Tag Archives: Regehr

Chukchi Sea polar bears number almost 3000 according to new survey results

The Chukchi Sea finally has a polar bear population estimate! According to survey results from 2016 only recently made public, about 2937 bears (1522-5944) currently inhabit the region, making this the largest subpopulation in the Arctic. This is exciting news — and a huge accomplishment — but the US Fish and Wildlife Service responsible for the work has been oddly mum on the topic.

beaufort-bears_-suzanne-miller-usfws-3-af-2c-on-spit-1.jpg

Not only that, but an extrapolation of that estimate calculated by USFWS researchers for Chukchi plus Alaska (the US portion of the Southern Beaufort Sea subpopulation) was estimated at 4437 (2283-9527), although with “significant uncertainty.” Nevertheless, it means the 2016 estimate for Alaska could be roughly three times what it was in 2010: a whopping 1500 or so, up from about 450 (or about 225-650) for the same area estimated during the last survey (Bromaghin et al. 2015: Fig. 5a).

Even if the real number for Alaska is only twice as large (~1000), that’s still a huge improvement. It would eliminate the Southern Beaufort as the only polar bear subpopulation in the Arctic to have shown a significant decline blamed on human-caused global warming (Crockford 2018). If the recovery is real, it means the 2004-2006 decline was a temporary fluctuation after all, just like previous declines in the region. I expect, however, that it will take a dedicated SB population survey for officials to concede that point.

There is not yet a detailed report to cite (Regehr et al. in prep), but the numbers were announced at the 10th meeting of the Russian-American Commission on Polar Bears held at the end of July this year (AC SWG 2018) by Eric Regehr (formerly of the US Fish & Wildlife Service, as of 2017 at the University of Washington). [h/t to G.H.] This was the same report that raised the quota for subsistence hunting in the Chukchi from 58 to 85, based on these new figures, as I discussed last week.

Wrangel Island polar bear with cubs 2015 news story

From “Military bases to open on Wrangel Island and Chukotka” 22 October 2015.

Regehr was quoted as saying:

“Chukchi bears remain larger and fatter and have not seen downward trends in cub production and survival, according to new preliminary information on the health and numbers of bears.”

Continue reading

Facts contradict predictions that Chukchi Sea polar bears should be in trouble

Last fall, there were persistent alarms raised about low levels of sea ice in the Chukchi Sea that were echoed this spring. But these low ice levels are not really a serious concern for these polar bears: a 2018 assessment found the bears were in excellent health with no declines in cub production or survival. Funny how little we hear about that.

Wrangel Island polar bear with cubs 2015 news story

From “Military bases to open on Wrangel Island and Chukotka” 22 October 2015.

See a photo essay of Wrangel Island here and of the islands polar bears here and here.

You also don’t hear about the fact that sea ice has declined by about the same amount in the Chukchi Sea as in Western Hudson Bay. Since 1979, sea ice in the Chukchi Sea has declined at a rate similar to Western Hudson Bay (-0.90 days per year vs. -0.86 days per year, respectively), see graphs below from Regehr et al. (2016, Fig. 2):

Regher et al. 2016 fig 2 Barents and Chukchi Sea ice declineRegher et al. 2016 fig 2 Wh Bay ice decline

While Western Hudson Bay bear numbers have declined slightly in number (by a non-statistically significant amount) and appear to have suffered some recent declines in cub survival (Dyck et al. 2017) (with unsubstantiated claims of declines in adult body condition), Chukchi Sea bears have not (Rode and Regehr 2010; Rode et al. 2013, 2014, 2018).

The fact that Chukchi bears are thriving while Western Hudson Bay bears appear to be struggling, given almost identical trends in sea ice decline, is a connundrum that polar bear specialist are loath to explain.

Only last week, it was announced that the quota for subsistence hunting of Chukchi Sea polar bears had been raised from 58 to 85 due to the excellent status of the population. Polar bear biologist Eric Regehr was quoted as saying:

“Chukchi bears remain larger and fatter and have not seen downward trends in cub production and survival, according to new preliminary information on the health and numbers of bears.”

