Posted onNovember 14, 2023|Comments Off on Walrus and polar bear population size changes in the N. Atlantic over the last 20k years
This is a lesson in how to assess the potential worth of scientific papers. One of two similar Arctic evolution studies got media attention, at least in Canada — about the polar bears, of course — but in my opinion the walrus research conclusions are much better supported, less biased by climate change rhetoric, and lack the hubris present in the polar bear paper.
Both studies use similar sample sizes for the regions they had in common (North Atlantic) and used computer models to determine genetic diversity and population size changes since the LGM. However, the tone of the walrus paper was less emotionally-charged and the caveats of the work were appropriately stated. In my opinion, papers like the polar bear example contribute to eroding the public’s trust in science.
The last Ice Age peaked between about 27,000 and 19,000 years ago. At this time the Arctic was buried under kilometers of glacial ice sheets, and so marine mammals were pushed southwards to areas of ice floes and more open water. Walrus survived in some areas of the Atlantic located further to the south, and as soon as climates warmed again, the ice edge retreated and walrus populations pushed quickly northwards again. This combination of warming and climate-driven dispersal led to local walrus populations becoming more genetically differentiated. Walrus study, Lund University press release 27 September 2023
Posted onNovember 8, 2023|Comments Off on Polar Bear Evolution pre-Christmas book sale: discounts on all formats!
I have reduced prices on all formats of my Polar Bear Evolution book for four weeks starting today (8 November-6 December 2023), in time for holiday gift-giving. The ebook version has the largest price reduction (60% of regular price, to US$17.40) but the other discounts are also substantial. This sale is a time limited offer: don’t miss out! Links below.
The author of Polar Bear Evolution, Susan Crockford, is a good, credentialed scientist. Her writing is clear; her thinking is also. She has a broad understanding of biology and an informed paleo perspective. Crockford condenses a very large literature on polar bear biology and evolution in this book which will help readers understand the science related to the evolution of an Arctic species. Perhaps the most important aspect of this book is its synthesis of information from the fields of wildlife biology, molecular evolution, paleontology, and climate. Her original ideas and hypotheses on thyroid hormone’s role in evolution are very important and add a credible mechanism of phenotypic change which complements the literature on molecular genetic evolution. Polar Bear Evolution is an important contribution to science and its application in evolutionary biology and wildlife biology. Matthew A. Cronin, Ph.D.
Available at the links below (others also available):
Posted onSeptember 25, 2023|Comments Off on Evolution Earth documentary comments on polar bear survival & adaptation: let’s see how they do
Just a heads-up that this week, PBS in North America will broadcast the “polar” episode of a new documentary called “Evolution Earth.” In my area, it’s scheduled for Wednesday, September 27 at 10:00 PM. It remains to be seen whether this is really about evolution or (given those involved in its production) simply more climate change propaganda similar to that promoted by Attenborough, but I intend to watch and report back.
About the Show: “Evolution Earth embarks on a global expedition to reveal the animals keeping pace with a planet changing at superspeed. Heading out across the globe to distant wilds and modern urban environments, five episodes track how animals are moving, using ingenuity to adapt their behavior, and even evolving in unexpected ways.
…We follow heart-warming tales of resilience that redefine our understanding of evolution, and hint at how nature can show us a path towards a sustainable future for Planet Earth. The series is narrated by Dr. Shane Campbell-Staton, who guides us through each episode in an intimate narrative style, drawing on his background as an evolutionary biologist.”
Episode 4 | Ice “At the planet’s frozen extremes, shifts in animal movement and behavior reveal vital information about our future world. Examine polar bears in the Arctic, penguins in Antarctica and other animals surviving in icy worlds.“
UPDATE 27 September 2023: Well, as I expected, this show was full of Attenborough-style nonsense about starving polar bears waiting for sea ice to form along Western Hudson Bay, the bears presented as “canaries in a coal mine” indicators of climate change, with an activist scientist saying she’s “pissed” about climate change. They used charts of the very distinctive pattern of sea ice formation that took place in November 2020 to illustrate how freeze-up was “later and later each year” even though 2020 was one of the earliest freeze-ups on record (bears were successfully hunting from shorefast ice as early as 30 October). A waste of 15 minutes: I couldn’t bear to watch what they did with the penguins.
Posted onSeptember 22, 2023|Comments Off on 17 years of near-zero trend in September sea ice demolishes claim that more CO2 means less sea ice
If the hottest year ever can’t precipitate ‘ice-free’ conditions in September, what’s it going to take? Arctic sea ice failed to nose-dive again this year, undoubtedly disappointing expects who have been anticipating a ‘death-spiral’ decline for ages. Arctic sea ice hit its seasonal low sometime around mid-September this year and although the precise value hasn’t been published, the average September ice coverage will likely be about 4.2 mkm2 once it gets announced in early October.
