Tag Archives: Stirling

Scientific study finds polar bears excel at diving, contradicting previous expert opinion

A recent study by Norwegian biologist Karen Lone and colleagues, who tagged 57 polar bear females with sensors around Svalbard, discovered that polar bears can dive to a maximum depth of 13.9m and can swim long distances across open water without rest. Contrary to previous claims, polar bears are excellent divers and their breath-holding ability did not seem to limit how deep they could dive.

chukchi-bear-swimming-june-15-2014-brian-battaile-dsc_4036_lg.jpg

From the abstract of the new paper by Lone and colleagues (Lone et al. 2018):

“Some bears undertook notable long-distance-swims. Dive depths up to 13.9 m were recorded, with dives ≥5 m being common. The considerable swimming and diving capacities of polar bears might provide them with tools to exploit aquatic environments previously not utilized.”

Compare the above statement to one made by Stirling and van Meurs (2015), after describing a 3 minute dive video-taped during an aquatic stalk of a bearded seal, also in the Svalbard area:

“…increased diving ability cannot evolve rapidly enough to compensate for the increasing difficulty of hunting seals because of the rapidly declining availability of sea ice during the open-water period resulting from climate warming.” [my bold]

These two papers really show the difference between using anecdotal accounts as if they were evidence of species-wide physical abilities and doing a scientific study on the physical ability of interest.

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Hansen’s 1988 climate change testimony was the answer to Stirling’s polar bear problem

Last week’s media coverage made me realize that James Hansen’s testimony to a US Senate committee in 1988 provided well-timed answer to a vexatious problem facing polar bear biologist Ian Stirling. Thirty years ago, Stirling was struggling to understand why polar bear productivity in Western Hudson Bay had dropped.  He was ripe for the suggestion from Hansen (and his follow-up paper) that human-caused global warming could be the explanation. An interview with Stirling and colleague Andrew Derocher published in 2016 helps connect the dots.DA-IS-measuring_Ian Stirling

Many bears were in poor condition in the fall of 1983 (Calvert et al. 1986:19, 24; Ramsay and Stirling 1988). In general, the 1980s saw weights of bears decline and cub mortality increase, with a marked increase in the loss of whole litters over what had been documented in the 1960s and 1970s (Derocher and Stirling 1992, 1995).

Until Hansen and climate change came along,  density-dependent effects (such as the number of bears out-pacing food supply) were seen as the most likely explanation. But sea ice decline blamed on human-caused global warming was suddenly a new possibility that Stirling soon embraced (Stirling and Derocher 1993). By the late 1990s, sea ice coverage on Hudson Bay had indeed declined but the correlation with polar bear productivity produced a weak trend that was not statistically significant (Stirling et al. 1999).

The 1999 Stirling paper did not provide scientific evidence to explain the 1980s decline in productivity as much as it presented a novel scapegoat to blame when a more plausible explanation could not be made.

Bottom line: Global warming could not have been the proximate cause of the productivity changes in WH polar bears documented during the 1980s but Stirling spent the next two and a half decades vigorously pushing climate change as the cause of all polar bear ills. Continue reading

Critical evidence on W Hudson Bay polar bears still not published after 25 years

Polar bear researchers have been doing capture/recapture studies in Western Hudson Bay for decades yet most of the data claimed to be critical for assessing effects of human-caused global warming on this species have not been published. I raised this point in one of my early blog posts (27 Sept 2012) but the situation has not changed in 6 years. Here’s an update.

Derocher in the field in WH_CBC story 2016

From CBC story 14 Sept 2016.

Years ago now, in an oft-cited paper, Stirling and Derocher (2012) claimed to summarize the evidence that climate warming was negatively impacting polar bear health and survival. Several life history parameters were considered crucial, particularly body condition.

Despite almost a dozen papers (and perhaps more) on various aspects of WH polar bear health and life history studies based on capture/recapture data published since 2004  (e.g. Castro de la Guardia 2017; Lunn et al. 2016; Pilfold et al. 2017), none have reported the body condition data that supposedly support the claim that sea ice loss is having a severe impact — and the same is true for litter size, proportion of independent yearlings, and cub survival.1

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Harvey et al. paper becomes the poster child of the reproducibility crisis in science

Josh’s ‘stupidest paper ever’ cartoon is a reminder of the depths to which some people will descend to silence the voices of rational scientific debate just as the authors of the 2018 Harvey et al. BioScience paper qualifies it for the honour of poster child of the reproducibility crisis in science.

