Killer whales along the Norwegian coast have long classified as fish-eaters. New research shows that some of them also eat seals – and accumulate large amounts of harmful pollutants.
Research of killer whales in the southern Atlantic ocean and Mediterranean have shown that their blubber contains high levels of pollutants called PCB, whilst killer whales found along the Norwegian coast have been assumed to be healthy and at low risk from pollution. This is because when researchers took samples from nine Norwegian killer whales in 2002, they found lower levels of pollutants than other populations.
But now, a new study has shown that killer whales along the Norwegian coast also eat seals, and these seal-eating whales are really polluted. They have up to four times as high levels of the pollutant PCB in their blubber than other whales in the population that just eat fish, and twice as high levels of mercury in the skin.
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