Tag Archives: polarbearscience

USGS promotes another flawed polar bear model: GHG emissions still “primary threat”

It’s still based on the same flawed ecological premise as all previous models – it assumes that sea ice was a naturally stable habitat until human-caused global warming came along. It also uses slight-of-hand maneuvers to correlate declining summer sea ice and declining polar bear population numbers.


Just because they keep repeating the same hype doesn’t make it true.
Continue reading

Polar bear news: 1st fat bear ashore in WHB, trouble in S. Greenland, and more hybrid hype

Last week, among other events, the first fat polar bear of the season was photographed on shore in Western Hudson Bay, a fat bear was run out of town in South Greenland, and media outlets spread misinformation – apparently preferring global warming hype to rational facts.

1) First polar bears have been seen onshore in Western Hudson Bay in Wapusk National Park near Cape Churchill (map below) on 18 June this year, apparently fat and well prepared for the summer fast. My informants tell me a few bears usually come ashore in June near Churchill before ice conditions make this necessary; the bulk of the population will probably continue seal hunting for a few more weeks. Those bears will come ashore along the southwest coast (near Polar Bear Provincial Park, in Ontario, see Fig. 2 below). They’ll make their way north to the Churchill area in time for freeze-up in the fall. Watch one fat bear caught on camera on 18 June, below :

2) Fat polar bear spotted in Nanortalik, Southern Greenland 18 June 2015, a bit further south than usual. People from the community drove it away, but not before taking lots of pictures.

Greenland South_polar-bear-nanortalik-08_henrik-hansen_June_18_2015

Some very cool photos, including the one above (taken by Henrik Hansen), worth a look. This bear was in excellent condition, well prepared for the summer fast ahead, whether he ends up spending it on shore somewhere (but not near this community!) or on the sea ice further north in SE Greenland (Fig. 1 below). The ice in that areas is probably broken up (~15-30% concentration) but this is enough for the bear to swim from flow to flow to make it’s way up the northeast coast where most East Greenland bears spend the summer.
Continue reading

Same amount of sea ice for Hudson Bay polar bears as 2013, bears still on the ice

Sea ice coverage for Hudson Bay on 14 June converged on levels recorded in 2013, when breakup was slightly later than the average of the last two decades.


There is also more ice over Hudson Bay than there was in 2011, which was an early breakup year (charts for other Arctic regions here, originals here).

Andrew Derocher notes (via twitter) that rather than heading to shore, most of the Hudson Bay bears with satellite tracking collars (7/10) are out on the ice (Fig. 1 below). They appear to be hunting along the ice edge, where they are most likely to find seals.

Update 17 June 2015: Sea ice images for the week 18 June 2015 compared to other years added below, for Hudson Bay and the Beaufort Sea.

Continue reading

Polar bear behaviour gets the animal tragedy porn treatment – two new papers

Recently, several polar bear biologists have teamed up with photographers to get pictures of starving bears into the scientific literature – and picked up by the media, with mixed results.

For the second time in five years, polar bear biologist Ian Stirling has teamed up with a photographer to give unwarranted scientific credence to an anecdotal account of polar bear behaviour. It included a picture of a pitifully thin animal  (classic animal tragedy porn) and was framed to increase alarm over predicted effects of global warming. It got little media attention.

His Norwegian colleagues Jon Aars and Magnus Andersen have just done the same with a bear caught eating a white-beaked dolphin (photo above) – but this time the media took the bait.

Update 13 June 2015 – Information added on white-beaked dolphin distribution, sea ice conditions in 2014 and a correction. See below.
Continue reading

My new Arctic Fallacy paper- Sea ice stability and the polar bear

I have a new paper out that explains a fundamental problem with polar bear conservation.

Chukchi June 15 2014_USGS_Brian Battaile_after swim_sm

I’m convinced that a flawed and out-dated ecological concept — that sea ice, under natural conditions, provides a stable, predictable habitat — is what has allowed the present doom and gloom attitude of most polar bear specialists to develop.

Sea ice changes, of course, from season to season. However, the concept that sea ice is a stable habitat assumes that these seasonal changes are predictable and virtually the same from one year to the next – at least, similar enough that the differences are not responsible for causing marked declines in population size.

The assumption is that under natural, stable conditions populations of Arctic animals will either stay the same over time or increase. Biologists were taught at university that sea ice should be a stable habitat and as a result, they’ve glossed over evidence they collected to the contrary. [see recent posts here and here, for example]

Negative effects on populations of short-term natural variations in spring sea ice or spring snow cover on sea ice have been entirely ignored in modeled predictions of future conditions. The focus has been on summer ice extent.

