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No Reliable Data on Historical Polar Bear Numbers – A Note from Nichole Hoskin

Polar bears (Ursus maritimus) have become a symbol of global warming, and their predicted decline a sign of worst to come, but until very recently population estimates were really just educated guesses. Current polar bear numbers are estimated to total between 20,000 and 25,000.

On May 14 2008, when announcing the decision to list polar bears as threatened under the U.S. Endangered Species Act, Secretary for the U.S. Department of Interior, Dirk Kempthorne stated,

“Although the population of bears has grown from a low of about 12,000 in the late 1960’s to approximately 25,000 today, our scientists advise me that computer modeling projects a significant population decline by the year 2050.”

But there are no published papers or reports to support the claim that there were about 12,000 polar bears forty years ago.

At the 1968 meeting of International Union for the Conservation of Nature (IUCN) Polar Bear Specialist Group in Alaska, the Canadian Wildlife Service representatives suggested that numbers were as low as 5,000 in the 1950s and 1960s.

Current Chairman of the IUCN Polar Bear Specialist Group, Andrew Derocher, has stressed,

“The early estimates of polar bear abundance are a guess. There is no data at all for the 1950-60s. Nothing but guesses. We are sure the populations were being negatively affected by excess harvest (e.g., aircraft hunting, ship hunting, self-killing guns, traps, and no harvest limits). The harvest levels were huge and growing. The resulting low numbers of bears were due only to excess harvest but, again, it was simply a guess as to the number of bears.”

But how can Dr Derocher be sure that polar bear populations were being negatively affected by harvesting if there is no hard data on population numbers for the same period?

In 1972, at the 3rd Working Meeting of the IUCN Polar Bear Specialist group the Norwegian representative, Thor Larson, suggested there were as many as 20,000 in the late 1960s. Larson said,

“Merely by summarising the various national counts, which still must be considered inaccurate, one reaches the conclusion that the worlds total polar bear population is probably closer to 20,000 animals, than to the lower figures often suggested.”

Just maybe there have always been about 20,000 polar bears in the Arctic?

Nichole Hoskin is a research assistant at the Institute of Public Affairs and is adding to the Environmental Wiki associated with this blog.

———————
Other blog posts by Nichole Hoskin on polar bears include:
Polar Bears Can Survive where there is no Summer Sea Ice: A Note from Nichole Hoskin, August 20, 2008. http://www.jennifermarohasy.com/blog/archives/003342.html

This blog is a gathering place for people with a common interest in politics and the environment. We strive for tolerance and respect. We don’t always agree with what we publish, but we believe in giving people an opportunity to be heard.

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213 Responses to “No Reliable Data on Historical Polar Bear Numbers – A Note from Nichole Hoskin”

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  1. Comment from: Ivan (817 days & Counting)


    “It is more a consequence of empirically measured things. So we know that CO2 acts like a greenhouse gas, we know the concentration of CO2 is rising, we know human activities have increased the CO2 in the atmosphere… All these things are empirically measured.
    And are all verifiable.”

    …including the fact that the concentration of CO2 continues to rise, all the while temperatures have plateaued or have begun to trend downwards. That sounds like a compelling case for pissing billions more dollars down the drain.

    “The hot dry rock geothermal energy in Australia looks promising.”
    Oh yeah! Let’s bet our future on something that ‘looks promising’. Brilliant.

  2. Comment from: Nichole Hoskin


    NT,

    I didn’t say that courts have superior finding than scientists. All I pointed out was the fact that Australian courts will not blindly accept whatever opinion scientists express unless there is evidence that the expert opinion is based on evidence and not speculation.

  3. Comment from: NT


    Nichole, and your reason for saying that is…. Or is it just some interesting factoid?
    The implication that will be made is that science does just accept speculation.
    This is not true.

    The best bit about science is that you don’t go to jail or get fined for dissenting. If you disagree with a judge’s ruling, isn’t that contempt? Resulting in fines or jail?
    No such thing applies in science so people can freely dissent. Now THAT is a system for getting to the truth of a matter.

  4. Comment from: Travis


    There seems to be a side issue of law here, but I would like to know:

    So are all these experts (and no one has been missed) agreeing that ‘Just maybe there have always been about 20,000 polar bears in the Arctic?’

    If there is nothing to hide, it’s a straight forward affirmative.

  5. Comment from: Ann


    From a Norwegian fisheries paper:

    http://fiskeribladetfiskaren.no/default.asp?side=101&lesmer=8770

    Warmer water will not only have an impact on the sea ice and marine mammals , but it will change dramatically the conditions for organisms on the sea bottom , that are in the bottom of the food chain.

    Research has been carried out by the Polar Institute that show that waters in northwest of Svalbard have had a temperature increase of 5 degrees C. ( 2 degrees C is in natural variations).

    Bottom dwelling organisms are an indicator that something is happening with the ocean’s eco systems around the entire world, states a Professor at the Polar Institute.

