Arctic sea ice is spreading out quickly from its central basin summer refuge – according to this NSIDC Masie ice chart, it has already grown more than 2 mkm2 beyond the annual minimum reached in early September. Ice is already pushing south into the eastern Beaufort and the archipelago of Franz Josef Land in the Barents Sea.
Over the next couple of weeks, shorefast ice will start forming along the coasts of North America and Eurasia (see the first bits off Alaska in the 21 October CIS map below), which will eventually meet the expanding Arctic Basin pack to fill the Basin and Canadian Arctic Archipelago with ice – as it has done for eons.
The evidence from the last decade or so suggests that by the end of October, most of the Arctic north of the 79th parallel (see map below) will be filled with ice – although the Chukchi Sea (north of the Bering Strait) may not fill until sometime in November:
Polar bears usually resume hunting as soon as sea ice conditions permit in the fall, since it’s their last chance to top up their fat reserves before the dark and cold of winter when hunting may become next to impossible.
I’ve copied ice charts from the Masie archives for some previous years at 31 October below.
Posted in Life History, Sea ice habitat
Tagged 79th parallel, Arctic, Barents Sea, Beaufort Sea, Canadian Arctic Archipelago, Chukchi Sea, fall ice growth, hunting, MASIE, NSIDC, platform, polar bears
PBS has published a bizarre poor-starving-polar-bears story that uses pictures of fat, healthy bears to illustrate the supposed desperation of malnourished bears of the Southern Beaufort Sea that is blamed on declining sea ice.
The photo of the fat bear above, taken by the Kaktovik resident quoted in the 15 October 2016 PBS story, Polar bears, growing desperate for food, threaten native Alaskans, accompanies this statement:
“While images of malnourished polar bears have become a national symbol of the effects of climate change, they are a front line reality for Native Alaskans, who face them on their own property and do not want them to get hurt.”
Except this is not a story about starving bears but too many fat bears hanging around one particular community looking for other kinds of food – after being lured in by the enticing smell of rotting whale meat left onshore by the residents.
If photos of starving Beaufort bears existed that PBS could have used to illustrate this story, I’m certain those photos would have been used. But virtually all of the pictures I’ve seen of Kaktovik bears are the epitome of health – fat and sassy – but none that could be described as starving.
It turns out that while native Kaktovik residents have profited from tourists and journalist who have shown up in droves to view the large numbers of bears attracted to the bone piles left after butchering summer-caught bowhead whales, the bears have also put the community at risk of personal attack and loss of stored food. Who would have thought?
Residents of Kaktovik (see map below) have unwittingly enticed these polar bears ashore and now must deal with the consequences. As the residents of Churchill discovered decades ago, having polar bears close to your community comes with benefits, problems – and danger.
There is no doubt that Kaktovik has a polar bear problem but it cannot plausibly be blamed on anthropogenic global warming, retreating sea ice, or starving bears – an irresistible attractant close to the community is the cause and solutions must be found to keep residents safe and their food secure. The PBS article discusses a few of those solutions. Some quotes and background below.
Posted in Life History, Polar bear attacks, Sea ice habitat
Tagged Atwood, Barter Island, bone piles, climate change, desperate, facts, fat bears, global warming, Kaktovik, malnourished, polar bears, retreating sea ice, sea ice, Southern Beaufort, starving, stressed
A quiet year for problems in the polar bear capital of the world (Churchill, Manitoba) so far – despite this year tying for the second-lowest minimum since 1979 – and the ice is growing fast. In fact, Arctic ice growth in the second half of September was rapid and there is now more ice than there was at this date in 2007 and 2012 (when polar bears in those regions considered most at risk did not die off in droves).
Pessimistic polar bear specialists are wrong – polar bears are much more resilient to low sea ice levels in summer than they assume: their own data from low summer ice years proves it. If you’ll recall from my previous post, polar bears seem to have barely survived the extensive sea ice coverage during the Last Glacial Maximum – in other words, too much ice (even over the short term) is their biggest threat. Polar bear numbers, as confirmed by the latest estimates in the 2015 IUCN Red List assessment, are higher now than they have been since the 1960s, despite almost 10 years of summer sea ice minimums below 5.0 mk2.
Churchill Polar Bear Alert reports and Arctic sea ice comparisons at this date, in detail below.
