Two days ago the mainstream media was lamenting that polar bears should be listed as threatened with extinction because of disappearing sea ice all a consequence of global warming.
Today the media is reporting that a giant ice shelf the size of 11,000 football fields has snapped free from Canada’s Arctic and has formed an ice island. Furthermore, this ice island is likely to end up as sea ice in the very places scientists are complaining there is not enough of the stuff for the big bears…
“Within days, the floating ice shelf had drifted a few kilometres offshore. It travelled west for 50 kilometres until it finally froze into the sea ice in the early northern winter… Prevailing winds could then send the ice island southwards, deep into the Beaufort Sea.”
Well isn’t this good news for polar bears?
It could be, if there was any truth to the story that polar bears are threatened with extinction from a reduced area of sea ice.
But the whole “disappearing sea ice threatens polar bear’s survival” story is in reality a farce.
While the area of sea ice has been declining over the last couple of decades, the number of polar bears has actually been increasing. That’s right increasing!
So it is very wrong for the Australian Broadcasting Corporation to uncritically report that: “The World Wide Fund for Nature says the declining number of polar bears is a major warning on the impact of climate change.”
There were only about 5,000 polar bears in 1970, numbers depressed by hunting. There are now about 25,000 polar bears. The increase a consequence of agreements to restrict hunting under quota systems.
The biggest threat to discrete populations of polar bears continues to be illegal hunting in places like the Chukchi sea and Greenland’s failure to agree to the quota system.
If the extent of sea ice continues to decline in places like Hudson Bay and the Beaufort Sea, these populations of polar bears can move north to where there is more sea ice with ringed seals, or they might simply switch to hunting seals that prefer warmer weather.
As I have previously written, the two polar bears living happily at Sea World, on Queensland’s Gold Coast, enjoying watermelons and museli bars, are evidence of the capacity of this big bear to adapt, including to warm weather.
——————
The mass of ice fell away 16 months ago but scientists have ony just realised because it all happened at a remote locality off the coast of Ellesmere Island which is about 800 kilometres south of the North Pole.
The issue of environmentalists and scientists taking advantage of the popularity of polar bears and drawing rediculous conclusions from the available data all to progress their global warming agenda is reviewed in a piece I wrote for the IPA Review earlier this year entitled ‘Polar Bear Politics: Underestimating the survival capacity of one popular bear’.
There is an old blog post from 25th October 2005 here (Polar Bears on Thin Ice) and another from 3rd May 2006 here ( 16,119 Species Threatened with Extinction?) and I also wrote something on 30th May 2006 here (Polar Bear Politcs: Misrepresenting the Nature of One Smart Bear).
Jennifer Marohasy BSc PhD is a critical thinker with expertise in the scientific method.
Jennifer,
Actually, the Norwegian Gov’t is extremely worried about climate change. As I have mentioned before, probably the nation that is most worried about global warming, due to its consequences for its basic industry, fishing.
Increased surface temperature as well as increased temperature in the deepest ocean’s layers have already had some impacts on some fish stocks, report fishermen.
Re Svalbard and polar bears, Schwartzenegger is right now invited to Svalbard to witness the climate change, by the Gov’t.
Correction: Arni will be invited to Svalbard…
It is very strange Jen…my media reports that polar bear population is decreasing…. gonna take a closer look at the issue…
Actually the drifting ice shelf is extremely bad news for the environment…it seems like it is a big threat to oil installations.
Re polar bear populations, 5 of 19 populations worlwide is showing decline , in comparison to only 1 , five years ago.
Admit though that some animals are used as icons…
Ann,
1. Please define “decline”. I know they have found that some bears are a bit thinner. But population numbers and longevity are generally on the increase.
2. Isn’t the ice shelf now sea ice? Is sea ice a threat to oil installations?
Hi Jennifer,
Here’s my link:
http://www.stopglobalwarming.org/sgw_read.asp?id=10342712182006
Re the ice shelf threatening oil installations, read that this morning in Norwegian paper Aftenposten. Unfortunately, I have problems with my computer, so can’t recheck the article… maybe George can read it and report back re the oil installations???
Jennifer you’ve admitted that GW is happening (irrespective of cause). Do you reckon that the ice body is accumulating faster than big chunks are migrating to Starbucks? Where is the evidence that polar bear habitats are not threatened? “Sea ice has declined considerably over the past half century.” Food for denialist thought. The scientists haven’t ignored the adaptability of polar bears either. See below (research you should have done before you wrote ignorant evidence-free denialist pieces). What’s next? Surely the heat generated by all that extra polar bear biomass is causing the ice to melt so they should be culled before they destroy their own habitat.
From the red list (can’t link to it)
The assessment is based on a suspected population reduction of >30% within three generations (45 years) due to decline in area of occupancy (AOO), extent of occurrence (EOO) and habitat quality.
Polar bears rely almost entirely on the marine sea ice environment for their survival so that large scale changes in their habitat will impact the population (Derocher et al. 2004). Global climate change posses a substantial threat to the habitat of polar bears. Recent modeling of the trends for sea ice extent, thickness and timing of coverage predicts dramatic reductions in sea ice coverage over the next 50–100 years (Hassol 2004). Sea ice has declined considerably over the past half century. Additional declines of roughly 10–50% of annual sea ice are predicted by 2100. The summer sea ice is projected to decrease by 50–100% during the same period. In addition the quality of the remaining ice will decline. This change may also have a negative effect on the population size (Derocher et al. 2004). The effects of sea ice change are likely to show large differences and variability by geographic location and periods of time, although the long term trends clearly reveal substantial global reductions of the extent of ice coverage in the Arctic and the annual time frames when ice is present.
While all bear species have shown adaptability in coping with their surroundings and environment, polar bears are highly specialized for life in the Arctic marine environment. Polar bears exhibit low reproductive rates with long generational spans. These factors make facultative adaptation by polar bears to significantly reduced ice coverage scenarios unlikely. Polar bears did adapt to warmer climate periods of the past. Due to their long generation time and the current greater speed of global warming, it seems unlikely that polar bear will be able to adapt to the current warming trend in the Arctic. If climatic trends continue polar bears may become extirpated from most of their range within 100 years.
There is little doubt that polar bears will have a lesser AOO, EOO and habitat quality in the future. However, no direct relation exists between these measures and the abundance of polar bears. While some have speculated that polar bears might become extinct within 100 years from now, which would indicate a population decrease of >50% in 45 years based on a precautionary approach due to data uncertainty. A more realistic evaluation of the risk involved in the assessment makes it fair to suspect population reduction of >30%.
Other population stress factors that may also operate to impact recruitment or survival include toxic contaminants, shipping, recreational viewing, oil and gas exploration and development. In addition to this comes a potential risk of over-harvest due to increased quotas, excessive quotas or no quotas in Canada and Greenland and poaching in Russia.
This assessment was reviewed by all the participants at the 14th Working Meeting of the IUCN SSC Polar Bear Specialist Group held in Seattle, Washington, USA during June 20-24, 2005.
Citation: Schliebe, S. Wiig, Ø., Derocher, A. & Lunn, N. 2006. Ursus maritimus. In: IUCN 2006. 2006 IUCN Red List of Threatened Species.
The increasing changes in the sea ice that affect access to prey will have a negative effect on the bears. With less food, polar bears will fail to reproduce more often and give birth to smaller young that have higher mortality rates.
Polar bears may be forced on shore for extended periods and rely on fat reserves deposited the previous spring for survival. In such a situation they will be increasingly vulnerable to hunting if not regulated. If these periods become excessively long, mortality will increase. Sea ice is also used for access to den areas and if ice patterns change, existing den areas may be unreachable. Warmer temperatures and higher winds may reduce ice thickness and increase ice drift. Because polar bears must walk against the moving ice (like walking the wrong way on an escalator) increased ice movements will increase energy use and reduce growth and reproduction.
