017, it is not (Crockford 2017, 2018).

Derocher further embarrasses himself by repeating the ridiculous claim that global polar bear population estimates were never meant for scientific use, then reiterates the message with added emphasis on twitter:

Derocher tweet 2018 Feb 28 quote

Just as the badly written Harvey et al. (2017) Bioscience paper said more about the naked desperation of the authors than it did about me or my fellow bloggers, this attempt by the polar bear community’s loudest bulldogs to discredit me and my work reveals their frustration at being unable to refute my scientifically supported conclusion that Amstrup’s 2007 polar bear survival model has failed miserably (Crockford 2017).

Part 1 of my detailed, fully referenced responses to their “analysis” of my op-ed are below.  Part 2 to follow [here]. Continue reading

Polar bear specialists double-down on message of future starving bears

The really significant content of a new paper being heavily-hyped by the media1 is what wasn’t said rather than what the authors discovered about metabolic rates and weight maintenance of a small sample of nine Southern Beaufort Sea bears in 2014 to 2016 (Pagano et al. 2018; Whiteman 2018).

Pagano et al. 2018 photo released to press 2

This paper does not document starving or dying bears but merely found some (5/9) that lost weight when they should have been gaining, given that early April is the start of the ringed seal pupping season (Smith 1987) and the intensive spring feeding period for polar bears (Stirling et al. 1981).

The question is, why were Southern Beaufort Sea polar bears off Prudhoe Bay (see map of the study area below), still hunting and capturing only adult and subadult ringed seals from sea ice leads when newborn ringed seal pups and their mothers should have been plentiful and relatively easily available in their birth lairs on the sea ice (see below)?

Ringed seal lair_snow and ice thickness_PolarBearScience_sm

“Using video collar data, we documented bears’ hunting behavior and foraging success. Bears used sit-and-wait tactics to hunt seals 90% of the time, and stalking comprised the remaining 10% of hunts (movies S1 to S4) (19). Bears that successfully killed and ate adult or subadult ringed seals either gained or maintained body mass, whereas bears that only scavenged or showed no evidence of eating lost mass.”

There was no discussion in the paper of ringed seal birth lairs, or sea ice conditions at the time of the study, but several mentions about what might happen in the future to sea ice and potential consequences for polar bears. The press release did the same.

However, as you’ll see by the sea ice thickness maps below, there may be good reason for the lack of ringed seal lairs, and a general lack of seals except at the nearshore lead that forms because of tidal action: the ice just a bit further offshore ice looks too thick for a good crop of ringed seals in all three years of the study. This is reminiscent of conditions that occurred with devastating results in the mid-1970s and mid-2000s (Burns et al. 1975; Cherry et al. 2009; Harwood et al. 2012, 2015; Pilfold et al. 2012; Stirling 2002, Stirling et al. 1987). Those events affected primarily bears in the eastern half of the Southern Beaufort and were almost certainly responsible for the recorded decline in SB bear numbers in the 2001-2010 survey (Bromaghin et al. 2015; Crockford 2017; Crockford and Geist 2018).

It seems very odd to me that Pagano and colleagues suggested no reasons for the unexpectedly poor showing of polar bear hunting success during their study except a bit of hand-waving about higher-than-we-thought metabolic rates in the bears. For years, I’ve worried that the inevitable next episodes of thick Southern Beaufort spring ice would cause problems for polar bears and seals but we wouldn’t know it because whatever effects were documented would be blamed on reduced summer ice: I suspect that time may have come.

Pagano et al. 2018 polar bear fat and energy fig 1

Figure 1 from Pagano et al. 2018 cropped to show only the study area off Alaska.

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Retraction request to Bioscience: FOIA emails document another harsh criticism of Amstrup’s 2007 polar bear model

Today I sent a letter to the editors of the journal Bioscience requesting retraction of the shoddy and malicious paper by Harvey et al. (Internet blogs, polar bears, and climate-change denial by proxy) published online last week.

The letter reveals information about the workings of the polar bear expert inner circle not known before now, so grab your popcorn.

Harvey et al. 2018 in press climate denial by proxy using polar bears_Title

I have copied the letter below, which contains emails obtained via FOIA requests to the US Geological Survey and the US Fish and Wildlife Service by the Energy and Environment Legal Institute, E&E Legal, and the Free Market Environmental Law Clinic (USFWS request; USGS request) and sent to me by lawyer Chris Horner in 2014, unsolicited. I reveal some of them now, with his permission (most of the emails are boring, involving mostly technical topics not relevant to anything, as might be expected).

