[Updates: Note correction to point 6 and links added at the end of the post]
Polar Bears International has mustered the UK newspaper, The Guardian, to provide free publicity for a “save the polar bear” propaganda event coming up tomorrow, November 6.
From The Guardian Environment Blog:
“On Wednesday, 6 November at 10am EST and 3pm GMT you will have a chance to ask a scientist [Steven Amstrup] and a conservationist [Krista Wright] about the latest research on the state of polar bears – and the efforts to protect them.”
The “participants” of this webchat are Polar Bears International (PBI) employees. PBI is a lobbyist organization that uses its influence to pressure politicians and supposedly impartial scientific organizations, like the IUCN Polar Bear Specialist Group (PBSG), to make decisions that fit their agenda. The PBI rallying cry is “Save Our Sea Ice.” They are committed to promoting legislation to curtail supposed effects of anthropogenic global warming and are using polar bears as a tool to do so.
Dr. Steve Amstrup is now a full-time, professional activist and spokesperson for PBI (“Chief Scientist and Vice President”), a job he took on after a long career as a polar bear biologist. Arranging “webchats” like this is part of the job he is now paid to do.
Krista Wright has a Bachelors degree in Outdoor Education and has worked for NGOs for more than 20 years. She joined PBI in 2009 and is now the Executive Director (i.e., an administrator). She is described as “a passionate conservationist who is deeply concerned about the effects of global warming on polar bears, the Arctic, and the planet.” She brings emotion to this event, not science.
Below I dissect some of the fear-mongering background presented at The Guardian, one point at a time; Guardian quotes are in italics, numbered; my responses are below, with links to pertinent previous posts that are fully referenced:
[Links to video and the webchat Q & A have been added at the end of this post as updates]
1. Polar bears are threatend by melting Arctic sea ice [photo caption].
By “threatened” they mean sometime in the future, based on computer models. Polar bears are not currently threatened or endangered – they have a healthy global population distributed throughout their traditional range.
By “melting Arctic sea ice” they mean the difference between the recent seasonal minimum reached in September vs 30-odd years ago when satellite records began. But thirty years worth of records is one data point in climate terms, which is not nearly enough to establish a trend or draw climatic conclusions.
2. But the powerful beasts are acutely vulnerable to climate change.
Polar bears have lived through at least three interglacial periods with climate much warmer than today – and yet, by the time whalers started killing them on a large scale in the late 1800s, polar bears were astonishingly abundant. As it turns out, like many other species, polar bears are acutely vulnerable to wanton slaughter. This stopped in 1973 by international agreement and populations recovered. Local over-harvesting, however, may still be a concern.
3. How much time do they have left?
Amstrup’s models say 45 years or so for some populations (like W. Hudson Bay, Davis Strait and S. Beaufort). However, some important assumptions critical to these models turn out to be not true. Chukchi Sea bears, for example, should have been suffering due to “one of the highest rates of sea ice loss in the Arctic,” but a recent study showed they are not only doing better than they were in the 1980s, they are doing better than almost all other populations – see more evidence here.
4. On 6 November, Guardian readers will have a chance to catch up on the latest research on polar bears in a warming Arctic in a live chat with leading polar bear scientists and conservationists.
Perhaps PBI has located one or several bears that are markedly thinner than others that they know will make good video footage. They won’t tell you this is entirely normal.
“Starvation of independent young as well as very old animals must account for much of the natural mortality among polar bears… Also, age structure data show that subadults aged 2-5 years survive at lower rates than adults (Amstrup 1995), probably because they are still learning hunting and survival skills.” [Amstrup 2003].
Below is a photo of a starving bear (not an unusual occurrence, as starvation is probably the most common cause of death, see here and Featured Quote #44): let me know if they show pictures of dozens of bears in this condition. If so, I’ll report it.
5. Put simply, polar bears are running out of ice.
It’s certainly true that there has been markedly less ice at the end of the summer than there was 20 years ago but the amount of summer ice is irrelevant to polar bears – and research by polar bear biologists themselves shows this to be true.
6. There are thought to be between 20,000 to 25,000 bears across the polar region, in Canada, Alaska, Greenland, Norway, and Russia.
Careful dissection of the creative accounting done by the IUCN Polar Bear Specialist Group – of which Amstrup is a long-time member – suggests that this number
should be 22,650-30,700 is an increase from the 2001 estimate. The 2013 PBSG estimate does not take into account the thousands of bears known to live in the Chukchi Sea, East Greenland, and the Laptev Sea — perhaps 6,000 bears or more (see Fig. 2), although scientific estimates are not yet available.
7. Scientists for the US Geological Survey predicted in 2007 that two-thirds of those bears could be gone by mid-century if current warming trends continued.
Warming has already been less than predicted, yet summer ice extent has continued to decline, suggesting poor correspondence between global temperatures and summer sea ice extent.
As far as the polar bear models go, Amstrup’s “professional opinion” regarding how polar bears would react to changes in September sea ice was the only input used for those models (Amstrup et al. 2008, see quote below). But it turns out, he was wrong: the bears have not been responding as predicted.
