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How will global warming affect polar bears?

What the science says...

Polar bears are in danger of extinction as well as many other species.

Climate Myth...

Polar bear numbers are increasing

“A leading Canadian authority on polar bears, Mitch Taylor, said: ‘We’re seeing an increase in bears that’s really unprecedented, and in places where we’re seeing a decrease in the population it’s from hunting, not from climate change.'” (Scotsman.com)

At a glance

Ursus maritimus. The Latin name for the world's largest bear hints at its high dependence on the seas around the Arctic. Polar bears are an apex predator that depend on seals for their food. Because of that dependence they mostly live and hunt out on the sea-ice. Excellent swimmers, they are equipped with the means to swim in the frigid Arctic waters. Thick body fat and a heavy, water-repellent coat make such a lifestyle feasible.

Polar bears live in 19 distinct groups around the Arctic. We don't have great data on eight of the groups. Arctic fieldwork is fraught with logistical problems, especially out on the sea-ice. Regarding the other groups, as of 2017, five are regarded as stable. Two are increasing whereas four are declining. Therefore, it's a mixed picture.

The reason why the picture is mixed lies in the four distinct eco-regions making up the Arctic. Let's look at these. Firstly there is the Seasonal Ice Ecoregion off Canada. Here, the ice has always melted in the summer. The bears hunt voraciously before that happens and then go through a seasonal fast on land. Unfortunately, because the ice-melt is beginning earlier and ending later, the fast period is getting longer, causing malnutrition and cub mortality. This bear population is the one that is definitely declining.

Stretching from Alaska to Svalbard is the Divergent Ice Ecoregion. Here, the ocean currents constantly move the sea-ice offshore as it forms. In summer, new ice does not form and a wide gap of open water exists between sea-ice and the land. Offshore, the sea ice is over the depths of the Arctic ocean - an area of relatively low food productivity. The seals remain near land, in the more productive shallows. Again, the problem facing the bears is the increased length of the ice-free season, for the same reasons as above. Bears living in this region are particularly vulnerable.

In the Convergent Ice Ecoregion, from the North Barents Sea around to Eastern Greenland, ice collects along the shore. The bears living in this region therefore have constant access to ice over shallow productive seas. Finally, there is the Archipelago Ecoregion, around the islands of the Canadian Arctic. Here too, the polar bears have been able to remain on the ice all year round. Both Ecoregions are therefore a known or potential stronghold for them.

The primary threat to all of these regions is obviously sea-ice loss due to climate change. As the sea-ice retreats, the bears have to spend more time on land. This can bring them into contact with human populations and such encounters tend not to end well.

Polar bears belong on the sea-ice. The long term trend for sea-ice extent is downward. Even if some populations are stable or even increasing, it's an uneven picture due to the differing characteristics of the regions they inhabit. Rapid Arctic climate change - Arctic Amplification as it's known - is real. Concern for this magnificent creature is entirely justified.

Please use this form to provide feedback about this new "At a glance" section. Read a more technical version below or dig deeper via the tabs above!


Further details

Polar bears are found in the Arctic circle and surrounding land masses. There are 19 recognised subpopulations, and estimates place their numbers at about 20,000 to 25,000. Polar bears are classed as vulnerable by the World Conservation Union (IUCN) and listed as a threatened species under the US Endangered Species Act. Yet some claim that polar bear numbers have increased since the 1950s and are now stable. So what is the situation for this species?

First of all, a few points need to be made about polar bear numbers:

  • Nobody really knows how many bears there were in the 1950s and 1960s. Estimates then were based on anecdotal evidence provided by hunters or explorers and not by scientific surveys.
  • Polar bears are affected by several factors on top of climate change, including hunting, pollution and oil extraction. The introduction of snowmobiles, aeroplanes and ice breakers and the increased hunting that followed led to a decline in certain populations.
  • On the other hand, the International Agreement on the Conservation of Polar Bears was introduced in 1973. That restricted or even banned hunting in some circumstances, resulting in a recovery of polar bear numbers.
  • Not all subpopulations are affected to the same degree by climate change. While some subpopulations are well studied, others are data-poor. That means there is insufficient information to make specific statements about current and past numbers.