This means we have now had 17 years of a near-zero trend for September sea ice, extending the nearly-flat trend NSIDC sea ice experts acknowledged four years ago. This surely busts a huge hole in the prevailing concept that more atmospheric CO2 causes less summer sea ice. Note that CO2 levels measured in August 2023 were 419.7 parts per million (ppm), compared to 382.2 in August 2007, a rise of 37.5ppm with no corresponding decline in summer sea ice (and vs. 314.2 ppm in 1960). Measured in metric tons, CO2 emissions due to fossil fuels rose from 31.1 billion in 2007 to 37.1 billion in 2021 (last year of data), again with no corresponding decline in summer sea ice.
Posted onAugust 31, 2023|Comments Off on New study that claims it can directly link GHG emissions to polar bear cub survival is poppycock
A global warming miracle has happened. While no scientist worldwide has ever drawn a straight line between greenhouse gas emissions and population declines in a species considered at risk due to climate change, a new paper just published in Science Magazine claims to have performed this unlikely feat for polar bears. It’s called “Unlock the Endangered Species Act to address GHG emissions.”
Note this analysis has not been peer reviewed: as a “Policy Forum” contribution, it’s considered by the journal to be a public interest commentary, not a research paper.
One might be forgiven for asking whether this work represents solid, reproducible science or simply well-timed, sciency-looking rhetoric ready-made for the litigious Center for Biological Diversity to pressure the US government to increase protections for polar bears before the 2024 US election. It is surely no coincidence that this paper made its appearance near the seasonal low for Arctic sea ice as well as during the 15-year anniversary of the ESA listing of polar bears as ‘threatened’ and the 50th anniversary of the ESA itself.
Moreover, knowing this paper was in the pipeline might explain why the 2022 government report on the most recent Western Hudson Bay polar bear decline, which I discussed yesterday, has been kept secret for so long: the results of that report are cited in this new Science paper as supporting evidence that sea ice declines are responsible for recent population declines, which Reuters said in December was clearly not the casefor the period 2017-2021.
Posted onAugust 30, 2023|Comments Off on W. Hudson Bay polar bear numbers declined 27% in 2021 but not because of missing ice: secret paper
As will become apparent tomorrow, Western Hudson Bay polar bear numbers apparently declined 27% between 2017 and 2021 but not because of sea ice loss. This fact, gleaned from a secret government report leaked to the media, emerged just before Christmas last year and spread around the world. I commented on it here at the time.
It will also be apparent tomorrow why that government report is still unavailable. Thursdays are when the big two science magazines publish their papers, which means associated news stores promoting preferred narratives are embargoed until then. Stay tuned.
Posted onAugust 16, 2023|Comments Off on Conservation officers misleading the public about polar bear problems in Churchill
Canadian government-funded media outlet CBC ran a story this morning about problem polar bears in the town of Churchill, Manitoba, the self-described “Polar Bear Capital of the World” that contains some very misleading statements from Manitoba Conservation officers.
Breakup of sea ice on Hudson Bay was earlier this year than it has been in more than a decade (17 June) and some people are trying to hype the significance of this phenomenon to support a tenuous link to human-caused climate change, even though bears out on the ice this spring were reportedly in good condition and one of the problem bears captured on 8 August was also in good condition (a male weighing 910 lbs, photo above). Unfortunately, reports for similar early breakup years in the early 2000s have not been made public. However, I’ve been keeping track of these Polar Bear Alert Program Reports since 2015 and have read the available literature about their history: these records simply do not corroborate the statements in this CBC account.
Posted onAugust 8, 2023|Comments Off on Climate activists are silent on polar bears because their doom-mongering blew up in their faces
A Grist article last week pandered to activist polar bear specialists over their failed climate change agenda as it tried to minimize why the climate movement doesn’t talk about polar bears anymore. Apparently, the Arctic icon has “largely fallen out of fashion” through “overexposure” resulting in polar bear images invoking “cynicism and fatigue.” But that isn’t really true, is it?
Thriving populations in the Chukchi Sea and elsewhere amid low summer ice levels have busted the myth that polar bears need ice year-round.
Andrew Derocher was also allowed to repeat, unchallenged, the ridiculous narrative he and his activist supporters have peddled before, that insists the polar bear had become a climate change icon by accident rather than design, a lie I addressed in detail last year. Some excerpts from that 2022 post are copied below.
Yet contrary to predictions, which insisted that protracted poor ice conditions in summer would inevitably result in catastrophic rates of starvation and death (Amstrup et al. 2007; Crockford 2017, 2019), polar bears in the Svalbard region have so far not had any documented any harm to their health or population size. In fact, field data show bears in Svalbard are in better condition than they were in the late 1990s (Lippold et al. 2019), almost certainly due to the documented increase in primary productivity that has resulted from longer ice-free summers since 2003 (Frey et al. 2022; Crockford 2023).