Yet another study details the inevitable demise of the polar bears

It's been a while since we had any dire prognostications about the possible fate of the polar bear, but they are a perennial phenomenon, usually accompanied by less-than-scientific anecdotal refutations along the lines of "well, I saw one just the other day, they must be fine!"
But now we have another such dire prognostication. This one, just published in Nature Climate Change journal, suggests that continuing climate change will result in the elimination of most polar bear populations as early as 2100, with the last remaining populations expected to cling on to the Queen Elizabeth Islands in Canada's far north. Many polar bear populations are expected to start experiencing reproductive failure as early as 2040 under the business-as-usual model, and even if greenhouse gases are mitigated to a moderate extent, most will be feeling the effects by 2080.
Polar bears, now reduced to about 26,000 individuals worldwide, are unable to find enough sustenance for their huge bodies on land, and are forced to venture out onto the sea ice to hunt. As climate change reduces the extent and the stability of sea ice, the bears find it increasingly difficult to catch their prey (mainly seals) from ice floes. If forced to fast for too long, the reproductive capacity of the animals will suffer, and their numbers will start to decline rapidly.
The study is very conservative in its assumptions, assuming energy uses and starting points that are probably unrealistically optimistic, so the actual effects could occur even earlier than the study predicts. We will wait for the inevitable push-back from Inuit hunting guides and tourist operations, but the study's authors suggest that polar bear managers and other stakeholders should be looking into contingency plans. Like, now.