Endangered Species Act, United States

Source: Crs

The Endangered Species Act (ESA) protects species identified as endangered or threatened with extinction and attempts to protect the habitat on which they depend. It is administered primarily by the Fish and Wildlife Service and also by the National Marine Fisheries Service for certain marine and anadromous species. 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. The ESA can become the visible focal point for underlying situations involving the allocation of scarce or diminishing lands or resources, especially in instances where societal values may be changing, such as for the forests of the Pacific Northwest and the waters in the Klamath River Basin. This report discusses the major provisions of the ESA, both domestic and international, and also discusses some of the background issues, such as extinction in general, and the effectiveness of the statute.

An amplified discussion is provided on four aspects of the ESA and its implementation that have raised concerns and promoted debate — listing species, designating critical habitat, consulting on projects, and exempting projects. This report provides much of the issue context for understanding individual legislative initiatives discussed in '''CRS Report RL33468''', The Endangered Species Act (ESA) in the 109th Congress: Conflicting Values and Difficult Choices. This report will be updated as circumstances warrant.

The Endangered Species Act: A Primer

The Endangered Species Act (ESA) receives significant congressional attention. The associated power and reach of its comprehensive protection for species identified as endangered or threatened with extinction has ignited concern that there be greater bounds on this power. The following discussion provides an overview and background on the various features of the ESA that contribute to its stature and yet spark an ongoing debate over its implementation.


What is the ESA?

The Endangered Species Act (ESA) is a comprehensive attempt to protect identified species and to consider habitat protection as an integral part of that effort. It is administered primarily by the Fish and Wildlife Service (FWS), but also by the National Marine Fisheries Service (NMFS) for certain marine species. Under the ESA, species of plants and animals (both vertebrate and invertebrate) are listed as either “endangered” or “threatened” according to assessments of the risk of their extinction. Once a species is listed, powerful legal tools are available to aid the recovery of the species and to protect its habitat. As of June 28, 2009, a total of 1,893 species of animals and plants had been listed as either endangered or threatened; 1,320 of these occur in the United States and its territories and the remainder only in other countries. Of the U.S. species, 1,134 were covered by recovery plans. The authorization for funding under ESA expired on October 1, 1992, although Congress has appropriated funds in each succeeding fiscal year.

Why is the ESA controversial?

While the ESA plays an important role in protecting species, it can also become a surrogate in quarrels whose primary focus is the allocation of scarce or diminishing lands or resources. Indeed, a stated purpose of the ESA is to “provide a means whereby the ecosystems upon which endangered species and threatened species depend may be conserved.” There can be economic interests on the various sides of some vanishing species issues. Because other laws often lack the strict substantive provisions that Congress included in the ESA (see Major Provisions sections, below), the ESA often becomes a surrogate battleground in such disputes. Like the miners’ canaries, declining species are often symptoms of resource scarcities and altered ecosystems. Examples of such resource controversies include the Tellico Dam (hydropower development and construction jobs versus farmland protection and tribal graves, as well as the endangered snail darter); Northwest timber harvest (protection of logging jobs and communities versus commercial and sport fishing, recreation, and ecosystem protection, as well as salmon and spotted owls); and oil development on the energy-rich plain around the northern mountain states (coal bed methane development, grazing rights, ground water protection, traditional ranching, and a proposal for sage grouse listing in a complex and varying stew of interests). (Ultimately, a petition to list this species was judged not to be warranted.) And the worldwide debate over global warming has found its avatar in the polar bear.

In recent years, tensions over the ESA have increased as species have been added to the protected list, and as the greater demands of a growing economy and human population have affected species’ habitats. Both Congress and the Administration have sought to lessen these tensions by, among other things, tailoring application of the ESA for particular circumstances. The ESA’s critics contend that neither the ESA nor administrative efforts go far enough in accommodating needs other than species conservation, while the ESA’s defenders counter that it merely balances an inherent bias toward development in other governmental laws and policies.

Debate, pro and con, on the ESA splits largely along demographic lines. While most demographic groups support species conservation, that support is stronger among urban and suburban populations and less so in rural areas, and is stronger among those in the East and along the coasts and less so in central and mountain states. Sport hunters and anglers seem divided on the issue. Native Americans, as a group often dependent on natural resources (e.g. fish), are frequently involved in ESA issues, most commonly siding with survival of listed species. Groups opposing strong protections for listed species usually make claims that jobs will be lost if conservation measures are stringent, but those seeking strong protections often claim that jobs will be lost if they are not. It is also noteworthy that, while the debate often centers on jobs and biology, people on both sides claim ethical support for their positions, and some religious groups now participate in the debate. In addition, some industries (e.g., logging and land development) generally see the ESA as a serious problem, while others (e.g., some commercial fishing and many recreation interests) see it as generally supporting their interests.

Has ESA Been Effective?

The answer to this question depends very much on the choice of measurement. A major goal of the ESA is the recovery of species to the point at which the protection of the ESA is no longer necessary. If this is the standard, the ESA could be considered a failure, since only 21 species have been delisted due to recovery, to date. Nine species have become extinct since their listing, and have been delisted due to improved data. In the former case, some of the 9 species now believed extinct were originally listed to protect any last remaining few that might have been alive at the time of listing. It can be quite difficult to prove whether extraordinarily rare species are simply that, or in fact are already extinct. For example, a rare shorebird thought by many to be extinct was re-discovered in a remote area of Canada a few years ago; it might just as easily have quietly gone extinct without being rediscovered. Rare species are, by definition, hard to find.

