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Wednesday 13 March 2013

Polar Bears are doing well

Global Warming Policy Foundation

1) Polar bears are a conservation success story
Their numbers have rebounded remarkably since 1973 and we can say for sure that there are more polar bears now than there were 40 years ago. Although we cannot state the precise amount that populations have increased (which is true for many species – counts are usually undertaken only after a major decline is noticeable), polar bears join a long list of other marine mammals whose populations rebounded spectacularly after unregulated hunting stopped: sea otters, all eight species of fur seals, walrus, both species of elephant seal, and whales of all kinds (including grey, right, bowhead, humpback, sei, fin, blue and sperm whales). Once surveys have been completed for the four sub-populations of polar bears whose numbers are currently listed as zero, the total world population will almost certainly rise to well above the current official estimate of 20,000-25,000 (perhaps to 27,000-32,000?).

2) The only polar bear subpopulation that has had a statistically significant decline in recent years is the one in
Western Hudson Bay. A few others have been presumed to be decreasing, based on suspicions of over-harvest- of over-harvest of over-harvesting, assumed repercussions of reduced sea ice and/or statistically insignificant declines in body condition – not actual population declines.

3) Polar bears in the
US portion of the Chukchi Sea are in good condition and reproducing well, while sea ice in the Bering Sea has rebounded from record lows over the last ten years – good reasons not to be worried about polar bears in the Chukchi.

4) A survey by the
Nunavut government in 2011 showed that polar bear numbers in Western Hudson Bay have not declined since 2004 as predicted and all available evidence indicates that Hudson Bay sea ice is not on a steadily precipitous decline – good reasons not to be worried about Hudson Bay bears.

Full report

Dr Susan Crockford
Dr Susan Crockford is an evolutionary biologist and an expert on polar bear evolution. She has been working for 35 years in archaeozoology, paleozoology and forensic zoology and is an adjunct professor at the University of Victoria, British Columbia, Canada. She is the author of Rhythms of Life: Thyroid Hormone and the Origin of Species.



Matt Ridley: We Should Be Listening To Susan Crockford
The Global Warming Policy Foundation, 13 March 2013

Foreword To Susan Crockford’s Ten Good Reasons Not To Worry About Polar Bears

In 1978 three friends and I spent six weeks camped in a valley in Spitsbergen. The possibility that we would meet a polar bear there, even in winter, let alone summer, was far-fetched and we slept soundly in our tents without taking any precautions. We used a nearby hut for shelter from the weather. Last year I enquired about using that hut again and was told that it was no longer habitable: ‘due to damages made by polar bears’.

The west coast of
Spitsbergen is now thickly inhabited by bears in summer, as it was not then. In recent years they have killed all the eggs and goslings laid by barnacle geese on offshore islands: breeding success has been near zero. Something similar has been happening on Cooper Island off Alaska, where bears have predated black guillemot nests in recent years. In both cases, scientists are attempting to explain these changes in terms of bears being stranded on land by the loss of ice, but there never was summer sea ice (and rarely winter ice) on the west coast of Spitsbergen. Nobody with local experience is in any doubt that bear numbers have boomed in the region, thanks to the cessation of hunting in the 1970s, and that this rather than any change in ice cover locally is the chief reason for their more frequent encounters with bears. Yet the Polar Bear Specialist Group calls the trend in the Barents Sea bear sub-population ‘unknown’. Indeed, Dr. Susan Crockford has uncovered the astonishing fact that this entire population, which the Norwegian government has estimated as containing more than 2,000 animals, is officially listed as ‘data deficient’ on a new PBSG’s map, as is true for several Canadian ones that have also been counted.

The same organization claims that eight of the polar bear’s sub-populations are decreasing, but read its own website and you will find that this is based almost entirely on projections and mathematical models. The official data table and map says that two of these eight sub-populations are only ‘thought’ or ‘believed’ to be declining – entirely due to hunting; four are in decline only according to computer models, despite some claims by ‘traditional ecological knowledge’ (ie, locals) that they are thriving; one has more than doubled but is now said to be ‘currently declining’ because of crowding, not climate change; and only one showed a real decline. The latest data show that even that decline (in the
West Hudson Bay population) has probably recently been reversed.

In other words, the claim that polar bear populations are declining at all, let alone due to climate change, is a manufactured myth, designed for media consumption and with

very little basis in fact. That it works all too well is demonstrated by an episode in 2011 involving Sir David Attenborough. In a television series the brilliant television presenter, unwisely diverging from neutral natural history, had asserted that the polar bear is already in trouble. When challenged by Lord Lawson that ‘the polar bear population has not been falling, but rising’, Sir David responded. He was quoted by The Daily Telegraph as saying ‘Most [polar bear populations] are in decline and just one is increasing – for a number of factors – one being they have stopped hunting…Lord Lawson is denying what the whole scientific community is accepting and working at and it is extraordinary thing for him to do’.

Much as I admire and like both men, I have to say that the evidence suggests that Lord Lawson’s account is closer to the truth. The International Union for the Conservation of Nature estimated in 1966 that there were 10,000 polar bears in the world; in 2006, the same source estimated that the population had risen to 20,000-25,000 bears. Had Sir David examined the text on the PBSG’s website he would have found that all but one of the eight sub-population declines he cited were in fact based on ‘beliefs’ or future projections. As demonstrated by another recent mistake in another television series, this time an exaggerated claim for temperature change in
Africa, Sir David is not being well served by his BBC researchers these days.

Zac Unger documents in his recent book Never Look a Polar Bear in the Eye, how polar bear ‘decline’ is now a large and lucrative industry and in places like Churchill, Manitoba, organisations like Polar Bears International cynically use the imagined plight of the bears to raise money, and push propaganda at young people about changing their lifestyles and those of their parents.

We’re empowered to teach these kids how to make a difference. It’s an enormous responsibility. Saving the polar bear is in their hands,

an activist explains to Unger, having flown school children by helicopter to a bear-proof camp so they can emote by video-conference to schools across
America. As Attenborough once said:

All these big issues need a mascot and that’s what the polar bear is.

Yet as Unger discovered and Susan Crockford confirms, increasingly the local people in places like Churchill look on the carnival of tourists, journalists and scientists with bemusement, knowing full well that even there – in one of the most southerly polar bear populations of all – the evidence of a decline in numbers, or of the health of the bears, is threadbare or non-existent. How much more threadbare that evidence is farther north, where the bears’ greatest problem is usually too much ice and therefore too few seals, is poorly known. The ideal habitat for polar bears is first-year ice that lasts well into summer, when they feed on fat young seals. The fact that this ice thins or breaks up enough to allow seals to feed during the autumn keeps the seal population healthy. Four to five months of ice-free fasting in early autumn is not exceptional for polar bears and two to three months is quite normal. The recent trend in most of the
Arctic – no change in winter ice extent but a decline in late summer ice extent – has been towards exactly this ideal combination.

Many scientists have grown frustrated with the domination of the polar bear story by dogmatic propagandists and have begun to speak out. Susan Crockford is one of them: a zoologist who is independent of the alarm industry and therefore free to make up her own mind. In this valuable paper, she has done a fine job of documenting the actual facts of the case as far as they are known.

Matt Ridley
Global Warming Policy Foundation