    Another news from yesterday :

    Arctic sea ice now second-lowest on record

    “Sea ice extent has fallen below the 2005 minimum, previously the second-lowest extent recorded since the dawn of the satellite era. ”

    http://nsidc.org/arcticseaicenews/index.html

  6. Comment from: Libby


    Hello Jennifer and Nichole,

    I took it upon myself to contact Dr Andrew Derocher. I will not disclose the content of his correspondence with me. I have far too much respect for him to do that.

    Dr Derocher wrote a lengthy reply to my query about polar bear populations, and I have to say I am extremely disappointed by what is written in the opening piece to this thread, especially considering you contacted Dr Derocher personally. It is devious and highly misleading, and I have to agree with NT and Travis in that there is obviously an agenda here and it does not include reading the facts presented before you or listening to the experts. I am surprised at the level of some of the discussion here and the silliness, but I will say that Dr Derocher was too, especilly concerning Ian’s berries!

    I’ll pass on that there are a number of publications due out soon, such as on polar bear denning area loss, and there is a new paper available now on polar bears and climate change.

    I have always been reserved in my assessment of polar bears and the AGW debate. I believe the literature coming out on ringed seal recruitment rates, polar bear populations and so forth, but perhaps it is because I work in the marne mammal field. Dr Derocher painted a very gloomy picture indeed for the wildlife of the Arctic, based on his findings and those of his colleagues who have worked in this environment for many years.

    To those who will predictably boo me for not disclosing here what Dr Derocher said, too bad. In the polar bear debate, you are nobodies.

  7. Comment from: Nichole Hoskin


    Travis,

    I only briefly scan your comments to see if you are discussing something interesting/relevant to the blog piece. Since most of the time you are going off on tangents or attacking someone, I am bored with reading your long and often point-less comments.

    On Derocher and my emails to him, I included the links to these two blog pieces in an email to him. It is now up to him to check them out and decide if he wants to contribute to the comments or not.

    I would really like to hear from Derocher on what I have written. However, I am not going to start emailing him continuously because you tell me to.

    As for demanding details of my correspondence, I am not going to publish any correspondence I receive, without first gaining the consent of the other person. Since I don’t think this is important enough to bother Derocher with, I am not going to email him for his consent.

    Who do you think you are? I don’t have to prove myself to you.

    Why are you pushing so hard with the demands for me to get in contact with Derocher/reveal what was said? Fishing for something to jump up and down about?

  8. Comment from: Ann


    Thanks Libby! And a thanks as well to Luke , Travis and David ( isn’t it amazing that we all agree) !!!:)

  9. Comment from: Travis


    Nichole,

    Your response doesn’t surprise me in the slightest. I have no idea how you can conclude I am going off on tangents when I have provided you with information when asked on this thread and the previous, both ‘historial’ and new. I have kept to topic, regardless of the talk here on law and philosophy, Ivan’s constant trolling and some of the other comments. It seems that Mott can attack and still get responses and praise from you, so there are some obvious conclusions to be drawn there. Your opinion as to whether what I post is ‘relevant/interesting’ and that it is boring is simply that, and quite revealing. I took the time to reveal the contents of two papers you yourself cited, but perhaps you were not happy with what else the papers said regarding the point you were trying to make?

    >I would really like to hear from Derocher on what I have written. However, I am not going to start emailing him continuously because you tell me to.

    I’m sorry Nichole but I was under the impression from what was written here by Jennifer that you had already been in communication with Derocher and exchanges had been made. I was not continuously telling you to email him, I was continuously asking you to present your information. Please do not misrepresent me.

    >Who do you think you are? I don’t have to prove myself to you.

    Please, give it a break. You are adult enough to post threads here making certain claims and being selective with your information. If you didn’t want to be criticised for poor evidence, then perhaps you were expecting your readers to all be in total agreement with you, be quite silly or not give a toss? I’m not asking for you to prove yourself to me, simply your evidence and the point you are making. Please don’t manipulate it around to suggest otherwise or make yourself look like a victim.

    >Why are you pushing so hard with the demands for me to get in contact with Derocher/reveal what was said? Fishing for something to jump up and down about?

    Here is what Jennifer wrote:
    ‘But I asked Nichole to find some hard data, some reliable numbers, to at least support the idea that numbers have increased since the 1970s. Interestingly, she has spent days searching and reading and emailing experts, to conclude that there may have been as few as 5,000 bears 40 years ago, then again there may have been as many as 20,000.’

    Along with:
    ‘As regards experts, Nichole has been in correspondence with Derocher, Taylor and others. I don’t think there is anything or anyone she has missed.’

    Even David wrote:
    >As you note that Nichole has been in correspondence with Dr Derocher, then perhaps this question can be answered:

    “how can Dr Derocher be sure that polar bear populations were being negatively affected by harvesting”

    Is David a bad boy for asking??

    It now appears that you did not get a reply from Derocher, but it did not come across as that obvious in what was written.

    The reason I was asking about your emails to Derocher was because I wanted to know how you came up with the question ‘But how can Dr Derocher be sure that polar bear populations were being negatively affected by harvesting if there is no hard data on population numbers for the same period?’ But that is now pretty obvious! Telling me I am looking for something to jump up and down about is childish. I am looking for answers and facts Nichole, and so far a number of us (not just me) have been unsatisfied with what you have been putting forward.

