Tag Archives: USGS

USGS ‘treadmill’ paper repeats bogus claim that ice loss harmed polar bears

The newest polar bear science paper making the rounds courtesy the US Geological Survey, is a perfect example of a statistically-significant result with no biological significance. While the results are rather lame, the paper is dangerous because it repeats the disingenuous claim (see Crockford 2017) that Southern Beaufort Sea polar bear numbers declined in recent years due to summer sea ice loss.

polar_bear_rubble_ice_Mike Lockhart USGS_8 April 2011

The USGS authors (Durner et al. 2017) know this harm-from-summer-ice-loss assertion is not true for the Southern Beaufort subpopulation but the more papers they can get into print that say so, the more likely it will be believed — and the less likely readers will check older literature that documents the recent decline in polar bear numbers was due to a three year period (2004-2006) when thick ice conditions in spring made seal hunting a challenge, a repeat of a well-known phenomenon (e.g. Stirling et al. 1980; Stirling 2002) unique to this region that has been documented since the 1960s.

The Durner paper (USGS press releaseIncreased Sea Ice Drift Puts Polar Bears on Faster Moving Treadmill” published online 6 June ahead of print) spins the research results as potentially significant bad news but in so doing reveals how desperate they have become to make the public and their biology colleagues believe that Southern Beaufort polar bears, among others, are being negatively affected by summer sea ice loss (as per Stirling and Derocher 2012).

Durner, G.M., Douglas, D.C., Albeke, S.E., Whiteman, J.P., Amstrup, S.C., Richardson, E., Wilson, R.R. and Ben-David, M. 2017. Increased Arctic sea ice drift alters adult female polar bear movements and energetics. Global Change Biology. DOI: 10.1111/gcb.13746 http://onlinelibrary.wiley.com/doi/10.1111/gcb.13746/abstract [paywalled]

In fact, the Durner et al. paper does not document any harm to polar bears from the proposed ‘treadmill’ effect of more rapidly moving ice for the period 1999-2013 compared to 1987-1998, but instead uses models to suggest bears might have to eat one to three more seals per year to compensate for the extra energy needed to walk against the moving ice. That’s right: perhaps only 1 more seal per year out of the 50 or so they would usually consume (see Stirling and Øritsland 1995). In my opinion, that’s a pretty lame result for what one of the co-authors described as an immense amount of work.

News outlets have essentially used the USGS press release as a click-bait lede for another round of Trump-bashing with respect to the Paris climate change agreement, see here and here: the stories are hardly about polar bears at all. And predictably, polar bear activist and co-author Steven Amstrup (paid spokesperson for Polar Bears International, famous for their “Save Our Sea Ice” campaign) appears to be using the same approach: an up-coming call-in talk radio program at NPR’s Anchorage affiliate KSKA for Tuesday 13 June at 10:00 (Alaska time, see “Talk of Alaska”) is being billed as a discussion of “polar bears, climate change, and the Paris Accord” (h/t AK geologist). Continue reading

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.

This may not be a statistically significant increase but it is also not the catastrophic decline that was predicted to occur in association with the abrupt drop of summer sea ice in 2007 to a new average of about 3-5 mkm2 [updated 1 June 2017].

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.


[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).

Continue reading

As polar bear populations fail to decline with sea ice, message of doom intensifies

If 10 years of summer sea ice levels expected to kill 2/3 of the world’s polar bears by 2050 hasn’t had an impact, why would anyone expect a bit less summer ice will do the job?


The more the polar bears fail to die in droves, the shriller the message from activist polar bear researchers – via willing media megaphones – that the great death of the bears will soon be upon us, just you wait and see!

Some big media guns were out this past week spreading the prophesy of doom fed to them by the polar bear researchers most committed to the “threatened with extinction” narrative: The New York Times, The Atlantic, The Guardian. The desperation is becoming palpable as the public catches on to their epic failure.

In 2007, the sea ice dropped to a level the experts said wouldn’t be reached until mid-century, and since then, it has remained at that low level (about 3-5mkm2, give or take some measuring error). And in 2007, US Geological Survey (USGS) biologists said with absolute confidence that when sea ice levels reached that point, 2/3 of the world’s polar bears would be gone.

No bears at all would remain, they said, in Western Hudson Bay (the Churchill bears), Southern Hudson Bay, Foxe Basin, Davis Strait, Baffin Bay, Southern Beaufort, Chukchi Sea, Barents Sea, Kara Sea, and the Laptev Sea:  ten out of 19 subpopulations would be extirpated if sea ice levels in most years dropped to the summer lows in the 3-5 mkm2 range.

