Listing Distinct Population Segments of Endangered Species: Has It Gone Too Far?

November 18, 2000, the U.S. Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS, and together with FWS, the Services) promulgated a final rule listing a "distinct population segment" (DPS) of Atlantic salmon in the Gulf of Maine as an endangered species under the federal Endangered Species Act (ESA). 65 Fed. Reg. 69,459 (Nov. 18, 2000). The rule, which became effective on December 18, 2000, identifies and protects Atlantic salmon stocks in eight Maine rivers as the Gulf of Maine DPS. This highly controversial decision illustrates several unique and challenging issues that arise when the Services seek to apply their ESA listing authority to DPSs, including applying the DPS listing authority across international boundaries, treatment of genetic information, and identifying appropriate, scientifically defensible criteria for identifying DPSs. Many parties participating in the listing process have raised significant questions about the criteria and the quality and adequacy of the biological information used to support the conclusion that restoration stocks of Atlantic salmon in these rivers are sufficiently unique or discrete so as to qualify for listing. Although the ESA has frequently been touted as one of the most powerful environmental laws ever enacted in the United States, it does contain restrictions and limitations on how it can and should be used. One