John M. Anderson
Atlantic Salmon Federation, Scientific Advisor

Over the past 30 years Atlantic salmon in their natural range in Eastern North America have undergone a steep decline in numbers. In spite of many steps taken to regulate the harvest, in particular a virtually complete ban of the commercial fishery, the decline has continued. In the U.S. the Department of Interior proposed on November 17, 1999 that the salmon populations in eight rivers in Maine be classified as endangered under the Endangered Species Act (ESA). The State of Maine has opposed this action. The Atlantic Salmon Federation and Trout Unlimited have jointly filed a lawsuit in Washington, DC, to force an emergency listing under the ESA that would shorten the time for corrective action to be taken. In Canada, the Department of Fisheries and Ocean has submitted a request to the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) that the salmon in the 33 rivers comprising the so-called Inner Bay of Fundy Rivers be listed as endangered. Unlike ESA, COSEWIC has no regulatory power to require corrective action to be taken following its listing decisions. This gap is to be addressed by proposed legislation in the Canadian Parliament of a Species at Risk Act, with regulatory powers.

The continued decline in salmon numbers appears to be caused by increased mortality in the sea. Possible anthropogenic-based explanations are depletion of the salmon’s normal food source by commercial fisheries for forage fish, such as capelin, and exposure of juvenile salmon during their freshwater phase to the "endocrine disrupter" nonylphenol, which leads to mortality later in the marine phase. As for natural processes at work, there are several possibilities. These include predation by seals, disease, and large-scale oceanographic perturbations, in particular those involving temperature. Recent advances in acoustic telemetry, which for the first time allows the tracking of postsmolts many miles in the open ocean, hold promise for finding out where and when the as-yet unexplained increased marine mortality occurs.

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