    So please, dispense with the victim role and debate the science. Surely that is why we are all here?

    Thankyou Libby for your comment regarding Derocher. I would not expect you or Nichole to reveal the contents of Derocher’s email unless he had consented. I think you have said enough though for some conclusions to be drawn, and I think some of us knew them already.

    Gee, this post is likely just too long, boring and irrelevant for kindie concentrations and cognition.

  10. Comment from: Paul Biggs


    109 comments, and still no one has come up with solid historical or current polar bear numbers. I guess that’s what we call ‘uncertainty.’

    I do however have some Arctic news: “400,000 square miles more Arctic ice today than a year ago.”

  11. Comment from: Ann


    ” I do however have some Arctic news: ” 400 000 square miles more Arctic ice today than a year ago ” – Paul

    From my above link : ” The bottom line, however, is that the strong negative trend in summertime ice extent characterizing the past decade continues”

  12. Comment from: Paul Biggs


    400 000 square miles more Arctic ice today than a year ago, which is positive compared to last year.

    ” The bottom line, however, is that the strong negative trend in summertime ice extent characterizing the past decade continues”

    Which means or proves what exactly?

  13. Comment from: Ann


    From Reuters:

    ” As more Arctic ice melts, bears are forced to swim longer distances to find adequate platforms for hunting. Rescuing bears in distress in open water is problematic, Williams said: tranquilizing the bears sends them into the water to drown.

    The US government in May listed polar bears as a threatened species because their icy habitat was disappearing, but offered no plans to address climate change or drilling in the Arctic for fossil fuels that spur the climate-warming greenhouse effect.

    Summer ice melt in the Arctic is seen as a strong indicator of climate change, and feeds on itself in what scientists call a positive feedback loop where warming exposes dark sea water, which absorbs more solar radiation than the white ice.

    Arctic sea ice is sometimes dubbed Earth’s air conditioner for its ability to moderate world climate. In the last decade, this ice has declined by roughly 10 percent. ”

  14. Comment from: gavin


    Anne and Paul, please stop it now. You are making me chuckle

  15. Comment from: Ann


    You’r completely right Gavin, thanks!

    For readers info I have also today e-mailed Norwegian Polar Institute’s Polar bear expert, Dr Aars ( one of the name you see in the scientific paper together with Sterling, Derocher, Wiig , Taylor et al) posing some questions that readers here on the blog have asked.

    If I get a reply I might post them on my blog.

    I feel as well that my time has come to an end here ( again;)! but I will thank the readers.

  16. Comment from: gavin


    Locals could be more amused when they find the article headed “Global warming puts heat on Arctic ice cap” on page 13 in today’s Canberra Times with its accompanying picture (Reuters) of a floundering polar bear in cool grey waters.

    That’s a well illustrated item hey

    See the original Jean-Louis Santini article “Arctic ice cap ‘melting more than ever”

    http://www.theaustralian.news.com.au/story/0,25197,24254860-12377,00.html

    or here

    http://www.france24.com/20080828-north-pole-ice-cap-melting-faster-ever

    and in many other places on the www today.

    Howzat for pouring oil on a brewing storm?

  17. Comment from: Ian Mott


    Note how Libby had every opportunity to correct any misconceptions about the actual nutritional value of berries but chose, instead, to give us a bit of hearsay. If Derocher had actually mentioned some relevant facts on this issue then Libby would always have been free to repeat those facts. And from this we can conclude that either, Derocher did not provide any facts, or that the facts did not reconcile with Derocher’s or Libby’s opinion.

    So once more, does anyone have detailed and specific research that would indicate that it takes a whole lot more than about 30 to 40kg of berries per day to deliver the same energy budget as eating 1.5 baby seals each week?

    I will be quite happy to be corrected by credible evidence.

  18. Comment from: Travis


    You just don’t get it do you Mott? BTW, you are off-topic, but I’m sure Nichole wont mind.

  19. Comment from: NT


    Ian, I sent you two papers on how important berries were to PB diet… You seem to be unable to read?

  20. Comment from: Paul Biggs


    http://icecap.us/images/uploads/ArcticCanada.JPG

    Looks as though Polar Bears survived warming 7000 and 1000 years ago.

  21. Comment from: Travis


    Paul, the ability of the bears to survive during that period says nothing about how the bears will survive during a period of warming now. The animals are now specialised to live off the ice. The western Hudson Bay population has ice-free periods where they occasionally eat berries but live off their fat reserves. If warming happens at a rate where the bears AND their prey cannot adapt, they won’t.

    I don’t know why people go back to the argument of what happened to PBs during this warming period. I don’t think any PB scientists were there at the time to note what really went on and it is pretty irrelevant to what is happening today. The PBs we see today are adpated to the habitat they live in. A basic understanding of ecology would allow you to put this argument in context and focus on the real issues.

