In Canada and Alaska, the consequences of global warming are being keenly felt by brown bears - but in different ways by different populations. Their survival depends mainly on the quantity of wild salmon available in the region, as it is the fruit of their catch that enables the bears to accumulate fat reserves for the winter. While salmon populations off Canada's Pacific coast continue to decline year after year, in the immense Bristol Bay in western Alaska, as well as on Kodiak Island, they are increasing considerably. The water temperature in the North Pacific is now ideal for salmon development. From Canada to Alaska, the documentary follows different bear populations over a two-year period.