The Endangered Species Act: Overview and Implementation

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The Endangered Species Act: Overview and

Implementation

Updated March 4, 2021

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R46677

SUMMARY

The Endangered Species Act: Overview and

Implementation

The Endangered Species Act of 1973 (ESA; P.L. 93-205, 87 Stat. 884, 16 U.S.C. §§1531-1544)

aims to conserve species listed as endangered or threatened under the act. Under the ESA, it is

the policy of Congress that all federal agencies shall seek to conserve threatened and endangered

species, use their authorities in furtherance of the ESA, and cooperate with state and local

agencies to resolve water resource issues in concert with conserving endangered species. The

ESA is administered by the U.S. Fish and Wildlife Service (FWS) and the National M arine

Fisheries Service (NMFS). Under the ESA, domestic and foreign species of animals (both

vertebrate and invertebrate) and plants can be listed as either endangered or threatened, according

to an assessment of the risk of their extinction. Once a species is listed, the act provides tools to

aid the species’ conservation and recovery and to protect its habitat.

R46677

March 4, 2021

Pervaze A. Sheikh

Specialist in Natural

Resources Policy

Erin H. Ward

Legislative Attorney

R. Eliot Crafton

Analyst in Natural

Resources Policy

The ESA and its predecessors have been in place since 1966. Since enactment, these acts have

led to the listing of over 2,400 species as threatened or endangered. As of October 2020, 2,363

species were listed, the majority of which (71%) were listed in the United States; the remaining

29% were foreign species. Of all listed species in October 2020, 79% were endangered and 21% were threatened. As of

October 2020, 91 species had been delisted under the ESA since it was enacted in 1973, which is approximately 3.7% of the

total number of species ever listed under the act.

Many Members of Congress are interested in how the ESA is implemented , because states—as well as American Samoa,

Guam, the Northern Mariana Islands, Puerto Rico, the Virgin Islands, outlying Islands in the Pacific and the Caribbean, and

Washington, DC—have species that are, or may be in the future, listed under the act. Congress also is interested in broader

issues surrounding the ESA and oversight of its implementation, primarily because some stakeholders perceive the ESA as, at

times, pitting economic development against the conservation of listed species.

This report discusses selected provisions of the ESA and selected federal regulations that implement the ESA. It discusses

several major provisions of the act, generally in the order they appear in the U.S. Code. These sections include Section 4, on

listing species under the ESA; Section 6, on cooperating with states in recovering listed species; Section 7, on interagency

cooperation and consultation; Section 9, on prohibitions under the ESA; Section 10, on exceptions to prohibitions; Section

11, on penalties and enforcement under the ESA; and Section 8, on the implementation of the Convention on International

Trade in Endangered Species of Wild Fauna and Flora (CITES), among others.

The ESA has been amended numerous times since its enactment. The authorization for funding included in Section 15 of the

ESA expired on October 1, 1992; nevertheless, Congress has appropriated funds in each succeeding fiscal year, and the

ESA’s provisions—including those related to listings, consultations, prohibitions, and penalties—remain in effect.

A long-standing question related to the ESA is whether it effectively achieves its purposes, as outlined in the act. Various

stakeholders have put forth different interpretations on this issue. Some stakeholders have offered, as evidence of the ESA’s

success, the very low rate of extinction for those species listed under the act. Other stakeholders have suggested the ESA has

been ineffective at conservation, noting that recovery is an integral component of success as presumed by the definition of

conservation included within the act—“to bring any endangered or threatened species to the point at which the measures

provided in [the ESA] are no longer necessary”; to support this position, they highlight that only a small number of species

have been delisted due to recovery.

In addition to addressing whether the ESA has been successful at conserving species, stakeholders have raised other issues

related to the act. These issues include, among others, the ESA’s effects on private property and landowners; the ability to

conserve species before it is necessary to list them; the cost of listing species and the resulting economic impacts; the

availability of funding for the ESA; incentives for conservation under the ESA; the states’ role in conserving listed species;

delays in listing, delisting, and reclassifying species under the ESA; and litigation related to the ESA. Given the perennial

nature of these issues and the ESA’s controversial nature, these matters are routinely of concern to Members of Congress.

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The Endangered Species Act: Overview and Implementation

Contents

Introduction ................................................................................................................... 1

Key Provisions of the ESA Addressed in This Report ........................................................... 4

ESA Section 3: Definitions ............................................................................................... 5

Conserve, Conserving, and Conservation ...................................................................... 5

Endangered Species ................................................................................................... 5

Fish or Wildlife ......................................................................................................... 6

Secretary.................................................................................................................. 6

Species .................................................................................................................... 6

Take ........................................................................................................................ 7

Threatened Species .................................................................................................... 7

ESA Section 4: Listing, Critical Habitat, and Recovery ......................................................... 8

Criteria and Factors for Listing .................................................................................... 8

Using the Best Available Science .......................................................................... 11

Process for Listing a Species ..................................................................................... 12

Service-Initiated Listings ..................................................................................... 14

Petitions to List Species ...................................................................................... 14

Rulemaking ....................................................................................................... 15

Candidate Species and Their Conservation ............................................................. 16

Section 4(d) Rules ................................................................................................... 17

Experimental Populations ......................................................................................... 18

Critical Habitat........................................................................................................ 19

Designation of Critical Habitat ............................................................................. 21

Recovery of Listed Species ....................................................................................... 23

Delisting, Uplisting, and Downlisting ......................................................................... 26

ESA Section 5: Land Acquisition..................................................................................... 27

ESA Section 6: Cooperation with States ........................................................................... 27

Management Agreements.......................................................................................... 28

Cooperative Agreements ........................................................................................... 28

ESA Section 7: Interagency Consultation .......................................................................... 31

Section 7 Consultation Process and Biological Opinions ................................................ 31

Exemptions for Section 7 Consultation ....................................................................... 36

ESA Section 9: Prohibitions............................................................................................ 37

ESA Section 10: Exceptions............................................................................................ 38

Permits for Scientific Purposes and Enhancing the Survival of Species ............................ 38

Permits for Incidental Taking of Species and Habitat Conservation Plans ......................... 40

Comparison of Section 10 and Section 7 Consultation ................................................... 41

ESA Section 11: Penalties and Enforcement ...................................................................... 43

Citizen Suits ........................................................................................................... 44

ESA Section 8: Treaties and Conventions Implemented by the ESA ...................................... 45

CITES ................................................................................................................... 45

Appendix I ........................................................................................................ 46

Appendix II ....................................................................................................... 46

Appendix III ...................................................................................................... 46

CITES Implementation ....................................................................................... 47

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CITES Scientific and Management Authorities ....................................................... 47

Western Hemisphere Convention ............................................................................... 49

Appropriations for the ESA ............................................................................................ 49

U.S. Fish and Wildlife Service................................................................................... 50

National Marine Fisheries Service.............................................................................. 51

Concluding Remarks ..................................................................................................... 52

Figures

Figure 1. Distribution of Species Listed Under the Endangered Species Act (ESA), as of

October 2020............................................................................................................... 3

Figure 2. Listing Process Under the ESA .......................................................................... 13

Figure 3. Informal and Formal Consultation Under the ESA ................................................ 33

Tables

Table 1. Time Frame for Recovery Plan Development for FWS and NMFS............................ 25

Table 2. Selected Examples of Federal-State Cooperation Under the ESA.............................. 29

Table 3. Comparison of Section 7 Consultation and Section 10 Permitting Under the ESA ....... 41

Table 4. Enacted FWS Discretionary Appropriations for ESA-Related Activities,

FY2016-FY2021 ........................................................................................................ 50

Table 5. NMFS ESA Funding for FY2016-FY2021 ............................................................ 51

Contacts

Author Information ....................................................................................................... 54

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Introduction

The Endangered Species Act of 1973 (ESA; P.L. 93-205, 87 Stat. 884, 16 U.S.C. §§1531-1544)

aims to conserve species listed as endangered or threatened under the act. The stated purpose of

the ESA is to

Provide a means whereby the ecosystems upon which endangered species and threatened

species depend may be conserved, to provide a program for the conservation of such

endangered species and threatened species, and to take such steps as may be appropriate to

achieve the purposes of the treaties and conventions set forth in subsection (a) of this

section.1

Under the ESA, it is the policy of Congress that all federal agencies shall seek to conserve

threatened and endangered species, use their authorities in furtherance of the ESA, and cooperate

with state and local agencies to resolve water resource issues in concert with conserving

endangered species. 2

The ESA is administered by the U.S. Fish and Wildlife Service (FWS) for terrestrial and

freshwater species, 3 as delegated by the Secretary of the Interior, and by the National Marine

Fisheries Service (NMFS) for marine and anadromous species, 4 as delegated by the Secretary of

Commerce (hereinafter, FWS and NMFS are jointly referenced as the Services). 5 Under the ESA,

domestic and foreign species of animals (both vertebrate and invertebrate) and plants can be listed

as either endangered or threatened, according to an assessment of the risk of their extinction (see

Figure 1.)6 Once a species is listed, the act provides tools to aid its conservation and recovery and

to protect its habitat. Among these tools are the ESA’s prohibition of take (e.g., killing, capturing,

or harming) of endangered species without a permit and its requirement that federal agencies, in

consultation with FWS or NMFS, as applicable, ensure their actions are not likely to jeopardize

the continued existence of listed species or to result in destruction or adverse modification of

designated critical habitat.

