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Friday, February 11, 2011

The Endangered Species Act: A Primer

M. Lynne Corn
Specialist in Natural Resources Policy

Kristina Alexander
Legislative Attorney

Eugene H. Buck
Specialist in Natural Resources Policy

The Endangered Species Act (ESA, P.L. 93-205, 87 Stat. 884. 16 U.S.C. §§ 1531-1544) has a stated purpose of conserving species identified as endangered or threatened with extinction, and conserving ecosystems on which they depend. It is perennially controversial because the protections provided can make it the visible policy focal point for underlying situations involving the allocation of scarce or diminishing lands or resources, especially in instances where societal values may be changing. In response to past controversies, Congress has repeatedly considered minor amendments and major changes to the act, and various committees have stated their intention to do so again in the 112th Congress.

The purpose of the report is to describe the major features and controversies of the ESA as background for consideration of possible amendments in the 112
th Congress. The major features of ESA and related controversies are briefly summarized as follows: 
  • ESA retains its authorities even though its authorization expired in 1992, and funds may be and have been appropriated in the absence of a current authorization. 
  • ESA’s principal parts are the listing and protection of species, designation of critical habitat and avoidance of its destruction, and consultation by federal agencies regarding actions that may harm listed species. Each of these three principal parts is discussed in detail. 
  • Dwindling species are listed as either endangered or threatened according to assessments of the risk of their extinction. Once a species is listed, legal tools are available to aid its recovery and to protect its habitat. 
  • ESA has broad provisions for citizen suits to enforce the act, and lawsuits have played a major role in enforcement and interpretation of many, or perhaps most, of the act’s provisions. 
  • ESA has provisions for exemptions from the act for agency projects, but the provisions are little used for a variety of reasons. 
  • The act is administered primarily by the Fish and Wildlife Service, and by the National Marine Fisheries Service for certain marine and anadromous species. 
  • ESA is the implementing legislation for U.S. participation in the Convention on International Trade in Endangered Species. 
  • ESA often becomes controversial even where a particular species is not the focus of a controversy but a symptom of it.

Date of Report:
February 1, 2011
Number of Pages: 30
Order Number: RL31654
Price: $29.95

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