Polar bears are the apex predator and are exposed to high levels of pollutants that are magnified with each step higher in the food web. A key characteristic of the pollutants is that they tend to persist in the environment and resist degradation. Many of the organochlorine pollutants are lipophilic or “fat loving” and bond tightly to fat molecules. Polar bears are particularly vulnerable to organochlorines because they eat a fat rich diet. Ringed, bearded, and harp seals comprise the main food of polar bears and the blubber layer is preferentially eaten by the bears and subsequently, the intake of pollutants is high.
Certain areas of the Arctic, such as NE Greenland, the Barents Sea and the Kara Sea, have higher levels of pollutants. Based on studies in other species, it is reasonable to believe that the pollutant load of polar bears in some areas are negatively affecting the immune system, hormone regulation, growth patterns, reproduction, and survival rates of polar bears. Recent studies have suggested that the immune system is weaker in polar bears with higher levels of PCBs. A major concern with polar bears pertains to their reproductive system. There are suggestions that species with delayed implantation are more vulnerable to the effects of pollution through endocrine (hormone) disruption. Further, female polar bears are food deprived during gestation their pollution loads increase because as they use their fat stores, where pollutants are stored, for energy. Because the cubs are nursed on fat rich milk, the cubs are exposed to very high pollution loads from their mother.
Oil development in the Arctic poses a wide range of threats to polar bears ranging from oil spills to increased human-bear interactions. It is probable that an oil spill in sea ice habitat would result in oil being concentrated in leads and between ice floes resulting in both polar bears and their main prey (ringed and bearded seals) being directly exposed to oil. Another concern is that seals covered in oil may be a major source of oil to polar bears. Other studies suggest that polar bears are sensitive to disturbance at maternity den sites. Disturbance could occur both when a pregnant female is selecting a den site and during the winter-spring after the cubs are born. If exploration or development occurred sufficiently close to a den, the mother may abandon the den prematurely or abandon her offspring.
Over-harvest is an ongoing concern for some polar bear populations: particularly in areas where there is no information on population size (e.g., Québec, east Greenland, and the Chukchi Sea) and no quotas. It is important that population estimates and projections are based on substantiated scientific data. An additional concern is that population inventory programs occur relatively infrequently in some areas so if the harvest rate is above the sustainable level, the population may be reduced before the next inventory is made. Recent development of co-management agreements and greater involvement of local people and hunters is improving the management of polar bears in some areas.
Pinxi, You’ve copied lots of words from activists with PhDs. But the bottom line is that polar bear numbers have increased dramatically over the last 30 years while the extent of sea ice has declined.
This would suggest that polar bear numbers are about as limited by the extent of sea ice as camel numbers are by the extent of the Australian desert.
Jen – your analysis is too simplistic and dismissive. The large ice mass is perhaps an omen of a system under rapid change. One needs to look at not only population numbers but health.
And I wonder how well we really know bear populations. On what basis of certainty? If so is your zoological expertise certain enough to guarantee these trends?
This very detailed and recent paper portrays a worrisome trend.
Polar Bear Population Status in the Southern Beaufort Sea
By Eric V. Regehr1, Steven C. Amstrup1, and Ian Stirling2
http://pubs.usgs.gov/of/2006/1337/pdf/ofr20061337.pdf
ABSTRACT:
Polar bears depend entirely on sea ice for survival. In recent years, a warming climate has caused major changes in the Arctic sea ice environment, leading to concerns regarding the status of polar bear populations. Here we present findings from long-term studies of polar bears in the southern Beaufort Sea (SBS) region of the U.S. and Canada, which are relevant to these concerns. We applied open population capture-recapture models to data collected from 2001 to 2006, and estimated there were 1,526 (95% CI = 1,211; 1,841) polar bears in the SBS region in 2006. The number of polar bears in this region was previously estimated to be approximately 1,800. Because precision of earlier estimates was low, our current estimate of population size and the earlier ones cannot be statistically differentiated. For the 2001–06 period, the best fitting capture-recapture model provided estimates of total apparent survival of 0.43 for cubs of the year (COYs), and 0.92 for all polar bears older than COYs. Because the survival rates for older polar bears included multiple sex and age strata, they could not be compared to previous estimates. Survival rates for COYs, however, were significantly lower than estimates derived in earlier studies (P = 0.03). The lower survival of COYs was corroborated by a comparison of the number of COYs per adult female for periods before (1967–89) and after (1990–2006) the winter of 1989–90, when warming temperatures and altered atmospheric circulation caused an abrupt change in sea ice conditions in the Arctic basin. In the latter period, there were significantly more COYs per adult female in the spring (P = 0.02), and significantly fewer COYs per adult female in the autumn (P < 0.001). Apparently, cub production was higher in the latter period, but fewer cubs survived beyond the first 6 months of life. Parallel with declining survival, skull measurements suggested that COYs captured from 1990 to 2006 were smaller than those captured before 1990. Similarly, both skull measurements and body weights suggested that adult males captured from 1990 to 2006 were smaller than those captured before 1990. The smaller stature of males was especially notable because it corresponded with a higher mean age of adult males. Male polar bears continue to grow into their teens, and if adequately nourished, the older males captured in the latter period should have been larger than those captured earlier. In western Hudson Bay, Canada, a significant decline in population size was preceded by observed declines in cub survival and physical stature. The evidence of declining recruitment and body size reported here, therefore, suggests vigilance regarding the future of polar bears in the SBS region.
And talking about animals in zoos is utterly silly – of course the bears might survive very well not having to find food, having their private swimming pool and protected from hot days with ice baths with watermelon etc. See how long a polar bear lasts wandering around a dry eucalypt woodland on a hot week in January down the Gold Coast hinterland. Depends on how many residents snacked I guess.
Anyway – I suggest caution and further monitoring is required. I wouldn’t put money on it.
Jennifer what EVIDENCE do you have that the continued decline of sea ice will not eventually extirpate the polar bear populations? Do you think they’ll levitate & snatch albatross from the skies?
So what if the bear numbers have recently moved back toward carrying capacity after excessive culling ended, how you can extrapolate on that basis? How does that support a claim that disappearing ice, ie disapparing habitat, won’t reach a critical point that can no longer support a viable polar bear population? You’re really trying to jam a square peg in a round hole with that shameful argument.
Assuming they can adapt to live off ice, why are they currently restricted to ice and do you think they’ll adapt more quickly than the ice is disappearing? You’re ignoring all of these factors. Would you be content if the only surviving bears are in zoos? If you start looking for EVIDENCE, you might find that 2 most studied species of polar bear have declining numbers.
“activists with PhDs”
yeah I bet they found those PhD’s in their organic weeties packet. Thank our stars that not all PhD holders can willingly lobby and mislead the public by ignoring the inconvenient science like you can.
Indeed it’s probably even reasonable to surmise that early warming breaks up ice packs moderately and facilitates hunting more opportunities. Balanced against this is further advanced warming when the gaps between ice floes increase and energy expenditure in terms of swimming between floes increases.
Same issue with salinity – be interesting to observe the salinity trend when wetter seasons return.
Ain’t over till it’s over (or the fat lady sings).
Of course with all these issues – climate change and salinity – we’ve gone past scientific discussion into politics, public perception and media. It’s very hard to do these discussions precisely and thoughtfully.
Most relevantly if you were doing policy analysis for Dirk Kempthorne what would you recommend for future action in caring for the long needs of this iconic species (as a highly professional and rational policy officer) ?
In the short-term it may host the bears. But gee let’s be glad that the IUCN looks beyond next year’s sponsored lunch
Hi Jennifer,
Basically can’t see the problem using polar bears as a messenger regarding global warming.
Actually the threat is kind of acute…
I have been out for some hours this morning…I live on the same latitude as southern Greenland, and what do I hear… the birds are singing spring songs in the middle of the winter!!! This is really scary….
I have heard from ornithologists that larks and other migratory birds have arrived to Northern Finland…and the real winter has not yet arrived.
Something terribly wrong is happening now with the climate …and it is not unvisible or something that you read about in the papers…
Regarding threats to polar bears , they are as well threatened by contaminants( we have discussed this previously).
But much of the public’s attention is focused on polar bears…but let’s not forget the other species as well…
Pinxi,
The available evidence suggests that polar bears numbers are not influenced by sea ice extent.