The ESA extends to both domestic and foreign species. As of October 2020, a total of 2,363

species of animals and plants were listed as either endangered or threatened; 1,668 of all listed

species occur in the United States and its territories, 7 and the remainder (695 species) occur solely

in other countries. 8 (See Figure 1.) Regulations under the ESA for foreign species largely address

1 Endangered Species Act (ESA; P.L. 93-205, 87 Stat. 884, 16 U.S.C. §§1531-1544) §2, 16 U.S.C. §1531(b).

2 ESA §2(c), 16 U.S.C. §1531(c).

3 For detailed information on the U.S. Fish and Wildlife Service (FWS) program for endangered and threatened species,

see FWS, “Endangered Species,” at http://www.fws.gov/endangered/.

4 T he National Marine Fisheries Service (NMFS), a part of the National Oceanic and Atmospheric Administration

(NOAA), is also sometimes referred to as NOAA Fisheries. Fish are anadromous if they spend most of their lives in salt

water and then swim up a river to spawn. Young anadromo us fish hatch and then swim downstream to grow to

adulthood in the ocean. For example, most salmon and some sturgeon species are anadromous.

5 In addition to the administrative responsibilities assigned to the Secretary of the Interior and the Secretary of

Commerce, the Secretary of Agriculture, pursuant to 16 U.S.C. §1532(15), is responsible for administering the ESA

with regard to the import and export of listed plant species.

6 Domestic species are those species found in the United States, regardless of whether they are also found elsewhere.

Foreign species are species that are not native to the United States and therefore only found abroad.

Listings attributed to the United States include species with populations where the United States shares jurisdiction

with another nation.

8 For updated information, see FWS, “ Environmental Conservation Online System (ECOS) – Listed Species

Summary,” at https://ecos.fws.gov/ecp/report/boxscore.

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The Endangered Species Act: Overview and Implementation

import restrictions and domestic breeding activities within the United States; the ESA generally

does not regulate listed species outside the United States and U.S. territories, because these

species are beyond U.S. jurisdiction. For example, the ESA does not prohibit individuals from

killing listed species in foreign countries. 9

The ESA was passed in 1973, but it was preceded by laws for the preservation and conservation

of endangered species in 1966 and 1969. The Endangered Species Preservation Act (P.L. 89-669),

enacted in 1966, implemented a process for listing native species that were considered

endangered and a program for conserving, protecting, restoring, and propagating those species.

For example, the Endangered Species Preservation Act authorized the Secretary of the Interior to

acquire land as needed to further the conservation of listed species. The first list of endangered

species was promulgated in 1967 and included 78 species, including the grizzly bear, American

alligator, and bald eagle, among others. 10

In 1969, the Endangered Species Conservation Act (P.L. 91-135) amended the Endangered

Species Preservation Act. The Endangered Species Conservation Act provided, among other

things, a list of species in danger of worldwide extinction and expanded protections for species

already listed. The act also called for an international convention or treaty to conserve endangered

species; the United Nations (U.N.) made a similar resolution in 1963. 11 This U.N. resolution laid

the groundwork for a multilateral treaty known as the Convention on International Trade in

Endangered Species of Wild Fauna and Flora (CITES). (See section on “CITES” for more

information.)

In 1973, Congress passed the Endangered Species Act to provide for the conservation of

threatened and endangered species. 12 The ESA has been amended on numerous occasions since it

was enacted. 13 The authorization for funding included in Section 15 of the ESA expired on

October 1, 1992;14 nevertheless, Congress has appropriated funds in each succeeding fiscal year,

and the ESA’s provisions—including those related to listings, consultations, prohibitions, and

penalties—remain in effect.

Any person seeking to hunt such species would be subject only to the laws and regulations of the country where the

species resides. However, the ESA can limit a hunter’s ability to bring back to the United States (i.e., import) any

trophy from such a hunt. For example, individuals are required to obtain appropriate permits prior to importing a trophy

of an ESA-listed species—such as a lion (Panthera leo leo) or an African elephant (Loxodonta africana)—and certain

restrictions apply on how many such trophies can be imported into the United States.

10 Department of the Interior (DOI), “Native Fish and Wildlife: Endangered Species,” 32 Federal Register 4001 (March

11, 1967).

11 International Union for Conservation of Nature, Resolution on Illegal Traffic in Wildlife Species, GA 1963 RES 005,

1963 Nairobi General Assembly, 1963.

12 Congress passed the Endangered Species Act pursuant to its authority under the Commerce Clause to “regulate

Commerce with foreign Nations, and among the several States, and with Indian tribes.” U.S. Const. art. I, §8, cl. 3.

Every U.S. Court of Appeals to consider the issue has upheld Congress’s authority to regulate listed species under that

clause, including with respect to species located only in on e state. See People for the Ethical T reatment of Property

Owners v. U.S. Fish & Wildlife Serv., 852 F.3d 990, 999 -1008 (10 th Cir. 2017) (“Every one of our sister circuits that

has addressed this issue has agreed that regulation of purely intrastate species is an essential part of the ESA’s

regulatory scheme.”); San Luis & Delta-Mendota Water Auth. v. Salazar, 638 F.3d 1163, 1174 -77 (9 th Cir. 2011); Ala.T ombigbee Rivers Coal. v. Kempthorne, 477 F.3d 1250, 1274 (11 th Cir. 2007); GDF Realty Invs. v. Norton, 326 F.3d

622, 640 (5 th Cir. 2003); Rancho Viejo, LLC v. Norton, 323 F.3d 1062, 1080 (D.C. Cir. 2003); Gibbs v. Babbitt, 214

F.3d 483, 487 (4 th Cir. 2000).

13 T he ESA has been amended several times, notably by P.L. 94-359 (1976); P.L. 95-212 (1977) P.L. 95-632 (1978);

P.L. 96-159 (1979); P.L. 96-246 (1980); P.L. 97-79 (1981); P.L. 97-304 (1982); P.L. 98-327 (1984); P.L. 99-659

(1986); P.L. 100-478 (1988); P.L. 100-707 (1988); and P.L. 108-136 (2003).

14 16 U.S.C. §1542.

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The Endangered Species Act: Overview and Implementation

Figure 1. Distribution of Species Listed Under the Endangered Species Act (ESA), as

of October 2020

Source: Congressional Research Service (CRS), from data provided by the U.S. Fish and Wildlife Service (FWS),

October 2020.

Notes: Three foreign plant species and 692 foreign animal species are listed under the Endangered Species Act

(ESA; P.L. 93-205, 87 Stat. 884, 16 U.S.C. §§1531-1544).

Congressional debate over the ESA has addressed a variety of issues. These issues include the

law’s purpose and structure as a whole, specific species and their status and regulation under the

law (e.g., gray wolves)15 , and specific activities and how those activities affect listed species (e.g.,

the effect of water conveyance and pumping in the confluence of the Sacramento and San Joaquin

Rivers’ Delta on the threatened Delta smelt). Many Members of Congress have expressed interest

in how the ESA is implemented, because states—as well as American Samoa, Guam, the

Northern Mariana Islands, 16 Puerto Rico, the Virgin Islands, outlying Islands in the Pacific and

For more information on the gray wolf, see CRS Report R46184, The Gray Wolf Under the Endangered Species Act

(ESA): A Case Study in Listing and Delisting Challenges, by Erin H. Ward.

16 16 U.S.C. §1532(17) and 50 C.F.R. §81.1(i) both define state in the context of the ESA to be “any of the several

States, the District of Columbia, the Commonwealth of Puerto Rico, American Samoa, the Virgin Islands, Guam, and

the T rust T erritory of the Pacific Islands.” However, the T rust T erritory of the Pacific I slands has since terminated, and

of the trustees, only the Commonwealth of the Northern Mariana Islands (CNMI) is still in political union with the

United States. For more information, see 48 U.S.C. §1681 and 48 U.S.C. §§1801 et seq. T he covenant between t he

United States and the CNMI, which established the political union (P.L. 94-241, as amended), provided for the

applicability of the ESA to the CNMI.

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The Endangered Species Act: Overview and Implementation

the Caribbean, and Washington, DC—have species that are, or may be in the future, listed under

the act. 17 Some Members have supported efforts to amend the ESA to increase the authorization

of funding for the act, particularly to address the backlog of species the Services have determined

warrant listing and to improve recovery efforts; to focus efforts under the act more on species

recovery rather than primarily on protection; to elevate the role of states in implementing the act;

and to provide increased regulatory certainty to landowners to incentivize conservation activities,

among other things. 18 Some other Members may share the sentiment of reauthorizing the ESA but

may have other priorities, such as increasing appropriations for implementing the ESA. 19

Congress also may be interested in broader issues surrounding the ESA and oversight of the act’s

implementation, primarily because some stakeholders perceive the ESA and the conservation of

listed species, at times, as an obstacle to economic development. 20 For example, some see the

ESA as a primary driver of or exacerbating factor in resource controversies. Examples of resource

controversies where the ESA may be a factor include the allocation of water supplies through the

Central Valley Project in California and the conservation of threatened Delta smelt (Hypomesus

transpacificus), listed under the ESA, and Northwest timber harvests, which balance logging,

recreation, and sport fishing with ecosystem protection and the conservation of listed species,

such as the northern spotted owl (Strix occidentalis caurina). In contrast, some stakeholders argue

the ESA is not a primary factor in resource controversies and may be one of several factors

contributing to such issues. 21

This report discusses selected provisions of the ESA and selected federal regulations that

implement the ESA. The discussion is not comprehensive. It includes references to other CRS

products that provide in-depth discussion of some provisions.