Posted in Conservation Status, Polar bear attacks, Sea ice habitat
Tagged Arctic, attacks, biggest threat, Churchill, facts, ice growth, last glacial maximum, minimum, polar bear, polar bear alert, population size, problem bears, Refuge, resilience, sea ice, September, summer, thick spring ice
All three polar bear females tagged in the Southern Beaufort Sea far west of Kaktovik (near Barrow) spent all or most of September onshore in the Northern Beaufort area of Canada.
Posted in Life History, Sea ice habitat
Tagged Banks Island, Barrow, Beaufort Sea, boundaries, Kaktovik, mixing, polar bear, satellite radio collars, sea ice, subpopulations, tracking polar bears, USGS, Western Arctic
A report from the CBC this morning (with video) of a large polar bear wandering about the village of Tuktoyaktuk on the (Canadian) shore of the Eastern Beaufort Sea on Thursday (29 September) that got very close to a group of children playing outside. Fortunately, no one was hurt.
That this was a rare event is evident in the awe and excitement in the voices of the residents as someone recorded the movements of the bear through town (picture quality is not the best, but clear enough).
As I’ve said before, with more bears we can expect more interactions with people and more sightings like this that haven’t happened in decades. Map and quotes below.
Posted in Polar bear attacks, Sea ice habitat
Tagged attacks, Beaufort Sea, conflicts, declining sea ice, encounters, polar bear, sea ice, sighting, summer, thick spring ice
A large polar bear population with lots of adult males – due to bans on hunting – means more survival pressure on young bears, especially young males. To blame more problems with young male bears on lack of sea ice due to global warming ignores the downside to the reality Norway asked for when it banned hunting more than 40 years ago.
More hungry young males coming ashore looking for food is one of the potential consequences of living with a large, healthy population of polar bears. Biologist Ian Stirling warned of such problems back in 1974.
UPDATE: added below 6 Oct. 2016, statistics of defense of life shootings of polar bears in Svalbard since 1973.
Svalbard area polar bear numbers have increased 42% since 2004 and more hungry young polar bears almost certainly mean more polar bear problems, as folks in Svalbard (see map and quotes below) have experienced this year.
Posted in Conservation Status, Life History, Polar bear attacks, Sea ice habitat
Tagged attack, competition, facts, feeding, global warming, human-polar bear conflicts, numbers, polar bear, population size, problem bears, sea ice, subadult males, Svalbard, young bears
This short BBC video shows why polar bears are so often unsuccessful in their summer hunts – adult bearded seals are the species most often available on the ice. These seals are not only predator-savvy but there are lots of escape routes in the melting ice, and this has always been so.
“Hungry polar bear surprises a seal – The Hunt: Episode 2 Preview – BBC One”
Melting ice in summer is not a new phenomenon (e.g. NASA photo below from mid-July 2016) – Thomas Grenfell and Gary Maykut described the process of melt pond development back in the 1970s:
“Melt ponds reach the maximum extent shortly after the disappearance of the snow, when they may cover upwards of 50% of the ice.”
Melting summer ice has always made it challenging for polar bears to catch seals, as this quote from Ian Stirling (1974) show, based on his work in the Central Canadian Arctic in the summer of 1973 (July and August):
“There is a great abundance of natural holes in the ice during summer, anyone of which a seal could surface through. “
This is still true in areas like the Southern Beaufort Sea today (e.g. Whiteman et al. 2015): the ice melts and in some areas, disappears completely in summer.
It’s why polar bears – unlike other species of bears in summer – depend on their stored fat to see them through until the ice reforms in the fall.
The meme “If there’s no ice, there’s no ice bear” is political-style rhetoric, not science.
[When polar bear scientists say “sea ice” or “ice” – they mean summer sea ice. Sea ice in winter and spring are not predicted to decline by 2100 to any appreciable degree and that has been true since sea ice predictions began]
Polar bears in Hudson Bay and Davis Strait routinely go 4-5 months without sea ice in the summer and have done since studies on them began. Yet, all of the polar bear subpopulations in Hudson Bay and Davis Strait are stable or increasing.
Posted in Life History, Sea ice habitat
Tagged bearded seals, Davis Strait, facts, Hudson Bay, hunting, no ice, no ice bear, platform, polar bear, sea ice, seals, summer