The “activists with PhDs” have made all sorts of outrageous assumptions to claim global warming will result in the extinction of polar bears.
I can’t provide you with evidence to support any of their claims about what might happen in the future and I am not making any claims about the future except that more southern populations of polar bears have the option of moving further north.
In contrast you have made many claims including that the extent of sea ice will continue to decline and that there is “less food”. I am particularly interested in any data that you may have which would indicate that numbers of seals etcetera are in generally in decline in the artic?
And how do bears hunt seals?
How much can a polar …bear?
Jennifer,
Hope you don’t mind !
http://charlesandroger.ca/movie_b.htm
Luke, It depends which species of seal. They rip the fat from under the skin of ring seals and chuck away the rest.
The only threat to offshore oil installations are environmentalists.
Nature we have worked out how to handle but the stupidity of Greenies continue to surprise us.
During the MWP, crops were grown in southern Greenland, which supported a population of around 2,000 people, and the arctic was largely free of sea ice. The remains of those settlements are now mostly under ice or perma frost. Polar bears survived then, and during the following LIA, were seen as far south as the Orkney Islands.
It’s interesting that the largest measured chunk of ice that broke away from antarctica, was 200km long by 60km wide, larger then this one; and that was in 1956. Further, during Captain Cook’s antarctic voyage in 1772, he sailed around an iceberg, which according to his logging was about half the size of Tasmania. All long before ‘global warming’ alarmism.
Sid:” the arctic was largely free of sea ice. ”
No Sid, that is not correct…
I have learned in school all those Greenland sagas and the Viking settlements .
According to the sagas only southern Greenland was suitable to live in for the Vikings… in northern parts of Greenland as well as in Canada it was all permafrost.
” maybe George can read it and report back re the oil installations???”
Basically they say that when the winter ice melts, it may float free and threaten oil platforms and shipping in the Beaufort sea .. or words to that effect ….
😉
Jen – I mean – how do they hunt them. Chasing them from a distance or stalking near an air-hole in the ice. So seal population is not necessarily an indicator of food availability. It’s a terrain x seal population interaction.
Fascinating that we’re all interested in sketchy folklore from the MWP and LIA yet uninterested in any quantitative modern day information.
Let’s take 2 bits of info:
a) Ice area has reduced.
b) total polar bear numbers have increased.
and argue “The available evidence suggests that polar bears numbers are not influenced by sea ice extent.”
Where is that evidence?
What sources of ‘available evidence’ did you assess? Surely the IPA pays you to do considered work, not just take a deliberately narrow view. You ignore all other contributing factors to b) and refuse to acknowledge that if trends continue, eventually a) will limit and then reverse b).
What other scientific body can verify this claim? What scientific evidence backs this claim and how did you isolate this direct connection from the effects of reduced human take? What is the carrying capacity of the current ice area? What is the minimum ice area that can sustain a minimum viable polar bear population, considering its need for habitat and continued sources of food?
“claims including that the extent of sea ice will continue to decline”. Actually panels of proper scientists have made that claim. What evidence do you have to the contrary? Do you want to present an anti-GW case now? You’re the self-proclaiming evidence-based scientist writing about how the polar bears are adaptable and probably benefiting from the ice break up yetta yarty lobbyist blartha so surely you’ve done your homework.
I’m keen to learn how to present evidence-based science. Are you applying best practice here Jennifer? Please treat this as an opportunity to show evidence-based science should be done.
Jennifer refer Luke’s question: what would you recommend for future action in caring for the long needs of this iconic species (as a highly professional and rational policy officer)?
Pinxi,
You are ignoring the evidence that I have presented on polar bears. Also, I’m on hols from the IPA for three weeks and what I write at this blog has never been sponsored by the IPA. But I guess you keep throwing in “IPA” as a diversion?
And as regards your last comment … there are much higher priorities than polar bears and global warming. So as a “rational policy officer” I would be worrying about other animal species including freshwater dolphins and porpoises, northern hairy nosed wombats.
In short, the preoccupation with “gobal warming and polar bears” is fiddling while Rome burns … so to speak.
Luke,
What exactly are you getting at? Could it be that you want me to ‘acknowledge’ for you that because ring seals live on sea ice and some polar bears eat ring seals then a decline in the extent of sea ice will automoatically lead to the extinction of polar bears? And I thought you understood that natural systems are often a bit more complicated than that!
What evidence is that Jennifer? What sources?
IPA: You wrote on the polar bears for the IPA glossy magazine. You’ve referenced that above. Hence it’s reasonable to expect that you evidence for your claims.
You must have a good bloody cache of evidence for you disagree with expert scientists who are familiar with the conditions and system factors affecting the polar bears.
If it’s not a worry for you, why keep writing about it? If it’s not a worry for you then we can be confident that you’ve done SFA research which explains why you’re not providing ANY evidence, no causal relationships at all, to support your silly claims.
You just want to throw fire on GW concerns. I guess that might answer our question about where the IPA partyline on GW would head next. Revert to stronger denial.
“And I thought you understood that natural systems are often a bit more complicated than that!
OH SWEET JESUS!! We’ve been trying to tell you that Jennifer. This is why we’re so incredulous about your unsubstantiated narrow interpretation of a few pieces of information that you can’t establish a connection between.
Pinxi,
This thread has nothing to do with the IPA.
Now, I presented the following evidence in the original post which suggests that the extent of sea ice does not determine polar bear numbers:
“While the area of sea ice has been declining over the last couple of decades, the number of polar bears has actually been increasing. That’s right increasing!
So it is very wrong for the Australian Broadcasting Corporation to uncritically report that: “The World Wide Fund for Nature says the declining number of polar bears is a major warning on the impact of climate change.”
There were only about 5,000 polar bears in 1970, numbers depressed by hunting. There are now about 25,000 polar bears. The increase a consequence of agreements to restrict hunting under quota systems.
The biggest threat to discrete populations of polar bears continues to be illegal hunting in places like the Chukchi sea and Greenland’s failure to agree to the quota system.
If the extent of sea ice continues to decline in places like Hudson Bay and the Beaufort Sea, these populations of polar bears can move north to where there is more sea ice with ringed seals, or they might simply switch to hunting seals that prefer warmer weather.”
Your problem Pinxi, if I may be so bold as to suggest that you have a problem, is that you believe ‘experts’ and you appear to have no understanding of what is meant by the word ‘evidence’. 🙂
Jen – in between the shelling (and don’t let me distract you as it’s good getting you in an interaction) .. ..
(1) How does the terrain affect the bears hunting ability – I’m asking what we know. If bears find it hard to hunt seals in the open then the hunting environment is as important as the prey desnity. Apparently they know to hide their noses for example – a fascinating account at:
http://www.ursusinternational.org/factspolar.htm
(2) no response on the actual science from the zoologists I have tabled ?
I’d be a fool to believe unsubstantiated lobbyist claims instead.
Jennifer wrote: Now, I presented the following evidence in the original post which suggests that the extent of sea ice does not determine polar bear numbers:
“While the area of sea ice has been declining over the last couple of decades, the number of polar bears has actually been increasing. That’s right increasing!
Where’s the evidence in that for your claim? What’s the connection and how did you establish it?
you have 2 pieces of information:
1. area of sea ice has been declining over the last couple of decades
2. the number of polar bears has actually been increasing.
what is the relationship between 1 and 2 and how did you establish it?
What evidence do you have that the ice won’t continue to decrease in area until it’s too small to support a polar bear population?
What systems factors have you considered in reaching your conclusion?
Why do you know better than the experts who in their articles have long lists of references?
And I thought you understood that natural systems are often a bit more complicated than that!
Evidence-based science.
And I thought you understood that natural systems are often a bit more complicated than that!
Evidence-based science.
And I thought you understood that natural systems are often a bit more complicated than that!
Evidence-based science.
And I thought you understood that natural systems are often a bit more complicated than that!
Evidence-based science.
And I thought you understood that natural systems are often a bit more complicated than that!
Evidence-based science.
And I thought you understood that natural systems are often a bit more complicated than that!