Key Provisions of the ESA Addressed in This Report

This report discusses several major provisions of the ESA. It addresses the following sections of

the act, generally in the order they appear in the U.S. Code. 22

For an accounting of the number of species listed as threatened or endangered by state, see FWS, Environmental

Conservation Online System (ECOS), “ Listed Species Believed to or Known to Occur in Each State,” at

https://ecos.fws.gov/ecp/report/species-listings-by-state-totals?statusCategory=Listed. In addition to the federal ESA,

many states have enacted endangered species acts (though the naming of these acts may differ) to list and conserve

species under state law. When discussing the ESA or listed species in this report, only the federal ESA is being

referenced.

For example, see statement of Sen. John Barrasso, U.S. Congress, Senate Committee on Environment and Public

Works, Modernizing the Endangered Species Act: Legislative Hearing on S.4589, the Endangered Species Act

Amendments of 2020, 116 th Cong., 2 nd sess., September 23, 2020.

19 For example, see statement of Sen. T homas R. Carper, U.S. Congress, Senate Committee on Environment and Public

Works, Modernizing the Endangered Species Act: Legislative Hearing on S.4589, the Endangered Species Act

Amendments of 2020, 116 th Cong., 2 nd sess., September 23, 2020.

20 For example, see A. J. Hoffman, M. H. Bazerman, and S. L. Yaffee, “Balancing Business Interests and Endangered

Species Protection,” MIT Sloan Management Review, vol. 39, no. 1 (Fall 1997), pp. 59-73.

21 T he timing and amount of water diverted for agricultural and municipal needs in the Central Valley of California is a

complex issue that involves several factors, including listed species under the ESA. Scientists argue the issue is not

derived solely from the ESA but also involves water quality factors, toxins, lawsuits, and water supply, among other

factors. See Committee on Sustainable Water and Environmental Management in the California Bay -Delta, Sustainable

Water and Environmental Management in the California Bay-Delta, National Research Council, 2012.

Section 2 of the ESA (16 U.S.C. §1531), which addresses congressional findings and declaration of purposes and

policy, is discussed briefly in the “ Introduction” to this report. For more information on legal aspects of the ESA,

namely the listing process, please see CRS Report R46184, The Gray Wolf Under the Endangered Species Act (ESA): A

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The Endangered Species Act: Overview and Implementation



Section 3: Definitions

Section 4: Listing



Section 5: Land Acquisition

Section 6: Cooperation with States



Section 7: Interagency Cooperation and Consultation

Section 9: Prohibitions



Section 10: Exceptions



Section 11: Penalties and Enforcement

Section 8: Convention Implementation



Section 15: Authorization of Appropriations

Additional relevant definitions and implementing regulations are discussed in the applicable

sections.

ESA Section 3: Definitions

Section 3 of the ESA defines terms for purposes of the act.23 Selected definitions from the ESA

are discussed below. Other definitions under the ESA are discussed later in this report, where they

are most relevant.

Conserve, Conserving, and Conservation

The terms conserve, conserving, and conservation mean to use and the use of all methods and

actions to bring an endangered or threatened species to the point where the protections of and

measures within the ESA are no longer necessary for the species. The definition states that these

methods and measures include activities associated with scientific resources management (e.g.,

research, census, law enforcement, habitat acquisition and maintenance, propagation,

transplanting, and, in limited circumstances, regulated taking). 24

Endangered Species

The term endangered species refers to those species—as defined by the ESA—that are “in danger

of extinction throughout all or a significant portion of its range.” Although the definition of

species includes animals (both vertebrates and invertebrates) and plants, the definition of

endangered species precludes listing certain insect species determined by the Secretary of the

Interior or the Secretary of Commerce, as appropriate, to be pests.25

Case Study in Listing and Delisting Challenges, by Erin H. Ward.

23 ESA §3, 16 U.S.C. §1532.

ESA §3(3), 16 U.S.C. §1532(3).

25 ESA §3(6), 16 U.S.C. §1532(6). In this report, references to the Secretary are to the Secretary of the Interior or the

Secretary of Commerce, as appropriate, unless otherwise stated. See “ Secretary” for more information.

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The Endangered Species Act: Overview and Implementation

Fish or Wildlife

The term fish or wildlife refers to any member of the animal kingdom, including mammals, fish,

birds, amphibians, reptiles, mollusks, crustacean, arthropod, or other invertebrates (e.g., insects

such as the rusty patched bumble bee [Bombus affinis] and the American burying beetle

[Nicrophorus americanus]). It “includes any part, product, egg, or offspring thereof, or the dead

body or parts thereof.”26

Secretary

In the ESA, the term the Secretary means the Secretary of the Interior or the Secretary of

Commerce, as appropriate, except that it also could refer to the Secretary of Agriculture with

respect to enforcement provisions in the act and CITES as they relate to terrestrial plants (all

references to Secretary in this report are to the Secretary of the Interior or the Secretary of

Commerce, as appropriate, unless otherwise stated).27

The Secretary of the Interior, through FWS, generally manages and administers the ESA with

regard to terrestrial, freshwater, and catadromous species. 28 However, marine and anadromous

species generally are the responsibility of the Secretary of Commerce, acting through NMFS.

Management of marine mammals under the ESA is split between the Services, 29 and sea turtles

are managed jointly by both Services. 30 The law assigns several key roles to the Secretary of the

Interior and provides for the relationship of the Secretary of the Interior and the Secretary of

Commerce and their respective powers. For example, the Secretary of the Interior is responsible

for listing and delisting species. In the case of species administered by NMFS, the Secretary of

Commerce conveys listing, reclassification, and delisting determinations to the Secretary of the

Interior. Per the ESA, the Secretary of the Interior is instructed to list or uplist (i.e., reclassify a

species from being listed as threatened to being listed as endangered) a species under the

Secretary of Commerce’s purview after being informed of such determination by the Secretary of

Commerce. Downlisting (i.e., reclassifying a species from being listed as endangered to being

listed as threatened) and delisting determinations for species managed by NMFS are implemented

if the Secretary of the Interior concurs with the Secretary of Commerce’s recommendation. 31

Species

The ESA defines species to include any subspecies of fish, wildlife, or plant and any distinct

population segment (DPS) of vertebrate fish or wildlife species that interbreeds when mature.32

Accordingly, the Secretary can list a species (as used in taxonomy; i.e., Genus species), a

subspecies (i.e., Genus species subspecies), or a DPS as a “species” under the act. The Secretary

26 ESA §3(8), 16 U.S.C. §1532(8).

27 ESA §3(15), 16 U.S.C. §1532(15).

28 Fish are catadromous if they are born in salt water, migrate to fresh water to mature, and then migrate back to salt

water to spawn. T he American eel (Anguilla rostrate) can be catadromous, though the species also can remain in

marine or brackish water during maturation.

29 For more information, see FWS, International Affairs, “ Marine Mammals,” at https://www.fws.gov/international/

animals/marine-mammals.html.

30 50 C.F.R. §17.11.

ESA §(2)(a)(2)(C), 16 U.S.C. §1533(a)(2)(C).

32 A distinct population segment (DPS) under the ESA refers to a population of a species that is a discrete and

significant segment of the species as a whole.

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The Endangered Species Act: Overview and Implementation

cannot, however, list a group of organisms that does not qualify as one of these three categories.

The term DPS is specific to the act rather than borrowed from biology or taxonomy. It has been

interpreted by the Services in guidance and in rules promulgated under the ESA, as described in

the text box on Distinct Population Segments.

Take

The ESA defines the term take to mean “to harass, harm, pursue, hunt, shoot, wound, kill, trap,

capture, or collect, or to attempt to engage in any such conduct.”33 FWS defined the terms harass

and harm for species under its management through regulation at 50 C.F.R. §17.3, and NMFS

similarly defined harm through regulation at 50 C.F.R. §222.102. The Services both define harm

to include significant habitat modification or degradation that kills or injures wildlife. A group of

landholders and parties with interests in forestry challenged FWS’s inclusion of modification or

degradation of habitat as an overly expansive interpretation of the statute. 34 The parties argued

that harm should be limited to using force directly against a species. 35 The Supreme Court held

that it was reasonable for the Secretary to interpret harm to include habitat modification or

degradation that results in actual injury or death of a listed species. 36

Threatened Species

The term threatened species means any species, as defined by the ESA, that is likely to become

an endangered species within the foreseeable future (see text box below on “Foreseeable Future

in Regulations”) throughout all or a significant portion of its range. 37

Foreseeable Future in Regulations

The FWS and the NMFS defined the term foreseeable future in regulations for the first time in a final rule

promulgated in August 2019 (84 Federal Register 45020). Before this rule, the Services had interpreted the

foreseeable future on a case-by-case basis in the course of promulgating listing rules for particular species and for

purposes of related litigation.

Under the final rule, the Services define foreseeable future as extending “only so far into the future as the Services

can reasonably determine that both the future threats and the species’ responses to those threats are likely.” The

Services explain that likely means more likely than not. Although the final rule provides a definition for the term

foreseeable future, the Services stated they still would determine how this definition applies to a particular species

on a case-by-case basis based on the best available data. The Services stated they intend to take into account lifehistory characteristics, threat-projection time frames, and environmental variability to determine how foreseeable

future applies for a given species.

The Services and certain stakeholders have characterized the definition as generally codifying the Services’ existing

practices when determining the foreseeable future in listing decisions. Other stakeholders have expressed

concerns that this definition of foreseeable future would limit consideration of long -term projected threats,

including from climate change (e.g., habitat changes or sea-level rise) and could limit the use of population

modeling to evaluate the fate of a species under future conditions. The Services will have discretion to evaluate

these and other factors when considering which threats and responses are likely in implementing this definition.

