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According to a recent study by the University of Alberta,
parasitic sea lice are killing a population of young wild
pink salmon along Canada's west coast in alarming
numbers. The authors of the study say that the entire wild
population may be gone within eight years. With their
protective scales, adult salmon can safely harbour the
lice, but young salmon do not yet have the protective
scales, leaving them prone to deep, infection-prone
wounds left by the lice. Juveniles live in coastal waters,
which are normally far from parasite-carrying adults living
farther out to sea. Now, however, aqua farms are often
located in these same waters, destroying the young
salmon's safe haven. Scientists argue that fish farms
must be relocated or reduced, but so far, no government
regulations have been launched to this end.