With this caveat in mind, what do the figures actually say? According to a 2019 report by the World Wildlife Fund, of the 19 recognised subpopulations of polar bears, four are in decline, two are increasing, five are stable and eight don’t have enough data to draw any conclusions (fig. 1).

Population status of polar bears around the Arctic as of 2021

Figure 1: Population status of polar bears around the Arctic as of 2021. Data: Arctic Portal. Map: Wikipedia. Key to eco-regions, clockwise from bottom: EG = East Greenland; DS = Davis Strat; BB = Baffin Bay; KB = Kane Bay; SHB = Southern Hudson Bay; WHB = Western Hudson Bay; FB = Foxe Basin; GB = Gulf of Boothia; QE = Queen Elizabeth; NW = Norwegian Bay; LS = Lancaster Sound; VM = Viscount Melville Sound; MC = M'Clintock Channel; NBS = Northern Beaufort Sea; SBS = Southern Beaufort Sea; CS = Chukchi Sea; LVS = Laptev Sea; KS = Kara Sea; BS = Barents Sea.

Both habitat degradation and over-harvesting are responsible for the decline in some populations. To understand why the IUCN and US Endangered Species Act consider polar bears to be at risk, it is important to look at how rising temperatures are likely to affect their habitat in the future. Polar bears are highly specialised mammals which rely heavily on sea ice for food and other aspects of their life cycle. Satellite data show that Arctic sea ice has been decreasing for the past 30 years. Projections show that this trend will only continue as temperatures carry on rising. The changes in sea ice affect polar bears in several ways:

  • The early retreat of summer sea ice means that bears have less time to hunt and therefore less time to build up fat reserves.
  • The fragmentation and reduction in sea ice has several impacts. It forces the bears to swim longer distances, using up some of their fat reserves. It also reduces the number of seals, which are the bears’ main source of food, and impedes travelling and den making. And it also forces the bears to spend more time on land, with increased interactions with humans potentially leading to higher mortality.

To get an idea of the potential impacts of future climate change on polar bears, we can look at subpopulations found at the bears’ southern range, where habitat changes have been most noticeable so far. A good example is the western Hudson Bay subpopulation, which is one of the best studied. Here, ice floe break-up is taking place earlier than 30 years ago, effectively reducing the feeding period by about three weeks. As a result, the average weight of female polar bears dropped by about 21% between 1980 and 2004, and the population declined by 22% between 1987 and 2004. In Alaska, there is evidence of increased cub mortality caused by a decline in sea ice.

In conclusion, the reason polar bears have been classed as threatened comes from the impacts of future climate change on the bears’ habitat. You can read about these habitats, or 'Ecoregions', in the 2021 status report (PDF) issued by the IUCN/SSC Polar Bear Specialist Group. Ecoregions are based on the different ways in which the sea-ice behaves around the Arctic. Current analysis of subpopulations where data is sufficient clearly shows some are in decline, although some areas are too data-deficient to draw a conclusion so far. Further habitat degradation will, however, do nothing but increase the mounting threats to polar bears.

Last updated on 14 January 2024 by John Mason. View Archives

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Comments 51 to 74 out of 74:

  1. Seems to me that the OP should be updated to reflect the scientific findings that have been published since Sep 2010.
  2. The denier meme identified in the OP is a quote of Mitch Taylor who was billed as a “leading Canadian authority on polar bears.” Thanks to Peter Gleick, we now know that Mitch Taylor receives a monthly stipend from the arch-conservative US think-tank, The Hearltand Institute. For more details about the Taylor-Heartland connection, check out: “What passes for a Brain Trust at Heartland?” by Richard Littlemore, DeSmog Blog, Feb 24, 2012
  3. John, I'm working on the intermediate rebuttal so I'll update this one once I've finished it. Not sure if this has been posted on here, but here's Steven Amstrup's view on the misreporting/misrepresentation of the recent report published by the government of Nunavut.
  4. Is the PBSG report cited in the OP peer reviewed?
  5. Is it relevant that the IUCN Polar Bear Specialist Group, the creator of the 2009 report cited herein, excluded Mitch Taylor from the 2009 Copenhagen meeting, not because he wasn't eminently qualified on the topic of polar bears, but because he doesn't believe in global warming? Is that relevant to the science?
    Response: [DB] Even "if" true, not relevant.
  6. Below is the Polar Bear Population, by colony, from the Polar Bear Study Group site http://pbsg.npolar.no/en/status/status-table.html. Third column from the right is the Status. 5 groups are Reduced, 4 are Not Reduced, and 10 are Data Deficient. But based on that and on assumptions about what will happen if there is major glacier melt, They identify 8 will be trending down, 3 will be stable, and one will increase. But the estimate of risk says 6 are at very high risk, 1 is High Risk, 1 is a Moderate Risk, and 2 are at low Risk. Note that in the Chukchi Sea, they claim to not know how many bears there are, but they report them as trending down. In the Norwegian Bay, the Status is Data Deficient but they are listed as being at high risk of future decline. I read their last full report and found that link between the data in this chart and the projections of extinction seem to be smoke and mirrors. In the 1950's the population was about 5000. Today the population is 20,000-25,000. How can we be focusing on Polar Bear longevity when 250,000 children die every year from lack of a clean water supply. Our concern about polar bear extinction, now that hunting is under control, seems to be totally misplaced because of a photo of a polar bear cub sitting on a tiny piece of sea ice. Dave
  7. Dave, did you read the 'comment' links next to each statement? There is a justification for each of their evaluations, and it's certainly based on a lot more than a photo of a polar bear cub. Do you really believe the world is "focusing on Polar Bear longevity when 250,000 children die every year from lack of a clean water supply"? Do you not think the world is trying to solve both problems?
  8. Skywatcher, You may want to go back and check into those comment, too. Below are two examples of those comments about populations listed at "Very High Risk" of decline. "David Strait - New estimates of natural survival and current harvest suggest the population may begin to decline. Scientific and local knowledge suggest the population has significantly increased in the past." "Norwegian Bay-82% of PVA simulations resulted in population decline after 10 years; demographic data are 11 years old.Projections of decline are high also because of low sample size." Davis Strait is one of the larger populations and is listed as highly at risk of decline. This seems to say that we have some anecdotal data that the population used to be increasing, but our new estimates "suggest" the population "may" begin to DECLINE. The Norwegian Bay comment seems to say that they don't have any new data but we have a model (calculated from some very small sample that we do have) that says that if we had data, it could show us that there might be a decline. The above statements don't make me think there is significant data that this species is in trouble. I think PBSG should keep working and should get funding to understand what is happening. But we shouldn't be using their present results to say that Polar Bears have a global warming problem. There doesn't seem to be any data that supports that, based on their reports of increase or decrease in population. And yes, I do know there are programs going on to improve global water quality. But what I am concerned about is that we have limited resources - both the US and the rest of the world. There are lots of problems, both real and imagined. We need to prioritize how and where we spend those dollars based on real impact. [snip] Dave
    Response: [Dikran Marsupial] off-topic, all caps etc. snipped. Please familiarise yourself with the comments policy.
  9. matzdj (or do you prefer going by Dave as per your signature?): Please provide either better data or better statistical analysis/projections to support your claim: I read their last full report and found that link between the data in this chart and the projections of extinction seem to be smoke and mirrors. You can say what you like but without data or superior analysis compared to the PBSG you cannot substantiate such a claim and hence your opinion is as valuable as mine.