Sources: 50 C.F.R. §424.11(d). Rebecca Barho and Brooke Wahlberg, “Expert Analysis ESA Rule Changes Less

Drastic Than Critics Claim,” Law360 (August 29, 2019), at https://www.law360.com/transportation/articles/

1192657/esa-rule-changes-less-drastic-than-critics-claim; Jake Li, “Last Week’s Endangered Species Regulations:

33 ESA §3(19), 16 U.S.C. §1532(19).

34 Babbitt v. Sweet Home Chapter of Communities for a Great Oregon, 515 U.S. 687, 692-93 (1995). Hereinafter

referred to as “Sweet Home,” 1995.

35 “Sweet Home,” 1995 at 697-98.

36 “Sweet Home,” 1995 at 697-704.

37 ESA §3(20), 16 U.S.C. §1532(20).

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What Really Happened?” Environmental Policy and Innovation Center, August 20, 2019, at

http://policyinnovation.org/the-real-story-on-the-new-endangered-species-act-rules/.

Note: For more information on listing species under the Endangered Species Act (ESA; P.L. 93-205, 87 Stat. 884,

16 U.S.C. §§1531-1544) due to climate change, see CRS Report R45926, The Endangered Species Act and Climate

Change: Selected Legal Issues, by Linda Tsang.

ESA Section 4: Listing, Critical Habitat, and

Recovery

The Services may list a species as endangered or threatened under the ESA pursuant to Section 4

of the act and the accompanying regulations. 38 Under the ESA, they may also reclassify species

through uplisting or downlisting, or delist them.

Criteria and Factors for Listing

The Services may list a species as endangered or threatened if one or more ESA factors would

render the species in danger of extinction (endangered) or likely to become so in the foreseeable

future (threatened) in all or a significant portion of its range. 39 The ESA factors are

1. The present or threatened destruction, modification, or curtailment of the species’

habitat or range

2. The species’ overuse for commercial, recreational, scientific, or educational

purposes

3. Disease or predation affecting the species

4. Inadequate existing regulatory mechanisms protecting the species

5. Other natural or man-made factors affecting the species’ continued existence40

The ESA addresses both anthropogenic and natural factors that could affect a species’ viability.

For example, a dwindling species subject to natural stressors could be listed under the ESA

pursuant to the third factor. However, a species’ small population alone may not necessarily

warrant its listing. Courts have held that the Services may need to weigh other considerations,

such as the reasons for the small population size, if and the rate at which population size is

changing, and the potential implications of small population size on the species’ risk of

extinction. 41 If the Secretary determines a species is threatened or endangered based on any ESA

factor, the Secretary is required to list the species. 42

The ESA provides for listing species, subspecies, or, for vertebrate fish and wildlife, distinct

population segments (DPS). Typically, a DPS is described in geographic terms (e.g., the Northern

Rocky Mountain DPS for gray wolves, Canis lupis). Depending on how a species is listed, ESA

protections for fish and wildlife species may extend to (1) the species as a whole, including all

subspecies, if the taxonomic species is listed; (2) the subspecies, if the subspecies is listed; or (3)

ESA §4, 16 U.S.C. §1533.

39 ESA §3(6), (20), 16 U.S.C. §1532(6), (20).

40 ESA §4(a)(1), 16 U.S.C. §1533(a)(1).

See, for example, Ctr. for Biological Diversity v. Zinke, 900 F.3d 1053, 1073 -74 (9 th Cir. 2018); Sw. Ctr. for

Biological Diversity v. Norton, Civ. Action No. 98-934, 2002 WL 1733618, at *13 (D D.C. July 29, 2002).

42 ESA §4(a)(1), 16 U.S.C. §1533(a)(1).

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an identified population of the taxonomic species or subspecies when a DPS is listed. Protections

also may differ depending on whether a species is listed as endangered or threatened (see

“Section 4(d) Rule”). More limited protections are available for plants (see “Section 9:

Prohibitions”). 43 The ESA does not protect organisms considered neither animal nor plant (e.g.,

Eubacteria, archaea, and viruses).

Distinct Population Segments

Under the ESA, a distinct population segment (DPS) refers to a vertebrate fish or wildlife population that is a discrete

and significant segment of a species as a whole. (16 U.S.C. §1532(16)). For purposes of this discussion, species

refers to a taxonomic species rather than a species as defined by the ESA. Discreteness is based on the

population’s separation from other populations of the species and may be “the consequence of physical,

physiological, ecological, or behavioral factors.” The Services evaluate significance based on biological and

ecological factors. To be designated significant, the Services consider factors that include, but are not limited to,

the following:



The DPS exists in an ecological setting that is unusual or unique for the species.



Evidence exists that loss of the DPS would lead to a gap in the species’ range.



Evidence exists that the DPS represents the species’ only surviving natural population, regardless of whether

the species is abundant outside its historic range as an introduced population.



The DPS is genetically different from the species’ other populations.

By listing, reclassifying, or delisting a DPS, the Services can identify and either heighten or lower protections for a

distinct population of a species based on the best available science. For example, when a species is listed as

threatened, a portion of the species identified as a DPS may be listed as endangered while the rest of the taxon

remains threatened. In this way, the Services can use a DPS to address a species’ decline in a distinct region when

listing the entire species is unwarranted. In their policy, the Services have noted that identifying a DPS might

enable less costly protection and recovery measures than adopting measures across the species’ full geographic

range. Alternatively, a DPS may be listed as threatened when the remainder of the species is listed as endangered,

or the Services may list a DPS as threatened or endangered and not list the remainder of the species.

Congress first included DPS as part of the ESA species definition in 1978. Prior to 1978, the ESA included “any

other group of fish or wildlife of the same species or smaller taxa in common spatial arrangement that interbreed

when mature” as part of the ESA species definition. In 1996, the Services promulgated a policy describing how

they would evaluate whether a population qualified as a DPS.

NMFS developed the concept of evolutionarily significant units (ESUs) as a way to interpret the “distinct population

segment” language in Section 3(16) of the ESA for Pacific salmon. ESUs generally include multiple (often as many as

20 to 30) populations or stocks and are intended to identify groups of salmon populations that can be listed as

threatened or endangered under the ESA. NMFS’s policy states that to qualify as an ESU, a stock must be

reproductively isolated from other population units and must represent a genetically important or significant

component of the species. The ESU policy does not impose specific scientific criteria and applies only to Pacific

salmon population segments. Whether hatchery fish may be assigned to an ESU, thereby augmenting an ESU’s

population count, has been particularly controversial. For example, see CRS Report R40169, Endangered Species

Act Litigation Regarding Columbia Basin Salmon and Steelhead, by Stephen P. Mulligan and Harold F. Upton.

Sources: FWS and NMFS, “Policy Regarding the Recognition of Distinct Vertebrate Population Segment s Under

the Endangered Species Act,” 61 Federal Register 4722-4725, February 7, 1996; NMFS, “Policy on Applying the

Definition of Species Under the Endangered Species Act to Pacific Salmon,” 56 Federal Register 58612, November

20, 1991; D. S. Pennock and W. W. Dimmick, “Critique of the Evolutionarily Significant Unit as a Definition for

Distinct Population Segments Under the U.S. Endangered Species Act,” Conservation Biology, v. 11 (1997), pp. 611619.

The Services’ interpretation of “all or a significant portion of its range” has changed over time,

generally in response to adverse court decisions overturning listing rules. 44 In 2014, the Services

ESA §9(a)(2), 16 U.S.C. §1538(a)(2).

44 See, for example, Defs. of Wildlife v. Norton, 258 F.3d 1136, 1141-42 (9 th Cir. 2001); Defs. of Wildlife v. Salazar,

729 F. Supp. 2d 1207, 1217-28 (D. Mont. 2010).

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issued a joint policy interpreting “all or a significant portion of its range.”45 Under the policy, the

Services interpret the phrase as providing two independent bases for listing a species: (1) when

the species is endangered or threatened in all of its range or (2) when the species is endangered or

threatened across a significant portion of its range. 46 The Services interpret the range of a species

to mean the area that the species currently occupies, not its historical range;47 at least one court

has upheld this interpretation as reasonable. 48 The Services have, however, accounted for lost

historical range when evaluating the factors threatening a species. 49

The 2014 policy also explained how the Services would determine whether a portion of a species’

range was significant, but district courts have since overturned that definition. 50 Under the policy,

the Services considered a portion of a species’ range to be significant if “the species is not

currently endangered or threatened throughout its range, but the portion’s contribution to the

viability of the species is so important that, without the members in that portion, the species

would be in danger of extinction, or likely to become so in the foreseeable future, throughout all

of its range.”51 District courts invalidated this interpretation, because they concluded it rendered

the phrase “a significant portion of its range” superfluous. 52 The courts reasoned that if a species

would be endangered or threatened in the areas outside the “significant portion” of the range and

the species is endangered or threatened within the significant portion of the range, then the

species is necessarily endangered or threatened throughout its entire range. 53 The Services

therefore could never list a species as endangered or threatened in a significant portion of its

range under their interpretation—the species would always need to be endangered or threatened

in all of its range to be listed. The courts concluded that the Services used this interpretation to

give the phrase “a significant portion of its range” “as little substantive effect as possible,” which

was “arguably at odds with the conservation purposes of the ESA,” and that the Services

impermissibly limited the phrase “to situations in which it is unnecessary.”54

In a 2019 proposed rule to delist the gray wolf, FWS acknowledged that the Services’

interpretation of the term significant in the policy no longer applies. 55 FWS proposed to identify

any portion of a species’ range “that could be significant under any reasonable definition of

‘significant’ that relates to the conservation of the [species proposed for listing].”56 The Services

45 FWS and NOAA, “Final Policy on Interpretation of the Phrase ‘Significant Portion of Its Range’ in the Endangered

Species Act’s Definitions of ‘Endangered Species’ and ‘T hreatened Species’”; Final Rule, 79 Federal Register 3757837612, July 1, 2014.