Poster Child of the reproducibilty crisis in science

By insisting — repeatedly and as recently as this month — that the information they released as supplementary data (find it here) was all that was used to construct the two figures in the paper (see Rajan and Tol 2018), the authors tacitly admit:

1) the data used to construct the figures were not derived from the methods they said they used

2) the work is not replicable

In other words, it is not science. That surely qualifies the Harvey et al. (2018) paper for the honour of poster child of the reproducibility crisis in science, discussed here and here (Baker 2016; Nosek et al. 2015). It’s an example the public will readily grasp, since the data said to have been used are easily accessible (and understood) by anyone who uses the Internet.

Below is the letter outlining the data release issue sent more than a week ago (18 May 2018) by Dr. Richard Tol, University of Sussex, to the president of the university highest academic authority in the Netherlands, where Jeff Harvey, lead author of the Harvey et al. 2018 BioScience paper, is employed as an academic [h/t R. Tol for the correction]. While Koninklijke Nederlandse Akademie van Wetenschappen [KNAW] in Amsterdam has a clearly stated data sharing policy, it is clearly not being upheld for the Harvey et al. paper — which nullifies the point of having a policy at all.

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Climate mauling, polar bears, and the self-inflicted wounds of the self-righteous

The BioScience paper “Internet blogs, polar bears, and climate-change denial by proxy” (Harvey et al. 2018) is a smack-talk response to my pointing out that polar bear numbers did not plummet as predicted when mid-century-like sea ice conditions arrived unexpectedly in 2007 (Crockford 2017). Here is why this shoddy piece of work will go down in history as a self-inflicted wound for the polar bear community (and biologist co-authors Ian Stirling and Steven Amstrup) and an own-goal for their wanna-be climate-hero friends, Stephan Lewandowsky, Jeff Harvey, and Michael Mann.

idea 1 final…absolutely the stupidest paper I have ever seen published” tweeted climate scientist Judith Curry, Emeritus Professor of Earth and Atmospheric Sciences at Georgia Institute of Technology (“Georgia Tech”).

Dr. Curry is a favourite target of colleague Michael Mann’s penchant for derogatory name-calling. Ironically, Mann often promotes something he calls the “Serengeti Strategy,” which he described to US Congress in 2017 in presenting himself as a victim of abused by others [my bold]:

“I coined the term “Serengeti Strategy” back in 2012 in “The Hockey Stick and the Climate Wars” to describe how industry special interests who feel threatened by scientific findings—be it tobacco and lung cancer, or fossil fuel burning and climate change—single out individual scientists to attack in much the same way lions of the Serengeti single out an individual zebra from the herd. In numbers there is strength, but individuals are far more vulnerable. Science critics will therefore often select a single scientist to ridicule, hector, and intimidate. The presumed purpose is to set an example for other scientists who might consider sticking their neck out by participating in the public discourse over certain matters of policy-relevant science.” Michael Mann, 2017 Congressional testimony.

Mann thinks others are using this strategy against him but if he had half an ounce of self-awareness he’d see it’s exactly what he and his long list of colleagues are doing with the Harvey et al. BioScience attack on me. Intimidation by numbers is the only rational explanation for a roster of 14 when two incompetent researchers could have produced a similar result.

Polar bear specialists Ian Stirling and Steven Amstrup knew they didn’t have a valid argument to refute my paper (Crockford 2017; Crockford and Geist 2018) on their failed polar bear survival model (Amstrup et al. 2007), which their responses to my International Polar Bear Day (27 February 2018) Financial Post op-ed revealed to the world (see here and here with references).

So when ignoring me didn’t work – or, more accurately, when the world started paying too much attention to me, by their own admission (Harvey et al. 2018:3) – they teamed up with Michael Mann, Jeff Harvey, and Stephan Lewandowsky (all with previous form attacking colleagues who don’t share their views) to publish an academic paper attacking my scientific integrity. In the words of Terence Corcoran, I was “climate mauled.”

