A Farewell to Salmon?

Earth Island Journal, Spring, 2000 by Ron Sullivan

The small brown, battered fish found in most breeding farms barely resemble the long silvery torpedoes we know as the aristocratic Atlantic salmon.... Farm fish, the marine equivalent of domesticated cattle, are being bred in ever greater numbers while salmon in the wild have dangerously dwindled to an all-time low.

-- Marilyn Bauer, "Incredible Disappearing Salmon," Boston Globe

In addition to the usual litany -- dams, pollution, over-fishing and habitat loss -- wild Atlantic and Pacific salmon now face a new threat -- from fish farming. By 1998, the North American spawning run, once estimated at 2.5 million adult breeding fish, had fallen to an all-time low of 80,000. Farmraised salmon now outnumber wild salmon 50-to-one.

Bill Taylor, president of the Atlantic Salmon Federation, calls the salmon "a barometer for the health of the North Atlantic ecosystem.... The fact that our salmon populations are in freefall should signal to us that the health of our rivers and oceans is under siege."

Conservation measures such as catch-and-release fishing rules, commercial fishing bans and river cleanups, while partially successful in some areas, have failed to give salmon populations a significant boost. Even international agreements that halted fishing in the waters off Greenland and North America have failed to reverse the salmon's death spiral.

Last October, a joint report by the US Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) warned that, despite conservation measures, wild Atlantic salmon are in danger of extinction. Fewer Atlantic salmon are returning to spawn each year while large numbers of young salmon are not surviving in the rivers and the ocean.

Fish Farms vs. Wild Salmon

According to FWS biologist Paul Nickerson, the biggest threat to the survival of the wild Atlantic salmon comes from farm-raised salmon. "The aquaculture industry raises salmon of various origins," Nickerson notes, and when these fish escape "they pose several threats to wild populations."

Salmon farming is big business. The $900 million US seafood-farming industry accounts for $60 million worth of annual earnings in Maine alone. Nonetheless, the threat to Atlantic salmon is so severe that the FWS and NMFS have called for reducing water diversions to increase river flows, tighter restrictions on sport-fishing, and closer regulation of fish-farming.

In October 1999, in response to the FWS/NMFS report, US Interior Secretary Bruce Babbitt announced that he would nominate the Atlantic salmon for Endangered Species Act (ESA) protection. A Defenders of Wildlife lawsuit demanding an emergency ESA listing for the Atlantic salmon also spurred Babbitt's action.

The actual listing could take up to 15 months. Meanwhile, local governments -- along with the logging, sport-fishing, and cranberry- and blueberry-growing industries -- are raising strenuous objections. Maine Governor Angus King called Babbitt's ruling a "betrayal" that would cripple the state's aquaculture industry.

While fish farms provide an economic boost to coastal communities, aquaculture is no friend of the wild salmon. Fish-farming, like any farming, uses local resources: water, space, fuel and feed. As Michael V. McGinnis pointed out in a 1994 Natural Resources Journal essay, "hatchery production of salmon masks the decline of wild salmon, contributes to the genetic dilution and loss of wild salmon, and increases the competition for freshwater and ocean resources on which salmon depend."

Atlantic Salmon in the Pacific?

It may come as a surprise that fish farms on the Pacific coast do not raise Pacific salmon: They typically raise Atlantic salmon. When farmgrown salmon escape or are released into oceans and rivers, they compete with threatened wild populations. Escaped farm salmon may displace wild stock in their traditional spawning grounds. If they mate with wild salmon, they can dilute the genetic strength of wild salmon populations.

Because salmon-farm breed stock and fry are collected from many scattered locations, this can introduce genetic traits that are disadvantageous for the long-term survival of wild salmon. The smaller the wild population, the greater the threat.

Infectious salmon anemia (ISA) is an incurable disease caused by a virus that seems to mutate easily, complicating efforts to control it. Crowded fish-farm conditions facilitate the spread of the disease. ISA has been found in Atlantic salmon raised in both Atlantic and Pacific Coast fish-farms. ISA has caused millions of dollars in losses in Norway, Scotland and New Brunswick, Canada, where entire fish stocks had to be destroyed to prevent the further spread of the infection.

In October 1999, the Research and Environment Department of the Atlantic Salmon Federation confirmed that ISA-infected salmon from Atlantic fish farms had escaped and apparently spread the disease to the embattled wild salmon populations.

ISA first surfaced in the Norwegian salmon farming industry in 1984. An ISA epidemic swept Canada's east coast fisheries in 1996. ISA now threatens US fish-farms in Cobscook Bay, near the Canadian border.