46 79 Federal Register 37580; see also 77 Federal Register 55530 and 55601, September 10, 2012.

47 79 Federal Register 37583-37585.

48 See, for example, Humane Soc’y of U.S. v. Zinke, 865 F.3d 85, 603 -04 (D.C. Cir. 2017).

49 See, for example, 84 Federal Register 9648 and 9658, March 15, 2019.

50 Desert Survivors v. U.S. Dep’t of the Interior, No. 16 -cv-01165-JCS, at *7 (N.D. Cal. Aug. 24, 2018) (issuing

nationwide injunction vacating and setting aside definition of “significant” under Services policy). See also Desert

Survivors v. U.S. Dep’t of the Interior, 321 F. Supp. 3d 1011, 1073 -74 (N.D. Cal. 2018) (order granting summary

judgment to plaintiffs); Ctr. for Biological Diversity v. Jewell, 248 F. Supp. 3d 946, 956 (D. Ariz. 2017).

51 79 Federal Register at 37579.

Ctr. for Biological Diversity, 248 F. Supp. 3d at 956; Desert Survivors, 321 F. Supp. 3d at 1073-74.

53 Ctr. for Biological Diversity, 248 F. Supp. 3d at 956; see also Desert Survivors, 321 F. Supp. 3d at 1073-74 (order

granting summary judgment to plaintiffs).

54 Ctr. for Biological Diversity, 248 F. Supp. 3d at 958.

55 84 Federal Register 9648 and 9684, March 15, 2019.

56 84 Federal Register 9684, March 15, 2019.

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have not yet revised their policy to interpret the term significant to account for the court’s

decision.

Using the Best Available Science

Pursuant to statutory requirements, the Secretary must decide whether to list species based only

on the best available scientific and commercial data, using information to which the agency has

access and information obtained from the public through the agency rulemaking process. 57 The

statute does not define the phrase “best available scientific and commercial data,” and the

Services have not interpreted this phrase through regulation. Courts, however, have reviewed the

use of science and data in ESA decisions. One court held that the statutory phrase does not

require, and hence a court cannot order, the Services to conduct additional studies to obtain

missing data and that the agency must rely on inconclusive or uncertain information if that is the

best data available at the time of a listing decision. 58 However, the agency cannot rely on data

that its own scientists agree is inaccurate. 59 The relevant agency cannot ignore available

biological information or commercial data, especially if that information is the most current or is

scientifically superior to other information. 60

A court also said that “the ‘best scientific and commercial data available’ is not a standard of

absolute certainty, and [is] a fact that reflects Congress’ intent that the FWS take conservation

measures before a species is ‘conclusively’ headed for extinction.”61 The fact that the studies on

which the Services rely are imperfect—so long as they are not inaccurate—does not undermine

those authorities as the best scientific data available; “the Service must utilize the best scientific

... data available, not the best scientific data possible.”62

The ESA expressly requires the Services to make listing determinations “solely on the basis of the

best scientific and commercial data available.”63 Congress added the word solely in the 1982

amendments to the ESA to clarify that the determination of endangered or threatened status was

intended to be made without reference to its potential economic impacts. 64 In discussing the

addition of the word solely, a committee report stated the word 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.”65 The committee further stated that it “strongly believes that economic considerations

ESA §4(b)(1)(A), 16 U.S.C. §1534(b)(1)(A). Formally, this determination is made by the Secretary of the Interior,

but for species under NMFS’s jurisdiction, the determination to list, delist, or change the status of a species cannot be

made without “prior favorable determination ... by the Secretary of Commerce.” 16 U.S.C. §1533(a)(2)(C).

Sw. Ctr. for Biological Diversity v. Babbitt , 215 F.3d 58 (D.C. Cir. 2000); see also Las Vegas v. Lujan, 891 F.2d

927, 933 (D.C. Cir. 1989); Defs. of Wildlife v. Jewell, 176 F. Supp. 3d 975, 999-1000 (D. Mont. 2016).

59 Ctr. for Biological Diversity v. Lohn, 296 F. Supp. 2d 1223 n.13 (W.D. Wash. 2003), vacated on other grounds by

Ctr. for Biological Diversity v. Lohn, 511 F.3d 960 (9 th Cir. 2007).

Am. Wildlands v. Kempt horne, 530 F.3d 991, 998 (D.C. Cir. 2008); Sw. Ctr. for Biological Diversity v. Babbitt , 926

F. Supp. 920, 927 (D. Ariz. 1996); Las Vegas, 891 F.2d at 933.

61 Defs. of Wildlife v. Babbitt , 958 F. Supp. 670, 679-80 (D.D.C. 1997); see also Defs. of Wildlife, 176 F. Supp. 3d at

999-1000.

Bldg. Indus. Ass’n of Superior Cal. v. Norton, 247 F.3d 1241, 1246-67 (D.C. Cir. 2001), cert. denied 534 U.S. 1108;

see also San Luis & Delta-Mendota Water Auth. v. Jewell, 747 F.3d 581, 602 (9 th Cir. 2014); Defs. of Wildlife, 176 F.

Supp. 3d at 999-1000 (emphasis added).

63 ESA §4(b)(1)(A), 16 U.S.C. §1533(b)(1)(A) (emphasis added).

P.L. 97-304, 96 Stat. 1411.

65 H.Rept. 97-567, pp. 19-20. T he conference report (H.Rept. 97-835, p. 19) also confirms that it was the intent of both

chambers that economic factors would not play a role in the listing of species for protection.

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have no relevance to determinations regarding the [listing] status of species,” and that applying

economic criteria to the listing process is prohibited by the inclusion of the word solely in the

legislation. 66

As part of a listing decision, the Secretary may not consider the economic effects that listing may

have, such as delaying or modifying building projects in the area where the species occurs. 67 In a

2019 final rule, the Services amended the regulations implementing listing decisions under the

ESA to no longer prohibit referencing the estimated economic costs of listing a species in the

listing decision. While acknowledging that economic costs cannot be a factor in whether to list a

species, the rule states that these costs can be reported in the listing decision to provide

transparency to stakeholders and be used for planning purposes. 68

In summary, under the ESA, whether a species is endangered or threatened is a scientific decision

that the Services make based on the best available scientific and commercial data. Once a species

is listed as threatened or endangered, the Services must consider economics for critical habitat

designations and may consider economic factors when suggesting reasonable and prudent

alternatives. 69

Process for Listing a Species

Listing a species, as well as delisting or reclassifying (i.e., uplisting or downlisting), may be

initiated by the Services or through a petition process. The listing process is outlined by statute

and further specified in implementing regulations. 70 This section discusses the process for listing

a species under the ESA (see Figure 2).

66 H.Rept. 97-567, pp. 19-20.

67 However, economic considerations, among other factors, are to be incorporated into critical habitat determinations.

ESA §4(b)(2), 16 U.S.C. §1533(b)(2). In addition to economic considerations, the ESA requires consideration of “ the

impact on national security, and any other relevant impact, of specifying any particular area as critical habitat .”

FWS and NOAA, “Endangered and T hreatened Wildlife and Plants: Regulations for Listing Species and Designating

Critical Habitat,” 84 Federal Register 45020-45053, August 27, 2019.

Reasonable and prudent alternatives refer to alternative actions that can be implemented consistent with the intended

purpose of the action and authority and jurisdiction of the action agency; is economically and technologically feasible;

and that the Services believe will avoid the likelihood of jeopardizing the continued existence of listed species or result

in the destruction or adverse modification of its critical habitat. 50 C.F.R. §402.02. See section on “ESA Section 7:

Interagency Consultation” for more information.

70 ESA §4, 16 U.S.C. §1533, and 50 C.F.R. §424.

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Figure 2. Listing Process Under the ESA

Source: Adapted from FWS, Endangered Species Program, “Listing a Species as a Threatened or Endangered

Species, August 2016, at https://www.fws.gov/endangered/esa-library/pdf/listing.pdf.

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Service-Initiated Listings

As delegated by the Secretaries, the Services, on their own initiative, may propose to list a species

under the ESA. When considering listing a species, the Services conduct status surveys to assess

the species’ viability. The process for Service-initiated reclassification is discussed in “Delisting,

Uplisting, and Downlisting,” below.

Petitions to List Species

Any person may petition the Services to list a species under the ESA. 71 Person is defined under

the ESA as

an individual, corporation, partnership, trust, association, or any other private entity; or any

officer, employee, agent, department, or instrumentality of the Federal Government, of any

State, municipality, or political subdivision of a State, or of any foreign government; any

State, municipality, or political subdivision of a State; or any other entity subject to the

jurisdiction of the United States.72

Any person also may petition for a species to be reclassified or delisted.

The ESA requires that, within 90 days of receiving a petition to list a species, “to the maximum

extent practicable,” the Secretary make an initial determination as to “whether the petition

presents substantial scientific or commercial information” to indicate the requested action “may

be warranted.”73 If the relevant Service determines the petition may be warranted, the agency

conducts a status review of the species pursuant to the criteria for listing a species. The Service

has 12 months after receiving the petition to conduct the status review and make a final

determination on whether the petitioned action is warranted.