  10. matzdj @ 58... "The above statements don't make me think there is significant data that this species is in trouble." If you are seriously interested in this topic you might want to take the time to engage someone who is actively involved in the research. I can pretty much guarantee you that everyone doing the research is going to tell you that the species is very much in danger. What is the polar bears' primary habitat? Sea ice. Specifically summer sea ice prior to the winter when they are feeding on ring seals in preparation for the coming winter. The sea ice is disappearing at an alarming rate. Within 20 years the Arctic sea will seasonally ice-free. Habitat gone. Does that mean every last polar bear will die? No. But it means that there will be a massive and rapid change in their numbers.
  11. "How can we be focusing on Polar Bear longevity when 250,000 children die every year from lack of a clean water supply." What is this piece of rhetoric supposed to imply? The campaigns to reduce CO2 emissions are just about saving polar bears? Come on! Have a look at Dai 2010 and tell me whether not controlling emissions is going make things better for children needing drinking water. Stick to the science.
  12. Dave, the report is still based on much more substantive material than your opinion, which places its conclusions much higher up in the scale of credibility. As scaddenp suggests, stick to the science, and not rhetoric, as yet you have provided not one shred of evidence to support your assertions other than disliking a report's conclusions. Do you actually have evidence that polar bears will be fine? Or do you, like many skeptics, just continue to snipe at the hard work of others whose conclusions disagree with your unsubstantiated opinion?
  13. matzdj wrote : In the 1950's the population was about 5000. Anyone who brings up that number has obviously got it from somewhere dodgy, to be polite ! Either that or it has been taken without any checking or any real sceptical questioning. Have a look here for an investigation into that very suspect number. Actually, there isn't really any basis in fact for it.
  14. JMurphy, I stand corrected. I had taken that population of 5000 in 1950 as accepted data. I didn't understand that it may only have been a WAG. I guess we don't have a number to compare today's number with. The recent analyses from the PBSG group but seems to be reasonably well founded, although limited, at being around 20-25,000 Bears. However, their projections don't seem to based on that data, but on the fear of what might happen if all the ice melts. I think that defines a WAG. On the pbsg.npolar.no you can see the population status maps with comments. Davis Strait has about 10% of the total population and their comment is: "Population size of 2150 estimated using mark-recapture in 2007. Subpopulation likely increased over the last 30 years. Empirical birth and death rates suggest population is now declining." So the best data that they are willing to describe shows a likely increase. But a sample of birth and death rates (apparently too small a sample to document or lead to an updated population report) "suggests" the population is now declining. That led to a rating of Very High Risk of Future Decline. Boy that sounds like a weak reason to make such a strong projection. If there is more science or more data, why don't they describe it. I'm sure this group is doing good scientific work. However, they should limit their reporting to the data they have and how it projects. Now how it might project if something else changed. skywatcher and Composer99, I would like to stick with the science. The science from the PBSG is in their evaluation of the populations. i don't argue with that. But, If they were making projections solely based on the data they report, it is unlikely that they would come to the projections they discuss. Those projections are based on what will happen IF all the ice melts. That's like saying that we are in trouble if the sun becomes a supernova, and then worrying about it. I've been getting beaten up on other threads on this site because I am believe I saw something visually in the data that a statistical analysis didn't show because it averages things out. Where is the statistical analysis of the Polar Bear population that can be used to project their decline? scaddenp, I apologize for the rhetoric. What i was trying to say was that we have a limited amount of resources to apply to solving problems. Shouldn't we be applying those resources to problems that we know exist and that we can solve and will have benefit, instead of problems that we project because the data "suggests" that the problem "may" occur if some other event occurs. Let's keep watching the Polar Bear data and if it does ever show a decline in Polar Bear population, then we can consider worrying about it. Rob Honeycutt, (-snip-) Dave
    Response:

    [DB] The topic of this thread is Polar bear numbers are increasing, not changes in sea-ice-extent minimums (cf this post on Kinnard et al 2011) nor about the opening of the Northwest Passage (another must-read is this post on Arctic sea ice extent).

    Off-topic snipped.

  15. Using matzdj's logic one should let all bank robbers get away because not all bank robbers will actually leave the premises with the money after the teller hands it to them... Needless to say, matzdj's argumentarium is bereft of substance and replete with strawman rhetoric. matzdj, this website is an incredible resource for those actually interested in learning about climate science. For those of other persuasions, it is a tempting target. The choice of which path you are here to trod is before you now.
  16. " Shouldn't we be applying those resources to problems that we know exist" Yes, we should. And despite your attempts to deny, without scientific foundation to support them, dealing with climate change is one of them and quite possibly the most important one. At very least it will many other problems worst. Please try looking at the evidence instead of trying to warp reality to fit a what appears to be a preconceived notion about the reality of AGW.
  17. Those projections are based on what will happen if all the ice melts. That's like saying that we are in trouble if the sun becomes a supernova, and then worrying about it.
    To raise a general point here - there is very strong evidence that summer sea ice is on a strong and accelerating decline (see appropriate threads). There is little doubt that sea ice will continue to retreat, most likely to seasonally ice-free Arctic within a few decades. The consequences are generally agreed to be a bad thing for the polar bear populations that rely on hunting on the sea ice. If you don't think sea ice is both thinning and retreating, and accelerating in its decline, discuss on an appropriate thread with your evidence. Conversely, there is no evidence that the sun will become a supernova. In fact the current consensus in astronomy is that the Sun is too small to ever become a supernova. Even if all the matter in the Solar system was condensed into a white dwarf, the degenerate star would not have enough mass to become a Type 1a supernova, and of course the Sun lacks a stellar companion to give the extra mass required to cross the Chandrasekhar Limit (about 1.4 solar masses) to make a Type 1a supernova. Other supernova types require even more mass. One idea is supported by nearly all the evidence we have, the other has no evidential or theoretical support whatsoever. Why would you make such a comparison?
    Response: TC: "IFF" is an abbreviation for "if, and only if". "IF" on the other hand is only a violation of comments policy. Your future compliance with that policy is appreciated.
  18. matzdj, This issue is very simple. If warming continues unabated then eventually Arctic ice will melt for some or even large parts of the summer season. If this happens it is a destruction of the polar bear habitat for a very important part of their annual life cycle... it will shorten a hunting season that was already abbreviated by summer ice melt in 1970s conditions. For a human being, it would be like having a killing drought in August on every farm, every year for the next several hundred years (at a minimum). If you destroy an animal's habitat it will die or migrate. If it has nowhere to migrate, the only choice is to die... or to adapt and evolve, but I'm not sure that can happen when the habitat changes or disappears so quickly, and in any event, what would emerge would no longer be a polar bear. All of the evidence, no matter how sparse, points to a decline in polar bear populations, which is in keeping with all of the other science and observations (physics says the globe should warm, measurements show the globe is warming, measurements show the ice is retreating earlier and further each summer, etc.). But what really matters at this point is a measure in the change in habitat. One does not, after all, start to worry about drowning only when the water is already filling one's lungs. It helps to consider how deep the water is before diving in. Consider this report from the U.S. department of the Interior, which provides these graphs adapted from Durner et al 2009 (Predicting 21st-century polar bear habitat distribution from global climate models).
    Observed changes in the spatial distribution of optimal polar bear habitat from 1985 through 1995 to 1996 through 2006. The map shows the net change in the number of months per decadal period where optimal polar bear habitat was either lost (red) or gained (blue).
    Projected changes (based on 10 IPCC AR-4 general circulation models [GCMs] run with the SRES-A1B forcing scenario) in the spatial distribution of optimal polar bear habitat from 2001 through 2010 to 2041 through 2050.
    Consider these other recent studies: Projected poleward shift of king penguins' (Aptenodytes patagonicus) foraging range at the Crozet Islands, southern Indian Ocean Monitoring sea ice habitat fragmentation for polar bear conservation Rebuttal of "Polar Bear Population Forecasts: A Public-Policy Forecasting Audit" In the end this all falls back, as usual, on the typical denial cry of "but it hasn't happened yet." Like most things related to climate change, however, if you can unequivocally prove that it is happening, then it is already too late. The climate will have gone too far, and there's no chance to stop it. This is the true danger of climate change. Climate change is slow. Historically, it takes thousands to tens of thousands of years. We're doing it in a geologic blink of an eye, but on human time scales it is still "glacially slow" (pun intended). But the CO2 we add to the atmosphere now commits us to a future that we cannot reverse. The CO2 we have added to the atmosphere has already committed us to a future that we cannot reverse. It bears repeating (that pun was unintentional): Like most things related to climate change, however, if you can unequivocally prove that it is happening, then it is already too late. This is true of polar bears. It will be true of many habitats and species that may be impacted by climate change, such as the Amazon, coral reefs, and many, many more. As thinking beings, we have two abilities that exceed those of other animals (like polar bears). One is to think and to project and to plan, to take what we know about how the world works, put 2 + 2 together, and realize what is likely to happen. The second is to look at what data is available, even for things that have not yet happened, and to make reasonable projections. This applies to every aspect of climate change. Loud cries of "but it hasn't happened yet" are made to prey upon those who are too stressed and tired about other, immediate problems in their lives to bother to think ahead. Thank goodness some people don't take such a conservative, short-sighted and ultimately failed approach towards how we manage our civilization and our lives.
  19. Polar Bear populations are declining.