“Our BN [Bayesian Network] stressor model was based on the knowledge of one polar bear expert (S. Amstrup), who established the model structure and probability tables according to expected influences among variables.” [Amstrup et al. 2008:219]
8. The sea ice cover – for which the bears are uniquely evolved – has been shrinking under climate change, forcing the bears off of the ice for longer periods and away from their main food source: seals.
Only the summer ice extent is “shrinking” markedly. Ice in the spring has changed very little over the last 30 years, as has early summer ice. Spring and early summer ice is the most important for feeding on young seals, which there are more of because of longer ice-free periods. Ringed seals in the Chukchi are doing better than they were in the 1980s, meaning there are more seals for polar bears to eat.
9. Their bodies are uniquely evolved for the extreme conditions. The bears, insulated by a two to four inch layer of blubber, can withstand extreme cold. They can swim up to 40 miles of freezing seas in a stretch and attain speeds of 25 miles per hour over ice.
Blubber is not primarily for insulation from the cold: fat is an essential buffer against times when there is little or no food. Western and southern Hudson Bay bears are at their fattest during the height of summer, not the middle of winter. Fat storage is the most important Arctic adaptation – think fat seals, fat walrus, fat bowhead whales and fat beluga.
10. But those attributes don’t help off the ice. Climate change in a warming Arctic is forcing the bears off the ice earlier each spring and delaying freeze-up later into the autumn.
Changes in breakup dates in Western Hudson Bay and elsewhere in the Arctic have not impacted the critical spring feeding period (March-June) more than a handful of times in the last 30 years.
11. On the frontline of those changes are the bears of western Hudson’s Bay, Canada, the southern-most population of polar bear. Scientists believe they can best predict the future for polar bears under climate change, by studying these bears.
Western Hudson Bay does not have the “southern-most population of polar bears” by a long shot. PBI wants you to think that because the two truly southern-most populations – Southern Hudson Bay and Davis Strait – are doing just fine. Western Hudson Bay bears are not typical of bears throughout the Arctic for a number of reasons (see here and here).
12. This area of Hudson’s Bay has always been ice-free in the summer months, but now the season of open water begins earlier each spring and lasts longer into the autumn.
The open water changes referred to have not happened “each spring and autumn” but a few years out of 30 – breakup and freeze-up in Hudson Bay is highly variable. Bears came ashore in 2009 as late as they did in 1992.
13. That forces bears onto land for longer intervals – and into increasingly close proximity with humans living in the town of Churchill, Manitoba. The town now runs a polar bear alert programme to keep both populations – humans and bears – safe.
Breakup in Hudson Bay was about average this summer and freeze-up is not long off, see yesterday’s post here. Alerts and patrols don’t help if folks get complacent about safety, but even with precautions, tragedies sometimes happen.
14. Scientists, meanwhile, come to Churchill every autumn to track the bear and monitor their conditions as they return to the ice after the long summer weeks of fasting.
So where are the published reports on the recent data they’ve collected? There has been hardly anything published on western Hudson Bay bears since 2004 and some of the data is 20 years old.
15. The latest research suggests that polar bears are shrinking because of their months off the ice, and away from their main food source of seal.
Again, let’s see the published data. “Ian Stirling, unpublished data” is not good enough.
16. Some female polar bears are losing so much fat they can no longer produce healthy cubs. More cubs are dying at a younger age.
Again, let’s see the published data. “Ian Stirling, unpublished data” is not good enough.
17. The biggest fear for scientists now is that the polar bears may be slowly ageing out of existence. Is there any hope left for polar bears?
What utterly unscientific nonsense. This kind of statement may increase revenues for Polar Bears International but it has nothing to do with science.
Polar bears have been saved. Polar bear populations need to be studied, monitored and managed, but surely this can be done without the hysteria promoted by Polar Bears International and the IUCN Polar Bear Specialist Group.
Update Nov. 5, 2013, 5:06 PM Pacific time:
Video from The Guardian: “Polar bears fight for survival as sea ice melts” – http://t.co/GCg7p06Efe You might notice, if you look, that there are no starving polar bears in this video – see for yourself! I wonder where they all are, all the starving polar bears?
Update Nov. 6, 2013, 10:00 PM:
For anyone who is interested, I’ve made a pdf of The Guardian Q & A’s from the “webchat” that went on today (here). Seventeen questions were answered (unless I missed a few minor ones) — not what I would call an overwhelming response.
Amstrup, S.C. 2003. Polar bear (Ursus maritimus). In Wild Mammals of North America, G.A. Feldhamer, B.C. Thompson and J.A. Chapman (eds), pg. 587-610. Johns Hopkins University Press, Baltimore.
Amstrup, S.C., Marcot, B.G., Douglas, D.C. 2008. A Bayesian network modeling approach to forecasting the 21st century worldwide status of polar bears. Pgs. 213-268 in Arctic Sea Ice Decline: Observations, Projections, Mechanisms, and Implications, E.T. DeWeaver, C.M. Bitz, and L.B. Tremblay (eds.). Geophysical Monograph 180. American Geophysical Union, Washington, D.C. http://onlinelibrary.wiley.com/doi/10.1029/180GM14/summary and http://alaska.usgs.gov/science/biology/polar_bears/pubs.html