1972 book explodes the myth of polar bears eating only seals near ice

Polar Bear Blog – Some Neat Stories About Polar Bears

[‘Encounters with Arctic Animals’ (1972)] The 18th century trader-explorer-hunter Captain George Cartwright came upon more than a dozen polar bears, scooping salmon out of a south Labrador river in the fashion of the great Alaska brown bears.
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‘At this time (when polar bears come ashore in summer), the bears switch from a wholly carnivorous to a predominantly vegetarian diet. It is rather surprising to see a polar bear, the world’s largest carnivore, sitting peacefully on an arctic meadow munching grass and sedges. This diet may be supplemented with seaweed, sorrel and other plants, with berries in fall, and in lemming years some polar bears methodically hunt these little rodents. Sometimes they raid colonies of eider ducks or snow geese, slurping eggs and catching the odd brooding bird. In the fall of 1967, a hunter near the coast of Hudson Bay saw a polar bear stalk on of his goose decoys with patience and skill. At ten years, it pounced but then it only got a mouthful of papier mache, it flattened every decoy in sight.’

Polar bears have always been resourceful and their varied summer diet is actually not a sign of distress or desperation, it is simply what bears have always done. The more history of animals you read, the more you realize we are making current decision based on a very narrow view of animal intelligence and adaptability.