  22. Comment from: Nichole Hoskin


    Travis,

    Yes I have made positive comments to Ian Mott. Did it occur to you that I was doing it because I know that you and others will attack him and I appreciate his contributions because he provides a different view to the majority of commentors.

    As Voltaire once said, I might not agree with you opinion but I will die for your right to say it–its called encourage diverse participation and freedom of speech

  23. Comment from: Nichole Hoskin


    Travis,

    Your ‘revealing of the contents’ didn’t tell me anything I didn’t already know, although your interpretation was novel in some parts. It bored me.

    Plus, if you really wanted to make the relevant contrary argument to my piece on western Hudson Bay, you would have read the justification section of the IUCN Red List for Polar Bears. One of the links in the present piece will take you to it. There Derocher et al argue that the reason that polar bears will not be able to adapt is because climate change will happen too rapidly. Since my first piece on polar bears raised the point that polar bears might be able to adapt….shouldn’t the counter argument focus on why scientist think they won’t be able to adapt?

    For me, Derocher et al.’s argument is inherently speculation since it is a prediction about the future. Unless Derocher et al are psychics or time-travellers, I don’t know how they have observational data that proves there claims.

  24. Comment from: Nichole Hoskin


    Travis,

    I don’t expect people to agree with me! In fact, I enjoy exchanging ideas, passionate arguments and the opportunity to consider a variety of views.

    However, I find it frustrating when you make assumptions that you have no evidence to prove, excessively quote (probably a breach of copyright) from articles I have read and resort to personal attacks when you are unable to come up with a valid contrary argument. Its childish. It puts others off from contributing because they know that if you disagree, you will resort to school bully behaviour.

    I am not saying don’t disagree, I am saying do it in an manner that is respectful of others and supports diverse contributions

    On the fact that others joined in on your campaign for me to post the emails, its amazing that those who tend to agree with each other tend to support each other. Kinda like what I was trying to do with Ian Mott, although since I don’t have any evidence of David’s motivations, I am not going to speculate on them.

  25. Comment from: Nichole Hoskin


    Travis,

    I got two replies from Derocher because I asked two questions.

    Since your fascinated with who I email, I also got a reply from Dr Nick Lunn, at the Canadian Wildlife Service.

    However, I would like a detailed response from Derocher on his views on what I have written. But that is something that he can choose to do if he wishes, after he has read the links I sent him.

  26. Comment from: Nichole Hoskin


    Travis,

    You better go back and read Derocher’s paper on Terrestrial Feeding observed in Polar Bears. He clearly states that we do not know how significant vegetation is for polar bears since we don’t know how whether polar bears get comparable energy from eating berries etc as they do from eating ringed seals.

    Until that question is resolved, it is impossible to say that polar bears live off fat reserves exclusively!

  27. Comment from: Nichole Hoskin


    Travis,

    You better go back and read Derocher’s paper on Terrestrial Feeding. He clearly states that we do not know how significant vegetation is for polar bears since we don’t know whether polar bears get comparable energy from eating berries, other animals etc as they do from eating ringed seals.

    Until that question is resolved, it is impossible to say that polar bears live off fat reserves exclusively!

  28. Comment from: Ian Mott


    Exactly, Nichole. Travis et al would have us believe that PBs MUST live off their fat reserves when feeding on berries but the initial evidence on berry nutrition indicates that there need be no reduction in fat reserves whenever berries are available.

    Indeed, there would have to be a major departure between Blackberry/Raspberry nutritional levels and Cloud Berry and other local berry species for the conventional assumption to apply.

    Note that NT has claimed that he provided links that refuted my conclusion but, pointedly, has not done a copy and paste of any alternate data.

    The entire melting ice/PB threat “scarenario” is based on this false assumption that PBs will still lose fat reserves when feeding on berries.

    Yet, the consumption of only 30 to 40kg of berries each day is not a big ask, especially for an animal with thick fur to protect against the thorns. So a mere 15kg to cover base metabolism, and thereby make no drawdown on fat reserves is in the realm of substantial probability.

    The real irony in all this is that on one hand we have the vegan/green left demanding that one species of omnivores (humans) should reduce their consumption of meat products in the interests of planetary sustainability. Yet, the very notion that another of the major omnivore species, the Polar/Brown Bears, might voluntarily do so in response to cyclical climatic variation is regarded as gross calumny. Go figure.

    One interesting aspect of Derocher’s papers is the breakdown of fat utilisation during hunting. We are told that of a 22kg weekly gross fat intake, some 10kg is added to fat reserves while 6kg (0.85kg/day) is base metabolism and another 6kg is expended on hunting. We are also told that this act of hunting involves travelling 15km each day (105km/week).

    This works out at about 57 grams of fat for each kilometre travelled which, multiplied by the standard 37.656kj/gram comes to only 2,146kj/km. Divide this by the 2180kj in a KG of berries and we find that a bear must only find 984 grams of berries in each kilometre of browsing to cover the energy used in finding those berries.