    In 2005, the IUCN Polar Bear Specialist Group (PBSG) classified the Polar Bear as a vulnerable species. In 2009, they reported that of the 19 subpopulations of Polar Bears:

    8 are declining
    3 are stable
    1 is increasing
    7 are without sufficient data

    This compares with, in 2005:

    5 declining
    5 five stable
    2 increasing
    7 data deficient

    [Source]

    · A decline in survival of female polar bears of all age classes, from 1194 to 806, between 1987 and 2011 in western Hudson Bay was due to earlier sea ice break-up in the spring and later freeze-up in the autumn.

    · In 2010, polar bear numbers in the southern Beaufort Sea appeared to stabilize at 900 bears following a period of low survival during 2004-2006 that led to a 25-50% decline in abundance. However, survival of sub-adult bears declined during the entire period.

    · Polar bear condition and reproductive rates have also declined in the southern Beaufort Sea, unlike in the adjacent Chukchi Sea, immediately to the west, where they have remained stable for 20 years. There are also now twice as many ice-free days in the southern Beaufort Sea as there are in the Chukchi Sea.

    · Genetic studies indicate that polar bears have been through long and dramatic periods of population decline during the last one million years, and that during periods with little sea ice there have been multiple episodes of interbreeding between polar bears and brown bears.

    [Source]

    "The primary habitat for polar bears and their prey, sea ice, is declining rapidly in extent in all seasons, and particularly in summer, with concurrent and even more dramatic reductions in total volume (Laxon et al. 2013). Since the satellite record began in 1979, minimum sea ice extent has declined 13.3% per decade (see the essay on Sea Ice). Given the close association between polar bears, their primary prey and sea ice, climate warming remains the most significant threat to the long-term survival of this species (Stirling and Derocher 1993, Amstrup et al. 2008, 2010)."

    [Source]

    The evidence is clear: Polar Bear populations are declining.

  20. I don't have the expertise to comment on it, but a non-peer reviewed paper claims the population is increaseing: https://peerj.com/preprints/2737/

    Of course we know that there is less sea ice, but maybe the biologists don't understand something.

    Response:

    [JH] Sloganeering snipped.

    Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

  21. The author of your citation is Susan Crockford.  She is an adjunct professor at the University of VIctoria.  Her expertise is in the breeding and history of dogs.  She is paid a monthly retainer from the Heartland Institute.

    No sign of expertise in polar bears, although she lives closer to their habitat than I do.  

    The article was submitted on March 2 for comments but no-one has seen fit to comment.  The impact factor of the journal is 2.2 which is very low.  If you have $400 you can get a pre-print on PeerJ.

    She purports to examine the status of polar bears when sea ice minimums are 3-5 mkm2.  Current projections are less than 1 mkm2 in  a few decades. Populations of long lived animals like polar bears change slowly in response to environmental changes.

  22. Michael Sweet says about Dr Crockford "No sign of expertise in polar bears"

    From Dr Crockfors's letter to the AIBS.

    https://wattsupwiththat.com/2017/12/05/retraction-request-for-harvey-et-al-attack-paper-on-dr-susan-crockford/

    "I am a professional zoologist with a Ph.D. and over forty years of experience and dozens of peer-reviewed papers on various topics, and also fails to mention that I have recently published a detailed academic critique on the issue of polar bear conservation status."