Even so, since some scientific studies demonstrated that most species are listed only once they are very depleted (e.g., median population of 407 animals for endangered vertebrates according to one study), another measure of effectiveness might be the number of species that have stabilized or increased their populations, even if the species is not actually delisted. If this is the standard, the ESA could be considered a success, since a large number (41% of listed species according to one study) have improved or stabilized their population levels. Other species (e.g., red wolves and California condors) might not exist at all without ESA protection, and this too might be considered a measure of success, even though the species are still rare. One could also ask what species might have become extinct if there were no ESA. The authors are unaware of comprehensive studies regarding the likely status of rare species were there no ESA, but for species such as spotted owls, salmon, Florida panthers, and plants of very narrow ranges, it seems likely that their numbers would be (at best) far fewer if ESA did not exist.

Leading Causes of Extinction

Until recent decades, the focus of the extinction debate was on losses due to over-exploitation, generally through hunting, trapping, or fishing. The poster species of the debate were passenger pigeons, tigers, wolves, and other well-known animals. But during the 20th century, a shift of focus and probably of fact occurred. The vast majority of species, including those for which direct taking was probably an early factor in their decline, are generally also at risk due to habitat loss. Habitats reduced now to a small fraction of their former extent include tall-grass prairie, fresh and salt water wetlands, old growth forests of most types, free-flowing rivers, coral reefs, undisturbed sandy beaches, and others.

Another high-ranking factor in the demise of many species is the introduction of non-native species. The non-native (invasive) species can be disease vectors or parasites (e.g., avian malaria in Hawaii, or Asian long-horned beetles in North America), predators (brown tree snakes in Guam and Hawaii), or competitors (e.g., barred owls in the Pacific Northwest). The gradual homogenization of the world’s flora and fauna has led to a demise of many species.

Is Extinction Normal?

If extinction is normal, some argue that there is no need for the government to intervene to halt this natural process. But is it normal? Geological evidence shows that the vast majority of species that have ever lived on Earth are now extinct — an observation uncontested by paleontologists. However, many scientists are concerned that the current rate of extinction exceeds background extinction rates over time. (Over the billions of years of life on Earth, extinction rates have varied, with five periods of exceptionally high rates. The most famous periods are the mass extinctions at the end of the Age of Dinosaurs (Cretaceous Period), about 65 million years ago, and the even more massive die-offs at the end of the Permian Period, about 250 million years ago, when about 52% of the groups of marine species became extinct. Between each of these five events, extinctions continued at more moderate, background levels.) But calculating current rates of extinction, much less making comparisons with the geologic past, is extremely difficult. Current estimates of total species range from 3.5 million to 100 million, with 10-30 million being commonly accepted numbers. If scientists are unsure of how many species exist, it is naturally difficult to estimate how fast they are going extinct, and whether current extinction rates exceed background extinction rates. Consequently, scientists use very conservative assumptions to make these estimates. The resulting extinction rates (17,000 species per year being a typical estimate) still seem astonishingly large, in part because the public are generally unaware of the huge number of species in groups to which many people pay little or no attention (e.g., beetles, marine invertebrates, fish), and the large number of species estimated on Earth. How do these compare to background rates?

Widely diverse methods all suggest that current rates of extinction exceed background rates. Normal rates are thought to be from 1 to 10 species per every 10 million species per year. (That is, if there are 20 million species now, background levels would be about 2 to 20 species extinctions per year.) Common estimates of current extinction rates range from 100 to 10,000 times such background rates — roughly comparable to the five great episodes of extinction in the geologic past. Critics most frequently question these calculations by stressing uncertainties, rather than citing specific factual errors. This criticism is not surprising, since each step in these calculations contains uncertainties (e.g., estimating the number of existing species). Most biologists counter by noting that similar numbers are generated in studies of widely different groups by a variety of scientists using different methods. Robust results (i.e., similar results from the testing of a hypothesis in a variety of ways) are usually considered scientifically sound.

Once extinct, a species can never be revived. But faced with high rates of extinction, some might take comfort in a return to an equal number of species, even if those species are different. Evolution continues, even in the face of high extinction rates, so perhaps new species will evolve that are better adapted to new conditions. If so, how long would such a “recovery” take? Examining the geologic record after major extinction episodes, some scientists estimate that recovery to approximately equal numbers of (different) species took up to 25 million years for the most severe extinction events. Thus, if the current extinction rate and recovery rate are comparable to past rates, the return to species numbers of the pre-historic era would take several million years.

Major Provisions of Current Law: Domestic

The modern ESA was passed in 1973, but was preceded by simpler acts in 1966 and 1969. It has been amended on numerous occasions since then: 1976, 1977, 1978, 1979, 1980, 1982, and 1988. The following are brief summaries of the major domestic provisions of the ESA in the order they appear in the U.S. Code. Several major issues are discussed in more detail later in this report.

Endangered and Threatened Species

An endangered species is defined as “any species which is in danger of extinction throughout all or a significant portion of its range....” A threatened species is defined as “any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range.” The ESA does not rely on a numerical standard: such a standard would not reflect the wide variety of many species’ biology. (For example, a population of 10,000 butterflies, all confined to one mountaintop, would clearly be at greater risk than 10,000 butterflies scattered over thousands of square miles.) The protection of the ESA extends to all species and subspecies of animals (not just birds and mammals), although for vertebrates, further protection can be given for distinct population segments within a species, and not just the species as a whole. More limited protection is available for plant species under the ESA. There is currently no protection afforded under the ESA for organisms (e.g., Eubacteria, Archaea, viruses) considered neither animal nor plant.


The term “take” under the ESA means “to harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct.” (Harassment and harm are further defined in regulation at 50 C.F.R. §17.3.) Taking is prohibited under 16 U.S.C. §1538. There has been controversy over the extent to which the prohibition on taking may include habitat modification. A 1995 Supreme Court decision ([[Sweet Home Decision| Sweet Home]) held that the inclusion of significant habitat modification was a reasonable interpretation of the term “harm” in the law.