Evidence-based science.
And I thought you understood that natural systems are often a bit more complicated than that!
Evidence-based science.
And I thought you understood that natural systems are often a bit more complicated than that!
Evidence-based science.
Polar Bear Population Status in the Southern Beaufort Sea
By Eric V. Regehr1, Steven C. Amstrup1, and Ian Stirling2
“Polar bears depend entirely on sea ice for survival.”
Jennifer-my-middle-name-is-evidence what evidence do you have to the contrary?
And that was “rational policy officer” for the Arctic wilderness not the domain of the Hairy Nosed Wombat.
Presumably you’d brief then “the polar bears are absolutely fine and there are no significant threatening processes – recommend against any listing of endangerment or special research funding”.
Luke,
1. Polar bears hunt lots of different things including ring seals. What do you mean, hard to hunt in the open? And I’m not claiming to be an expert on polar bears … just that there is no correlation between bear numbers and the extent of sea ice despite the many claims.
2. And sorry, what ‘science’ from which zoologists?
Pinxi,
Why do you read this blog … given you consider me nothing more than a lobbyist? That’s it. I’ve no idea who you are, and you have no respect for me… conversation over. Cheers,
PS There are two bits of evidence that I thought we agreed on:
1. polar bear numbers have increased over the last 30 years.
2. the extent of sea ice has decreased over the last 30 yeras.
that’s my evidence.
i’m unsure what evidence you have presented so far.
Artic weather forecast:
http://members.tripod.com/~JB5353/gmvn/weather.wav
ummm .. .. ..
http://pubs.usgs.gov/of/2006/1337/pdf/ofr20061337.pdf
Yes it was mind-numbingly familiar & repetitive:
– You being asked for the evidence to support your claim.
– You providing none.
Pinxi,
I’m trying to be polite, even though you continue to insult me.
Now, just to repeat:
I presented two bits of evidence 1. polar bear numbers have been increasing and 2. sea ice extent has been decreasing.
Now which bits of evidence did you present?
And do you agree about 1. and 2.?
Luke,
That link is to a paper that says the Beaufort population might be a bit thinner, but no decline in population numbers. You will have to summarize which bits of the paper you think provide evidence to suggest there is a link between global warming and polar bear numbers. It infers as much, and quotes an unpublished paper in support of the contention.
Hey, got to move beyond the abstract and look for the evidence!
Pinxi – be nice. We’re having a good chat.
Jen – I’m suggesting polar bears are primarily terrain dependent ambush predators – and otherwise oppoortunistic scavengers
Jennifer: “no correlation between bear numbers and the extent of sea ice despite the many claims”
“If the extent of sea ice continues to decline in places like Hudson Bay and the Beaufort Sea, these populations of polar bears can move north”
http://pubs.usgs.gov/of/2006/1337/pdf/ofr20061337.pdf
“The relationship between decreased availability of sea ice and declining population size in western Hudson Bay, which is near the southern extreme of polar bear range, is cause for concern regarding the future status of polar bears in more northern regions such as the SBS.”
Cause for concern is my concern.
Luke,
You might be right.
And I’m suggesting that there is lots of sea ice and lots of ring seals relative to polar bears. In particular, I’m suggeting that polar bear population numbers have been depressed by hunting and are not limited by numbers of ring seals … and may never be.
Pinxi,
‘Cause for concern’ is not evidence.
OK let’s review the conclusion (out of an intimidatingly statitical paper showing the difficulty of working with these species)
Information on changes in survival and physical stature, reported here, indicate that the status of polar bears in the SBS region is changing. Annual survival rates of COYs estimated from the 2001 to 2006 capture-recapture study were lower than survival rates estimated in previous studies. The increased loss of cubs during the first 6 months of life may be associated with the smaller physical stature of COYs observed in recent years. The smaller physical stature of COYs was paralleled by a smaller physical stature of adult males, even though the average age of adult males has increased. Despite these indicators of a declining status for the SBS polar bear population, our best estimate of the current size of the population does not show a statistically significant decline. This may mean there has been no change in numbers in recent years, or it could reflect insufficient precision in current and past estimates to resolve such a change.
Although our 2001–06 capture-recapture study did not provide evidence for a change in the size of the SBS polar bear population, significant changes in cub survival and physical stature must ultimately have population level effects. Lowered body weight has been implicated in declining survival of polar bear cubs in western Hudson Bay, Canada. There, reduced cub survival, associated with declines in physical stature caused by reduced foraging opportunity, was recorded long before a statistically significant decline in population size was confirmed. The relationship between decreased availability of sea ice and declining population size in western Hudson Bay, which is near the southern extreme of polar bear range, is cause for concern regarding the future status of polar bears in more northern regions such as the SBS. Because more profound declines in sea ice area and extent are predicted for these northern regions, continued monitoring and conservative management of the SBS polar bear population is warranted.”
SO we have lower cub survival, lower body weights, older adults – implicated previously in population decline.
So as nominated policy officer on this watch, given you were on recreation leave, I would:
(a) brief for more monitoring, population and health surveys
(b) ask for a Cabinet brief on the state of knowledge from the zoologists, ecologists and climatologists
(c) attempt to get a transpolar program going with other nations around the Artic circle.
(d) get a “greenie-stabilising” press release out on what we know and don’t know.
I wouldn’t be saying “nah 100% b/s – have another beer”
As I have said on a number of comments lately with climate change – it’s hard to get the message exactly right. It’s important in beating off the stupid levels of skepticism that we don’t overstate the science position on AGW and do it “correctly and un-emotionally”. Having to argue the position up in a hostile US and Australian political environment risks scientists of overstating the position in an attempt to beat down the general crappiness of the contrarian position.
See this excellent compare and contrast on over-sell:
http://scienceblogs.com/deltoid/2006/12/agw_oversold_or_not.php
Similarly – wouldn’t be too dismissive on the health of those dang baaars!
They did real research, looking for real evidence!, in the exact areas that you mentioned earlier and they found “Polar bears depend entirely on sea ice for survival” and a “relationship between decreased availability of sea ice and declining population size”.
On your PS Jennifer:
There are two bits of evidence that I thought we agreed on:
1. polar bear numbers have increased over the last 30 years.
2. the extent of sea ice has decreased over the last 30 yeras.
that’s my evidence.
What’s the correlation between the 2? How did you establish this?
Pinxi,
The popular press has suggested that polar bear numbers are decreasing because the extent of sea ice is decreasing.
I’ve stating that there is no correlation. I’m stating that polar bear numbers are actually increasing. My evidence suggests that the popular perception that there is a correlation is wrong.
You are now misrepresenting my position.
I’m off to bed. See ya.
Capt´n Pugwash & Lukeylook,
Polar bears in the Svalbard area – Pop. increased from 1000 to 3000 or so … gimme a few swipes of an Isbjorn´s paw and I´ll dig up a reference … and this is despite them being one of the most polluted animals in the arctic … go figure
” Polar bears have now for the first time been listed as “Vulnerable”, one of three “threatened”-categories on the IUCN Red List of Threatened Species” ( 2006 )
We can now await the imminent Arrival of the Arctic Sunrise and hordes of NGO´s in suspenders … ( see luke – haven´t forgotten 😉 )
Luke,
In your own words what did they discover about the population numbers of those polar bears?
My conclusion from the paper is that: They discovered that there was no decline in the population numbers of the Beaufort Sea population.
See ya.
You’ve gone beyond that Jennifer as you generally portray a rosy, unthreatened future for polar bears who are unaffected by the extent of ice in your view. You wrote that ice shelves breaking up is good for polar bears, and “the whole “disappearing sea ice threatens polar bear’s survival” story is in reality a farce” and they can just move north and live happily ever after or move to my local zoo. And in the IPA article that you linked above you wrote “polar bears may be disadvantaged by global warming, but they are unlikely to become extinct.”
hence I’ve been asking for evidence why you claim that polar bear numbers are not and will not be adversely affected by declining ice or global warming. In reply you’ve pointed to 2 pieces of data but you haven’t explained any connection between them. Hence your claims remain unsubstantiated and go against the reports by scientists who actually work in this field.