Lawsuits for Failing to Meet Listing Deadlines

Petitioners have sued the Services for failing to meet the 90-day and 12-month deadlines, particularly as the

number of petitions has increased. (See section on “Citizen Suits,” below.) Courts have rejected the argument

that the 90-day deadline establishes a “mandatory, nondiscretionary duty” for the Services, determining instead

that the phrase “to the maximum extent practicable” allows for “at least a ‘limited exception’” to that time limit.

How much discretion this language affords has been a point of dispute between plaintiffs and the Services, with

courts generally deferring to the agency’s explanation for its allocation of resources—provided it is reasonable.

Courts have held, however, that the 12-month statutory deadline is mandatory.

Although the 12-month deadline is statutorily required, the Services frequently have missed this deadline. In

February 2020, a stakeholder filed a lawsuit alleging the Services had missed the 12-month deadline for petitions to

list 231 species.

Before the court reaches a final determination on addressing deadlines for listing, the Services and parties may use

voluntary settlements to agree to alternative time frames for addressing petitions or listing species. For example,

several of these lawsuits were settled in 2011, setting deadlines for listing determinations on hundreds of species.

Sources: Biodiversity Legal Found. v. Babbitt, 146 F.3d 1249, 1253 -57 (10 th Cir. 1998); see also Inst. for Wildlife

Prot. v. Norton, 303 F. Supp. 2d 1175, 1177-78 (W.D. Wash. 2003); Ctr. for Biological Diversity v. Norton, 208 F.

Supp. 2d 1044, 1049 (N.D. Cal. 2002); Ctr. for Biological Diversity v. Norton, 254 F.3d 833, 837 (9 th Cir. 2001);

Friends of Animals v. Salazar, 670 F. Supp. 2d 7, 12-13 (D.D.C. 2009); Biodiversity Legal Found. v. Norton, 180 F.

Supp. 2d 7, 9 (D.D.C. 2001); FWS, “Improving ESA Implementation: Listing Workplan Overview,” at

https://www.fws.gov/endangered/improving_ESA/listing_workplan.html.

71 ESA §4(b)(3), 16 U.S.C. §1533(b)(3).

72 ESA §3(13), 16 U.S.C. §1532(13).

73 ESA §4(b)(3)(A), 416 U.S.C. §1533(b)(3)(A).

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In May 2019, FWS issued a National Listing Workplan to prioritize its listing and critical habitat

designations over a five-year period. 74 Through the workplan, which FWS intended to update

regularly, FWS aims to provide stakeholders with greater clarity and predictability about the

timing of listing determinations in order to encourage proactive conservation actions that may

avoid the need for federal protection. The workplan includes nearly 250 species. 75

The status review for listing a species results in one of three findings: (1) the petitioned action is

not warranted; (2) the petitioned action is warranted and a listing proposal will be promptly

published; or (3) the petitioned action is warranted but precluded by higher-priority species for

listing. 76 If the Secretary concludes the action is warranted, the Service prepares a proposed rule

to list the species. The Services also may consider petitions for multiple species that share a

common ecosystem.

If a species is proposed for listing under the ESA, the Secretary must do the following:



Publish the proposed regulation in the Federal Register and solicit public

comments over a 60-day comment period

Seek independent peer review and scientific analysis from species specialists

Give notice to state agencies and counties where the species is thought to occur

and invite those governments to submit comments on the proposal

Give notice, if practical, to foreign countries where the species occurs or whose

citizens harvest the species on the high seas



Notify relevant professional societies

Publish a summary of the regulation locally where the species is found



Upon request, hold a public hearing77

Alternatively, a warranted but precluded finding means the Services will not propose to list the

species at that time and the species instead becomes a candidate species (see “Candidate Species

and Their Conservation” for more information). 78 The ESA requires the Services to reevaluate

candidate species annually until a listing rule is proposed or a not warranted finding is made. (See

Figure 2.)

Rulemaking

The Services initiate an Administrative Procedure Act (APA) rulemaking to list a species. 79 To

issue a new rule (e.g., a listing rule) under the APA, the Services must publish notice of the

proposed rule in the Federal Register, provide a period for the public to comment on the

74 FWS, National Listing Workplan, May 2019, at https://www.fws.gov/endangered/esa-library/pdf/5-

Year%20Listing%20Workplan%20May%20Version.pdf.

FWS, National Listing Workplan, May 2019, at https://www.fws.gov/endangered/esa-library/pdf/5Year%20Listing%20Workplan%20May%20Version.pdf.

ESA §4(b)(3), 16 U.S.C. §1533(b)(3).

77 ESA §4(b)(5), 16 U.S.C. §1533(b)(5).

78 See “ Candidate Species and T heir Conservation” section in this report.

79 5 U.S.C. §§551 et seq.

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proposed rule and submit data, and publish the final rule with an explanation of its basis and

purpose. 80 The Services also may allow for public hearings on the proposed rule. 81

A species is listed, reclassified, or delisted through a final rule published in the Federal Register.

In accordance with the Services’ regulations, the rule must contain a summary of comments and

recommendations received in response to the proposed rule, summaries of the data on which the

rule is based, the relationship of the data to the final rule, and a summary of the factors affecting

the species, among other things. 82 If a state agency submits comments disagreeing with a

proposed rule and the Secretary finalizes the rule in conflict with state comments, then the

Secretary is to provide the state agency with a justification for adopting a rule not consistent with

state comments. 83

Candidate Species and Their Conservation

A candidate species is “any species being considered by the Secretary for listing as an

endangered or threatened species, but not yet the subject of a proposed rule.”84 FWS elaborates on

this definition by stating that candidate species are those for which the relevant Service has

sufficient information to propose the species as threatened or endangered, but developing a

proposal for listing is precluded by other, higher-priority listing activities, often referred to as

warranted but precluded. 85 As noted, candidate species may result from either a Service-initiated

review of a species or the petition process. Candidate species have no statutory protection. The

status of candidate species must be reviewed annually until one of the Services issues a proposed

rule for listing the species or the Services determine that listing is no longer warranted.

While a species is a candidate for listing, federal agencies and other entities may undertake

strategic activities to improve its status to avoid a listing proposal at some future date. For

example, federal agencies may develop a candidate conservation agreement with FWS or NMFS

to take specified actions to conserve a species. 86 Nonfederal landowners may pursue a candidate

conservation agreement with assurances (CCAA). 87 Under a CCAA, a landowner may agree to

carry out certain actions intended to conserve the species, with the assurance that, as long as the

agreed actions are carried out, the landowner will not be required to change those activities if any

candidate species covered by the CCAA is subsequently listed as threatened or endangered.

According to FWS, early conservation of candidate species generally increases management

options and flexibility for landowners, lowers the cost of recovery for the species, and reduces the

likelihood that more restrictive land use measures will be necessary in the future (i.e., if the

species continues to decline and is listed). 88

80 5 U.S.C. §553.

81 5 U.S.C. §553.

82 50 C.F.R. §424.18.

83 50 C.F.R. §424.18(c).

84 50 C.F.R. §424.02(b).

85 FWS, “ Candidate Species: Section 4 of the Endangered Species Act ,” October 2017. Hereinafter cited as FWS,

“Candidate Species.”

86 For a library of policies concerning candidate conservation, see FWS, “Endangered Species Act Document Library,”

at https://www.fws.gov/endangered/esa-library/index.html#cc_policy.

See CRS Report R44592, Sage-Grouse Conservation: Background and Issues, by M. Lynne Corn, Katie Hoover, and

Carol Hardy Vincent , for an example of the use of candidate conservation agreement s and candidate conservation

agreements with assurances in the conservation of a species.

88 FWS, “ Candidate Species.”

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The Secretary must monitor the status of a candidate species and, if any emergency poses a

significant risk to the well-being of the species, promptly list it. 89 Some steps in the normal listing

process may be skipped for these emergency listings.

Section 4(d) Rules

Section 4(d) allows the Secretary to extend certain protections that apply to endangered species to

threatened species. The act protects endangered species by prohibiting certain acts that may affect

them (see “ESA Section 9: Prohibitions”). For example, no person may import, export, sell, or

take (e.g., harm, hunt, harass, kill) an endangered species. However, those protections are not

automatically extended to threatened species in statute. Instead, Section 4(d) of the ESA

authorizes the Secretary to promulgate special regulations “as he deems necessary and advisable”

to conserve threatened species.90 Rules issued pursuant to this authority are known as 4(d) rules

or, alternatively, as special rules or species-specific rules. In a 4(d) rule, the Secretary may

prohibit nearly any act on a threatened species prohibited by ESA Section 9(a)(1) or (a)(2) for an

endangered species. Accordingly, protections for a particular threatened species can be tailored to

promote the conservation of the species and target specific threats to the species. Under the ESA,

the Services are not statutorily required to promulgate a 4(d) rule for every threatened species.

Historically, the two Services have taken different approaches to extending prohibitions to

threatened species. In 1975, FWS promulgated a regulation known as the blanket 4(d) rule, which

extended nearly all of the prohibitions provided for wildlife species listed as endangered to

wildlife species listed as threatened, unless the Service promulgated a species-specific 4(d) rule; a

similar rule for plants was issued in 1977. 91 These blanket 4(d) rules historically provided de

facto protections to FWS-listed threatened species, unless a species-specific 4(d) rule superseded

the blanket rule for that species. NMFS never established a blanket 4(d) rule and has extended

prohibitions to threatened species on a case-by-case basis through species-specific 4(d) rules.

