Canadian polar bear guide Dennis Compayre has spent more than 20 years around Churchill, Manitoba, and his simple words in a 19 February CBC article promoting an upcoming CBC documentary special are clear: Western Hudson Bay (WH) polar bears are currently thriving.

Mother with triplet cubs, 31 October 2020. Dave Allcorn photo.

Compayre does not appear to be a global warming skeptic: he seems to accept the prophesy that the future is grim for these bears. However, if he hadn’t I’m certain he wouldn’t have gotten the job as guide for this Nature of Things documentary, hosted by Canada’s ultimate carbon dioxide doom-master David Suzuki. However, he is at least willing to tell the truth about what has been happening over the last four years (the time it took to film this documentary) with WH polar bears.

In his words, my bold:

“Regardless of the research papers you read in front of you, you can gather more information by just actually looking at the bear and seeing what condition they’re in.

And they have put on a lot of fat and they’re happy and they’re strolling along like they don’t have a worry in the world…

I don’t see any change in the bears’ population. The bears are healthy, maybe even healthier.”

Read the rest here: Campayre tries his best to give an honest portrayal of the situation in recent years for polar bears around Churchill and still appease his paymasters.

His statement about the condition of the bears is similar to the one I’ve been making for the last six years, based on testimonials like his and fellow Churchill guide from the short-lived Smithsonian Channel TV series Polar Bear TownKelsey Eliasson, watching the bears on the Explore.org live cam in Wapusk National Park, admissions from an occasional scientist, and reports from Churchill’s Polar Bear Alert Program – as well as the published scientific literature (Crockford 2021).  Western Hudson Bay polar bears have had very good ice conditions since 2014 and have been in excellent condition: even the very late freeze-up in 2016 didn’t have an negative impact because they were very well fed when they came off the ice months earlier.

Unfortunately, Compayre accepts the bizarre opinion of biologist Robert Rockwell that polar bears get a substantial benefit from eating land-based foods. According to a CBC companion piece, Rockwell not only insists polar bears will survive by eating terrestrial foods if the dire predictions of climate scientists ever come true but that the bears also survived the Eemian Interglacial more than 100 thousand years ago by foraging on land. It is apparent that this view is included in the Kingdom of the Bears film in which Compayre appears as a guide even though it is a fringe view that does not make evolutionary sense and has little plausible evidence to support it.

Polar bears evolved to live on a diet dominated by fat and their entire life history depends on that energy-intensive food source and sea ice availability. Yet, Rockwell states that there was no Arctic ice at all during the Eemian (my bold):

“Biologist and ecologist Robert Rockwell says for the 130,000-year estimate, which coincides with the Eemian interglacial period, there was no ice in the Arctic at all.

“[Polar bears] went through a long period of several thousands of years in an ice-free world,” Rockwell says. “There were polar bears, but they weren’t on ice. They were just in the North.”

This is nonsense: as I’ve explained before in a post with abundant references, there was much reduced summer ice during the Eemian Interglacial (with ‘ice-free’ summers that still left about 1mkm2 of ice in the far north), no winter ice in the Bering Sea, and likely such a short season of ice cover for Hudson Bay that polar bears would not have been able to live there year round. There is no evidence polar bears lived in Hudson Bay during this time: Rockwell simply assumes that they did and therefore had to eat terrestrial foods to survive.

However, what we’ve learned about the bears in recent years is that they are far more willing and able to more from areas they have occupied for centuries if sea ice conditions make living there too difficult. Bears would not have tried to subsist on terrestrial foods if they had no ice from which to hunt seals in the spring: they would simply have moved north, probably into Foxe Basin, where ice conditions were better. This is what bears around Svalbard have done in recent decades when sea ice levels dropped: females shifted to making maternity dens on the pack ice to the north or on the archipelago of Franz Josef Land to the east where ice has been more consistently available – but returned to the ice around Svalbard in spring to hunt seals.

In other words, there is no evidence whatsoever that polar bears survived the Eemian Interglacial in Hudson Bay by adopting a ‘terrestrial existence’ of living off eggs and caribou.  There is also no evidence that the bears survived by scavenging whale carcasses rather than seals, as other researchers have suggested. We now know that primary productivity increases with less summer ice (Crockford 2021), providing the entire Arctic food chain – including polar bears – with more to eat. There is no evidence that seals were scarce in the Eemian – and on the contrary, it is highly likely that with less summer ice than we have now, seals would have done very well – as they are now – because of the increase algae growth. Bears may have been distributed differently than they are today but there is no evidence that their numbers were substantially reduced.

If there was truly no ice in the Arctic at any time of year, polar bears would become extinct. But that hasn’t happened in millions of years and even the most pessimistic climate models don’t predict that scenario by 2100.  Western Hudson Bay polar bear are indeed thriving despite recent declines in Arctic sea ice and this is a conundrum that polar bear specialists are unwilling to admit.

References

Crockford, S.J. 2021. The State of the Polar Bear Report 2020. Global Warming Policy Foundation Report 48, London. PDF here.

via polarbearscience

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February 28, 2021 at 01:52AM