The emails in question, sent in 2014, pertain to preparations by three members of the Polar Bear Specialist Group for the IUCN Red List assessment due in 2015 (Kristin Laidre, University of Washington, Eric Regehr, US Fish and Wildlife Service, and Østein Wiig, Museum of Natural History, University of Olso), and Steven Amstrup (formerly head of the polar bear research at the US Geological Survey, now “head scientist” for conservation organization Polar Bears International.

They include frank discussions about a harsh critique of Amstrup et al.’s 2007 report and 2008 paper used to support listing polar bears as ‘threatened’ on the US Endangered Species List. The criticisms come from modeling expert and chair of the IUCN Red List Standards and Petitions Subcommittee (which develops guidelines for threatened and endangered species assessments, and evaluates petitions against the red-listing of these species), H. Resit Akçakaya. The IUCN is the world’s leading conservation organization, of which the PBSG is a part.

These records are a damning indictment that the “best available science” was not used to assess conservation status of polar bears under the ESA in 2008 and 2014 and show that I am not the only scientist who thinks Amstrup’s model is fatally flawed. The letter is copied in full below, the emails are copied at the end. A file of all of the entire pertinent email thread is available as a pdf below. Here’s a sample:

Wiig to Laidre_9 May 2014 follow up to Lunches with Resit_first part_redacted highlighted

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Published essay: the conservation fiasco that is the ESA listing of polar bears

In early October, the US Fish & Wildlife Service reversed its 2011 decision to list Pacific walrus as ‘threatened with extinction’, saying they could not “determine with certainty that walruses are likely to become endangered “in the foreseeable future.” [details below]

I have argued that the 2008 decision by the USFWS to list polar bears as ‘threatened’ is similarly lacking in certainty (Crockford 2017) and as for walrus, the previous determination of ‘threatened’ for polar bears was premature and should be reversed.

Conservation Fiasco_lead photo_WINTER 2017 RANGE

A prominent biology colleague and I recently put it this way in a newly published essay:

“Is it ethical or fair to the many citizens impacted directly and indirectly by the 2008 polar bear ruling for the FWS to allow polar bears to remain on the Endangered Species List?”

Read our piece in the winter 2018 issue of RANGE Magazine (open access), authored by myself and Dr. Valerius Geist, professor emeritus of environmental science at the University of Calgary, Alberta.

Crockford, S.J. and Geist, V. 2018. Conservation Fiasco. Range Magazine, Winter 2017/2018, pg. 26-27. Pdf here.

PS. You’ll find an excellent piece on wildfires by biologist Jim Steele in the same issue.

See also 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

Details on the USFWS decision on the walrus is below. Note that like the walrus, if ESA protection on the polar bear was reversed, the bears would still be strongly protected under the Marine Mammal Protection Act (as they have been since 1972), and like the walrus, polar bears have shown an ability to adapt that was not foreseen in 2007 (as evidenced by their failure to die off droves in response to recent sea ice declines).

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Experts talk of their bleak future, W Hudson Bay polar bears get earliest freezeup in decades

It seems that Churchill residents and visitors woke up this morning to find most local polar bears had left to go hunting — on the sea ice that supposedly doesn’t exist. Right in the middle of the Polar Bear Week campaign devised by Polar Bears International to drum up donation dollars and public sympathy for polar bear conservation!

Polar bear on the sea ice_Churchill_8 Nov 2017_Explore dot org cam my photo 2Frigid temperatures and north winds last night helped the process along, but this early freeze-up has been in the works for almost a week. From what I can ascertain, it appeared the only bears around onshore today were a mother with her young cub moving out towards the ice (females with cubs are usually the last to move offshore, probably to reduce the risk of encounters with adult males who might kill the cubs).

Tundra Buggy cams at Explore.org have been showing markedly fewer bears today and those that have been seen were on the ice (see above and below) or heading out to it.

The chart below is for yesterday (7 November), before the cold and north winds hit the region. It shows the concentration of ice that’s >15 cm thick.

Hudson Bay North 2017 concentration Nov 7

The chart for 8 November is below, after the storm.

Hudson Bay North daily ice concentration 2017_Nov 8

This is ice thick and extensive enough for polar bears to go hunting. Some bears almost certainly left shore yesterday, with the rest following quickly on their heals today. There are sure to be some stragglers left ashore that will leave over the next few days but the fact remains: there is sea ice to be had for those polar bear willing to start hunting.

