Endangered Species Act

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Endangered Species Act

The federal Endangered Species Act of 1973 (ESA) (16 U.S.C.A. §§ 1531 et seq.) was enacted to protect animal and plant species from extinction by preserving the ecosystems in which they survive and by providing programs for their conservation.

The act classifies species as either endangered or threatened. It defines an endangered species as one "in danger of extinction throughout all or a significant portion of its range" (§ 1532). A threatened species is one that is "likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range" (§ 1532). A current detailed listing of endangered and threatened animal and plant species is provided in the Code of Federal Regulations (see 50 C.F.R. §§ 17.11–.12). As of March 2003, the code listed approximately 1,260 endangered and threatened species (up from 1,000 in 1996). Between the years of 1995 and 2002, 12 species were removed from the list.

The ESA is administered by two agencies: the National Marine Fisheries Service, which designates marine fish and certain marine mammals, and the U.S. Fish and Wildlife Service, which has jurisdiction over all other wildlife. These agencies may list a species on their own initiative, or any interested person may submit a petition to have a species considered for listing. In either case, the act requires that the decision to include a species must be based solely on the "best scientific and commercial data available," following a review of the status of the species that takes into account any conservation efforts being made to protect the species (§ 1533 (b)(1)(A)).

If an emergency poses a significant risk to the well-being of a species of fish, wildlife, or plant, the secretary of the interior may bypass standard listing procedures and issue regulations that take effect immediately upon publication in the Federal Register. Emergency regulations remain in force for 240 days. To issue an emergency regulation, the secretary must publish detailed reasons why the regulation is necessary and notify the appropriate state agency in each state where the species is found (§ 1533 (b) (7)).

Critical Habitat

The ESA requires that at the same time the decision is made to list a species, the secretary of the interior must develop a recovery plan for the species and, with certain exceptions, designate the critical habitat of the species. Critical habitat consists of "the specific areas within the geographical area occupied by the species, at the time it is listed … on which are found those physical or biological features (I) essential to the conservation of the species and (II) which may require special management considerations or protection." Critical habitat must be designated on the basis of the best scientific data available and after taking into consideration the economic impact of the designation. An area may be excluded from designation if the benefits of the exclusion outweigh the benefits of the designation, unless the failure to designate will result in the extinction of the species (§ 1533 (b)(2)).

In June 1978 the Supreme Court ruled that provisions of the federal Endangered Species Act prohibited the Tennessee Valley Authority from completing the controversial Tellico Dam. The 6–3 decision was a victory for the snail darter, the tiny endangered fish whose spawning area in the Little Tennessee River would be ruined by the Impoundment of a lake. Tennessee Valley Authority v. Hill, 437 U.S. 153, 98 S. Ct. 2279, 57 L. Ed. 2d. 117, 11 ERC 1705, 8 Envtl. L. Rep. 20,513 (1978)(NO. 76-1701).

The issue of the economic impact of designating critical habitat was addressed in Bennett v. Plenert, 63 F.3d 915 (9th Cir. 1995). In Plenert, Oregon ranchers and irrigation districts sued regulators under the ESA over a proposal to change water flow at reservoirs in Oregon and California in order to protect the habitat of two endangered species, the Lost River sucker and the shortnose sucker. They claimed that the proposal did not take economic impact into consideration before designating critical habitat. The district court dismissed the suit. The U.S. Court of Appeals for the Ninth Circuit affirmed the dismissal, holding that because the ranchers and irrigation districts had no interest in preserving the fish under the ESA, they were not within the "zone of interest" protected by the act. As a result, said the court, they lacked standing (a legally protectable interest) to bring a citizen suit.


Once a fish or wildlife species is listed as endangered or threatened under the ESA, the act prohibits anyone from taking the species; plants are protected under separate provisions of the act. To "take" a species means to "harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct" (§ 1532 (19)).

The federal courts have disagreed about the term harm in the ESA definition of taking which includes the detrimental modification of a species' habitat. For example, the U.S. Courts of Appeals for the Fifth and Ninth Circuits had interpreted the taking prohibition to include habitat modification (Palila v. Hawaii Department of Land & Natural Resources, 639 F.2d 495 [9th Cir. 1981]; Sierra Club v. Yeutter, 926 F.2d 429 [5th Cir. 1991]). But the U.S. Court of Appeals for the District of Columbia Circuit, in Sweet Home Chapter of Communities for a Great Oregon v. Babbitt, 17 F.3d 1463 (1994), invalidated regulations that included habitat modification within the definition of taking. On appeal of the Sweet Home decision, the U.S. Supreme Court resolved this split, holding that habitat destruction that "actually kills or injures" an endangered or threatened species constitutes a violation of the ESA (Sweet Home, 515 U.S. 687, 115 S. Ct. 2407, 132 L. Ed. 2d 597). In 1999, the ESA published its final rule defining the term harm in the Federal Register (64 FR 607277).

Violations of the ESA can result in criminal penalties of up to one year in prison and $50,000 in fines. Civil penalties of up to $25,000 for each violation may also be imposed. Private citizens may bring actions against other individuals or government entities for violations of the ESA.

