Freeze-up in the Arctic (~October-November) is important to polar bears because for those animals that have spent the ice-free period on shore (not all do), it marks the end of their summer fast — they can finally resume seal hunting.
Polar bears in the most southern regions, like Southern Hudson Bay, Western Hudson Bay, and Davis Strait (see Fig. 1), routinely experience the longest ice-free period. As these bears all spend the summer on shore, they appreciate a timely return of the ice.
Figure 1. Polar bear subpopulations defined by the IUCN Polar Bear Specialist Group (PBSG), with a few extra labels added. I’ve rotated the original map 90 degrees (right) to make it easier to relate to the ice maps below. WH is Western Hudson Bay; SB is Southern Beaufort. Courtesy PBSG. Click to enlarge.
Southern Hudson Bay bear populations routinely experience an ice-free season that is just as long as it is for Western Hudson Bay bears. However, Southern Hudson Bay polar bears numbers have remained stable over the last 30 years. Some folks insist that Western Hudson Bay bear numbers are shrinking to a worrisome degree, despite indications that the recent decline could be nothing more than a return to sustainable levels after a rapid population increase in the late 20th century (similar to changes documented for the Davis Strait and Barents Sea subpopulations).
Have a look at how sea ice – essential polar bear hunting habitat – has developed within these regions over the last 10 days or so (end of November 2013) and how November 2013 compares to November 1979. The ice maps tell the freeze-up story.
Posted in Sea ice habitat
Tagged Barents Sea, Canadian Ice Service, Davis Strait, Hudson Bay, polar bear habitat, Polar Bear Specialist Group, polar bears, prolonged ice-free season, sea ice extent, Southern Hudson Bay, Svalbard, western hudson bay
The latest polar bear propaganda emanating from The Guardian is unscientific nonsense fed to them by activist Canadian polar bear researchers: “Polar bear numbers in Hudson Bay of Canada on verge of collapse.”
This episode of Goldenberg’s polar bear grandstanding includes a photo caption with a totally unsubstantiated claim that some folks might call a lie:
“Melting ice is cutting polar bears off from their food source in Hudson Bay, and death rates have soared.”
“Death rates have soared”? Where are all the bodies? Show us the starving bears!
In fact, the ice of Hudson Bay melts every summer and always has done. When it does, polar bears go ashore and live off the many inches of stored blubber they put on during their spring feasting on fat baby seals. The last three years, the open-water season has been only about two weeks longer than it was in the 1980s. There has been no steady increase but lots of variability.
Below I dismantle the rest of this transparently political posturing ahead of the international polar bear forum next week.
Posted in Advocacy, Conservation Status, Sea ice habitat
Tagged Amstrup, breakup, climate change, conservation, death rates, Derocher, Environment minister, freeze-up, Goldenberg, Hudson Bay, melting ice, Nick Lunn, open-water season, polar bear, starving polar bears, Stirling, western hudson bay
International Forum on Conservation of Polar Bears
December 3-6, Moscow.
[Updated November 30, 2013]
If you’ve wondered why there’s been so much polar bear hype circulating over the last couple of weeks, the reason is almost certainly this upcoming meeting.
This year marks the 40th anniversary of the signing of an international agreement to protect polar bears from commercial and unregulated sport hunting. Next week, the five Arctic nations that signed the original agreement will meet again, in Moscow, to renew their vows.
One of stated goals of the meeting is to redefine the original agreement, which focused on over-hunting (see the complete draft agenda here). Can you guess what the changes will involve?
Posted in Conservation Status
Tagged Amstrup, Arctic nations, Bayesian models, Circumpolar Action Plan for Polar Bear Conservation, conservation meeting, international agreement, IUCN, Leona Aglukkaq, meeting of the parties, Moscow, polar bear conservation, polar bear forum, Polar Bear Specialist Group, polar bears, sea ice, USGS
Poor polar bear researchers: there are few full time jobs worldwide and research is underfunded.
This is not my opinion but the facts according to Andrew Derocher and Ian Stirling (2011) — see Fig. 1 and 2 below. I do not dispute them.
Figure 1. The distribution of full-time polar bear researchers worldwide. From Derocher and Stirling 2011, invited speaker presentation to the 2011 Polar Bear Meeting in Nunavut, Oct 24-26.
