In Scotland an entire river was deliberately poisoned to exterminate diseased fish populations that were infected by farmed fish. Nothing in the industry has stirred up more controversy that the research to genetically-modify salmon. Dr. David Suzuki states his opinion that the potential ramifications of genetic modification are too unstudied to allow these fish to be farmed where they might escape into the natural environment. Although transgenic salmon are supposed to be sterile, he says the chances are too high that some of these fish can reproduce. Our camera crew will also visit salmon farms using techniques that greatly minimize some of the potential impacts of salmon aquaculture including an operation in the state of Washington raising salmon in floating pools sealed off from surrounding waters.
Wastewater is filtered before pumped back into the sea.
Operations like these are more expensive to build and more expensive to operate, but critics of the industry acknowledge they are a step in the right direction. Because it takes five pounds of ocean fish to generate each pound of farmed salmon, Jim Fulton points out that salmon aquaculture, under the best of circumstances, represents a net loss of marine resources. In light of the ongoing debate over marine aquaculture, most marine scientists believe the best way to take pressure off marine fisheries is to change the ways fisheries operate. Program 3 examines some of the most promising efforts being made to restore capture fisheries and to develop forms of aquaculture that raise fish and shellfish that require fewer marine resources.