We rather thought polar bears had vanished as climate change poster beasts because they stubbornly failed to vanish in real life. But now we hear that “Norway's polar bears turn to inbreeding, cannibalism to survive climate change, studies show”. That’s really disgusting. And rather hard to believe. But ok we’ll click on the link anyway. And by the time we get from the headline to the “deck” beneath it, things are already calming down, with “A recent study found that the genetic diversity of bears in Norway's Arctic has decreased by 10 per cent, as sea ice loss causes habitat fragmentation”. A 10% drop in genetic diversity isn’t quite the same as getting frisky with your sister then eating her.
Nor is something that’s been going on for a long time exactly breaking news. And the story also does the usual climate change time travel thing, saying “Scientists have noted that ‘rapid sea ice loss in the Arctic Barents Sea’ has led to the loss of 10 per cent of genetic diversity in the polar bear population of Norway’s Svalbard Archipelago, between 1995 and 2015, states the study, published by The Royal Society journal on Sept. 8.”
So this is one of those effects of climate change that was already major, even catastrophic, as well as revolting, starting in … 1995. When Arctic ice was on a downswing from the natural cyclical peak of 1979, but hardly to where it would bottom out in 2012 before starting to rebound. Not to mention where it got to 6,000 years ago.
The extent of the disaster is also a little hard to faint over. “Examining the DNA of 622 polar bears in the [Svalbard] archipelago, they found that the group had grown more genetically distinct from polar bears seen at other areas in the Arctic. Simultaneously, the polar bears had also grown more genetically distinct from the polar bears found at other sites in the Arctic, indicating the bear populations found in the same location are becoming more genetically similar.” Which could happen if a group of animals lives together for a while. Indeed it’s hard to imagine it not happening. All over the place. Constantly. Since the first herd of Iguanodon wandered down a valley into an isolated meadow.
Surely you’d find the same thing with lions. Or with that process whereby the scary brown grizzly bear hived off the even scarier white polar bear with its, um, greater genetic distinction manifested in stuff like pale fur. (Something the settled science says happened between 70,000 and 1.5 million years ago.) Indeed, what would be really weird is if the extent of DNA divergence never changed as populations moved about, expanded, contracted, blundered into cul-de-sacs, jumped out again and so forth.
Still, the story says this one is different because of climate change: “Declining sea ice coverage, the study explained, leads to habitat fragmentation, forcing polar bears to mate with others within a smaller area, resulting in inbreeding.” But even this claim is pretty wobbly since we now know that polar bears are pretty versatile beasts who do not depend massively on extensive sea ice to hunt. And we know this by studying bears in (drum roll please) the Svalbard area.
OK, OK, you’re saying, this is a bit lewd. But we want gore. Not Al Gore. Cannibalism gore. That headline promised us blood all over the place and we want it now.
Well, here it is: “A second study, released in April, found that climate change has severely disrupted the dietary habits of the polar bear population, forcing them to prey on seabirds and eggs instead of seals. However, due to lack of experience, most bears observed were not ‘efficient’ seabird egg predators, the study found, noting that instead of visiting multiple nests, bears would often visit the same empty nest multiple times.”
Of course you might object that your dog will come into the kitchen and sniff at a plate he already licked for reasons unrelated to a forced change of diet. Or that a polar bear might check the same stretch of ice for seals repeatedly or something. But still, that was just a bear eating an egg that wasn’t there. When do we get bears eating bears?
Relax. Here it is: “In some areas of the Arctic suffering from a lack of food sources, bears have become increasingly cannibalistic, experts say. The disappearing sea ice, Russian scientist Ilya Mordvintsev said, has forced the bears onshore instead of in the water hunting seals, consequently turning to food sources on land.” But at the risk of seeming anti-polar bear, or stereotyping Ursus maritimus, we have the impression those things are the apex predator’s apex predator and as in the old joke about what a polar bear eats, it’s anything he wants including another polar bear. And worse.
Wikipedia confirms that “The polar bear (Ursus maritimus) is a hypercarnivorous bear”, a term here meaning pretty much what you’d expect of this blanched version of the ferocious grizzly. And more. “Polar bears may attempt to consume almost anything they can find” including every kind of meat on legs, wings or fins but also “hazardous substances such as styrofoam, plastic, car batteries, ethylene glycol, hydraulic fluid, and motor oil.” And other polar bears?
Oh yeah. The story states that “’Cases of cannibalism among polar bears are a long-established fact, but we’re worried that such cases used to be found rarely while now they are recorded quite often,’ Mordvintsev said at a presentation in St. Petersburg. ‘We state that cannibalism in polar bears is increasing…. In some seasons, there is not enough food and large males attack females with cubs.’”
All because of climate change. Or not.