    And if we allocate the fat required for base metabolism to each of these 15km browsings then the total only doubles to 1.97kg/km of browsing. From this, we can only conclude that even the extremely sparsely distributed berry resources are capable of significantly augmenting Polar Bear fat reserves. A good thick berry patch can produce tonnes of berries per hectare while a 1km transect at a notional 2 metres wide only covers 0.2 of a hectare.

    And that, folks, means “Myth Busted”.

  29. Comment from: Travis


    >Did it occur to you that I was doing it because I know that you and others will attack him

    Um, I take it you are aware of the abuse Ian Mott has dished out to myself and others here, including threatening to kill my mother’s cat?? With a comment such as this Nichole, there really is not much use in trying to engage in sensible discussion with you. Ian Mott’s comments on berries were made up by himself. I gather this is the sort of different view you appreciate? His retort to Libby and conclusions regarding her communication with Derocher should hardly sit well with a lawyer.

    >its called encourage diverse participation and freedom of speech

    That’s fine, but be consistent with your citicism of posters here – Ivan being a notable example.

    >Your ‘revealing of the contents’ didn’t tell me anything I didn’t already know, although your interpretation was novel in some parts. It bored me.

    I didn’t do it for you Nichole. I did it for readers who do not have access to the papers you cited and who are too lazy to read links. I have no interest in whether it bored you or not, and as you don’t seem to understand their contents, I’m not surprised.

    >Since my first piece on polar bears raised the point that polar bears might be able to adapt….shouldn’t the counter argument focus on why scientist think they won’t be able to adapt?

    The first peice from papers published in 1993 and 1998 did not put forward convincing evidence to support your claim that PBs might be able to adapt. You are mispresentng what the authors wrote. It was always known that the western Hudson Bay pop comes ashore in ice-free areas and fasts. Look at the latitude for this location compared with the rest of the pops of PBs. The papers did not say they could sustain themselves on berries, showed that males there rarely eat berries (even though their energy demands are very high), suggested why females with cubs go inland, and said quiet plainly that there are not enough foods like berries available to sustain these animals. If they could eat berries and adapt, why don’t they do so with more frequency? Why haven’t more recent studies suggested this? Why are papers still saying they live off their fat reserves? Why are these same authors you cited stating that PBs can not grow to be as large as they are on a diet of vegetation? As Derocher, Stirling and others have spent many years studying these animals and understanding the conditions they live in, I think they are well-placed to say that they will have problenms adapting if c/c happens too fast. I have provided information that has shown ringed seals (PB prey) are not adapting well to the changing conditions. There is other evidence out there to support it, which I’m sure you are aware of. So the scientists out there are putting forward counter arguments based on their studies and what is known of the bears, their prey and their environment. Why are you arguing with these reserachers? Who are you to disagree? In fact you have contradicted yourself here by first saying that your cited papers suggest PBs can adapt and then saying that Derocher claims they can’t if c/c happens too fast. Derocher was involved in the papers you cited! So (a) you are continuing to cherry pick information from the papers you cited, (b) you are refusing to accept more recent findings on PBs (c) you are continuing to disagree with experts who actually know something about PBS.

    >For me, Derocher et al.’s argument is inherently speculation since it is a prediction about the future.

    This is not all about the future. The changes are happening now and the research is showing it. I’m not sure why you refuse to accept or acknowledge it.

    >when you are unable to come up with a valid contrary argument

    That is your opinion Nichole, and going by what you have just written, not surprising at all.

    >It puts others off from contributing because they know that if you disagree, you will resort to school bully behaviour.

    So you can condone the trolling of Ivan, the bullying of Mott and the suggestion of killing PBs here? You have evidence it puts people off contributing? I could just as easily say that your inability to produce a valid argument to support your claims and understand the evidence before you also puts people off.

    >On the fact that others joined in on your campaign for me to post the emails, its amazing that those who tend to agree with each other tend to support each other.

    So? People here have their own opinions. They have tried to express them. Most often you have not listened to the side you are not in agreement with. They want answers and proof. Is that not fair enough? The fact that a marine mammal researcher like Libby decided to go to the source for information (Derocher) is not a glowing endorsement of what you have argued so far. If folk here want to do their own research into the matter, then I think it shows initiative and says something about the arguments and evidence you are presenting. It does not necessarily show that those in agreement show support. That’s your opinion again, and the point is hardly important to the topic at hand is it?

    >although since I don’t have any evidence of David’s motivations, I am not going to speculate on them.

    Of course not! He is usually on your side! But you are going to speculate on Ann’s and Libby’s and mine! You are very transparent with your alliances.

    >Since your fascinated with who I email, I also got a reply from Dr Nick Lunn, at the Canadian Wildlife Service.

    I am glad you have received replies from Derocher and Lunn. Hopefully they can contribute to the discussion here. Again you are misrepresnting me Nichole. I am not ‘fascinated’ with who you email. That is an immature response and undermines the intellectual interest I have in this topic.

    >Until that question is resolved, it is impossible to say that polar bears live off fat reserves exclusively!