So, despite warnings from the polar bear and sea ice “experts” that Chukchi Sea bears may be in dire straits due to recent sea ice declines (see below), it appears that the bears themselves are more resilient to changing conditions than the experts give them credit.

NSIDC sea ice experts cruising the Chukchi Sea took this photo of a polar bear in excellent condition a couple of weeks ago (early August 2018, A. Khan), despite the scary-looking melt ponds:

Chukchi Sea polar bear Arctic_early August 2018_A Khan NSIDC

Continue reading

IUCN polar bear specialists reject IPCC- supported forecasts of sea ice based on CO2

In case you missed it — or missed the significance of it — polar bear specialist Mitch Taylor correctly pointed out in his recent essay (a response to the New York Times article that appeared Tuesday (10 April) about the Harvey et al. (2018) BioScience paper) that the IUCN Polar Bear Specialist Group have given up using computer models of future sea ice extent based on rising CO2 levels supported by the IPCC.

Polar_Bear_male_Regehr photo_March 21 2010_labeled

Their latest assessment (Regehr et al. 2016) does not link polar bear survival models to climate modeled forecasts of Arctic sea ice decline but rather to an assumption that declines already documented will continue in linear fashion over this century.

This means that CO2 emissions blamed on human fossil fuel use is no longer directly tied to the predicted future decline of polar bear numbers: IUCN polar bear specialists simply assume that sea ice will continue to decline in a linear fashion with no cause attributed to that decline except the broad assumption that anthropogenic climate change is to blame for Arctic sea ice declines since 1979.

No wonder former USGS polar bear biologist Steve Amstrup never refers to this IUCN PBSG study: he and the organization that now employs him, Polar Bears International, are still firmly wedded to the concept that CO2 is the sea ice control knob.

Continue reading

Polar bear specialist Mitch Taylor on accountability in polar bear science

Polar bear specialist Mitch Taylor emailed me and others his response to the New York Times article that appeared Tuesday (10 April) about the Harvey et al. (2018) BioScience paper attacking my scientific integrity. Here it is in full, with his permission, and my comments. Don’t miss the footnote!

Mother with cubs Russia_shutterstock_71694292_web size

Continue reading

US biologist’s defense of flawed polar bear predictions is an embarrassment to science

A few days ago in a radio interview, a senior US Fish & Wildlife biologist repeated the tall tale that Southern Beaufort Sea polar bear numbers declined in recent years due to loss of summer sea ice. But restating this egregious misinformation does not make it true.

polarbears-arcticnatlwildliferefuge-suzannemiller-usfws_labeled_sm

The Southern Beaufort population did decline between 2001 and 2006 but it was due to natural causes (thick ice in spring from 2004 to 2006) – it had nothing to do with recent summer sea ice loss and Eric Regehr knows it.

There is no evidence that the population decline continued after 2006, so it cannot be said to be still declining. Moreover, the situation in the Southern Beaufort does not support the predictions made by Regehr and his colleagues that polar bear populations will decline precipitously if summer sea ice declines further.

My recently published paper demolishes the message of doom for polar bears and the misinformation it’s based upon: it’s free and written in straight-forward scientific language.

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).

Here’s an excerpt of the nonsense broadcasted on KNOM Radio Alaska by Regehr and transcribed for their website (29 January 2017) [my bold]: 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.

crystalball_468x317_predictions_sq

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

New paper finds experts were wrong: polar bears are not “walking hibernators”

A polar bear paper just out in Science concludes the experts were wrong, polar bears are not “walking hibernators” – in summer, they slow down and live off their accumulated fat just like other mammals. Take home message: experts are not infallible and spring fat is critical for polar bear survival over the summer.

polarbears-arcticnatlwildliferefuge-suzannemiller-usfws_labeled_sm

This paper presents no compelling evidence that Southern Beaufort polar bears, or those in any other region, lack the ability to survive predicted summer sea ice declines in future decades – although they claim it does. See what you think.
Continue reading