Without the blanket 4(d) rule, there are no de facto protections for NMFS-listed threatened

species without species-specific 4(d) rules.

In August 2019, FWS modified its regulations to no longer employ the blanket 4(d) rule for

species listed as threatened after the revised regulation became effective on September 26, 2019. 92

Beginning September 27, 2019, species newly listed or reclassified as threatened were no longer

protected under the blanket 4(d) rule and did not have any de facto protections in the absence of a

species-specific 4(d) rule. Instead, these species had protective regulations only if FWS

promulgated a species-specific 4(d) rule, similar to how NMFS regulates threatened species. This

provision is not retroactive, so the blanket 4(d) rule continues to apply to species listed or

ESA §4(b)(3)(C)(iii), 16 U.S.C. §1533(b)(3)(C)(iii). T he Services determine what constitutes an emergency on a

case-by-case basis. For example, FWS issued an emergency rule to list the Columbia Basin distinct population segment

of the pygmy rabbit (Brachylagus idahoensis) as endangered in 2001, stating as reasons for the emergency listing that

“the immediate concerns for the Columbia Basin pygmy rabbit are associated with the population’s extremely small

size, history of fragmentation and extirpation, and the recent, dramatic decline in its distribution and abundance.” 66

Federal Register 59734, 59745, November 30, 2001.

90 ESA §4(d), 16 U.S.C. §1533(d).

91 T he blanket 4(d) protections for wildlife were implemented pursuant to FWS, 40 Federal Register 44425, September

26, 1975, as amended at FWS, 43 Federal Register, 18181, April 28, 1978; FWS, 44 Federal Register 31580, May 31,

1979; FWS, 70 Federal Register 10503, March 4, 2005. T he blanket 4(d) protections for plants were implemented

pursuant to FWS, 42 Federal Register 32380, June 24, 1977, as amended at FWS, 50 Federal Register 39691,

September 30, 1985.

92 84 Federal Register 44753.

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reclassified as threatened on or before September 26, 2019, that were not the subject of a speciesspecific rule. However, FWS may supersede existing blanket 4(d) rule protections by

promulgating a species-specific 4(d) rule for a species listed before the regulation became

effective. FWS’s rationale for changing its approach is that eliminating the blanket 4(d) rule more

closely aligns FWS policy with that of NMFS and that species-specific 4(d) rules incentivize

conservation, reduce the need for permitting for certain actions, and streamline Section 7

consultation under ESA. 93

FWS states that while it expects to promulgate a 4(d) rule concurrently with listing or

reclassifying a species as threatened, it did not find it necessary to require the simultaneous

promulgation of such a rule. 94 Some have raised concerns about the 2019 regulations by arguing

that if 4(d) rules are not issued for threatened species in a timely manner or at all, the species

could be negatively affected. Others contend the effect of this rule change on species depends on

how often FWS issues 4(d) rules and how soon after listing these rules are issued. 95 Under the

ESA, there is no timeline or deadline for issuing a 4(d) rule.

Experimental Populations

In 1982, Congress added experimental populations to the ESA to allow the Services to release or

introduce individuals of a species listed as threatened or endangered outside of the species’

current range. 96 An experimental population consists of the population introduced to an area, as

well as any offspring arising solely from that population. As of October 2020, 147 experimental

populations had been designated and released by the Services under the ESA since 1982.

To qualify as an experimental population, a population must meet two criteria:

1. The Services must have authorized the release of the population.

2. The population must be wholly separate geographically from other populations of

that species. 97

Congress required the geographic separation so the introduced experimental population could be

distinguished from the natural population of the species and the natural population could be

protected from the introduced population. 98 FWS has interpreted the requirement that the

populations be “wholly geographically separate” to apply to populations of the species rather than

to individuals. For example, FWS used this interpretation when it authorized introducing

experimental populations of the gray wolf into Montana, Wyoming, and Idaho; this interpretation

allowed the agency to reintroduce the gray wolf into parts of these three states even as FWS

93 84 Federal Register 44754-44755.

94 84 Federal Register 44754-44755.

Environmental Policy Innovation Center, Guide to the Revised Endangered Species Regulations, at 2019, at

http://policyinnovation.org/wp-content/uploads/2020/01/ESA-final-rules-analysis.pdf.

96 P.L. 97-304 §6(6), 96 Stat. 1424; ESA §10(j), 16 U.S.C. §1539(j). Experimental population designations are

sometimes referred to as Section 10(j) rules.

Plants are eligible for reintroduction as experimental populations, but to date no plants have been designated as such.

98 “Joint Explanatory Statement of the Committee of Conference,” Conference Report on H.R. 6133, Congressional

Record, daily edition, September 17, 1982, pp. 24157 -24158.

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acknowledged that lone wolves might disperse to the area from a population in northern

Montana. 99 When this rule was challenged, a court upheld FWS’s interpretation. 100

The Secretary determines whether each experimental population is essential or nonessential to the

survival of the species; this determination in turn affects the way the experimental population is

treated. An essential experimental population is one whose loss likely would result in appreciably

reducing the likelihood of the survival of the species in the wild. All other populations are

nonessential experimental populations. As of this report’s publication, no experimental

populations have been designated as essential.

Because the ESA’s provisions apply somewhat differently to experimental populations than to

listed populations, the authority to release experimental populations gave the Services an

opportunity to release a population of a listed species with potentially fewer restrictions on

federal and private actions in the area. 101 For example, regardless of whether the species is listed

as threatened or endangered, all essential experimental populations are regulated as threatened

species. As with threatened species, acts with respect to an essential experimental population are

prohibited only to the extent the Secretary orders in a species-specific 4(d) rule. 102

For the purpose of requirements under Section 7 of the ESA (see “Section 7 Consultation Process

and Biological Opinions,” below), nonessential experimental populations are treated in the same

manner as candidate species, except when the experimental population occurs on lands of the

National Wildlife Refuge System or the National Park System. 103 As such, federal agencies must

confer with the Secretary regarding any actions that might jeopardize the continued existence of

the species, but the Services need not engage in full Section 7 consultation or refrain from

irreversibly or irretrievably committing agency resources to the action unless the action takes

place on national wildlife refuges or in national parks. In addition, the Services cannot designate

critical habitat for nonessential experimental populations.

Critical Habitat

One of the ESA’s purposes is to conserve the “ecosystems upon which endangered species and

threatened species depend,” which includes their habitat. 104 The loss or alteration of habitat is a

factor for listing species. 105 The ESA directs the Services to designate critical habitat for listed

species and requires that federal agencies not destroy or adversely modify that habitat through

their actions. 106

99 59 Federal Register 60253-60254; 59 Federal Register 60267-60269.

100 Wyo. Farm Bureau Fed’n v. Babbitt, 199 F.3d 1224, 1234, 1237 (10 th Cir. 2000).

101

T hough the Services had preexisting authority to release listed species prior to the inclusion of the authority related

to experimental populations, a court, reviewing the statute’s legislative history, concluded that Congress added this

section to address the Services’ frustration with political opposition to such reintroduction efforts borne from “fears

experimental populations would halt development projects.” Wyo. Farm Bureau Fed’n, 199 F.3d at 1231-32 (citing

H.R. Rep. No. 97-567, at 8 (1982)).

102

T he blanket 4(d) rule did not apply to experimental populations. See 83 Federal Register 35176.

103 ESA §10(j)(C)(i), 16 U.S.C. §1539(j)(C)(i).

104 ESA §2(c), 16 U.S.C. §1531(c).

D. M. Evans et al., “Species Recovery in the United States: Increasing the Effectiveness of the Endangered Species

Act,” Issues in Ecology, vol. 20 (Winter 2016). Hereinafter cited as Evans, “Species Recovery.”

105

106 ESA §4(a)(3)(A), 16 U.S.C. §1533(a)(3)(A) and ESA §7(a)(2), 16 U.S.C. §1536(a)(2).

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The ESA defines critical habitat to include geographic areas occupied or not occupied by the

species at the time of listing. 107 Areas occupied by the species at the time of listing must have

physical and biological features that (1) are essential to the conservation of a species and (2) may

require certain management considerations or protection. 108 Areas not occupied by the species at

the time of listing may be designated as critical habitat if the Secretary determines that such

additional areas are “essential for the conservation of the species.”109 Of particular relevance to

unoccupied areas, the Supreme Court concluded in Weyerhaeuser Co. v. U.S. Fish and Wildlife

Service that an area must be habitat for a species in order to be designated as critical habitat. 110 In

response to the Court’s decision, the Services issued a final rule in December 2020 defining

habitat in the ESA implementing regulations. 111 Furthermore, pursuant to regulations

promulgated in an August 2019 final rule, the Services may designate unoccupied areas as critical

habitat only if they determine that occupied areas alone are inadequate to conserve the species

and that the unoccupied areas contain one or more physical or biological features essential to the

species’ conservation. 112 In general, critical habitat cannot include the entire geographical area

that a listed species could occupy, except in circumstances determined by the Secretary. 113

The Secretary must designate critical habitat concurrently with listing a species “to the maximum

extent prudent and determinable.”114 If the species’ critical habitat is not determinable at the time

of listing, the Secretary may postpone designation for up to one year; after that year, the Secretary

must designate critical habitat to the maximum extent prudent based on the available

information. 115 The Services’ regulations identify certain circumstances in which the Secretary

may determine that designating critical habitat is not “prudent,” including the following:



The designation of critical habitat for a listed species would result in a greater

risk of the species being threatened by takings (e.g., if critical habitat is known,

then poachers would have a better idea of where the species resides).



