Letter from top US seafood scientists about salmon farming

Don’t make decisions about salmon farming in “a climate fueled by fear and propaganda” warn top scientists in Washington.


As representatives of the scientific community, we are alarmed that the Washington state Legislature may take steps to eliminate an industry—salmon aquaculture—without understanding the ramifications of such an action or reviewing the overwhelming body of peer-reviewed science that exists regarding many of the concerns fueling this legislation.

We respectfully request that the members of the Senate and House of Representatives take into consideration this peer-reviewed science when voting on House Bill 2957, which would essentially halt Atlantic salmon aquaculture in this state forever.

As we see it, opposition to the farming of Atlantic salmon in Washington waters falls into four main categories:

  1. Genetic introgression (interbreeding);
  2. Competition for food;
  3. Competition for habitat; and
  4. Disease transmission.

While extensive research exists to allay such fears, and while the Washington Department of Fish and Wildlife has advised the state that they do not agree with the claims of salmon farm opponents, many in the legislature may not have had the benefit of reviewing this extensive peer-reviewed science, given the pressing deadlines of this session.

We would be willing to present in detail, with supporting documentation, such research; and we would be willing to have a full and frank discussion with interested members of the House and Senate about the enormous body of research that exists today.

In brief, however, we would like to present the facts and address some of the unfounded claims that have been made by salmon farming opponents:

  1. Interbreeding: Concerns about crossbreeding/ interbreeding farmed salmon (Atlantics) with wild Pacific stocks in the event of escapes are unfounded. Over the past 40+ years, hatchery scientists made many attempts to interbreed these different species; all were unsuccessful.
  2. Competition for food: Concerns about farmed salmon taking over habitat, if, and when, they escape, are unfounded as well. Again, peer-reviewed studies have shown convincingly that “captive” or pen-reared salmon have not learned how to “hunt” for food, simply because they are used to being fed on a regular timetable. Atlantic salmon, in particular, appear to be non-competitive with local species. Moreover, when the stomachs of “escaped” Atlantic salmon are examined, they have been found to be empty.
  3. Habitat invasion: Scientists to date have found no evidence of Atlantic salmon spawning on the West Coast of North America.
  4. Disease transmission: Salmon in an aquaculture setting are raised in a certified disease-free hatchery, then vaccinated against saltwater disease, and certified disease-free before they are moved to net pens. No example of disease transfer from farmed salmon to wild fish has ever been documented by any regulatory agency in the state of Washington.

We respectfully request that the Legislature review the existing scientific research that has been conducted by the Washington Department of Fish and Wildlife, NMFS, and the Canadian Department of Fisheries and Oceans. Until such time, we can and will make available key reference documents.

We call on our esteemed elected representatives to delay any decisions regarding the future of salmon farming in Washington until the scientific community, represented in this state by some of the world’s leading aquaculture and fisheries scientists and researchers in the fields of fish culture, genetics, nutrition, and fish behavior, has had an opportunity to present science in a clear and objective light— rather than in a climate fueled by fear and propaganda.

Finally, in writing this letter, we strongly urge Members of the House of Representatives and the Senate to not “throw out the baby with the bathwater” by dealing a fatal blow to an industry—salmon farming— that is now producing millions of metric tons of nutritious salmon, worth billions of dollars, around the world.



Linda A. Chaves

Senior Advisor on Seafood and Industry Issues, NOAA (retired)

NOAA National Aquaculture Coordinator (retired)

John Forster, Ph.D.

Former President, Stolt Sea Farm Washington, Inc.; Aquaculture career began in 1965

Established salmon farm in Port Angeles, 1984; Consultant to aquaculture industry (current)

Robert N. Iwamoto, Ph.D.

Director-Office, Management, and Information (retired), Northwest Fisheries Science Center, NOAA

Chief Science Officer (retired), Reverence LLC and Evaqua Farms, LLC

Aquaculture consultant, salmonid genetics

Conrad Mahnken, Ph.D.

NOAA National Aquaculture Coordinator (retired)

NOAA Manchester Laboratory Director (retired)

Washington Fish and Wildlife Commissioner (retired)