Eli5 why are polar bears endangered

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So this has been bugging me for a long time, what has polor bear ‘hunting grounds’ shrinking got to do with them finding less food?

As the ice caps melt seal populations will have to move further into the ice to survive, and so less ice = less distance bears need to travel = less area for seals to hide

So shouldn’t polar bears bears be benefitting from global warming and seals facing extinction?

In: Earth Science

Less ice means less hunting ground which means less food. Moving further north doesn’t mean there will be adequate food for the whole species. If you took all the deer in the world and put them in a 10 square mile area, they would starve to death.

Polar bears also need the ice as places to stay, hibernate, give birth to pups, areas for Cubs to hone their hunting skills, etc., not to mention the rising temperatures goes against the selective pressures they’ve evolved to for millions of years (a thick coat; if you’ve ever seen an “Arctic” dog like huskies and they shed their coat in the summer, it’s so they can’t cook themselves to death during the summer, which polar bears can’t). Also, decreasing seal populations = less food = very damaging to a high mass animal (they are the world’s largest terrestrial carnivore). The reason why it’s an issue is because their functional diet breadth (basically how much stuff they eat) and the quality of their food (protein is high quality) means they need a lot of a specific range of foods, with them almost exclusively eating seals, and they need A LOT.

So, food scarcity + increasing temperatures + a thick coat acting as a greenhouse + habitat loss + their naturally high mass = conservation calamity.

Hope that helps!

Edit: structuring and facts I forgot to address – mind has been scrambled recently, so my thoughts haven’t been as clear as I’d like

Less hunting grounds means less food. Seals don’t just move to the ice, they die because they have to go further to rest, have more predators concentrated on them, etc.

Less ice means less breeding grounds too. Less places to make a den. Having to swim further and longer to get from patch to patch. More and more calories burned, and less taken in. A slow death by starvation.