On the basis of that prediction, polar bears were declared ‘threatened’ with extinction by the US Fish & Wildlife Service (USFWS) under the Endangered Species Act (ESA).

But nothing of the kind happened. There are still lots of polar bears – and not even struggling-to-survive bears but lots of fat healthy bears everywhere across the Arctic, in what were considered by USGS biologists to be the most vulnerable regions of all: Western Hudson Bay (i.e., Churchill), Chukchi Sea and Southern Beaufort (Alaska) and the Barents Sea (Norway).

This is the truth the world needs to hear: the experts were wrong. Polar bears have not been driven to the brink of extinction by climate change, they are thriving. This is the message of each of my two new books (one of which is appropriate for kids of all ages, see the sidebar).

In turns out that polar bears are much more resilient to changing levels of sea ice than data collectors assume and the proof is in the current healthy populations everywhere. Continue reading

Polar bears that didn’t die from recent sea ice loss will die in 35 yrs, say ‘sperts

Yesterday, the DailyMail (among others) was suckered into running virtually the same story The Guardian (among others) hyped last year about this time.

Using a science journal version of the 2015 IUCN Red List assessment report, polar bear data collectors and their fortune-teller colleagues have managed to get polar bears back in the news.


I wrote about this last year – it’s actually good news, although you wouldn’t know it from the headlines.

Let me paraphrase the ‘sperts:

“After 10 years of ice conditions we didn’t expect would happen until mid-century (a worst-case scenario we said would cause more than 30% of the world’s polar bears to die – except they didn’t), we have now determined (using a new model and a brand new definition of sea ice specific to polar bears) that by mid-century, there is only a 70% chance that 30% of polar bears will die.”

This is how they explain away all the bears that didn’t die as they should have when summer sea ice declined to about 5 mkm2 and below after 2006.

Continue reading

BBC Arctic Live for viewers outside the UK: watch scientist distort polar bear facts

Viewers outside the UK can now watch polar bear scientist Steve Amstrup live (Episode 2, filmed 2 November 2016), state that there are “20,000-25,000” polar bears in the world, almost a full year after the IUCN Red List put the worldwide polar bear population size at 22,000-31,000.

[even though Amstrup (now chief scientist and spokesperson for Polar Bears International) was a co-author of that 2015 Red List report, Wiig et. al. 2015]


Watch Steve Amstrup, live (Episode 2, filmed 2 November 2016) state that sea ice is only “usually” present in March/April when females with cubs emerge from their dens to feed – as if there has ever not been sea ice present at this critical time of year!

Watch Amstrup , live (Episode 2, filmed 2 November 2016) not point out that the prediction he was responsible for making in 2007 (that got polar bears listed as ‘threatened’ in the USA) has been a total failure: even though the USGS models predicted that polar bear numbers worldwide would decline by 67% and Western Hudson Bay polar bears (as well as nine others) would be wiped out completely when summer sea ice reached the levels they’ve been at since 2007, he pretends that prediction was scientifically valid.

We’ve had sea ice levels not predicted to occur until 2050 for 8 out of the last 10 years and polar bears are still going strong. If Amstrup had been right about the relationship of summer sea ice and polar bear numbers, there would have been no polar bears in Churchill for the BBC to film this year.

Watch all three hour-long episodes below as these two organization team up to promote fear of future global warming with polar bears (or polar bears, as Humble says it). Decide for yourself if polar bear science is being fairly represented.
Continue reading

Tracking west Alaskan polar bears in the Beaufort in October – all at Banks Is., CAN


Two out of three polar bear females that were collared by USGS researchers near Barrow, Alaska last spring are hanging out on the northwest coast of Banks Island, Canada. The other bear (bright green icon) appears to have been collared on the ice off Prudoe Bay in April. And as I discussed last month, it’s unusual for bears from the western end of the Southern Beaufort subpopulation (or even the central region) to end up in the Northern Beaufort subpopulation territory.


Original caption: “Movements of 3 satellite-tagged polar bears for the month of October, 2016. Polar bears were tagged in 2016 on the spring-time sea ice of the southern Beaufort Sea. All 3 of these bears have satellite collar transmitters. Polar bear satellite telemetry data are shown with AMSR2 remotely-sensed ice coverage from 29 October, 2016.” See full resolution image here and close-up below.

Continue reading