    Nichole the paper was published in 1993. We are talking about one population of PBs with a southerly distribution. The author has since said the bears cannot get so big on berries. I have gone over this above and previously. There have been studies done on grizzlies and berries. I suggest you look over them. Any berry significance should have been well and truly researched by now (especially in light of c/c) and will only be valid for the populations of PBs that have access to berries, which are very, very few and in varying quantities and monthly availablility. No one is disputing that some PBs were shown to eat some berries. The paper says they can supplement their diet with berries. However it also suggests that males tend to live off their fat reserves exclusively. If berries were so important for these larger and more energy-demanding animals, surely they would be out eating berries, when they are available and where they are available??

    It seems you are still misinterpreting the information in the papers you cited in order to grasp onto an argument you have already formed. I hope that Derocher rsponds to you, I really do. If he does not, should you draw conclusions from that?

    BTW, I notice you have put in 6 consecutive posts (hence my lengthy and no doubt boring reply here). I trust your fair judgement of others such as myself should we do the same is as consistent as your judgement on relevance, courtesy and facts. I have also metered my response to the level of civility you have granted to me.

  30. Comment from: Zach


    “Note that NT has claimed that he provided links that refuted my conclusion but, pointedly, has not done a copy and paste of any alternate data.”

    Perhaps he would be breaching copyright!

    “And that, folks, means “Myth Busted”.”

    I am so glad the reseachers don’t need to do any research any more but just rely on Ian’s wisdom and expertise. What a bloody joke! The science of the deniers is never in any doubt. No wonder Nicole supports you.

    Travis, why do you or Ann or NT bother? I for one appreciate your efforts, but these people are fruitcakes with a fantasy view of the world. I just wish they lived in a separate one altogether.

  31. Comment from: Ann Novek


    A short last input here. I got replies from Dr Aars , from the Norwegian Polar Institute ,and I will even question him more and might post the replies on my blog if I got his consent.

    However, methinks it’s OK to post one reply here .

    I asked Dr Aar’s if polar bear researchers could use DNA to calculate historical population estimates?

    He said such methods were very uncertain, I mentioned Palumbi’s work with grey whales, but he said they were uncertain and got criticism. He didn’t believe such methods could be used on polar bears in the future.

  32. Comment from: Ann Novek


    Dr. Jon Aars is as well a permanent member of the Norwegian delegations IUCN Polar Bear Specialist Group

  33. Comment from: Nichole Hoskin


    Travis,

    Go back and read the comments above where I thanked NT for drawing my attention to the retraction of an opinion on sea ice extent. Who is selective and inconsistent?

  34. Comment from: Nichole Hoskin


    Zach,

    Resorting to analogies with holocaust deniers is petty. Since denying the Holocaust is a crime in Europe and relates to denying historical fact….explain to me why it is the same as questioning predictions about the future.

  35. Comment from: Nichole Hoskin


    Travis,

    Once again you show us all that you have poor comprehension skills. When did I supporting killing polar bears? In fact, if you read what I commented to Ann, I said I don’t have an opinion on harvesting per see and that I am not necessarily in favour of harvesting of polar bears.

  36. Comment from: Ian Mott


    So, as expected, lots of rhetoric to obscure the fact that they have made no response to the calculation, based on Derocher’s own information, and freely available berry nutrition data, that a bear only needs to find 2kg of berries, or lichen equivalent, to cover base metablism and energy used in browsing for 1 kilometre.

    Lots of generalised opinion but a consistent refusal to shift from the general to the specifics of this issue. They continue to cite surveys showing a lack of berry consumption, but based on populations that still have good ice cover.

    Key fact, folks, berries dont grow on ice. But if the discussion is of a speculative nature as to the likely consequences of a reduction in ice cover then why would anyone continue to quote ice based surveys? Hello? Is anyone home?

    And why would anyone continue to cite surveys of entire populations when it is the sub-population of breeding females and adolescents that eat the berries? It is the retained fat reserves of females and adolescents that has been highlighted as critical to species survival.

    Interestingly, if Derocher’s average body fat budget of 22kg/week is derived from a survey that includes the much larger males then the minimum berry consumption threshholds indicated in my above posts would be smaller still for females and adolescents.

    No wonder the climate alarmists are so keen to ignore the whole issue.

  37. Comment from: Tom Melville


    Ian Mott: I must say that one of the real pleasures of reading this blog is finding one of these situations where you completely dismantle these green myths with the basic maths of the issue. The “bull$hitistanis” as you call them really don’t like any consideration of the basic maths because it always brings them undone.

    But you should have extended the 2kg/km figure to give a minimum berry volume per hectare of land. That is, 1km distance x 2 metres wide = 2000m2, so 2kg/0.2ha = 10kg/ha. That is a really sparse distribution of berries in a landscape and a good indicator of why the females and adolescents are likely to exploit this food source whenever it is available.

  38. Comment from: Nichole Hoskin


    Thanks Ann.

    That makes sense with what I know about DNA technology, in a criminal law context. DNA evidence, as used in Australian criminal trials, is a statistical probability, with a one in a 100,000,000 probability that there would be someone else, who is not related to the ‘offender’, having the same DNA profile as the offender.

