If sea lce are a natural part of the ecosystem, why are they considered a problem?
Before fish farms arrived on our coast, nature had a system to protect juvenile wild fish from the lice that were common on adult salmon. When wild adult salmon spawn in rivers, they break the life cycle of the sea lice. Sea lice cannot tolerate freshwater and as the adults enter their natal rivers, the lice are shed and die. The following spring when the young wild salmon migrate from the freshwater to the ocean, there are virtually no sea lice in their path. But salmon farms changed that – acting as unnatural reservoirs for parasite populations to over-winter. The chances of juvenile wild salmon encountering sea lice on their way to the open ocean are now greatly increased by the lice infested salmon farms located along the out-migration routes.
