Why the Polar Bear Is a Sea Animal That Can't Survive the Sea

By law, the polar bear is a marine mammal. Its scientific name, Ursus maritimus, means "the bear of the sea." It can swim for nine days without stopping. And yet the open sea is one of the most dangerous places a polar bear can be. In 2008, a collared female in the Beaufort Sea swam 687 km in nine days. When scientists caught her again two months later, they found out what that swim had cost her. This film follows that bear, a record-breaking dive off Svalbard, and a set of collar cameras on Hudson Bay that recorded something no one had seen before: a polar bear finding food in the open sea. Why can an animal built for the Arctic Ocean not live on it? The answer is not in how well it swims. It is in what a polar bear needs under its feet. We also travel to Southeast Greenland, where a population of polar bears has survived for centuries with sea ice for only a third of the year, and see what they prove about the rule. Sources: Durner G.M., Whiteman J.P., Harlow H.J., Amstrup S.C., Regehr E.V., Ben-David M. (2011). Consequences of long-distance swimming and travel over deep-water pack ice for a female polar bear during a year of extreme sea ice retreat. Polar Biology. Pagano A.M., Durner G.M., Simac K.S., York G.S., Amstrup S.C. (2012). Long-distance swimming by polar bears of the southern Beaufort Sea during years of extensive open water. Canadian Journal of Zoology. Stirling I., van Meurs R. (2015). Longest recorded underwater dive by a polar bear. Polar Biology. Stirling I., Richardson E., Thiemann G.W., Derocher A.E. (2008). Unusual predation attempts of polar bears on ringed seals in the southern Beaufort Sea. Arctic 61(1). Pagano A.M. et al. (2018). High-energy, high-fat lifestyle challenges an Arctic apex predator, the polar bear. Science. Blix A.S., Lentfer J.W. (1979). Modes of thermal protection in polar bear cubs at birth and on emergence from the den. American Journal of Physiology. Pagano A.M. et al. (2024). Polar bear energetic and behavioral strategies on land with implications for surviving the ice-free period. Nature Communications. Laidre K.L. et al. (2022). Glacial ice supports a distinct and undocumented polar bear subpopulation persisting in late 21st-century sea-ice conditions. Science. Atkinson S. et al. (2022). Aerial survey of the Western Hudson Bay polar bear subpopulation, 2021. Government of Nunavut report. #polarbear #arctic #wildlifedocumentary #seaice #marinemammals #animalfacts #nature #climatechange