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News from the National Academies
Date: Jan. 20, 2004
Contacts: Bill Kearney, Director of Media Relations
Patrice Pages, Media Relations Officer
Christian Dobbins, Media Relations Assistant
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202-334-2138; e-mail <news@nas.edu>

FOR IMMEDIATE RELEASE

Urgent Statewide Action Needed to Address
Serious Depletion of Atlantic Salmon in Maine

WASHINGTON -- Urgent actions are needed if the once-abundant Atlantic salmon in Maine are to be replenished, says a new report from the National Academies' National Research Council. These rehabilitation efforts are needed statewide to preserve Maine's population of the fish, which constitutes most of the Atlantic salmon population in the United States.

"The decline of Atlantic salmon populations in Maine has been pervasive and substantial over the past 150 years, bringing them close to extinction in recent years," said Michael T. Clegg, chair of the committee that wrote the report, and professor of genetics, University of California, Riverside. "Comprehensive, statewide action should be taken now to ensure their survival. And a formalized decision-making approach is needed to evaluate options, establish priorities, and coordinate plans for conserving and restoring the salmon."

Populations of Atlantic salmon have declined drastically, from an estimated half million adult salmon returning to U.S. rivers each year in the early 1800s to perhaps as few as 1,000 in 2001. Atlantic salmon were listed in 2000 as endangered under the federal Endangered Species Act. Despite the intentional introduction of more than 100 million hatchery-raised salmon and the escape of an unknown number of pen-raised salmon into the wild over the past 130 years, salmon populations have never been smaller. The wild North American Atlantic salmon remain clearly genetically distinct from fish bred in captivity, according to an interim report from the committee in January 2002.

Atlantic salmon are adapted to two very different environments. The young hatch and grow for one to three years in freshwater rivers and streams before migrating to sea. At sea, the salmon mature for two to three years and then return to the same streams to lay their own eggs. While many of the adults die after spawning, some migrate back to sea and make another return trip to spawn again.

If these migrating salmon are to survive, a program of systematic dam removal should start immediately, the report says. Dams on Maine's rivers used for mills and other purposes hinder the passage of adult and juvenile salmon and alter the rivers' habitat. Some of the dams have also outlived their economic usefulness. The report estimates removal costs to be between $300,000 and $15 million per year, assuming a cost ranging from $100,000 to $3 million per dam and the removal of three to five dams per year.

There is a high natural mortality after young salmon migrate from fresh water to the ocean. Sulfates and other chemicals from the atmosphere that alter the water chemistry of streams may be harming young salmon and increasing mortality among fish making the transition from fresh water to salt water. The addition of limestone to rivers and streams, known as liming, is a well-established procedure that has had considerable success in counteracting acidification in streams. It should be tried in some Maine streams on an experimental basis as soon as possible, the reports says. It is estimated that the initial cost of liming each stream would be around $100,000, with subsequent costs of $50,000 to $100,000 per year for each stream treated.

Despite Maine's heavy reliance on hatcheries to increase its salmon population, these facilities should be used sparingly, the report says. The focus of hatcheries should be to preserve the genetic diversity of remaining wild salmon populations by providing them with a secure place to grow if necessary. Stocking rivers with hatchery-raised salmon remains an unproven way to boost the fish population, the report adds, and additional research and scientific guidance are needed.

The committee also recommended that Maine avoid stocking its streams with salmon or nonnative fishes that may mate with or crowd out wild salmon, or out-compete them for food. Improved monitoring of water quality and better efforts to prevent farmed salmon from escaping also are needed. In addition, a comprehensive decision-analysis approach should be established to prioritize and coordinate efforts to restore the salmon. Fishing has historically been a major source of mortality for Atlantic salmon, and fishing for this species should continue to be prohibited in Maine, the committee added.

The study was sponsored by the National Fish and Wildlife Foundation. The National Research Council is the principal operating arm of the National Academy of Sciences and the National Academy of Engineering. It is a private, nonprofit institution that provides science and technology advice under a congressional charter. A committee roster follows.

Copies of Atlantic Salmon in Maine will be available later this winter from the National Academies Press; tel. 202-334-3313 or 1-800-624-6242 or on the Internet at http://www.nap.edu. Reporters may obtain a pre-publication copy from the Office of News and Public Information (contacts listed above).

[ This news release and report are available at http://national-academies.org ]


NATIONAL RESEARCH COUNCIL
Division on Earth and Life Studies
Board on Environmental Studies and Toxicology
and
Ocean Studies Board

Committee on Atlantic Salmon in Maine

M.T. Clegg* (chair)
Professor of Genetics
University of California
Riverside

Paul K. Barten
Associate Professor
Department of Natural Resources Conservation
University of Massachusetts
Amherst

Ian A. Fleming
Associate Professor
Coastal Oregon Marine Experiment Station, and
Department of Fisheries and Wildlife
Oregon State University
Newport

Mart R. Gross
Professor of Conservation Biology
University of Toronto
Toronto

Lewis S. Incze
Senior Research Scientist
Bioscience Research Institute
University of Southern Maine
Portland

Anne R. Kapuscinski
Professor of Fisheries and Conservation Biology
University of Minnesota
Minneapolis

Barbara Neis
Professor of Sociology
Memorial University of Newfoundland
St. John's, Newfoundland
Canada

Patrick O'Brien
Senior Research Scientist
Chevron Research and Technology Co.
Richmond, Va.

Nils Ryman
Professor
Division of Population Genetics
Stockholm University
Stockholm, Sweden

Peter E. Smouse
Chair
Department of Ecology, Evolution, and Natural Resources
Rutgers University
New Brunswick, N.J.

Jennifer L. Specker
Professor of Oceanography
University of Rhode Island
Kingston

Robert R. Stickney
Director
Sea Grant College Program, and
Professor
Department of Oceanography
Texas A&M University
College Station

Jon G. Sutinen
Professor
Department of Environmental & Natural Resource Economics
Unversity of Rhode Island
Kingston

RESEARCH COUNCIL STAFF

David Policansky
Study Director


* Member, National Academy of Sciences