Minor conclusion Jen and that’s the way we want to keep it.
But the health of them thar baaaars is not up to spec.
And that’s what has preceded previous declines AS THEY SAID. They also said population estimation is quite difficult. In any region undergoing major change we should be circumspect and observant as to what may happen next. Let’s not be cavalier in our quest to kick Greenpeace in the groin. Did someone say “GREENPEACE”.
Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Greenpeace. Sea Shepherd.
George you animal – have you slipped into a little plastic jumpsuit for New Years perhaps covered in whale oil.
Jennifer, do you have any idea how evolution works? Species are adapted to a specialty. The polar bear being an excellent example, they live on sea ice, no other species of bear does. They can’t compete in other environments, the specialisation they have won’t match what their competitors will have. If they tried to move into forests and live there, the other bears will have too many advantages.
So peskii whats all this blather about lack of evidence?
“Conclusion
Using old temperature observations from early observers, the existing Greenland temperature records have been extended back to the year 1784. Gaps remain, mostly during summer and autumn. In the process of creating the long record, a few inhomogeneities were identified and corrected. Most of the homogeneity problems were due to changes in the hours at which temperature observations were carried out.
Comparison against winter season ice core proxy data showed stable and highly significant correlations throughout the period covered by the extended Greenland temperature series. This marked consistency, r = 0.67/0.60 for the extended/existing data, shows that both the ice core data and the extended temperature series are very robust.
The warmest year in the extended Greenland temperature record is 1941, while the 1930s and 1940s are the warmest decades. Two distinct cold periods, following the 1809 (‘‘unidentified’’ volcanic eruption and the eruption of Tambora in 1815 make the 1810s the coldest decade on record.”
http://www.cru.uea.ac.uk/cru/data/greenland/vintheretal2006.pdf
ST,
Polar bears also live on land in the arctic 😉 and don´t really have any other competitors other than us
and not to trivialise anything – but those animals that specialise too much will die off with most large environmental changes, be it man made or not… Adapt or die as the theory goes.. what part we have in it is another story / discussion..
Lukeylook .. C´mon lukey – you know I like my black jumpsuits natural .. leather preferably (or fur at a push baby ) 😉
Science on where we’re going is pretty dire.
Arctic System on Trajectory to New, Seasonally Ice-Free State
Overpeck, Jonathan T.; Sturm, Matthew; Francis, Jennifer A.; Perovich, Donald K.; Serreze, Mark C.; Benner, Ronald; Carmack, Eddy C.; Chapin, Stuart, III; Gerlach, S. Craig; Hamilton, Lawrence C.; Hinzman, Larry D.; Holland, Marika; Huntington, Henry P.; Key, Jeffrey R.; Lloyd, Andrea H.; MacDonald, Glen M.; McFadden, Joe; Noone, David; Prowse, Terry D.; Schlosser, Peter; Vörösmarty, Charles
The Arctic system is moving toward a new state that falls outside the envelope of glacial-interglacialfluctuations that prevailed during recent Earth history. This future Arctic is likely to have dramatically less permanent ice than exists at present. At the present rate of change, a summer ice-free Arctic Ocean within a century is a real possibility, a state not witnessed for at least a million years. The change appears to be driven largely by feedback-enhanced global climate warming, and there seem to be few, if any, processes or feedbacks within the Arctic system that are capable of altering the trajectory toward this “super interglacial” state. For nearly 30 years, Arctic sea ice extent [e.g., Stroeve et al., 2005] and thickness [ Rothrock et al., 2003] have been falling dramatically (Figure 1). Permafrost temperatures are rising and coverage is decreasing [Osterkamp and Romanovsky, 1999]. Mountain glaciers and the Greenland ice sheet are shrinking [Meier et al., 2003; Box et al., 2004]. Evidence suggests we are witnessing the early stage of an anthropogenically induced global warming superimposed on natural cycles [Intergovernmental Panel on Climate Change, 2001], reinforced by reductions in Arctic ice.
http://www.faculty.uaf.edu/fffsc/Chapin%20papers/OverpecketalEOS05.pdf
exactly George, ST was pointing out they don’t have to compete & they’re specialised … because Jennifer has simply suggested they just adapt & move, without considering if that involves competition, different types of food, different patterns of predation/scavenging or whether the polar bears could adapt quickly enough, esp where there are human pressures too. yes George you did trivialise it, you can’t exclude man from the system. They could evolve backwards and then we’d have, errm, more brown bears.
what is the popular press reporting?
Five of the Arctic’s 19 polar bear populations are on the decline, the World Conservation Union’s Polar Bear Specialist Group says.
All of the troubled populations are located in Canada, says the group, which includes Canadian polar bear scientists and international researchers.
The group says the western Hudson Bay’s polar bear population has dropped by 22 per cent and the southern Beaufort Sea’s by 17 per cent.
http://www.cbc.ca/canada/north/story/2006/12/18/bear-count.html
this link is essential reading
http://www.timesonline.co.uk/article/0,,2087-1938132,00.html
SCIENTISTS have for the first time found evidence that polar bears are drowning because climate change is melting the Arctic ice shelf.
The researchers were startled to find bears having to swim up to 60 miles across open sea to find food. They are being forced into the long voyages because the ice floes from which they feed are melting, becoming smaller and drifting farther apart.
Although polar bears are strong swimmers, they are adapted for swimming close to the shore. Their sea journeys leave them them vulnerable to exhaustion, hypothermia or being swamped by waves.
DIRK KEMPTHORNE: When the Fish and Wildlife Service went through the process of the Endangered Species Act, they’re required to look at five different factors. And there was only one factor, and that was the habitat, that is being diminished, and that is because of melting sea ice.
They specifically looked at a variety of other things — for example, the harvest of the polar bear by native Alaskans. That was not a threat. They looked at oil and gas, energy development in the North Slope in Alaska. That was not a threat. It is one single issue, and that is melting ice, acknowledging that that trend is now taking place.
DIRK KEMPTHORNE: It is. There is a — what they have done — in a region which they call the western Hudson Bay in Canada, they’ve seen a decline of that particular population. One of the precursors to that decline was the actual weight loss and reduction of the size of the adult polar bears, and then the survival rate of the cubs, where we’re not having successful survival. That same precursor is being seen now in one of the populations in Alaska. But the Alaska population currently is stable, so that’s noted. But that’s all of this that has to be included into this modeling that has to take place.
http://www.pbs.org/newshour/bb/environment/july-dec06/bear_12-27.html
exactly George, ST was pointing out they don’t have to compete & they’re specialised … because Jennifer has simply suggested they just adapt & move, without considering if that involves competition, different types of food, different patterns of predation/scavenging or whether the polar bears could adapt quickly enough, esp where there are human pressures too. yes George you did trivialise it, you can’t exclude man from the system. They could evolve backwards and then we’d have, errm, more brown bears.
what is the popular press reporting?
Five of the Arctic’s 19 polar bear populations are on the decline, the World Conservation Union’s Polar Bear Specialist Group says.
All of the troubled populations are located in Canada, says the group, which includes Canadian polar bear scientists and international researchers.
The group says the western Hudson Bay’s polar bear population has dropped by 22 per cent and the southern Beaufort Sea’s by 17 per cent.
http://www.cbc.ca/canada/north/story/2006/12/18/bear-count.html
this link is essential reading
http://www.timesonline.co.uk/article/0,,2087-1938132,00.html
SCIENTISTS have for the first time found evidence that polar bears are drowning because climate change is melting the Arctic ice shelf.
The researchers were startled to find bears having to swim up to 60 miles across open sea to find food. They are being forced into the long voyages because the ice floes from which they feed are melting, becoming smaller and drifting farther apart.
Although polar bears are strong swimmers, they are adapted for swimming close to the shore. Their sea journeys leave them them vulnerable to exhaustion, hypothermia or being swamped by waves.
DIRK KEMPTHORNE: When the Fish and Wildlife Service went through the process of the Endangered Species Act, they’re required to look at five different factors. And there was only one factor, and that was the habitat, that is being diminished, and that is because of melting sea ice.