    "...my Ph.D. dissertation on speciation included polar bears"

    "In addition to my dissertation that features polar bears, I have an article on evolution in a peer-reviewed journal in which polar bears are prominently featured (Crockford 2003), and two official comments, with references, on polar bear hybridization (which is how official responses to published papers are handled in these two journals). I also have a paper in a peer-reviewed book chapter on ringed seals, the primary prey of polar bears (Crockford and Frederick 2011), and a peer-reviewed journal article on the paleohistory of Bering Sea ice, the habitat of Chukchi Sea polar bears (Crockford and Frederick 2007)."

    According to http://wwf.panda.org/what_we_do/where_we_work/arctic/wildlife/polar_bear/population/

    polar bear numbers are 22-31,000.

    From the literature I've read no-one seriously disputes they are currently in decline but computer models say they are threatened by future climate change.

    Michael Sweet said

    "She is paid a monthly retainer from the Heartland Institute."

    But she says...

    I am not “linked with” nor do I “receive support” from The Heartland Institute or any other corporate-funded think tank.

    either Michael Sweet or Dr Crockford is lying.

     

    Response:

    [DB]  Please note that posting comments here at SkS is a privilege, not a right.  This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

    Please take the time to review the policy and ensure future comments are in full compliance with it.  Thanks for your understanding and compliance in this matter.

    Personal attack snipped.  Also, note that the usage of sock puppets is frowned upon in this venue.

  23. Bruce @72 ..... with all due respect, Dr Crockford's expertise in evolution/speciation & hybridization of polar bears has near zero relevance to the modern situation where there is an extinction threat to the species.

    Polar bears are evolved for a specialized diet, and they do not have the fall-back position of an omnivorous diet (such as possessed by their ursine relatives).   The polar bears' hunting habitat is heading rapidly toward 100% loss over the next one-to-two centuries, thanks to Arctic warming (per AGW).

    Polar bear numbers (and importantly their condition) can be very difficult to determine accurately.  It is a bold, very bold, scientist who undertakes to publicly express a complacent attitude about the survival of a specialized mega-fauna carnivore which is undergoing almost complete loss of habitat.  Especially bold, for a scientist who is not a specialist "at the coal face".

    It appears Dr Crockford holds an outlier opinion, and is also making a mountain out of a molehill when it comes to relevant expertise.

    As to whether she is receiving financial benefits (from propaganda organizations such as Heartland, GWPF or other slush funds) in the form of a retainer or fee-for-service or stipend [see for instance the case of Emeritus Professor Lindzen or maybe Dr Judith Curry] or receiving non-cash benefits for speaking engagements etcetera ..... a cynic like you Bruce would of course wish see an absolutely categorical denial from her, that "none of the above" benefits apply to the present financial year nor any years of the past decade.   Alas, it is all too easy for propaganda organizations to arrange for covert benefits of various types.

    All too often in this world, Bruce, situations are more "gray" than you would wish.

  24. Bruce,

    According to this Desmog blog, Susan Crockford refused to respond to emails that asked aboout the money she gets from the Heartland Institute.  Desmog provides links to internal Heartland documents that say they pay Crockford.  Most of her claims are that she is a biological expert without mention of polar bears ie: " a paper in a peer-reviewed book chapter on ringed seals, the primary prey of polar bears (Crockford and Frederick 2011), and a peer-reviewed journal article on the paleohistory of Bering Sea ice,".

    Susan Crockford has never studied polar bears, her "detailed academic critique" (mentioned first by you so it must be important to you) is a blog post written for the Heartlad Institute.

    She is an adjunct professor which means she is part time in a position at the bottom rung of education. Hardly the position of an expert.  I am an adjunct professor at a college so I know what that is.

    Under no standard is she an expert in all biology as she claims.

    I await your apology since I have provided documentation that Susan Crockford receives money from the Heartland Institute.  Her denials are apparently false.

  25. Recommended supplemental reading:

    The global polar bear population is threatened by loss of sea ice, contrary to PragerU’s video claim by Vikki Forrester, Climate Feedback, May 18, 2020

    KEY TAKE AWAY: There is no scientific evidence that the global polar bear population is growing in size. Climate change induced losses in sea ice habitat is the most important threat to polar bear survival. Two polar bear subpopulations have already been negatively impacted by sea ice loss.

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