  39. Comment from: Nichole Hoskin


    Zach,

    Just because you don’t agree doesn’t make everyone else wrong.

    Why do you come here and read the comments if you think we are all fruitcakes?

  40. Comment from: Nichole Hoskin


    Travis,

    I wish you would extend me the same civility I extend to you. When I questioned your interpretation of the articles, I refered to your interesting interpretation.

    When you questioned my interpretation of the articles, you accused me of misrepresentation.

    How is that the same civility?

    It’s ironic that you accuse me of misrepresentation and then proceed to misrepresent my views on harvesting of polar bears.

    Your lack of attention to detail became apparent when you were obsessed with the title of my 1st blog, yet you repeatedly mis-spelt my name, which was also in the title.

  41. Comment from: Travis


    >When did I supporting killing polar bears?

    This is what I wrote Nichole…’So you can condone the trolling of Ivan, the bullying of Mott and the suggestion of killing PBs here?’ I did not say YOU suggested killing PBs. I was referring to what a couple of other posters suggested with regards to killing PBs. These comments (along with Ivan’s irrelevance and trolling) drew no remarks from you and yet when I post information I am told it is boring, off-topic….So any ‘poor comprehension skills’ are entirely your own. I read your comment to Ann re harvesting and took it on board.

    >I wish you would extend me the same civility I extend to you.

    Nichole you have just written here that my information is boring, off-topic, that I have no comprehension skills. In what way are you being somehow more civil to me than I was to you in my last post??

    If I accuse you of misinterpretation, it is being civil. There were no attacks or ad homs, it was a basic comment that you had not represented accurately what I had written. How is this being uncivil?

    >It’s ironic that you accuse me of misrepresentation and then proceed to misrepresent my views on harvesting of polar bears.

    I have just cleared this up here. Hopefully you can understand it.

    >Your lack of attention to detail became apparent when you were obsessed with the title of my 1st blog, yet you repeatedly mis-spelt my name, which was also in the title.

    Now you really are sounding desperate and irrational. Read back – others have mispelt your name. I actually APOLOGISED to you when I found I was doing it. The fact you have singled me out here smacks of your own victimisation against me. It doesn’t matter to you that others did it or that I apologised. If you are miffed at me for making counter-claims against your arguments Nichole, then say so, but please drop this petty victim stance that is hypocritical at best, and your own form of victimisation against a poster at worst.

    My ‘obsession’ with your first title was because it was misleading. I’ve gone over this a number of times and presented information to support this view. You can’t seem to comprehend this though and continue along the same path, selecting out what you consider to be noteworthy pieces that support the view of your title. It is my attention to detail that has questioned why you have been so deliberately selective.

    I see that Mott continues to push his made up information on PBs and berry consumption. For a start this is off-topic. It is also not based on fact, but based on speculation, something which a number of posters here have made clear they do not like with when it comes to PBs. The double standards, inconsistencies and selectivity of some here is really quite amazing.

    Here is something that perhaps Nichole, Mott and now Tom Meville may like to read:-

    http://www.esajournals.org/perlserv/?request=get-abstract&issn=0012-9658&volume=078&issue=04&page=1105&ct=1

    Of course an abstract is just that, and to get a full understanding, it is anticipated that you will read the entire article.

  42. Comment from: Travis


    And here is another one:-

    http://www.journals.uchicago.edu/doi/abs/10.1086/374279

  43. Comment from: Travis


    >yet you repeatedly mis-spelt my name, which was also in the title.

    Let’s collate some data here: David and J. Hansford attributed the thread to Jennifer. Hillary Gibbons called you Nicole, Mott called you Nicole, Ann called you Nicole, NT called you Nicole (repeatedly, gosh!). I called you Nicole repeatedly and apologised for it. If it was such an issue for you, why didn’t you raise it earlier, like on the previous thread when I was mispelling it???

  44. Comment from: david@tokyo


    > David’s motivations

    I like sustainable whaling, and other examples of sustainable use.

    > He is usually on your side!

    I don’t recall ever being involved in other discussions with Nichole, so I don’t know how such a judgement might be made.

    > David and J. Hansford attributed the thread to Jennifer.

    No I didn’t. I only addressed a comment to Jennifer after I saw a comment from her mentioning that Nichole had been in contact with Mr. Derocher.

    Please leave me out of the squabbles.

  45. Comment from: Travis


    >No I didn’t.

    I did not say it was YOU, I said it was David. It’s quite possible that other Davids read and comment here.

  46. Comment from: Nichole Hoskin


    Travis,

    I didn’t comment because Ivan’s suggestion appeared to me to be black humour. Plus, they haven’t accused me of misrepresenting Derocher’s paper. If you the poke a tiger, you should expect to get bitten.

    On the name thing, it wasn’t an issue for me, thats why I didn’t raise it. It was an example of your lack of attention to detail.
    Ivan always spelt my name correctly and from memory Ian Mott did from pretty early on.