Judith Curry stated recently (14 February 2018), regarding the Mann lawsuit against Rand Simberg, Mark Steyn and the National Review vs. the attacks on her integrity:

“Mann’s libelous statements about me (because he is a scientist with many awards) are far more serious than say Rand Simberg’s statements about Mann.”

In other words, like the attack on me in the Harvey paper (used to libel other internet bloggers by association), when senior scientists like Mann, Stirling, and Amstrup use derogatory and defamatory language against a colleague it’s a serious breach of professional ethics that impacts careers. Harvey et al.’s attack against me may be worse than those against Curry at a Congressional Hearing because it has been entered into the scientific literature in my own field.1

However, I expect BioScience (read mostly by teachers, students, and the general public, and therefore widely subscribed to by public libraries) was the only outlet willing to publish such unprofessional tripe. The editor’s refusal to retract the paper after numerous complaints about the language and the quality of the scientific content, tells you all you need to know about the journal’s low, sectarian standards. For example, the notice showing the two corrections they were willing to make at the end of March 2018 had to be pulled because such an egregious error occurred (it was posted to the wrong journal) it got the attention of online watchdog Retraction Watch! [Still not fixed as of 8 April]

Polar bear paper correction retraction_5 April 2018

It also tells us quite a lot about the bias of its publishers, the American Institute of Biological Sciences.

Did you know, for example, that this organization has an “actionbioscience” program that provides free idealogically biased content aimed at kids and teachers that’s not particularly different from the biased content produced (without references) for kids and teachers by activist conservation outfit Polar Bears International (employer of Harvey et al. co-author Steve Amstrup)? The AIBS actionbioscience program currently includes an out-of date, alarmist essay by litigious Center for Biological Diversity employee Shaye Wolf on the plight of penguins (from 2009) as well as one by pessimistic polar bear specialist Andrew Derocher (from 2008) .

If you are able, please support the work I do here at PolarBearScience, some of which will go to Josh for these fabulous cartoons:

Here is a list of issues regarding the Harvey et al. paper as well as responses to it: some of these you won’t have heard before. Because this is a long summary post, for convenience I offer it here also in pdf form (latest version with a few typos/spelling errors corrected): Climate mauling, polar bears, and self-inflicted wounds of the self-righteous.”

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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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Archive of 2007 USGS reports supporting 2008 ESA listing for the polar bear

The administrative reports used in 2007 to support the decision to list polar bears as ‘threatened’ under the US Endangered Species Act (ESA) in 2008 disappeared from the US Geological Survey website several years ago. I have archived them here in pdf format to make them easy to find for anyone wishing to access the accuracy of the models, data, and assumptions made in 2007.

Amstrup w triplet_Prudhoe Bay 2005_USGS_sm

Steven Amstrup in 2005, then lead USGS polar bear biologist, with triplet cubs, Prudhoe Bay, AK.

This is a housekeeping post meant for future reference. I’ve included citations for the relevant sea ice projection papers used in the models presented in the 2007 documents and a few other related reports from the same time period. Continue reading

Two technical critiques of the Harvey et al. polar bear Bioscience attack paper

Not much time for blogging, but two technical critiques  of the Harvey et al. paper have recently been posted, which you might like to read at your leisure. I will update this post when I can if more critiques appear plus I’ve provided a list of previous posts (my and others) on this issue.

Polar Bears, Inadequate data and Statistical Lipstick (18 Decemeber 2018, RomanM writing at ClimateAudit)

McIntyre guest blog on Harvey paper photo led_RomanM 18 Dec 2017

Polar bear attack paper invalidated by non-independent analysis” (Cross posted 14 December 2017 at ClimateScepticism from the blog of Shub Nuggarath, 12 December 2017).