Fish and Wildlife Service and National Marine Fisheries Service

The Secretary of the Interior manages and administers most listed species through FWS. Marine species, including some marine mammals, and anadromous fish are the responsibility of the Secretary of Commerce, acting through and NMFS. The law assigns the major role to the Secretary of the Interior (all references to “Secretary” below are to the Secretary of the Interior unless otherwise stated) and provides in detail for the relationship of the two Secretaries and their respective powers.


Species may be listed on the initiative of the appropriate Secretary or by petition from an individual, group, or state agency. The Secretary must decide whether to list the species based only on the best available scientific and commercial information, after an extensive series of procedural steps to ensure public participation and the collection of relevant information. At this point, the Secretary may not consider the economic effects that listing may have on the area where the species occurs. This is the only place in the ESA where economic considerations are expressly forbidden; such considerations may enter in a later stage. Economic factors cannot be taken into account at this stage, because Congress directed that listing be fundamentally a scientific question: is the continued existence of the species threatened or endangered? Through the 1982 amendments particularly, Congress clearly intended to separate this scientific question from subsequent decisions on appropriate protection. This is evident upon comparing 16 U.S.C. §1533(b) with §1533(f) in this regard.

Candidate Species

In the interval between a proposal and a listing decision, the Secretary must monitor the status of these “candidate” species and, if any emergency poses a significant risk to the well-being of the species, promptly list them. Some steps in the normal listing process may be skipped for emergency listings. Federal agencies must confer with the appropriate Secretary on actions likely to jeopardize the continued existence of candidate species, but agencies need not limit commitments of resources. As of July 27, 2009, there were 248 candidate species.

Delisting and Downlisting

The processes for delisting or downlisting a species from the Lists of Endangered and Threatened Wildlife and Plants are the same as the processes for listing. Delisting is removing a species from the lists. Downlisting is reclassifying a species from endangered to threatened, and uplisting is the reverse. The Secretary of the Interior may initiate a change in the status of listed species. Alternatively, after receiving a substantive petition for any change in listing status, the Secretary is to review the species’ status. The determination to delist, downlist, or uplist a species must be made “solely on the basis of the best scientific and commercial data available” and “without reference to possible economic or other impacts.” FWS regulations also state that, at least once every five years, the Director review each listed species to determine whether it should be removed from the list, changed from endangered to threatened, or changed from threatened to endangered.

Critical Habitat

When a species is listed, the Secretary must also designate critical habitat (either where the species is found or, if it is not found there, where there are features essential to its conservation). If the publication of this information is not “prudent” because it would harm the species (e.g., by encouraging vandals or collectors), the Secretary may choose not to designate critical habitat. The Secretary may also postpone designation for as long as one year if the information is not determinable. As of August 10, 2009, critical habitat had been designated for 544 listed species. Any area, whether or not federally owned, may be designated as critical habitat, but private land is only affected by critical habitat designation if some federal action (e.g., license, loan, permit) is also involved. Federal agencies must avoid “destruction or adverse modification” of critical habitat, either through their direct action or activities that they approve or fund.

Recovery Plans

The appropriate Secretary must develop recovery plans for the conservation and survival of listed species. Recovery plans to date tend to cover birds and mammals, but a 1988 ESA amendment prohibits the Secretary from favoring particular taxonomic groups. The ESA and its regulations provide little detail on the requirements for recovery plans, nor are these plans binding on federal agencies or others, and the essentially hortatory nature of these plans has been widely criticized. As of August 10, 2009, recovery plans had been completed for 1,134 U.S. species.

Land Acquisition

Land may be acquired to conserve (recover) endangered and threatened species, and money from the Land and Water Conservation Fund may be appropriated for this acquisition. In fiscal year (FY) 2005, a total of 1,655 acres were acquired by FWS for the National Wildlife Refuge System under ESA authority.

Cooperation with States

The appropriate Secretary must cooperate with the states in conserving protected species and must enter into cooperative agreements to assist states in their endangered species programs, if the programs meet certain specified standards. If there is a cooperative agreement, the states may receive federal funds to implement the program, but the states must normally provide a minimum 25% matching amount. The 1988 ESA amendments created a fund to provide for the state grants. While the authorized size of the fund is determined according to a formula, money from the fund still requires annual appropriation. For FY2007, a total of almost $81.0 million was provided to states and territories for cooperative activities, including land acquisition and planning assistance.


Federal agencies must ensure that their actions are “not likely to jeopardize the continued existence” of any endangered or threatened species, nor to adversely modify critical habitat. If federal actions or actions of non-federal parties that require a federal approval, permit, or funding might affect a listed species, the federal action agencies must complete a biological assessment. To be sure of the effects of their actions, the action agency must consult with the appropriate Secretary. This is referred to as a § 7 consultation. “Action” includes any activity authorized, funded, or carried out by a federal agency, including permits and licenses. However, a 2007 Supreme Court decision held that the consultation process is required only for those federal actions that involve agency discretion. Where a federal action is dictated by statute, such as where an agency must act if certain listed conditions are
met, a § 7 consultation is not required.

If the appropriate Secretary finds that an action would not jeopardize a species or adversely modify critical habitat, the Secretary issues a Biological Opinion (“BiOp”) to that effect, and the agency is provided with a written statement under 16 U.S.C. § 1536(b)(4), specifying the terms and conditions under which the federal action may proceed in order to avoid jeopardy or adverse modification of critical habitat. The Secretary must suggest any reasonable and prudent alternatives that would be required to avoid harm to the species. The great majority of consultations result in “no jeopardy” opinions, and nearly all of the rest find that the project has reasonable and prudent alternatives which will permit it to go forward. Actions that would result in jeopardy and have no reasonable and prudent alternatives are exceptionally rare. If no reasonable and prudent alternatives to the proposed action can be devised to avoid the jeopardy or adverse modification, the agency has three choices: (1) choose not to proceed with the action; (2) proceed with the action at the risk of penalties; or (3) apply for a formal exemption for the action.38 Pending completion of the consultation process, agencies may not make irretrievable commitments of resources that would foreclose any of these alternatives.