They specifically looked at a variety of other things — for example, the harvest of the polar bear by native Alaskans. That was not a threat. They looked at oil and gas, energy development in the North Slope in Alaska. That was not a threat. It is one single issue, and that is melting ice, acknowledging that that trend is now taking place.
DIRK KEMPTHORNE: It is. There is a — what they have done — in a region which they call the western Hudson Bay in Canada, they’ve seen a decline of that particular population. One of the precursors to that decline was the actual weight loss and reduction of the size of the adult polar bears, and then the survival rate of the cubs, where we’re not having successful survival. That same precursor is being seen now in one of the populations in Alaska. But the Alaska population currently is stable, so that’s noted. But that’s all of this that has to be included into this modeling that has to take place.
http://www.pbs.org/newshour/bb/environment/july-dec06/bear_12-27.html
Capt´n Puggy,
“yes George you did trivialise it, you can’t exclude man from the system. They could evolve backwards and then we’d have, errm, more brown bears. ”
Oooh … but if we can´t exclude man from the system then we´re just another competitor in the animal kingdom or?
Lemme trivialise it a wee bit more ..
adapt or die – one size fits all ..
RE yer post above Puggy – how does the eastern population data ( Barents sea and spitsbergen / Franz josef land etc a serious chunk of the total world pop ) fit into the theory? ( seriously )
Any choice links for the readership? found a few but nothing of substance – too busy oiling up my wee black number for lukey
A few comments from a resident of Polar Bear country, If I may:
First of all, this case has NOTHING to do with AGW.
This is about restricting the import of Polar Bear hides into the US by American trophy hunters who make up the bulk of trophy hunters taking bears in Canada.
If the bears get listed, the hides are inadmissable and then the hunters go elsewhere.
The animal protest industry always has Inuit economic use of animal resources in its sights and who can resist hopping on board a wagon to “save the Polar Bears”?
Note how the Bush administration after their settlement with the plaintives, has said that they do NOT recognise that the bears are threatened by AGW but simply by GW and a consequently melting arctic.
The press keep reporting the Greenpeace and co. mantra that listing will mean that all the stops will have to be pulled out to stop any activities that might threaten the bears – conveniently, this doesn’t include mere trifles suchas oil drilling in the region.
Greenpeace and co keep harping on about two populations that have shown a small and recent decline. These populations were over exploited between population counts. The decline was noticed and a moratorium on harvesting from those populations was put in place.
The world class management systems in place for the bears worked and continue to work.
Most other populations are stable or on the increase.
There are more bears now than even a mere ten years ago.
One population near to where I live has gone from 900 to 1500 bears during this period.
Polar Bears regularly swim huge distances in open water. A year ago, I saw a chart plotting the routes of radio-tagged bears between here (Baffin Island) and Greenland. There is not an inch of the Davis Straits these bears don’t swim!
The reports of bears drowning seems far-fetched to me. This is very much a case of suposition being reported as fact.
Skinny bears, canibalism, bears closer to communities etc are all also known to be signs of overpopulation which jibes with what a number of Inuit elders have been saying for years.
If this listing goes ahead (which it almost certainly will and for all the wrong reasons) this will mean a loss of $3-4 million dollars to the Nunavut economy. Most of which goes directly to the Inuit hunters & guides and their families in some of the remotest communities in the Arctic. These guides are some of the poorest people in the north and are still reeeling from the MMPA and EU restrictions on sealskins (another entirely sustainable harvest that didn’t require extra “protections”) which decimated the traditional economy, led to heaps of suicides and made it harder for hunters to afford the costs of hunting and providing their families and communities with high value nutritious fare like seals, caribou, fish, whales, ducks, geese, clams, berries, seaweed etc.
When families can’t get highly nutritious “country foods” they are forced to resort to industrial processed fare.
The ramifications, predictably, are increased rates of diabetes, heart disease etc all of which we are now seeing.
Polar Bear sports hunts directly underwrite the Inuit food economy and I really don’t know where we might make up the shortfall.
As always, conservation is a fight between powerful parties and based on western middle class aesthetic prejudices.
The people who actually live among the species in question are the last to be heard.
IceClass wrote:
“When families can’t get highly nutritious “country foods” they are forced to resort to industrial processed fare. The ramifications, predictably, are increased rates of diabetes, heart disease etc all of which we are now seeing.”
George wrote:
“adapt or die – one size fits all ..”
Jennifer wrote:
“the two polar bears living happily at Sea World, on Queensland’s Gold Coast, enjoying watermelons and museli bars, are evidence of the capacity of this big bear to adapt, including to warm weather.”
I am assuming the assessment that these bears are happy is yours Jennifer. Or perhaps Sea World has commissioned an “activist with a PhD” to do a study on the bears and come up with this conclusion. The bears are in a climate-controlled environment and do not just eat muesli bars and watermelons (the long-term nutritional value of which- do we know?). These bears are not the same animals that have been in this enclosure since it opened.
The above piece by Pinxi is in the paper “Observations of mortality associated with extended open-water swimming by polar bears in the Alaskan Beaufort Sea” by Monett and Leason , in Polar Biology 2006.
Stirling and Parkinson write that the five pops of polar bears in the Canadian Arctic (including 2 shared with Greenland) are likely to significantly decline in numbers if trends continue. From “Possible effects of climate warming on selected populations of polar bears (Ursus maritimus) in the Canadian Arctic (2006) Arctic. I am sure Ian Stirling would love to be called an activist with a PhD.
WWF, Greenpeace and similar NGO’s get their funding from ‘comfy middle classers’, by promoting alarmist stories about such things as ‘global warming’and it’s associated threat to Polar Bears. These campaigns so capture the imagination, that facts don’t matter. The ‘scientific experts’ quickly hop onto the gravy train that these NGO’s provide. The more alarmism the more need for ‘scientific research’, so forget about truth!
A typical example of the above, was the Crown of Thorns Starfish, (remember) that was going to decimate the GBR within 10 years. Didn’t the NGO’s and their scientist supporters have a field day there.
Thanks IceClass your posting shows that Jennifers assessment on the bears population was correct.
Further, you show yet again that these NGO’s have no regard for the welfare of communities such as your own.
Hello all,
George ” The polar bear population in Spitzbergen/Svalbard has increased from 1000 to 3000…,go figure”
Guess one of the reasons is the hunting ban…
Re contaminants…probably their impact will be shown in the near future
So what do researchers and people say in Polar Bear country up in Svalbard?
The world’s most northern paper Svalbardposten makes these statements ( 28.12.2006):
” The Bush administration wants to list the polar bear as threatened with extinction. The background to this decision is based upon the Sternreport.
This report indicates that the Arctic will be free from sea ice in 2040.
This melting of ice and climate change will make the living conditions hard for the polar bears, which are heavily dependant on ice for survival.
Norwegian scientist, Jon Aars, polar bear researcher on Norwegian Polar Institution, states ” it is highly possible that the polar bear population will have a heavy decline , since the ice cover will decrease.”
The ice conditions will make it very difficult for the polar bear to carry out hunting, it will simply die from starvation.
Another article from Svalbardposten ( 8.12.2006)
( This is a most scary one).
” The poor sea ice conditions will probably have the consequences that no polar bear cubs will be born this season on Hopet ( Svalbard).
Norwegian link to the articles:
http://www.svalbardposten.no/nyhet.cfm?nyhetid=522
Trying to find out what the other 14/19 PB populations are doing???
And what happened to PB’s during the 1940’s Arctic warming?
Jennifer?
Pinxi?
Iceclass are you inuit? Perhaps your people should get to the root of the problem by launching a (NGO-supported?) class action over the effects of climate-change against industrial activities of GHG-releasing countries.
Meanwhile, shorter-term economic losses ARE considered by the indigenous peoples-pro UN in the IUCN decisions but don’t by themselves change threats to bear populations. Reflect on the collapse of cod stocks in Newfoundland. Scientific warnings were ignored by the govinmint due to economic concerns over lost income until.. cod no more.
