Over the past several years there has been considerable controversy relating to salmon farming in saltwater. The potentially adverse effects of salmon aquaculture, especially of Atlantic salmon on wild Pacific salmon stocks, are genetic and ecological interactions, disease transmission including parasite infestations and the effects of therapeutic compounds used to control diseases and parasites. An example of the controversy is this year's "unprecedented declines" in returning adult pink salmon in the Broughton Archipelago off northeastern Vancouver Island. A report from the Pacific Fisheries Resource Conservation Council, a government-funded group in British Columbia, indicates that the decline may be due to sea lice transmitted from Atlantic salmon to vulnerable outmigrating juvenile pinks. This region contains the highest concentration of salmon farms on the British Columbia coast. The council recommends the closure of these farms during the coming spring period of pink outmigration.

In September 2001, the National Marine Fisheries Service's (NMFS) Northwest Fisheries Service Center (NWFSC) released a 125-page technical memorandum "The Net-pen Salmon Farming Industry in the Pacific Northwest". In June 2002, the NWFSC released an 83-page technical memorandum "Review of Potential Impacts of Atlantic Salmon Culture on Puget Sound Chinook Salmon and Hood Canal Summer-Run Chum Salmon Evolutionarily Significant Units" (ESUs). The threatened status, under the Endangered Species Act (ESA), of these two ESUs required a determination on whether this commercial activity would harm (represent a take under ESA) these ESUs, thereby decreasing their likely recovery in the wild. The 2001 document discusses the risks and uncertainties associated with salmon aquaculture in the Pacific Northwest. In addition to a brief history and regulatory aspects of salmon aquaculture in the state, this memorandum reviews and discusses the issues relating to:

• human health and safety; including organic toxicants farmed salmon might accumulate from their feed;
• salmon farming and the environment; including organic wastes, inorganic wastes, farm sediments and managing the environmental effects; and
• Atlantic salmon and local ecosystems; including potential genetic interactions (hybridization) between Atlantic salmon and Pacific salmon, disease transmission and epidemics and predation by Atlantic salmon and other social interactions.

NMFS's conclusions, based on the available evidence (literature reviews and ongoing research):
1) The degrees of risk and uncertainty "vary considerably from issue to issue"
2) The "Washington State regulation of the industry provides adequate protection to stocks of Pacific salmon listed under ESA"
3) "The operations can be managed to minimize risks to local salmon populations"
4) "There are legitimate issues associated with hatchery-reared salmon and trout that end up in natural ecosystems"

Read these two NMFS documents and derive your own conclusions on this controversial subject.

Each document can be ordered:

• from National Technical Information Service, 5285 Port Royal Road, Springfield VA 22161;
• by phone at 1-800-553-6847;
• by e-mail at orders@ntis.fedworld.gov;
• downloaded in a PDF format from http://www.nwfsc.noaa.gov/pubs/ by clicking on the appropriate title.