A federal agency, an applicant or permittee, or the governor of a state in which the action in question would occur may apply for an exemption that allows the action to go forward without penalties. Exemptions are only available for actions (e.g., water withdrawal), not for species (e.g., Delta smelt). A high-level Endangered Species Committee of six specified federal officials and a representative of each affected state (commonly called the “God Squad”) decides whether to allow the action to proceed despite future harm to a species; at least five votes are required to pass an exemption. The law includes extensive rules and deadlines to be followed in applying for such an exemption and some stringent rules for the Committee in deciding whether to grant an exemption. The Committee must grant an exemption if the Secretary of Defense determines that an exemption is necessary for national security. In addition and under specified circumstances, the President may determine whether to exempt a project for the repair or replacement of facilities in declared disaster areas. See a separate discussion of the complex exemption process and its history, below, in the Appendix.

Permits for Non-Federal Actions

For actions that might take a listed species, but without any federal nexus such as a loan or permit, the Secretary may issue permits to allow “incidental take” of species for otherwise lawful actions. The applicant for an incidental take permit must submit a habitat conservation plan (HCP) that shows the likely impact, the steps to minimize and mitigate the impact, the funding for the mitigation, the alternatives that were considered and rejected, and any other measures that the Secretary may require. Secretary Babbitt greatly expanded use of this section during the Clinton Administration, and an agency handbook provides for streamlined procedures for activities with minimal impacts.

Other Provisions

Other provisions specify certain exemptions for raptors; regulate subsistence activities by Alaskan Natives; prohibit interstate transport and sale of listed species and parts; control trade in parts or products of an endangered species that were owned before the law went into effect; and specify rules for establishing experimental populations. (Provisions of the ESA referring to international activities are discussed below.)

Prohibitions and Penalties

The ESA prohibits certain actions, specifies criminal and civil penalties, and provides for citizens’ suits to enforce certain aspects of the ESA. The citizen suit provisions have been a driving force in the ESA’s history, and often have been used to force reluctant agencies to provide for species conservation that might otherwise have been neglected.

Major Provisions of Current Law: International

The ESA implements the Convention on International Trade in Endangered Species of Wild Fauna and Flora (“CITES”, signed by the United States on March 3, 1973); and the Convention on Nature Protection and Wildlife Preservation in the Western Hemisphere (the “Western Hemisphere Convention” signed by the United States on October 12, 1940). CITES parallels the ESA by dividing its listed species into groups, according to the estimated risk of extinction, but uses three major categories, rather than two. In contrast to the ESA, CITES focuses exclusively on trade, and does not consider or attempt to control habitat loss. The following are the major international provisions of the ESA.

Financial Assistance

The Secretary may use foreign currencies (available under 7 U.S.C. §1691, the Food for Peace program) to provide financial assistance to other countries for conserving endangered species. (As a practical matter, little money is currently available under this provision.) The ESA also authorizes appropriations for this purpose.

Scientific Authority/CITES

The ESA designates the Interior Secretary as the Endangered Species Scientific Authority (ESSA) under CITES. As the ESSA, the Secretary must determine that the United States’ international trade of living or dead organisms, or their products, will not harm the species in question. The Secretary has authority to enforce these determinations. The Secretary is required to base export determinations upon “the best available biological information,” although population estimates are not required. Certain other responsibilities are also spelled out in CITES.

Management Authority/CITES

The Interior Secretary is also named as the Management Authority for the United States under CITES. The Management Authority must assure that specimens are exported legally, that imported specimens left the country of origin legally, and that live specimens are shipped under suitable conditions. Certain other responsibilities are also spelled out in CITES.


The ESA makes violations of CITES violations of U.S. law if committed within the jurisdiction of the United States.


The ESA requires importers and exporters of controlled products to use certain ports and provides for exemptions for scientific purposes and for programs intended to assist the recovery of listed species. There are also certain exemptions for Alaska Natives and for products owned before December 28, 1973, including scrimshaw (carved ivory).

Particular Species

The 1988 ESA amendments (Title II of P.L. 100-478; 16 U.S.C. §§4201 et seq.) created a major program for the conservation of African elephants. In 1994Congress enacted a separate program for rhinoceros and tigers (P.L. 103-391; 16 U.S.C. §§ 5301 et seq.). In 1997, a program for Asian elephants was established (P.L. 105-96; 16 U.S.C. §§ 4261 et seq.). In 2000, a program for great apes was added (P.L. 106-411; 16 U.S.C. §§ 6301 et seq.). In 2004, a program for marine turtles was added (P.L. 108-266; 16 U.S.C. §§ 6601 et seq.). While none of these programs is formally part of the ESA authorization per se, they provide funds for species which are protected under the ESA.

Analysis of Domestic Law Provisions

Because the listing of species, the designation of critical habitat, and the consultation and exemption processes are such important and controversial aspects of the ESA, each of these components is discussed in greater detail in this portion of the report.


Bases for Listings. As discussed above, the listing of a species under the ESA results in greater protection for the species, limitations on activities that might affect that species, and penalties for “taking” individuals of a listed species.

A species may be designated as either endangered or threatened, depending on the severity of its decline and threats to its continued survival. Under § 3 of the ESA, an endangered species is a species that is “in danger of extinction throughout all or a significant portion of its range.” A threatened species is defined as a species “likely to become endangered within the foreseeable future throughout all or a significant portion of its range.” Because the ESA defines species as a species, a subspecies, or, — for vertebrates only — a “distinct population segment,” there is some flexibility as to how to provide different levels of protection to less than a whole species.