The ESA allows certain exceptions to prohibited activities. For example, the secretary of the interior may issue a permit for a taking of a listed species that is "incidental" to an otherwise lawful activity. The applicant must prepare a conservation plan specifying the probable impact of the taking and the steps the applicant will take to minimize the impact. In the early 1990s, the department of the interior relied on this exception when it began negotiating voluntary habitat conservation agreements with timber companies in the Pacific Northwest. Under these agreements, the landowners can set aside habitat for endangered or threatened species and, in return, avoid prosecution for the incidental taking of a species by Accidental Killing or other harm. By 1995, the agency had begun negotiating more than forty such plans, covering 5.4 million acres, in Washington and Oregon. For example, Murray Pacific Corporation, a timber company in Tacoma, Washington, negotiated an agreement to set aside 10 percent of its 54,000-acre tree farm and provide buffers to protect spotted owls, salmon, and other species. Plum Creek Timber Company, the second largest private landowner in the Northwest, developed a far-reaching plan to set aside up to 170,000 acres of habitat that was expected to help protect an estimated 284 species of wildlife, including grizzly bears, gray wolves, moles, fishers, and several different kinds of frogs, fish, and birds.

Experimental Populations

In 1982, the ESA was amended to allow the reintroduction of experimental populations of threatened or endangered species into their historic ranges without requiring compliance with many of the act's restrictions (§ 1539 (j)). Currently designated experimental populations are listed in the Code of Federal Regulations (see 50 C.F.R. §§ 17.81–.82). As of March 2003, 35 species were designated as experimental populations, including the red wolf and the gray wolf. The experimental population designation relaxed existing ESA regulations by allowing reintroduced species to be managed or controlled; for example, ranchers could kill reintroduced wolves that threatened livestock.

In the 1990s, the federal government began a program to restore an experimental population of gray wolves to Yellowstone National Park and central Idaho. The program projected the transfer of 90 to 150 Canadian gray wolves into Yellowstone National Park and central Idaho over three to five years. In early 1995, 29 gray wolves from Canada were released into Wyoming and Idaho. The release of the experimental population of gray wolves was controversial and created conflict and lawsuits between environmentalists and livestock ranchers. The goal of the wolf recovery program was to remove wolves from the endangered species list by 2002. This did not happen. As of March 2003, the gray wolf remained listed as a "dual status" species (both threatened and endangered) but delisted status was pending, based on taxonomic revisions.

Proposed Reform

In 1995, Congress, intent on rewriting the ESA to loosen restrictions on private landowners, imposed a Moratorium on all new-species listings and critical habitat designations. The moratorium, passed as a rider to the Emergency Supplemental Appropriations and Rescissions for the department of defense to Preserve and Enhance Military Readiness Act of 1995 (Pub. L. No. 104-6, 109 Stat. 73), prohibited Secretary of the Interior Bruce Babbitt from spending funds to identify and list any additional endangered or threatened species.

The 1995 freeze created a backlog of nearly 250 plants and animals awaiting decision on protected status under the ESA. In 1996, as part of an agreement on federal spending for the current fiscal year, Congress agreed to waive the moratorium, and the President bill clinton administration began resolving the backlog, focusing first on species facing immediate extinction, then on species that biologists determined would be most likely to recover if given full protection under the law.

In latter 2000, the National Marine Fisheries Service and the U.S. Fish and Wildlife Service jointly published their final policy, effective October 20, 2000, for the controlled propagation of listed species, pursuant to organized and approved recovery plans, or as necessary to prevent extinction of a species. As of March 2003, 561 distinct approved recovery plans were listed, some of which covered more than one species.

Endangered and Threatened Wildlife and Plant Species, 2003
Mammals Birds Reptiles Amphibians Fishes Snails Clams Crustaceans Insects Arachnids Plants
source: U.S. Fish and Wildlife Service, Threatened and Endangered Species System, Summary of Listed Species, 2003.
Endangered Species
Total 316 253 78 20 82 22 64 18 39 12 599
U.S. only 65 78 14 12 71 21 62 18 35 12 598
Foreign only 251 175 64 8 11 1 2 4 1
Threatened Species
Total 26 20 37 10 44 11 8 3 9 149
U.S. only 9 14 22 9 44 11 8 3 9 147
Foreign only 17 6 15 1 2

Further readings

Cheever, Federico. 1996. "The Road to Recovery: A New Way of Thinking about the Endangered Species Act." Ecology Law Quarterly 23.

Craig, Barbara. "The Federal Endangered Species Act." 1995. Advocate (Idaho) 38 (October).

Department of the Interior, U.S. Fish & Wildlife Service. 2003. "Delisted Species Report." Available online at <ecos.fws.gov/servlet/TESSWebpageDelisted> (accessed April 10, 2003).

——. 2003. "Experimental Populations." Available online at <ecos.fws.gov/TESS/Species Report/generate> (cited on April 10, 2003)

——. 2003. "Summary of Listed Species." Available online at <ecos.fws.gov/tess/html/boxscore/html> (accessed April 10, 2003).

"Endangered Species Act—Judicial Deference to Agency Decision." 1995. Harvard Law Review 109.

Moore, Robert C. 1995. "The Pack Is Back: The Political, Social, and Ecological Effects of the Reintroduction of the Gray Wolf to Yellowstone National Park and Central Idaho." Cooley Law Review 12.

Wolok, Mimi S. 1996. "Experimenting with Experimental Populations." Environmental Law Reporter 26 (January).


Environmental Law; Environmental Protection Agency.

West's Encyclopedia of American Law, edition 2. Copyright 2008 The Gale Group, Inc. All rights reserved.
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