BBC: Scientists say that foxes in Arctic regions who feed on ocean prey are being exposed to dangerous levels of mercury.
On one Russian island where the population of foxes has crashed, the researchers believe the toxin has played a key role in the decline.
They say the findings could have important implications for conservation.
The data is published in the Journal, PLOS ONE.
Mercury levels in the world's oceans have doubled over the past 100 years, according to the UN, with more mercury...