In the last several years, the Department of the Interior (DOI) has interpreted the definition of endangered species to find that only a species that is in danger of extinction throughout all of its range is truly endangered. Under this interpretation, a species that was at risk of extinction in a significant portion of its range would not be considered endangered. Just about every court that considered the issue found DOI’s interpretation violated the ESA, including one federal court of appeals. And in 2007, DOI changed its interpretation.55 Under the new interpretation issued by the Solicitor of DOI, FWS must also consider whether a species is at risk of extinction throughout a significant portion of its range, allowing the agency discretion to define significant. The interpretation also states that the range of a species is the area in which a species currently exists, not the historical range where the species once existed.

The determination of whether a species should be listed as endangered or threatened must be based on several scientific factors related to a species and threats to its continuance. The ESA expressly states that listing determinations are to be made “solely on the basis of the best scientific and commercial data available.” The word “solely” was added in the 1982 amendments to the ESA58 to clarify that the determination of endangered or threatened status was intended to be made without reference to its potential economic impacts. Observers have compared the decision of whether to list a species to diagnosing whether a patient has cancer: the diagnosis should be a strictly scientific decision, but other factors can be considered later in deciding how to treat the cancer. In discussing the addition of the word “solely,” a committee report stated:

... The principal purpose of the amendments to Section 4 is to ensure that decisions pertaining to the listing and delisting of species are based solely upon biological criteria and to prevent non-biological considerations from affecting such decisions. To accomplish this and other purposes, Section 4(a) is amended in several instances.

Section 4(b) of the Act is amended in several instances by Section 1(a)(2) of H.R. 6133. First, the legislation requires that the Secretary base his determinations regarding the listing or delisting of species “solely” on the basis of the best scientific and commercial data available to him. The addition of the word “solely” is intended to remove from the process of the listing or delisting of species any factor not related to the biological status of the species. The Committee strongly believes that economic considerations have no relevance to determinations regarding the status of species and intends that the economic analysis requirements of Executive Order 12291, and such statutes as the Regulatory Flexibility Act and the Paperwork Reduction Act not apply. The committee notes, and specifically rejects, the characterization of this language by the Department of the Interior as maintaining the status quo and continuing to allow the Secretary to apply Executive Order 12291 and other statutes in evaluating alternatives to listing. The only alternatives involved in the listing of species are whether the species should be listed as endangered or threatened or not listed at all. Applying economic criteria to the analysis of these alternatives and to any phase of the species listing process is applying economics to the determinations made under Section 4 of the Act and is specifically rejected by the inclusion of the word “solely” in this legislation.

Section 4(b) of the Act, as amended, provides that listings shall be based solely on the basis of the best “scientific and commercial data” available. The Committee did not change this information standard because of its interpretation of the word “commercial” to allow the use of trade data. Retention of the word “commercial” is not intended, in any way, to authorize the use of economic considerations in the process of listing a species.

The conference report confirms that it was the intent of both chambers that economic factors not play a role in the designation and listing of species for protection:

Section 2 of the Conference substitute amends section 4 of the Act in several ways. The principal purpose of these amendments is to ensure that decisions in every phase of the process pertaining to the listing or delisting of species are based solely upon biological criteria and to prevent non-biological considerations from affecting such decisions.

The Committee of Conference (hereinafter the Committee) adopted the House language which requires the Secretary to base determinations regarding the listing or delisting of species “solely” on the basis of the best scientific and commercial date available to him. As noted in the House Report, economic considerations have no relevance to determinations regarding the status of species and the economic analysis requirements of Executive Order 12291, and such statutes as the Regulatory Flexibility Act and the Paperwork Reduction Act, will not apply to any phase of the listing process. The standards in the Act relating to the designation of critical habitat remain unchanged. The requirement that the Secretary consider for listing those species that states or foreign nations have designated or identified as in need of protection also remains unchanged.

The Committee adopted, with modifications, the Senate amendments which combined and rewrote section 4(b) and (f) of the Act to streamline the listing process by reducing the time periods for rulemaking, consolidating public meeting and hearing requirements and establishing virtually identical procedures for the listing and delisting of species and for the designation of critical habitat.

In summary, the ESA makes clear that whether a species is endangered or threatened is a scientific question in which economic factors must not play a part. Once this determination is made, economics then may be considered in analyzing and taking other actions such as designating critical habitat or developing recovery plans. Nothing in the ESA prevents choosing conservation methods that will lower costs to society, industry, or landowners, as long as the chosen methods still achieve conservation goals.

Pre-Listing Activities. The question may arise as to what the responsibilities of the federal government are toward a species that is proposed for listing but has not yet been listed. This question could be important because there may be a significant time between the proposal for listing and the actual listing, during which time a federal agency could be faced with decisions on contracts and management actions of various types. Under current law, an agency must “confer” with the appropriate Secretary on any agency action that is likely to jeopardize the continued existence of any species proposed to be listed or to destroy or adversely modify critical habitat proposed to be designated for such species. The implementing regulations state that the conference is designed to assist the federal agency and an applicant in identifying and resolving potential conflicts at an early stage in the planning process.

The conference process that applies to species proposed for listing is distinct from the consultation process that applies to listed species. The conference is intended to be less formal, and to permit FWS or NMFS to advise an agency on ways to minimize or avoid adverse effects. A federal agency has to follow more formal procedures and provide more complete documentation once a species is listed. The agency may choose to follow the more complete and formal process even at the proposed listing stage to avoid duplication of effort later.

The ESA states that the conference stage does not require a limitation on the irreversible or irretrievable commitment of resources by agency action which would foreclose reasonable and prudent alternative measures. Once a species is listed, an agency will have definite responsibilities, and an agency might consider it prudent at the proposed listing stage both to avoid harm to a precarious species and to avoid possible liability for compensation arising from agency actions creating private rights which later cannot be exercised. An agency might, for example, choose to avoid holding timber sales in an area containing a proposed species. The relevant Secretary must monitor candidate species and prevent a significant risk to the well being of any such species.