UPDATE 19 December 2017: Richard Tol has posted a draft of his critique, which was itself updated 20 December “Lipstick on a bear” in which he concludes:

“In sum, Harvey et al. (2017) play a statistical game of smoke and mirrors. They validate their data, collected by an unclear process, by comparing it to data of unknown provenance. They artificially inflate the dimensionality of their data only to reduce that dimensionality using a principal component analysis. They pretend their results are two dimensional where there is only one dimension. They suggest that there are many nuanced positions where there are only a few stark ones – at least, in their data. On a topic as complex as this, there are of course many nuanced positions; the jitter applied conceals the poor quality of Harvey’s data. They show that these is disagreement on the vulnerability of polar bears to climate change, but offer no new evidence who is right or wrong – apart from a fallacious argument from authority, with a “majority view” taken from an unrepresentative sample. Once the substandard statistical application to poor data is removed, what remains is a not-so-veiled attempt at a colleague’s reputation.”

UPDATED 20 December 2017: Lead author of the Bioscience attack paper Jeff Harvey talked to an Amsterdam newspaper about the backlash to the paper, original Dutch and English translation here.

Fig 3 Sea ice prediction vs reality 2012

Predicted sea ice changes (based on 2004 data) at 2020, 2050, and 2080 that were used in 2007 to predict a 66% decline in global polar bear numbers vs. an example of the sea ice extent reality experienced since 2007 (shown is 2012). See Crockford 2017 for details.

Read a short summary of the paper that Harvey et al. don’t want you to know about here:

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

The paper they don’t want you to read is 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

The paper being criticized (Harvey et al. 2017, in press: “Internet blogs, polar bears, and climate-change denial by proxy”, Bioscience, open access) is available here.  There is a supplementary data file available here and the data for the principal component analysis is available here  and (h/t to R. Tol), the R code is available here

More on this after Christmas but for now a list of previous blog posts of mine and others is provided below. Continue reading

Polar bears refused to die as predicted and this is how the propheseers respond

The polar bear experts who predicted tens of thousands of polar bears would be dead by now (given the ice conditions since 2007) have found my well-documented criticisms of their failed prophesies have caused them to lose face and credibility with the public.

Fig 3 Sea ice prediction vs reality 2012

Predicted sea ice changes (based on 2004 data) at 2020, 2050, and 2080 that were used in 2007 to predict a 67% decline in global polar bear numbers vs. an example of the sea ice extent reality experienced since 2007 (shown is 2012). See Crockford 2017 for details.

Although the gullible media still pretends to believe the doomsday stories offered by these researchers, the polar bear has fallen as a useful icon for those trying to sell a looming global warming catastrophe to the public.

Here’s what happened: I published my professional criticisms on the failed predictions of the polar bear conservation community in a professional online scientific preprint journal to which any colleague can make a comment, write a review, or ask a question (Crockford 2017). Since its publication in February 2017, not one of the people whose work is referred to in my paper bothered to counter my arguments or write a review.

They ignored me, perhaps hoping the veracity of my arguments would not have to be addressed. But it has not turned out that way. Now, too late, they have chosen a personal attack in the journal BioScience (Harvey et al. 2018 in press).

UPDATE 30 November 2017: See a detailed criticism of this nasty paper here and a shorter one below.

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Why is polar bear conservation such a contentious issue?

Are polar bears in decline or not? Who is to blame for the fact that there is no clear answer about how polar bears are doing? Apparently, everyone except polar bear specialists are at fault for the way polar bear issues have been handled in recent years (including me), at least according to one northern journalist.

UpHere Magazine_July 2016 cover cropped

Back in February, I wrote a rather critical review of an exclusive interview with polar bear researcher Ian Stirling that was published in the February issue of UpHere Magazine called, He speaks for the polar bears – with this lede under the title:

“No fear-mongering. No exaggeration. For Ian Stirling, it’s purely about the science.”

I said “Yeah, well – judge for yourself,” and pointed out some rather critical inaccuracies and obfuscations in Stirling’s answers that I backed up with references.

Well, the editor of that magazine, Tim Edwards, emailed me a few days later and said:

“...we wanted to try to clarify the issues and just talk hard science, no rhetoric. Lo and behold, we’re learning that even his opinion is by no means universally agreed-upon. So thank you for your criticism.”

In May, I was contacted by UpHere writer Dan Campbell, who spoke to me several times before writing this month’s article (15 July 2016), Lost in the numbers: The polar bear is getting more attention than ever, but that may be harming the animal more than helping. Have a look and decide if it clarifies any of the polar bear issues for you. Continue reading