Uncritical believers like Sid will ensure that Jen’s overly simplified denialist arguments will continue to circulate to the detriment of constructive action to mitigate polar bear threats. Jen was invited to suggest constructive action but declined.
Yes it is all about money and vested interests in the end.
So it seems that as a result of getting additional income from hunting, the Inuit are consuming more western food from the shops.
How did the Inuit survive before well-heeled yanks trophy hunting turned up? Maybe they were healthier? Perhaps all this access to western consumer goods is actually ruining their health not improving it?
Given the money involved it would seem just as easy for government to compensate them for the lost income. And leave them to harvest their own quota for traditional purposes.
I enjoyed this press clipping. Makes you want to have open season on urologists.
http://www.nytimes.com/2006/05/27/world/americas/27bears.html?pagewanted=2&ei=5088&en=07809799811ff6cb&ex=1306382400&partner=rssnyt&emc=rss
I think you could make even more money with wildlife tours. This notion of ultra-rich sepos blowing animals away for mega-bucks is pretty rank IMHO. So if you get rich you’re allowed to compensate for your small dick and meaningless life with Disney thrills gained by blowing interesting fauna away in exotic locations. Wow – great values !
We also need a metric for separating “evidence based” from scum-bag “activists with PhDs on NGO gravy trains”.
“Hunters say few experiences can compare with the sensation of sighting a bear, then watching the Inuit guides release their huskies to surround and confuse the prey long enough for the hunters to shoot it.”
“This is my Disney World,”
“It’s tickling to think I could be the last American hunter who brings in a polar bear trophy,” he said.”
I doubt its a satisfying way to earn a living, to put up with fat wankers like that shooting their way around your traditional motherland while you hold the bear still for them so they can shoot it.
Some compromises:
replace shooting with hand-to-hand combat.
Or give the septic hunters virtual reality goggles so they can pretend shoot the bears. The game could have scalable special effects setting for your preferred level of violence, hollywood explosive effects etc. The take-home trophy would be a made in china stuffed bear.
sorry, hand-to-paw
Before ditching expert scientific assessments in favour of personal, isolated observations, it’s worth considering the following (as one eg of possible misinterpretation):
“Marine scientist George Rose is concerned to hear European fishermen challenging the warnings of scientists because they can still find plenty of cod.
This echoes the claims of trawlermen on the Grand Banks in the late 1980s, but it turned out that they were observing a phenomenon he calls “hyper-aggregation”, in which fish cluster in ever-greater densities when their environment is under pressure.
“If you look at the data on the catches-per-unit of the trawler fleet, the highest ever recorded in this fishery were in 1992, when the stocks were on the verge of collapse,” said Professor Rose.
“So if fishermen are still saying they can find concentrations, that’s good news for now, but it should give no reassurance that you couldn’t take those last bits of fish down and push the whole thing right over the edge.”
http://news.bbc.co.uk/2/hi/science/nature/2580733.stm
for the table on those catch trends see here http://www.cbc.ca/news/background/fishing/cod.html
Is there a moral? heed the scientific warnings?
This is probably not the right thread to do this but:
I WISH EVERYONE A HAPPY NEW YEAR!
And a special thanks to Jen who provides us with this free speech blog.
Bravo!
yah happy new year to you all and the polar bears and whales too
HAPPY NEW YEAR hey! but I’m still busy keeping watch on our shore line.
Anne
” This report indicates that the Arctic will be free from sea ice in 2040.” ( Stern Report )
Ok, so lets think about a few things – Whats going to happen to the Seals in such a scenario ?
Will they be wiped out? will they adapt and say pup on land masses instead? What will happen to Polar bears ? will they adapt? Perhaps be preying on such seal populations that adapt by pupping on land masses ?
you tell me .. Adapt or die in such a scenario or? ..
2040 – a mere 33 years from now .. that would indicate that even if we stopped all of the polluting / Global warming gases etc etc NOW … it would be unlikely to have enough of an effect to prevent this happening -or would it?
I´d add that I believe that we will be a bit more concerned with the problems that melting ice caps cause us than the problems they cause Polar bears and seals in 2040 – but I´m a cynic …
” ” The poor sea ice conditions will probably have the consequences that no polar bear cubs will be born this season on Hopet ( Svalbard).”
It´s Hopen BTW ;op … Question is, is this a one season anomality or part of a trend?
A story about Hopen – I was on a ship that visited Hopen ( actually we were hiding bad weather in the lee of the Island ) and a guy from the station came out in a wee boat to pick up a bunch of us for a visit to the station.. as the boat came into our side, the guy handed me a rope to tie him up and removed the hood of his foul weather gear and said ” Hi George, how´s it going ” – turns out it was a guy I had worked with in Andenes 7-8 years before … and I meet him again on that wind swept hunk of rock in a remote part the arctic … small world indeed
Hi George,
Re ringed seals I might believe they eventually can adapt since they have different pupping and molting patterns in different parts of the world(?).
Well, the isbjornarna will probably walk down to Longyearbyen if they starve…LOL! I
If they are lucky they will just have a tranquilizer dart , otherwise a old Maser rifle from WWII can be their destiny….
Re Hopen…. but the polar bears lost Hopet( the hope) in Hopen…
George , interesting story…
Need some time to think about your other questions!
Dear Jennifer,
Considering the scientific evidence presented to you above that contrasts with your rosy presentation that no worries mate the polar bears will be fine cos they haven’t gorn extinct yet, will you consider the following?
3. Acknowledge the deficiencies in your position – pretending your argument is self evidently correct and beyond doubt when it clearly isn’t is dishonest and arrogant.
George:” ” This report indicates that the Arctic will be free from sea ice in 2040.” ( Stern Report )
Ok, so lets think about a few things – Whats going to happen to the Seals in such a scenario ?
Will they be wiped out? will they adapt and say pup on land masses instead? What will happen to Polar bears ? will they adapt? Perhaps be preying on such seal populations that adapt by pupping on land masses ?
you tell me .. Adapt or die in such a scenario or? ..”
As I have computer problems, I must divide my comment in three posts….
IMO you should look first what happens to the whole eco-system in the ice free Arctic scenario.
And start from the bottom of food chain up to top predators…
Water temperature will be changed, amounts of crustaceans, krill and zooplankton will be changed. This affects the fish stocks that the seals are dependent on. Decreased fish stocks affect seal population, reproduction and finally the polar bears. Maybe they will all starve…
As you maybe read, the Norwegian Polar Institute has given highest priority to the issue , what happens to the polar bears that didn’t give birth to polar bear cubs this season due to poor sea ice conditions….
“What will happen to Polar bears ? ”
Jennifer stated that the polar bears in Canada just had to move northwards in case of starvation… they are so smart.
Some studies have indicated that polar bears might rather starve to death than migrate…
And some other field studied have shown us that polar bears like brown bears have a tendency to move near human settlements if there is a scarcity of food ( Canada). Not very good, polar bears are extremely dangerous…
George:” 2040 – a mere 33 years from now .. that would indicate that even if we stopped all of the polluting / Global warming gases etc etc NOW … it would be unlikely to have enough of an effect to prevent this happening -or would it?
I´d add that I believe that we will be a bit more concerned with the problems that melting ice caps cause us than the problems they cause Polar bears and seals in 2040 – but I´m a cynic …”
Hi George,
I see that you finally have moved into Lukeland… a territory that me too is unwilling to walk into….
Guess in the highly unlikely scenario that all greenhouse emissions today would be stopped , the temperature will increase despite this with about 2 or 3 degrees. Maybe Lukey can give you a correct reply???
Maybe many people are tired of the melting ice cap stories and simply adding some icon animals to the climate issue will make it more interesting???
Morn´anne
“Water temperature will be changed, amounts of crustaceans, krill and zooplankton will be changed. This affects the fish stocks that the seals are dependent on. Decreased fish stocks affect seal population, reproduction and finally the polar bears. Maybe they will all starve…”
Will warmer water Effect the fish stocks, krill and zooplankton negatively? If yes, How much of a temperature rise? for how long?
If no, food supply is not a problem or?
