What is a polar bear thinking?
Swims for days without touching land. Would still rather be lying down.
One tracked female swam continuously for nine days and around 690 km without hauling out. Polar bears are classed as marine mammals for exactly this reason - the swimming is not an emergency, it is part of how they live.
The rest is deliberate energy management. Hunting seals at a breathing hole means lying still for hours, and a bear that spends its day apparently doing nothing is running the most efficient strategy available.
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