| Salmon
that travel to Alaska’s lakes each year to spawn are filled
with harmful toxins known as PCBs. The PCBs accumulate in the
salmon as they feed in the ocean and could be harmful to bears,
eagles and humans who eat them.
The salmon, which die in the lakes after spawning, then decompose,
depositing the PCBs in the lakes’ sediment. The result
is that the lakes, which would otherwise be pristine, are
accumulating toxins at levels comparable to lakes near highly
industrial areas.
Further, commercial salmon fishing in the Northwest is being
threatened by the increasing popularity of farm-raised salmon.
Salmon farms are driving local fisheries out of business while
posing ecological dangers to the area. Escaped farmed salmon,
which are often contaminated with sea lice and viruses, pose
a threat to natural salmon populations and chemicals and pharmaceuticals
from the farms can damage the marine environment.
Nature
September 18, 2003
Science
Daily September 23, 2003
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