I have summarized this evidence in a fully referenced, peer-reviewed essay that explores how the acceptance of this fallacy (“sea ice is a stable habitat”) has so skewed the conservation biology of polar bears that to outsiders it may look like a scientific integrity issue.

The summary and the essay are below (with embedded links and references). The Global Warming Policy Foundation (GWPF) has published the essay in their “Briefing Paper” series (#16, The Arctic Fallacy: Sea Ice Stability and the Polar Bear), which includes a must-read foreword by Dr. Matthew Cronin, Professor of Animal Genetics at the University of Alaska Fairbanks. Press release here, pdf here.

I think you’ll find it timely and thought-provoking.

Continue reading

Hudson Bay breakup date for 2015 will really depend on which definition you use

Is breakup imminent for Hudson Bay sea ice? Probably not, but this year more than ever, it will depend on how you define it. Hudson Bay concentratation_2015 June 1_CIS Despite a large patch of open water in western Hudson Bay (CIS chart above, for 1 June), there is still more than 70% sea ice coverage over the entire bay as of this week, when you use the standard breakup definition of 50% ice coverage (Fig. 1).  Ice remaining over the bay is mostly 90% or greater, as the chart above shows – which means there is still a lot of polar bear hunting habitat remaining.

Figure 1.

Figure 1. Sea ice coverage over Hudson Bay, as a percentage, for the week of 4 June, 1971-2015. Click to enlarge.

The interconnected region of Hudson Bay, Hudson Strait, and southern Davis Strait (Fig. 2), what the Canadian Ice Service calls “Regional Hudson Bay,” is only slightly below average for the week of 4 June.

Regional Hudson Bay, week of 4 June.

Figure 2. Regional Hudson Bay, week of 4 June. Click to enlarge.

Since ice concentration is factored into breakup date calculation, a record-early breakup is simply not possible, since the previous record date (2 June, for 1990) has already passed. It might be an earlier than average breakup year but not very early, based on the 50% coverage definition (Fig. 3, below). This year, because of the unusual pattern of breakup of Hudson Bay ice, it will be critical for polar bears which definition of breakup is used – the old, 50% method (adopted because it’s what sea ice professionals used) or the newest one, which was determined to be most relevant to WHB polar bears (Cherry et al. 2013).

UPDATE 6 June 2015: I’ve added the forecast for ice conditions over the summer for North America (which for these folks includes June because it’s aimed at temperate NA, polar bear folks call June the end of spring), provided by the Canadian Ice Service: “Seasonal outlook for North American Arctic Waters issued by the North American Ice Service on 2 June 2015” [points of potential interest marked] The sea ice forecast (Table 1) for southwestern Hudson Bay (where most western and southern Hudson Bay polar bears come ashore) is for complete ice melt by 1 Aug, eight days later than the earliest date over the period 1968-2013. Time will tell if that’s what happens.
Continue reading

Global polar bear population size is about 26,000 (20,000-32,000), despite PBSG waffling

The IUCN Polar Bear Specialist Group admits its global population estimate is simply a qualified guess with a large potential error.  So perhaps it’s time to acknowledge that for the purpose of comparing polar bears to other species of concern, the upper limit for polar bear numbers worldwide could be more than 30,000?

Polar bears USFWS_cover PolarBearNews2013_2014

See previous posts on this global population size issue (here and here); updated information below, including the most recent IUCN PBSG statement.

UPDATE 1 September 2015: here is an updated graph of polar bear population numbers that undo the “subtractions” of the PBSG between 2001 & 2013, giving a final global estimate of about 26,000. Click to enlarge:

Crockford unofficial polar bear numbers to 2015 Sept 1 FINAL

UPDATE 25 November 2015: The 2015 update of the IUCN Red List for polar bears essentially concurs with my assessment about polar bear numbers. They estimate the current global population is 20,000-31,000 (average of 25,500, see below, without considering the number of bears in the Arctic Basin, so not far off my assessment) but say the trend in the population is “Unknown.”

Crockford OFFICIAL polar bear numbers to 2015_IUCN concurrs Nov 18

UPDATE 23 February 2017: A new population estimate update is available based on three new survey counts that add about 2,000 bears to the average total, bringing it to almost 30,000 (28,500). Details here.

Continue reading