Special Protection for Threatened Species. Under § 4(d) of the ESA, the Secretary may promulgate special regulations to address the conservation of species listed as threatened. Protections and recovery measures for a particular threatened species can be carefully tailored to particular situations, as was done, for example, with respect to the threatened northern spotted owl. A federal regulation also clarifies that a threatened species for which a special rule has not been promulgated enjoys the same protections as endangered species.

Designation of Critical Habitat

Critical habitat designation has been controversial, given FWS’s stated position (see below), the importance that the environmental community attaches to critical habitat (especially in some specific cases), and the distress its designation causes among many landowners.

Concurrently with determining a species to be endangered or threatened, the Secretary “to the maximum extent prudent and determinable” is to designate the critical habitat of the species. The reference to the designation of critical habitat being “prudent” reflects the need to consider whether designating habitat would harm the species, for example, by identifying areas that could be damaged by specimen collecting. If the facts relevant to the designation of critical habitat are not yet “determinable,” the Secretary may postpone habitat designation for an additional year. Eventually, habitat is to be designated to the maximum extent it is prudent to do so.

If the Secretary designates critical habitat, the Secretary must do so

on the basis of the best scientific data available and after taking into consideration the economic impact, and any other relevant impact, of specifying any particular area as critical habitat. The Secretary may exclude any area from critical habitat if he determines that the benefits of such exclusion outweigh the benefits of specifying such area as part of the critical habitat, unless he determines, based on the best scientific and commercial data available, that the failure to designate such area as critical habitat will result in the extinction of the species concerned.

Therefore, although economic factors are not to be considered in the listing of a species as endangered or threatened, economic factors are considered in the designation of critical habitat, and some habitat areas may be excluded from designation based on such concerns, unless the failure to designate habitat would result in the extinction of the species.

Although avoiding adverse modification of critical habitat is an express obligation only for federal agencies and actions, it is frequently misunderstood by the public as the major restriction on a private landowner’s authority to manage land. The bulk of any restrictions on use of private land come primarily from the ESA’s prohibition on taking of listed species. Only occasionally — when some federal nexus is present — are they due to any additional strictures resulting from designated critical habitat.

Both the Clinton and George W. Bush Administrations have supported restrictions on their own ability to designate critical habitat under the ESA (e.g., proposed restrictions under the appropriations process). In an announcement on October 22, 1999, FWS placed designation of critical habitat at the lowest priority in its listing budget, and stated that it could not comply with all of the demands of the ESA under current budget constraints. Conservation groups saw a contradiction between that claim, and the agency’s repeated failure to request increased funds for listing, together with requests that Congress place a special cap on funding for designation of critical habitat.

FWS has designated critical habitat for 534 of the 1,320 listed domestic species (as of August 10, 2009). The agency has been sued frequently for its failure to designate critical habitat and consistently loses such suits. In the agency’s view, critical habitat offers little protection for a species beyond that already available under the listing process, and thus the expense of designation, combined with its perception of a small margin of additional conservation benefit, make critical habitat requirements a poor use of scarce budgetary resources, especially if the public views critical habitat as the major regulatory impact of the ESA, rather than as a supplement to the ESA’s prohibition on “taking” a listed species.

According to FWS, critical habitat designation shows its greatest conservation benefit when it includes areas not currently occupied by the species; these areas may be important as connecting corridors between populations or as areas in which new populations may be re-introduced. FWS proposed to “develop policy or guidance and/or revise regulations, if necessary, to clarify the role of habitat in endangered species conservation.” The notice reflected the agency’s longstanding disaffection for this provision of the law and its view that its conservation benefit is low compared to its cost. However, while workshops were held on the topic, ultimately, no action was taken on the proposal.

These agency assertions and conclusions rest on an agency regulation in 2000 that fails to consider the role of critical habitat in the recovery of species, rather than its mere survival. In 2001, a federal court of appeals rejected that regulatory interpretation. In 2004, a second federal court of appeals found the regulation contradicted the statute. If the agency interpretation is changed to more closely reflect the statute, the role of critical habitat arguably would be more meaningful in practice.

Post-Listing Activities/Consultation

Under §7 of the ESA, federal agencies are required to consult with the Secretary about proposed actions that might affect a listed species; to use their authorities in furtherance of the ESA; and to insure that any action authorized, funded, or carried out by the agency is not likely to jeopardize the continued existence of any endangered or threatened species, or to destroy or adversely modify critical habitat unless the agency has been granted an exemption under the ESA. Consultation is usually begun at the request of the action agency, but may be initiated at the request of a FWS Regional Director or NMFS’s Assistant Administrator for Fisheries.

Science plays an important role in the consultation process because the Secretary is to use the “best scientific and commercial data available” to ascertain if a listed species might be present in the area of a proposed agency action. If so, the action agency is to prepare a “biological assessment” to explore whether a proposed action might jeopardize a listed species or its critical habitat. This assessment also is to be based on “the best scientific and commercial data available.” Consultation must also be initiated in connection with private lands if an applicant for (or recipient of) federal funding, permit, or license has reason to believe that a listed species may be present in the area affected by a project and implementation of the action will likely affect a listed species.

The relevant Secretary generally is to complete consultation within 90 days for a wholly federal action, unless the Secretary and the federal agency mutually agree to a longer period (up to 150 days) and reasons are given for the delay. A consultation involving a non-federal party is to be completed within the time agreed to by the Secretary, the federal agency involved, and the applicant concerned.

Thereafter, FWS or NMFS will prepare a written statement, known as the biological opinion, analyzing whether the proposed agency action is likely to jeopardize the continued existence of a listed species or destroy or adversely modify critical habitat. The ESA does not expressly state that the biological opinion is to be based on the “best scientific and commercial data available,” but this arguably is implied, and is expressly required under the implementing regulations, which require that the consulting agency provide “the best scientific and commercial data available or which can be obtained during the consultation.” Such information is to be the basis of the biological opinion, and the biological opinion is to include a summary of the information on which the opinion is based.