As I mentioned above, I doubt if seals and polar bears will be our main concern in such a dooom and gloom scenario..
”
Morning George!
Dunno, as far as I know there are winners and losers in this warming ocean’s trend. Some commercial fish is supposed to increase others not…
Taking Jennifer’s preferred Polar Bear habitat, Sea World, as a source of information on polar bear populations:
“Due to governmental regulations on hunting, the population has increased from an estimated 10,000 polar bears in 1968 (Stirling, 1988). ”
No mention of ice extent as causing that increase, just restrictions on hunting.
George:” If no, food supply is not a problem or?”
Firstly, the eco-system in the Arctic is extremely sensitive to slight changes in temperature.
In Svalbard, the marine mammals: polar bears , walross and harbour seal are all on the Red list, classified as vulnerable.
The polar bear population is threatened by poor ice conditions and the walross and harbour seal populations are threatened by low reproduction.
Personally, I’m not sure why the reproduction numbers are low. Possible reasons: habitat loss/contamination???
It seems that PCBs & DDT compromises immune system & then reproduction in the harbour seals.
Polar Bears in a Warming Climate
Lots of important reading here, eg:
Only rarely has a bear been reported to capture a ringed seal in open water (Furnell and Oolooyuk, 1980Go) so it is unlikely that hunting in ice-free water will compensate for loss of ice to provide access to ringed seals. Bearded seals, walrus, and occasionally harbour seals (Phoca vitulina) are captured by polar bears when hauled out on land but such opportunities tend to be quite local and learned by a limited number of individuals. It is unlikely that predation on these other species would completely compensate for loss of opportunities to hunt ringed seals in most areas. In some areas, such as southern Davis Strait and the Barents Sea, it appears that harp seals are an important component of the diet so it is likely that polar bears would continue to prey on them as long as there was ice in areas occupied by these seals.
Throughout their range, the distribution of polar bears is centred on areas of good hunting habitat so an initial response to a reduction in sea ice could be an increase in bear densities resulting in more competition for the available prey. Reduction in sea ice area may allow increased hunting efficiency by polar bears if seals are restricted to smaller areas of suitable habitat. Concentration of seals in fjords or areas with freshwater influx that may continue to freeze over for longer periods could create a concentrated food resource for polar bears. However, there is an increased likelihood of competition for prey with subordinate animals likely suffering more than dominant bears that can confiscate or monopolize prey. Because polar bears are not territorial, loss of habitat may not result in an immediate loss hunting opportunity through loss of individual home ranges as it would for terrestrial ursids. Regardless, it seems logical overall to predict that a major loss of sea ice habitat will result in a decline in polar bear abundance over time.
Polar bears preferentially feed on the blubber of their prey and adult bears in particular often leave much of the protein behind (Stirling and McEwan, 1975Go) and do not typically remain with prey (Stirling, 1974Go; Stirling and Archibald, 1977Go). Immature bears are not as efficient at catching seals (Stirling and Latour, 1978Go) and the remains of kills made by other bears may be important for this age class. It is possible that if polar bears experience decreased kill rates, greater use of kills may occur and result in relatively less food for younger bears to scavenge. Scavenging dynamics and competition for prey suggest age-related differences in response to climate warming.
Integrative and Comparative Biology 2004 44(2):163-176; doi:10.1093/icb/44.2.163
© 2004 by The Society for Integrative and Comparative Biology
Polar Bears in a Warming Climate
Andrew E. Derocher2,1, Nicholas J. Lunn2 and Ian Stirling2
http://icb.oxfordjournals.org/cgi/content/full/44/2/163
“Due to governmental regulations on hunting, the population has increased from an estimated 10,000 polar bears in 1968 (Stirling, 1988). ”
Note that this Ian Stirling is the same mentioned in your last post Pinxi, and the same who wrote this year warning of declines in polar bear numbers. Either he can’t make up his mind, he has changed ‘teams’ or he has noticed changes in bear numbers over his lengthy career studying them.
Thanks for the link to the Derocher et al article Pinxi. I am with you. There is mounting evidence that these animals are going to be in serious trouble if the environment they live in continues to be disrupted by climatic factors. This evidence is coming from well-respected, long-time researchers.
If the researchers were wrong, and the bears are fine, then everyone should be happy. If it goes the other way (like Pinxi’s cod), then we should all hang our heads in shame and another lesson wont have been learnt.
Zoo keepers will tell you that the most dangerous of all animals to work with in captivity are polar bears. They are cunning and serious predators, always watching the keeper’s routine to see when a door opens, how a latch is moved and so on. They are always looking for an escape. I question whether they agree with being locked up in a concrete Arctic World.
Not sure if some of the Stirling quotes have been taken out of context. Decline in what exactly would be the question I’d explore with more time. I saw some mentions of declines in specific populations but not sure how accurate.
The Derocher et al article is informative reading.
Thanks for the extra info as usual Libby.
So are the polar bears used by the greenhouse industry and the AGW folks to forward their message?
The Norwegian Polar Institute can hardly be blamed for ” NGO”-policy , neither Ian Stirling.
And what about Busho???
Ann: US legal obligations under the Endangered Species Act (sued by GP etc to add PBs to list). They’re getting around the potential extension of that obligation to include a need to address climate change by declaring it extraneous to endangered species issue.
http://www.nytimes.com/2006/12/28/science/28polar.html?ex=1324962000&en=50b37e5bde8ccc37&ei=5090&partner=rssuserland&emc=rss
http://www.washingtonpost.com/wp-dyn/content/article/2006/12/26/AR2006122601034.html
I think it’s safe enough to (blog rule) assume good faith by the polar bear institutes & scientists appearing in the various extracts above.
Washington Post states:” …The bears have resorted to open-water swimming and even cannibalism in an effort to stay alive…”
It must however be pointed out that our cute bears( polar bears, grizzlys and brown bears) have always had a tendency to cannibalism…
The males have a habit of trying to kill the male cubs….and to eat or bury the cadaver…
Don’t know if the researchers now have detected an increased tendency to cannibalism???
Save the baaaaars !
I’ve detected increasing instances of wingnut deniers eating their weasel words and out of context quoting. Amstrup is the go to guy on this species. Or you could declare them not a real species like these morons have at GM’s Corner? Denial is a sad thing. Truely sorry in every way.
Increasing? Not quite.
“We analyzed capture-recapture data collected from 1984-2004 by the Canadian Wildlife Service, and handling data for polar bears captured in and around the community of Churchill by the Manitoba Department of Conservation. We used Cormack-Jolly-Seber to estimate survival, population size, and population growth rate. We concluded that the total size of the WH polar bear population declined by approximately 22%, from 1194 (95% CI = 1020, 1368) in 1987 to 935 (95% CI = 794, 1076) in 2004. The correlation between earlier sea ice breakup and decreased survival provides quantitative evidence for a link between climatic warming and polar bear population dynamics. It may also help explain why Churchill, like other communities along the western coast of Hudson Bay, has experienced an increase in the number of bears that come into town prior to freeze-up each fall. The progressively earlier breakup of sea ice shortens the time that polar bears can hunt seals during the critical spring foraging season, thereby reducing their ability to accumulate the fat reserves they rely upon while stranded on land. The WH population is forced ashore earlier, in poorer nutritional condition, and remains food-deprived for a longer time. As polar bears exhaust their fat reserves toward the end of the ice-free period, they are more likely to encroach upon human settlements in search of alternative food sources to sustain themselves until freeze-up. Thus, the increase in polar bear-human interactions in western Hudson Bay probably* reflects an increase in nutritionally-stressed polar bears searching for food, not an increase in population size. Models developed and tested on the WHB project are currently being used for a new population estimation for polar bears of the Southern Beaufort Sea.” (Amstrup USGS 2006)
* This is unlikely to mean nothing of the sort is happening and the bears are just coming to town looking for lawn chairs and Coca Cola. Scientists never leap very far ahead to leaps of faith-based absolutism found in conservative polemics.
Luke: ” Save the baaaaars !”
Yeah Luke, let’s save the beers!!!!