Since Derocher and Stirling have raised the issue, I contend it’s perfectly valid to ask: are polar bear biologists who proclaim their heartfelt fear for the future of polar bears at every opportunity behaving as advocates for polar bears or protecting their own careers?
Posted in Advocacy, Conservation Status
Tagged 2011 polar bear meeting Nunavut, Circumpolar Action Plan for Polar Bear Conservation, conflict of interest, conservation, COSEWIC, Derocher, Eastern Beaufort, expert testimony, government jobs, grant funding, helicopter survey, jobs, oil money, polar bear research, Southern Beaufort, Stirling, western hudson bay
There was a story in The Guardian on Friday (November 21) about an issue I covered earlier this year (in January): Canada under international pressure to list polar bears as threatened, so far holds out.
This time, Suzanne Goldenberg’s headline proclaims “Canada’s refusal to protect polar bears comes under scrutiny.”
The story is all about a petition filed by the ever-litigious Center for Biological Diversity (CBD) to the North American free trade organization, the Commission for Environmental Co-operation (CEC), pdf here. The CEC, it seems, has now agreed to investigate the CBD claims.
At issue here is the fact that Canada hasn’t done exactly what the US has done in terms of enacting formal legislation to protect polar bears. Canada, home to 2/3’s of the worlds polar bears (as well as a relatively large Arctic human population) vs. the USA, with the fewest bears in the world but perhaps the loudest, “we know best” attitude. Canada has not declared polar bears to be a species threatened with extinction but the Center for Biological Diversity not only thinks otherwise but thinks someone should force Canada to change its opinion.
It’s more of the same bullying of governments by environmental groups that we’ve come to expect, aided and abetted by activist polar bear biologists.
That said, I suggest you brace yourselves: it’s only going to get worse. We can expect even more of this over the next few weeks, because an important international polar bear meeting is coming up in early December. I expect that the propaganda, aided by an all-too-willing-media, is going to get intense. Continue reading
Posted in Advocacy, Conservation Status
Tagged activists, bullies, Canada, Center for Biological Diversity, climate change, COSEWIC, Derocher, Goldenberg, PBSG, petition, polar bears, SARA, special concern, threatened
[Update Nov. 23, 2013: I’ve added a few comments, noted, in the text]
This is a follow-up to an earlier post, Polar bear problems in N Hudson Bay not due to late freeze-up, to counter some misinformation that’s being circulated about the history of Hudson Bay freeze-up dates.
Polar bear biologists working in Western Hudson Bay published new definitions of breakup and freeze-up earlier this year. The new method better reflects how polar bears interact with seasonal changes in sea ice on the bay.
Formerly, 50% ice coverage levels were used to assign the date when major ice change phenomena were reached each year (breakup in summer, freeze-up in fall (e.g. Gagnon and Gough 2005). The new method (Cherry et al. 2013, see discussion here) defines breakup at 30% ice coverage and freeze-up at 10%.
Cherry and colleagues had a fairly complicated method of defining 30% coverage for breakup in Western Hudson Bay. However, freeze-up in the fall is much simpler because ice always forms first along the western shore, starting in the north.
This means that the weekly graphs of ice development provided by the Canadian Ice Service for Hudson Bay, which are expressed as a percentage (just like the Cherry et al. study), can be used to compare freeze-up dates historically.
These graphs refute the absurd claim that freeze-up on Hudson Bay has been “one day later each year” over the last 30 years – an assertion repeated just the other day at PBI. Let’s take a closer look, shall we?
What did I tell you, back in mid-September?
Have a look at all the polar bear habit, ten days shy of the end of November!
Figure 1. MASIE sea ice extent for November 18, 2013 (using US National Ice Center data). You have to look closely but there is indeed ice forming around Svalbard (just above the tip of Greenland) and in James Bay (southern Hudson Bay). Click to enlarge. High resolution map here.
Figure 2. Canadian Ice Service map. Ice developing rapidly in northern Hudson Bay, Foxe Basin and Davis Strait (between southern Greenland and Baffin Island), with ice also forming along the shore in James Bay (the southern-most region where polar bears are onshore at the moment). Click to enlarge.
Posted in Sea ice habitat
Tagged Canadian Ice Service, Davis Strait, Foxe Basin, James Bay, polar bear habit, polar bears, sea ice extent, sea ice maps, Southern Hudson Bay, Svalbard, western hudson bay