Watch polar bear on the WHB sea ice below (screen caps below – and one above – were taken the afternoon of 8 November, from the Tundra Buggy Cam live feed near Churchill).

Polar bear on the sea ice_Churchill_8 Nov 2017_Explore dot org cam my photo 3

Keep in mind that in the 1980s, bears left for the ice on 8 November, on average. That means we’re back to a 1980s freeze-up scenario, at least for this year.

Funny how no one bothered to mention the potential for an early freeze-up to the media last week, when scientist were so eager to talk about the imminent demise of WHB bears. And funny that Polar Bears International hasn’t tweeted a word today about the famous Churchill bears having enough sea ice to go hunting, smack in the middle of Polar Bear Week.

Yes, the “Save Our Sea Ice” PBI rallying cry sounds a bit hollow with sea ice as far as the eye can see off Churchill today. But will anyone in the mainstream media point out the irony?

See charts below for years back to 2004, on this date (2005 missing for some reason), to compare to the above 8 November image (2004 is as far back as the archive goes).

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Twenty reasons not to worry about polar bears, the 2017 update

Cover image_Twenty Reasons_polarbearscienceJust in time for Polar Bears International’s self-proclaimed fall Polar Bear Week (5-11 November 2017), here’s a new resource for cooling the polar bear spin. I’ve updated my 2015 summary of reasons not to worry about polar bears, which is now more than two years old. In this new version, you will find links to supporting information, including published papers and fully referenced blog posts of mine that provide background, maps and bibliographies, although some of the most important graphs and maps have been reproduced here. I hope you find it a useful resource for refuting the pessimism and prophecies of catastrophe about the future of polar bears. Please feel free to share it.

As global leaders meet in Bonn for COP23 (6-17 November 2017), it’s time to celebrate the proven resilience of polar bears to their ever-changing Arctic environment.

Twenty Reasons: the bullet points

  1. Polar bears are still a conservation success story: there are more polar bears now than there were 40 years ago.
  2. Fewer populations are in decline than in 2010 (only one, officially) and only six are data deficient (down from nine).
  3. Abrupt summer sea ice decline has not affected polar bear numbers as predicted: even though sea ice levels dropped to mid-century levels in 2007, the expected decimation of polar bears failed to occur.
  4. The Chukchi Sea population is thriving despite a pronounced lengthening of the ice-free season since 2007.
  5. Less sea ice in the summer in the Chukchi Sea has meant a healthy prey base for polar bears because ringed seals feed primarily in the ice-free season.
  6. Polar bears have shown themselves to be adaptable to changing ice conditions in several regions.
  7. Southern Beaufort numbers have rebounded since the last survey count.
  8. Barents Sea numbers have probably increased since 2005 and have definitely not declined despite much less sea ice cover.
  9. There is no evidence that record-low summer sea ice in 2012 had a harmful effect on Southern Beaufort bear numbers.
  10. Other species are being negatively impacted by high polar bear numbers, especially nesting sea birds and ducks.
  11. Western Hudson Bay population numbers have been stable since 2004, despite what scientists are telling the media.
  12. Hudson Bay sea ice has not changed since about 1999: breakup dates and freeze-up dates are highly variable but the ice-free period was not any longer in 2015 than it was in 2004. However, this fall freeze-up is shaping up to be the earliest in decades.
  13. Problem bears in Churchill are not lean or starving.
  14. Churchill Manitoba had the most problem bears in 1983 and 2016, which were late freeze-up years, but many of the incidents in 2016 can be attributed to increased vigilance on the part of patrol officers after an attack in 2013.
  15. There have been only marginal sea ice declines during the feeding period in spring, when polar bears need sea ice the most.
  16. The is no evidence that subsistence hunting is affecting bear populations.
  17. Stressful research methods have been curtailed in much of Canada.
  18. There have been no reports of polar bear cannibalism since 2011.
  19. Polar bears appear unaffected by pollution: studies suggest only that harm is theoretically possible, not that it has happened.
  20. Polar bears have survived past warm periods, which is evidence they have the ability to survive future warm periods.


  • Polar bears are thriving: they are not currently threatened with extinction.
  • Tens of thousands of polar bears did not die as a result of more than a decade of low summer sea ice, as was predicted.
  • Polar bears don’t need sea ice in late summer/early fall as long as they are well-fed in the spring.

[full text below, pdf with footnotes and references here]

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