This is an example of the Law of Unintended Consequences, which humanity, in its arrogrance about and ignorance of the natural world, stumbles over again and again.
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By JEFF BARNARD
The Associated Press
GRANTS PASS, Ore. – A team of Canadian scientists has found the most direct evidence yet that baby salmon pick up fatal infections of sea lice while swimming past salmon farms in British Columbia’s Broughton Archipelago, and that the more salmon farms the more baby salmon die.
“Before we knew there were potential problems,” said Martin Krkosek, a doctoral student at the University of Alberta who was lead author of the study released Monday by the American journal Proceedings of the National Academy of Sciences. “Now it is very clear we have severe problems here.”
In natural conditions, the adult salmon that carry the sea lice aren’t in the migration channels and rivers at the same time as young pink and chum salmon, so the little fish are not infested, said Mark Lewis, University of Alberta senior Canada research chair in mathematical biology, who oversaw the research.
But fish farms have changed that, raising hundreds of thousands of adults in floating net pens anchored year round in the channels where the young fish migrate. The young pink and chum salmon are only an inch long, and do not yet have scales to protect them from parasites, he said.