  47. Comment from: Nichole Hoskin


    Travis,

    “If I accuse you of misinterpretation, it is being civil.” If you think that you are being civil, then why do you consider my responses to be uncivil? Maybe you should consider your part in the interactions instead of focusing on what everyone is saying back to you after you make inflammatory comments

    Besides, this is a side-track.

    Show me how I ‘misrepresented’ papers I cited? Your previous argument appeared to be that because I misrepresented the papers I cited by not refering to papers on climate change, which would raise a whole range of different issues not relevant to the point I was making.

    Prove that I misrepresented the papers. Point to the statements I made that you think ‘misrepresents’ the papers cited by me in the piece.

  48. Comment from: Jennifer Marohasy


    Libby, I was interested to read in your comment in the above thread that you are “extremely disappointed by what is written in the opening piece to this thread”. But can you tell me what is factually wrong with it?
    Cheers,

  49. Comment from: Ian Mott


    Yes, every reader should take a good look at the links that Travis supplied just above. And lets all hope that you can glean a great deal more from it than poor Travis, who seems to read things only to the point when he thinks his prejudices may be served.

    He saw some initial information from Welsh et al that pointed to an upper limit to the physical ability of bears to eat berries and assumed that this supported his broader position that PBs without ice pack must lose body fat.

    So lets just run the calculator over the numbers for him, shall we? Welsh said;

    “Maximum intakes ranged from 30 g/min for 0.5-g berries to >200 g/min for 4.2-g fruits”.

    But if Travis had shown even minimal intellectual curiosity he would have multiplied the bottom of the range 30g/min intake by 60 minutes and at least 22 hours in the Arctic summer daytime and discovered that this amounted to 1.8kg/hour and 39.6kg each day.

    And when we multiply this total by the 2180kj in each nominal kg of berries we get 86,328kj, divided by the 37.656kj in each gram of fat then we have an equivalent of 2.292kg of fat intake per day or 16kg/week. And if, as Derocher has indicated, it takes 1.5 baby seals to produce 22kg of fat then this lowest range berry intake is the equivalent of 1.09 baby seals/week.

    But wait, there is also the upper range. If Travis had multiplied the upper range intake of 200g/min by the same 60 minutes and 22 hours he would have discovered that this amounted to a massive 12kg/hour and 264kg per day.

    And when we multiply this total by the 2180kj in each nominal kg of berries we get 575,520kj, divided by the 37.656kj in each gram of fat then we have an equivalent of 15.283kg of fat intake per day or 107kg/week. And using Derocher’s average, this is the equivalent of 7.3 baby seals each week.

    Please note, however, that:

    “The highest bite rates were obtained during the initial encounter with each patch as bears consumed all visually apparent fruits on the surface. Bite rates quickly dropped by 15–20% as foraging continued within the patch”.

    So we should reduce the above mentioned range of berry consumption and baby seal equivalents by 20%, but keep in mind that;

    “Maximum bite rates were not depressed until initial fruit density fell to <50 berries/m3″.

    Now lets see, berry size varied between 0.5g and 4.2g each. So this lower fruit density of 50/m3 would give a lower range of fruit volume of between 25g/m3 for small berries and 210g/m3 for large berries.

    More importantly, note that;

    “Maximum daily fresh fruit intake for the captive bears averaged 34 ± 6% (mean ± 1 sd) of body mass”.

    Yes folks, you did read that correctly, the average maximum intake was 34% of body mass. And the average body mass of a female PB is?

    Furthermore, the link to Felicetti tels us that;

    “Daily fat gain was up to three times higher in bears fed low-protein diets ad lib., compared with bears consuming the higher-protein diet and gaining mass at the same rate. Thus, bears eating fruit can either consume other foods to increase dietary protein content and reduce energy expenditure, intake, and potentially foraging time or overeat high-fruit diets and use diet-induced thermogenesis and fat synthesis to deal with their skewed energy-to-protein ratio. These are not discrete options but a continuum that creates numerous solutions for balancing energy expenditure, intake, foraging time, fat accumulation, and ultimately fitness, depending on food availability, foraging efficiency, bear size, and body condition”.

    So we have clear evidence that the range of berry intakes and resulting nutritional budgets exhibited by bears is significantly greater than the so-called “fasting rates” that have been claimed by the Polar Bear alarmists to be the inescapable doom of this species if polar ice sheets are reduced.

    The limits on bears capacity to substitute berries for seal meat are far above the average energy budgets experienced by PBs hunting on ice sheets.

    Indeed, there are sufficient grounds to investigate whether PB populations may even increase if a warmer climate were to increase the distribution, density and duration of vegetative food sources as the ice sheet dependent carnivorous part of their diet decreases.

  50. Comment from: Tom Melville


    According to Wikipedia, “an adult male weighs around 400–680 kg (880–1,500 lb),[2] while an adult female is about half that size”. See http://en.wikipedia.org/wiki/Polar_Bear

    So a 300kg female Polar Bear could consume 100KG of berries each day if they were available. That is one “kick-ass” calculator you have there Ian.

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