The biological opinion may conclude that the agency action is not likely to jeopardize the species, or that it can be modified to avoid jeopardy. If so, FWS or NMFS may issue a permit that excuses the taking of listed species incidental to the otherwise lawful activities that are to take place. If the biological opinion concludes that the proposed action is likely to jeopardize, FWS or NMFS must suggest reasonable and prudent alternatives to avoid jeopardy and mitigate the impacts of the action. If this is not possible, then the agency proposing the action must forego the action, risk incurring penalties under the ESA, or obtain a formal exemption from the penalties of the ESA as set out below.

Exemptions: A History

The Endangered Species Committee. If the jeopardy that is expected to result from a proposed agency action cannot be avoided and the agency proposing the action nonetheless wishes to go ahead with the action, the agency (or the affected governor(s) or license applicant(s)) may apply for an exemption to allow the action to go forward. The exemption process is an important way in which economic factors may be taken into account under the ESA. Because the exemption process involves convening a cabinet-level committee, there have only been six instances to date in which the exemption process was initiated. Of these six, one was granted, one was partially granted, one was denied, and three were dropped (see Appendix).

As originally enacted, the ESA contained an absolute prohibition against activities detrimental to listed species. When the prospective impoundment of water behind the nearly completed Tellico dam threatened to eradicate the only known population of the snail darter (a fish related to perch), the Supreme Court concluded that the then-current “plain language” of the ESA mandated that the gates of the dam not be closed:

Concededly, this view of the Act will produce results requiring the sacrifice of the anticipated benefits of the project and of many millions of dollars in public funds. But examination of the language, history, and structure of the legislation under review here indicates beyond doubt that Congress intended endangered species to be afforded the highest of priorities. (Tennessee Valley Authority v. Hill, 437 U.S. 153, 174 (1978))

After this Supreme Court decision, the ESA was amended by P.L. 95-632 to include a process by which economic impacts could be reviewed and projects exempted from the restrictions that otherwise would apply. As originally enacted, the exemption process involved recommendations by the Secretary of the Interior, processing by a review board, and then an application to the Endangered Species Committee (ESC). In 1982, P.L. 97-304 changed this process to eliminate the review board. Currently, the reviewing Committee is composed of the Secretary of Agriculture, the Secretary of the Army, the Chair of the Council of Economic Advisors, the Administrator of the Environmental Protection Agency, the Secretary of the Interior (who chairs the ESC), the Administrator of the National Oceanic and Atmospheric Administration, and one individual from each affected state. By regulation, Committee members from affected states collectively have one vote.

Eligible Applicants. A federal agency, the governor of a state in which an agency action will occur, or a permit or license applicant may apply to the Secretary for an exemption for an agency action. How an agency action is structured — whether, for example, it is a separate action or a region-wide program — could be relevant to the various findings required under the exemption procedures. The term “permit or license applicant” is defined in the ESA as a person whose application to a federal agency for a permit or license has been denied primarily because of ESA prohibitions applicable to the agency action. The regulations do not elaborate on who is included within this term.

An exemption application from a federal agency must describe the consultation process carried out between the head of the federal agency and the Secretary, and include a statement explaining why the action cannot be altered or modified to conform with the requirements of the statute. All applications must be submitted to the Secretary not later than 90 days after completion of the consultation process, or within 90 days of final agency action if the application involves a federal permit or license. An application must set out the reasons the applicant considers an exemption warranted. The Secretary then publishes a notice of receipt of the application in the Federal Register and notifies the governor of each affected state (as determined by the Secretary) so that state members can be appointed to the ESC. The Secretary (acting alone) may deny the application, if the preliminary steps have not been completed.

To be eligible for an exemption, the federal agency concerned and the exemption applicant must have carried out the consultation processes required under §7 of the ESA in good faith. The agency also must have made a reasonable and responsible effort to develop and fairly consider modifications or reasonable and prudent alternatives to the proposed action that would not jeopardize the continued existence of any endangered or threatened species or destroy or adversely modify critical habitat of a species. In addition, the agency must have conducted required biological assessments; and, to the extent determinable within the time provided, refrained from making any irreversible or irretrievable commitment of resources that would foreclose the formulation or implementation of reasonable and prudent alternatives that would avoid jeopardizing the species and/or adversely modifying its habitat. These qualifying requirements were put in place to insure that the exemption process is meaningful and that consideration of the issues would not be preempted by actions already taken. Additional requirements for an application are contained in the relevant regulations.

It is important to note that the exemption process begins only after a species is listed, consultation has occurred, a finding has been made that the agency action is likely to jeopardize a species, and it is determined that there are no reasonable and prudent alternatives to the agency action.

Secretarial Review. The Secretary is to determine whether an application is qualified within 20 days or a time mutually agreeable to the applicant and the Secretary. Within 140 days of the time the Secretary determines that the applicant is qualified, the Secretary, in consultation with the other members of the ESC, must hold a formal hearing on the application and prepare a report. The purpose of the formal hearing is to collect evidence both favoring and opposing the exemption. The Secretary’s report reviews whether the applicant has made any irreversible or irretrievable commitment of resources; discusses the availability of reasonable and prudent alternatives and the benefits of each; provides a summary of the evidence concerning whether the action is in the public interest and is nationally or regionally significant, and, if so, states why; and outlines appropriate and reasonable mitigation and enhancement measures which should be considered by the ESC.

Committee Determination. Within 30 days after receiving the report of the Secretary, the ESC is to grant or deny an exemption. The ESC shall grant an exemption for the project or activity if, based on the evidence, the ESC determines that

(i) there are no reasonable and prudent alternatives to the agency action;
(ii) the benefits of such action clearly outweigh the benefits of alternative courses of action consistent with conserving the species or its critical habitat, and such action is in the public interest;
(iii) the action is of regional or national significance; and
(iv) neither the federal agency concerned nor the exemption applicant made any irreversible or irretrievable commitment of resources prohibited by subsection (d) of this section [commitments as described above that jeopardize species or critical habitat].

