Tag Archives: population estimate

Polar Bear Specialist Group population status update is much ado about nothing

Posted on February 1, 2014 | Comments Off

I cannot for the life of me fathom why the IUCN Polar Bear Specialist Group (PBSG) bothered to insert an announcement on their website back in mid-December, promising an updated polar bear status assessment, since the posted January 31 “update” is nothing of the sort — there have been no changes of any consequence.

It therefore appears I interpreted the oddly worded announcement incorrectly and none of the anticipated changes were forthcoming. Baffling, to say the least. Have a look at the new updated documents that were posted yesterday and see what you think.

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Posted in Conservation Status, Population

Tagged conservation, meeting of the parties, PBSG, polar bear, Polar Bear Specialist Group, population estimate, population status, status table, status update

Lancaster Sound – a rarely-mentioned region with a large polar bear population

Posted on October 27, 2013 | Comments Off

The polar bear subpopulation designated as Lancaster Sound lies at the eastern entrance to the Northwest Passage in the Canadian High Arctic (Fig.1). We rarely hear about it but this region has one of the largest polar bear populations anywhere in the Arctic – only the Barents Sea and Foxe Basin have higher estimated population sizes.

Figure 1. Lancaster Sound, magenta. Map courtesy Polar Bear Specialist Group, additional labels added.

Figure 1. Polar bear subpopulations with Lancaster Sound marked. Map courtesy IUCN Polar Bear Specialist Group, additional labels added.

Lancaster Sound includes the communities of Arctic Bay on northwestern Baffin Island and Resolute Bay on Cornwallis Island. Devon Island, which lies on the northern boundary, has no permanent communities, although two research stations are present (see here and here). A more detailed map showing the exact boundaries is available in Vongraven and Peacock (2011).

The eastern portion of Lancaster Sound is generally clear of ice by late summer (hence the Northwest Passage) but the western third of the region not only retains pack ice later in the season but some multiyear ice remains throughout the year.

The proximity of Lancaster Sound to Baffin Bay and the eastern Northwest Passage (Fig.2) undoubtedly exposed polar bears there to hunting by European whalers during the 1800s and early 1900s (see previous post here, especially Fig. 5), from which the population appears to have recovered.

On the other hand, the proximity of Lancaster Sound to oil and gas reserves further north in the High Arctic generated much-needed funds for polar bear biologists in the mid-to-late 1970s to collect essential baseline data for the entire region (Schweinsburg et al. 1982; Stirling et al. 1979, 1984; Stirling and Latour 1978).

Figure 2. The main Northwest Passage route starts at Lancaster Sound and runs east through Parry Channel because these waterways routinely clear of ice in late summer. The approximate boundary of the Lancaster Sound polar bear subpopulation is marked in yellow; POW is Prince of Wales Island. Map from Wikipedia, labels added. Click to enlarge.

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Posted in Conservation Status, Population, Sea ice habitat

Tagged Arctic Bay, baffin bay, Barents Sea, Chukchi Sea, Davis Strait, Devon Island, fossil fuels, Foxe Basin, funding from oil companies, Lancaster Sound, male-biased hunting, natural gas, Northwest Passage, over-harvest, PBSG, Polar Bear Specialist Group, population estimate, Resolute Bay, Rode, Schweinsburg, sea ice decline, Stirling, Taylor

Misleading “State of the Polar Bear” graphic still not fixed

Posted on April 1, 2013 | Comments Off

UPDATE FEBRUARY 19, 2014 – The misleading “State of the Polar Bear” graphic is now GONE (as of January 31, 2014). A new 2013 status table is offered by the PBSG here. It has detailed text explanations and harvest information, with references, hyperlinked to each subpopulation entry (“Press the subpopulation hyperlink and more information will appear“) and may have replaced the “State of the Polar Bear” graphic that the PBSG commissioned for upwards of US$50,000, although the PBSG website says it is being “updated” [A pdf copy of the 2013 colour table is here, and my commentary on it is here.] I have left the original post as is, below.

This is an update regarding the IUCN Polar Bear Specialist Group (PBSG)’s fancy, multilevel State of the Polar Bear web graphic that I discussed previously here, here, and here.

To refresh your memory, two points about this graphic stand out, both regarding polar bear population estimates:

1) The population estimates listed on the Nations map (copied below) add up to 22,600-32,000 – far higher than the official estimate of 20,000-25,000 polar bears worldwide.

2) The population estimates listed on the upper layer of the Subpopulation map add up to just 13,036 – not even close to the official estimate of 20,000-25,000 polar bears worldwide.
Continue reading

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Posted in Conservation Status, Population

Tagged IUCN, PBSG, Polar Bear Specialist Group, population estimate, population size, status, status table, Vongraven

New Chukchi Sea polar bear survey – exciting preliminary results

Posted on March 10, 2013 | Comments Off

Back in October, I wrote about US Fish & Wildlife biologist Eric Regehr comments about a recent survey of Chukchi Sea polar bears, the results of which are still not published. Since then, I’ve been able to track down a bit of information.

This project appears to have run for five years, from 2008 to 2011. The work was confined to the eastern (US) portion of the Chukchi, see maps below (Polar Bear News 2010; Rode and Regehr 2010). Researchers were doing mark-recapture work with helicopters, putting radio collars on some females and radio ear tags on a few males. They worked primarily in March and April (mating season for polar bears), operating entirely on the offshore sea ice – working, I might add, on bears that technically speaking do not exist, since the official population estimate for this region is “zero” (they are not included in the global estimate of 20,000-25,000, see pdf here,, discussed here).

Figure 1. Chukchi Sea – getting you oriented. Note the location of Kotzebue Sound, northeast of the Bering Strait. Map from Wikipedia.

In 2012, US Fish & Wildlife biologist Eric Regehr told reporter Jill Burke at Alaska Dispatch that they found the bears were “reproducing well and maintaining good body condition.” I’ve finally found some details regarding what he meant by that statement (although no final reports or peer-reviewed papers are out, see footnote below).

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Posted in Life History, Population, Sea ice habitat

Tagged Bering Sea, Chukchi, Polar Bear Specialist Group, population estimate, Regehr, Rode, triplets, unpublished data