Endangered Species:

Fish and Wildlife Service Uses Best Available Science to Make Listing Decisions, but Additional Guidance Needed for Critical Habitat Designations

GAO-03-803: Published: Aug 29, 2003. Publicly Released: Sep 29, 2003.

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Recent concerns about the U.S. Fish and Wildlife Service's (Service) endangered species listing and critical habitat decisions have focused on the role that "sound science" plays in the decision-making process--whether the Service bases its decisions on adequate scientific data and properly interprets those data. In this report, GAO assesses the extent to which (1) the Service's policies and practices ensure that listing and critical habitat decisions are based on the best available science and (2) external reviewers support the scientific data and conclusions that the Service used to make those decisions. In addition, GAO highlights the nature and extent that litigation is affecting the Service's ability to effectively manage its critical habitat program.

The Endangered Species Act requires the U.S. Fish and Wildlife Service to identify, or "list," species that are at risk of extinction and provide for their protection. The act also generally requires the Service to designate critical habitat--habitat essential to a species' conservation--for each listed species. The Service must use the best available science when making listing and critical habitat decisions. The Service's policies and practices generally ensure that listing and critical habitat decisions are based on the best available science. The Service consults with experts and considers information from federal and state agencies, academia, other stakeholders, and the general public. Decisions are subject to external "peer review" and extensive internal review to help ensure that decisions are based on the best available science and conform to contemporary scientific principles. External reviews indicate that the Service's listing and critical habitat decisions generally have scientific support, but concerns over the adequacy of critical habitat determinations remain. Listing decisions are often characterized as straightforward, and experts, peer reviewers, and others generally support the science behind these decisions. Critical habitat designations, on the other hand, are more complex and often require additional scientific and nonscientific information. As a result, peer reviewers often expressed concern about the specific areas designated, while other experts expressed concerns about the adequacy of the data available to make designations. The Service's critical habitat program has been characterized by frequent litigation. Specifically, the Service has lost a series of legal challenges that will require significant resources for the next 5 fiscal years to respond to court orders and settlement agreements for designating critical habitat. As a result, the Service is unable to focus resources on activities it believes provide more protection to species than designating critical habitat. While the Service recognizes that it has lost control of the program, it has yet to offer a remedy. Without taking proactive steps to clarify the role of critical habitat and how and when it should be designated, the Service will continue to have difficulty effectively managing the program.

Recommendation for Executive Action

  1. Status: Closed - Implemented

    Comments: Since 2012, the Fish and Wildlife Service (Service), in collaboration with the National Marine Fisheries Service, has issued policy and guidance related to designating critical habitat for listed species and to clarify the role of critical habitat. For instance, in 2012, the Service published regulations that clarified practices for providing the public with the geographic coordinates from which critical habitat designation maps are generated. In 2016, the Services published three additional rules intended to clarify, interpret, and implement portions of the Endangered Species Act concerning, among other things, the procedures and criteria used for designating and revising critical habitat, such as revising the definition of "destruction or adverse modification of critical habitat."

    Recommendation: Because the Service's critical habitat program faces serious challenges, the Secretary of the Interior should require the Service to provide clear strategic direction for the critical habitat program, within a specified time frame, by clarifying the role of critical habitat and how and when it should be designated, and recommending policy/guidance, regulatory, and/or legislative changes necessary to provide the greatest conservation benefit to threatened and endangered species in the most cost-effective manner.

    Agency Affected: Department of the Interior


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