Polar bears survived past warm periods in the Arctic, when sea ice cover was low, by scavenging on the carcasses of stranded large whales; however, this resource will likely not be enough to sustain most bear populations in the future when the Arctic becomes ice-free in summers

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Polar bears survived past warm periods in the Arctic, when sea ice cover was low, by scavenging on the carcasses of stranded large whales; however, this resource will likely not be enough to sustain most bear populations in the future when the Arctic becomes ice-free in summers