Mitigation. If the ESC grants an exemption, it also must establish reasonable mitigation and enhancement measures that are “necessary and appropriate to minimize the adverse effects” of an approved action on the species or critical habitat. The exemption applicant (whether federal agency, governor, or permit or license applicant) is responsible for carrying out and paying for mitigation.

The costs of mitigation and enhancement measures specified in an approved exemption must be included in the overall costs of continuing the proposed action, and the applicant must report annually to the Council on Environmental Quality on compliance with mitigation and enhancement measures.

Special Circumstances. The ESA specifies certain particular instances when special provisions will apply.

  1. Review by the Secretary of State. The ESC cannot grant an exemption for an agency action if the Secretary of State, after a hearing and a review of the proposed agency action, certifies in writing that carrying out the action for which an exemption was sought would violate a treaty or other international obligation of the United States. This provision could enter in if a particular species listed under the ESA were also protected under treaties, such as the Migratory Bird Treaties to which the United States is a party. The Secretary of State is to make this determination within 60 days “of any application made under this section,” a time limit which may be unrealistic given the longer length of time the Secretary of the Interior has to prepare the report that will fully describe the agency action to be reviewed by the Secretary of State.

  2. National Security. The Committee is required to grant an exemption if the Secretary of Defense finds that an exemption is necessary for reasons of national security. We know of no instance on the public record in which this provision has been used.

  3. Domestic Disasters. The President may grant exemptions in certain cases involving facilities in declared disaster areas. This provision appears to be written in contemplation of domestic disasters, such as hurricanes. The ESA does not have a general provision that allows the granting of an exemption in other emergency conditions.

Duration and Effect of Exemption. An exemption is permanent unless the Secretary finds that the exemption would result in the extinction of a species that was not the subject of consultation or was not identified in a biological assessment and the ESC determines that the exemption should not be permanent.

The ESA expressly states that the penalties that normally apply to the taking of an endangered or threatened species do not apply to takings resulting from actions that are exempted.

Appendix: Exemption Applications

In three instances, an Endangered Species Committee (ESC) reached a decision on an application for an exemption:

Grayrocks Dam
The Platte River is a major stopover site on the migration path of whooping cranes, listed under the ESA as an endangered species. FWS determined that the construction of the Grayrocks Dam and Reservoir in Wyoming, along with existing projects in the Platte River Basin, would jeopardize the downstream habitat of whooping cranes. The Endangered Species Committee voted (7-0) to grant an exemption for Grayrocks Dam and Reservoir on January 23, 1979, conditioned on specified mitigation measures that included maintenance and enhancement of critical whooping crane habitat on the Platte River. A previous enactment by Congress would have exempted the project, if the ESC had not reached a decision within a certain time.

Tellico Dam
The Tellico Dam on the Little Tennessee River was to serve multiple purposes, but was vigorously opposed by several sectors. After the snail darter (a fish) was listed as endangered, litigation was filed to stop the construction of the dam, resulting in the significant case TVA v. Hill, which contains important language on the ESA and on possible ratification of projects through appropriations measures. The Tellico situation was also subject to P.L. 95-632 that provided for an expedited ESC process and an automatic exemption, if the ESC did not reach a decision within a specified time. The ESC denied an exemption for Tellico (on a 7-0 vote), but Congress enacted an exemption in P.L. 96-69, and the dam was completed. Subsequently, additional snail darters were found in a few other locations, and the snail darter was reclassified as threatened.

Bureau of Land Management Timber Sales
The Bureau of Land Management, an agency in the Department of the Interior, sought an exemption for 44 Oregon timber sales in the habitat of the northern spotted owl. In 1992, the ESC voted (5-2) to grant an exemption for 13 of the sales. Controversy over the sales and the processes within the Department continued, and the application was subsequently withdrawn.

In three other instances, there were applications for exemptions, but no ESC decisions:

Pittston Company Refinery
The Pittston Company applied for an exemption to build a refinery in Eastport, Maine. Following jeopardy opinions based on probable effects on threatened bald eagles and endangered [[Right Whale| right] and humpback whales, the company applied for an exemption, but further action on this application appears to have been discontinued in 1982.

Consolidated Grain and Barge Company Docking Area
This company sought to build a docking area for barges at Mound City, Illinois, on the Ohio River, an area that was habitat for an endangered mussel. Following a jeopardy opinion, and a denial of permits by the Army Corps of Engineers, the company applied for an exemption, but withdrew the application in 1986.

Suwanee River Authority
The consulting engineer of the Suwanee River Authority applied for an exemption for a project to dredge Alligator Pass in Suwanee Sound, Florida, part of the habitat for the endangered manatee. The project had been denied a permit by the Army Corps of Engineers. The engineer apparently lacked the authority to apply on behalf of the Authority, which in 1986 refused to ratify his actions and withdrew the application. Although the engineer attempted to continue the application, the withdrawal was effective.

Further Reading

See also environmental laws of United States Fish and Wildlife Service

Disclaimer: This article is taken wholly from, or contains information that was originally published by, the Congressional Research Service. Topic editors and authors for the Encyclopedia of Earth may have edited its content or added new information. The use of information from the Congressional Research Service should not be construed as support for or endorsement by that organization for any new information added by EoE personnel, or for any editing of the original content.

'''Note:'''The first version of this article was drawn from material prepared for the Congressional Research Service by M. Lynne Corn, Eugene H. Buck and Pamela Baldwin



(2009). Endangered Species Act, United States. Retrieved from http://www.eoearth.org/view/article/51cbedab7896bb431f69322e


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