National Geographic has just posted an exclusive video shot mid-summer of 2015 of a male polar bear killing and eating a young cub.
It’s worth watching (23 February 2016; “Polar bear cannialzies cub“) [update: Youtube version posted below]. It was filmed in 2015 in Baffin Bay at mid-summer (during either their July 28-Aug 9 or Aug 7- 19 cruise; pdf of itinerary, dates and prices – oh my god, the prices! here). [Summer is 1 July-30 September]
You’ll soon realize the male bear was not thin or starving (as was true of a much-publicized 2011 event captured on film off Svalbard).
It is also obvious based on the dates listed above that this incident debunks the explanation that cannibalism by adult males is driven primarily by their desire to mate with the mother of the consumed cub: this incident occurred sometime between August 7 and August 19 (as I was informed via email, by a reader on one of those two cruises), which is well past the breeding season for polar bears. A male bear would not still have viable sperm by August and a female could not be forced into estrus. [added 26 February 2016]
National Geographic is already hyping this incident as more evidence of climate change harming polar bears, as the article accompanying the video suggests. However, this is just the typical oversell that accompanies much to do with polar bear these days.
The bear was not “driven to desperation” : he simply took advantage of a rare chance to eat during the summer:
“Without the ability to hunt seals, polar bears may be driven to ever more extreme cannibalism, if they’re not already.”
It’s clear to me that this was an opportunistic kill made at a time of year when few seals are available, as even Stirling admits. It reiterates the point I’ve made many times before, that polar bears on the sea ice in summer have few feeding opportunities.
Incidents of cannibalism cannot be said to be increasing because there is no scientific baseline for which recent occurrences can be compared. Scattered anecdotal reports of any behaviour cannot be touted as evidence for a trend even though they may be of interest and worth recording.
UPDATE 23 February 2016: Video now posted on Youtube, see it copied below:
Here’s a new resource for cooling the polar bear spin, all in one place. I’ve updated and expanded my previous summary of reasons not to worry about polar bears, which is now two years old. In it, you’ll find links to supporting information (including previous blog posts of mine that provide background, maps and extensive references), although some of the most important graphs and maps have been copied into the summary. I hope you find it a useful resource for refuting the spin and tuning out the cries of doom and gloom about the future of polar bears — please feel free to share. Pdf here of the text below.
This is the 1st anniversary of Canada providing population estimates and trends independent of the pessimistic prognostications of the IUCN/SSC Polar Bear Specialist Group (PBSG) — so let’s celebrate the recent triumphs and resilience of polar bears to their ever-changing Arctic environment.
Posted in Advocacy, Conservation Status, Summary
Tagged arctic sea ice, cannibalism, conservation, den collapse, Environment Canada, IUCN, polar bear, Polar Bear Specialist Group, polar bear status, population, Red list, spin, starving, status, summary, threatened, vulnerable
If I was invited by USA TODAY to discuss how climate change is affecting polar bears now – summed up in three talking points – this is what I’d say. I’d use some meaningful images rather than cute pictures of cuddly bear cubs and I’d provide links to my work with references and details to back up my answers.
Compare my responses to those supplied by Steve Amstrup in his capacity as spokesperson for Polar Bears International (“Save our sea ice!”) to Jolie Lee at USA TODAY last week, who’s word is expected to be taken as gospel.
Posted in Advocacy, Cannibalism, Polar bear attacks
Tagged Amstrup, Arviat, cannibalism, climate change, disappearing population, fasting, global warming, hibernation, human-bear conflicts, melting ice, polar bear, polar bear attacks, starving bears, Stirling
Remember Ian Stirling’s claim that late freeze up in Western Hudson Bay in 2009 was forcing polar bears to resort to cannibalism (here and here), with gut-wrenching images and video provided for the media? Or Steve Amstrup’s claim for a similar phenomenon in the Southern Beaufort in 2004?
I pointed out that Stirling’s claim was way overblown and that Amstrup’s incidents were almost certainly the result of heavy ice in the spring (not low ice in summer), similar to the heavy ice conditions and polar bear starvation documented in the same region back in 1974-1976.
It turns out that the heavy ice conditions documented in the Eastern Beaufort in the mid-1970s had much broader effects on polar bears and ringed seals than has been appreciated.
Posted in Cannibalism, Conservation Status, Sea ice habitat
Tagged Beaufort Sea, Bering Sea, body condition, cannibalism, Chukchi Sea, heavy sea ice, Ian Stirling, Jack Lentfer, John Burns, mortality events, polar bear, Polar Bear Specialist Group, ringed seals, spring sea ice, starving polar bears, Steven Amstrup, summer ice minimum
The polar bear biologists and professional activists of the IUCN Polar Bear Specialist Group (PBSG) continue to insist that since 1979 increasingly smaller amounts of Arctic sea ice left at the end of summer (the September ice minimum) have already caused harm to polar bears. They contend that global warming due to CO2 from fossil fuels (“climate warming” in their lexicon) is the cause of this decline in summer ice.
In a recent (2012) paper published in the journal Global Change Biology (“Effects of climate warming on polar bears: a review of the evidence”), long-time Canadian PBSG members Ian Stirling and Andrew Derocher (both of University of Alberta) summarized their position this way:
“Climate warming is causing unidirectional changes to annual patterns of sea ice distribution, structure, and freeze-up. We summarize evidence that documents how loss of sea ice, the primary habitat of polar bears (Ursus maritimus), negatively affects their long-term survival”
I’ve spent the last year examining their evidence of on-going harm, but in addition, I’ve looked at the evidence (much of it not mentioned in the Stirling and Derocher paper1) that polar bears have either not been harmed by less sea ice in summer or have thrived in spite of it.
This is a summary of my findings. I’ve provided links to my original essays on individual topics, which are fully referenced and illustrated. You are encouraged to consult them for complete details. This synopsis (pdf with links preserved, updated; pdf with links as footnotes, updated) complements and updates a previous summary, “Ten good reasons not to worry about polar bears” (pdf with links preserved; pdf with a foreword by Dr. Matt Ridley, with links as footnotes).
Update 8 September 2013: to include links to my post on the recently published Chukchi population report; updated pdfs have been added above.
Update 22 January 2014: added figure comparing March vs. September sea ice extent using the same scale, from NOAA’s “2014 Arctic Report Card,” discussed here.
Posted in Conservation Status, Population, Sea ice habitat, Summary
Tagged Arctic, Barents Sea, Beaufort Sea, body condition, breakup dates, cannibalism, Chukchi, climate change, climate warming, Davis Strait, death spiral, Derocher, global warming, harm to polar bears, heavy sea ice, Hudson Bay, hybridization, ice-free, negative effects, polar bear, polar bear numbers increasing, Polar Bear Specialist Group, Polar Bears International, prolonged ice-free season, ringed seals, sea ice, sea ice decline, September ice minimum, Stirling, summary, summer ice minimum, victim of climate change