The present or threatened destruction or alteration of habitat is not a threat to the

species, or threats to the species stem solely from causes that cannot be addressed

through habitat management under Section 7 consultation.

Areas within U.S. jurisdiction provide negligible conservation value for the

species because it resides primarily outside of U.S. jurisdiction.

No areas meet the definition of critical habitat.



The Secretary otherwise determines the designation of critical habitat would not

be prudent based on the best scientific data available. 116

107 ESA §3(5), 16 U.S.C. §1532(5).

108 ESA §3(5), 16 U.S.C. §1532(5).

109 ESA §3(5), 16 U.S.C. §1532(5).

110 139 S. Ct. 361, 368 (2018).

111 FWS and NOAA, “Regulations for Listing Endangered and T hreatened Species and Designating Critical Habitat,”

85 Federal Register 81411, December 16, 2020. FWS issued a final rule in December 2020 that also responded, in part,

to the Weyerhauser opinion by clarifying the process by which FWS would exclude areas from being designated as

critical habitat. FWS, “Regulations for Designating Critical Habitat,” 85 Federal Register 82376, December 18, 2020.

50 C.F.R. §424.12. FWS and NOAA, “Endangered and T hreatened Wildlife and Plants; Regulations for Listing

Species and Designating Critical Habitat,” 84 Federal Register 45020, August 27, 2019.

112

113

ESA §3(5)(C), 16 U.S.C. §1532(5)(C).

114 ESA §4(a)(3)(A), 16 U.S.C. §1533(a)(3)(A).

115 ESA §4(b)(6)(C), 16 U.S.C. §1533(b)(6)(C).

116 50 C.F.R. §424.12.

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As of October 2020, the Services have designated critical habitat for approximately 1,000 listed

species, or roughly 60% of the 1,666 listed domestic animal and plant species. 117 Critical habitat

size varies considerably by species. For example, FWS designated more than 9 million acres of

critical habitat for the Indiana bat and the Mexican spotted owl, whereas FWS designated 21

acres of critical habitat for the Leon Springs pupfish. 118

Designation of Critical Habitat

The Secretary designates critical habitat based on the best scientific data available after

considering potential economic, national security, and other relevant impacts that may arise from

designating areas as critical habitat. 119 Unlike listing decisions where the Secretary cannot

consider economic factors, the Secretary must consider economic factors when designating

critical habitat. The Secretary may exclude any area from designation as critical habitat if the

benefits of excluding the area outweigh the benefits of designating it as critical habitat, unless the

best available scientific and commercial data indicate that failing to designate such area as critical

habitat could result in the species’ extinction. 120

Revisions to Critical Habitat Regulations in 2019 Rules

In August 2019, the Services promulgated a final rule—effective September 26, 2019—addressing the designation

of critical habitat. The Services amended the list of circumstances under which the Services might find it prudent

not to designate critical habitat. The revised regulations replaced the circumstance that designating critical habitat

would not benefit the species with four other circumstances. For example, the Secretary could determine that

designating critical habitat is not prudent because no areas meet the definition of critical habitat or there are no

habitat-based threats to the species (e.g., the conservation of a species threatened solely by illegal trade may not

effectively be addressed through habitat management).

The final rule also clarified when the Secretary may designate unoccupied areas as critical habitat. Under the ESA,

unoccupied areas must be essential to the species’ conservation to be critical habitat. The final rule specified that

for unoccupied areas to be deemed essential, the Secretary must find that the species’ occupied habitat at the time

of listing is inadequate to ensure the species’ conservation. The Secretary also must determine that it is reasonably

certain the unoccupied area will contribute to the species’ conservation and that the unoccupied area contains at

least one physical or biological feature essential to the species’ conservation, as defined in the regulation.

Source: FWS and National Oceanic and Atmospheric Association (NOAA), “Endangered and Threatened

Wildlife and Plants: Regulations for Listing Species and Designating Critical Habitat,” 84 Federal Register 4502045053, August 27, 2019; FWS, “Endangered and Threatened Wildlife and Plants: Regulations for Designating

Critical Habitat,” 85 Federal Register 55398-55407, September 8, 2020.

The Secretary can revise critical habitat designations independently at any time or pursuant to a

petition. For petition-initiated requests, the ESA contains timelines for addressing revisions to

critical habitat. As with petitions for listing or delisting, the Secretary, to the maximum extent

practicable, has 90 days from receiving a petition to revise critical habitat to determine whether

the petition contains sufficient scientific information to show that a revision may be warranted.

T he information at FWS, “ECOS – T hreatened & Endangered Species Active Critical Habitat Report ,” at

https://ecos.fws.gov/ecp/report/table/critical-habitat.html, is updated daily. For marine species, see ESA T hreatened and

Endangered Species at https://www.fisheries.noaa.gov/species-directory/threatened-endangered.

118 FWS, “ECOS – T hreatened & Endangered Species Active Critical Habitat Report ,” at https://ecos.fws.gov/ecp/

report/table/critical-habitat.html.

117

119 ESA §4(b)(2), 16 U.S.C. §1533(b)(2).

120 ESA §4(b)(2), 16 U.S.C. §1533(b)(2).

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The Secretary has 12 months from receiving the petition to make a final determination on how to

proceed with the requested revision and publish the finding in the Federal Register. 121

The ESA exempts Department of Defense land from being designated as critical habitat in certain

situations. The National Defense Authorization Act for Fiscal Year 2004 (P.L. 108-136) amended

the ESA to specify that the Secretary shall not designate critical habitat on lands controlled by the

Department of Defense if those lands are subject to an Integrated Natural Resource Management

Plan (INRMP) under the Sikes Act (16 U.S.C. §670a). 122 For the provision to apply, the Secretary

must determine the INRMP provides “a benefit” to the lands that otherwise might have been

designated as critical habitat. 123 The ESA also directs the Secretary to consider national security

when designating critical habitat. According to legislative history, Congress added these

provisions in response to assertions that designating critical habitat on some military lands was

interfering with military training and readiness activities. 124

121

ESA §4(b)(3)(D), 16 U.S.C. §1533(b)(3)(D).

ESA §4(a)(3)(B), 16 U.S.C. §1533(a)(3)(B). An Integrated Natural Resource Management Plan is a planning

document that provides Department of Defense installations guidance to implement landscape -level management

actions to conserve natural resources in collaboration with various stakeholders. T he authority for conducting these

plans is under t he Sikes Act (16 U.S.C. §670(a)-670(f)).

122

123 ESA §4(a)(3)(B)(1), 16 U.S.C. §1533(a)(3)(B)(1). T he military remains subject to the ESA’s other provisions,

including those on consultation and taking.

124 For example, see U.S. Congress, House Committee of the Wh ole House on the State of the Union, National Defense

Authorization Act for Fiscal Year 2003, Conference Report to Accompany H.R. 4546, 107th Cong., 2 nd sess., November

12, 2002, H.Rept. 107-772 (Washington: GPO, 2002), p. H8452.

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Conservation Value of Designating Critical Habitat

There is an ongoing debate as to the conservation value of designating critical habitat under the ESA. Some

stakeholders contend that critical habitat offers little protection for a species beyond the other ESA protections

available to listed species (e.g., prohibited acts under Section 9 and the consultation requirements under Section

7). Thus, in their view, the expense of designation, which may arise from complying with consultation under ESA

Section 7 (see “Section 7 Consultation Process and Biological Opinions” in this report) and the perception of a

small margin of additional conservation benefit make critical habitat requirements a poor use of budgetary

resources. In summary, some stakeholders view critical habitat as a regulatory burden of the ESA rather than a

conservation benefit that supplements the ESA’s prohibition on taking certain listed species.

In contrast, some observers argue that critical habitat designation provides an added conservation benefit,

particularly when it includes areas not currently occupied by the species. They assert the following potential

benefits of designating critical habitat:



Designation of critical habitat may provide additional protection for listed species in the context of federal

actions. Federal agencies must consider whether their actions are likely to destroy or adversely modify

critical habitat under the Section 7 consultation provisions. If critical habitat were not designated, Section 7

consultations would be limited to whether actions jeopardize a species’ continued existence.



Designation of critical habitat requires the Secretary to consider what habitat is essential for conservation of

the species and the economic and other effects of designating critical habitat. Analyzing the economic effects

of designation might inform landowners on how to manage their lands to support the species and reduce

economic costs.



Critical habitat might inform landowners where listed species may be located, allowing landowners to avoid

taking such species and incurring the associated penalties.



Critical habitat designation might encourage landowners to modify land uses that go beyond statutory

requirements.



The process of designating critical habitat might yield scientific information about the species that benefits

habitat conservation and recovery planning and provides information for permitting incidental take.



Critical habitats may serve as connecting corridors between populations, areas for existing populations to

expand into, or areas in which new populations may be reintroduced. In addition, unoccupied habitat might

be important for species that migrate or are forced from their current habitat due to environmental changes,

such as changes to climate (e.g., increased drought) or the ecosystems in which the species resides (e.g., sea

level rise and saltwater intrusion).

Sources: R. J. Scarpello, “Statutory Redundancy: Why Congress Should Overhaul the Endangered Species Act to

Exclude Critical Habitat Designation,” Boston College Environmental Affairs Law Review, vol. 30, no. 399 (2003), pp.

399-431; A. N. Hagen and K. E. Hodges, “Resolving Critical Habitat Designation Failures: Reconciling Law, Policy,

and Biology,” Conservation Biology, March 27, 2006, pp. 356-366; K. Suckling and M. Taylor, “Critical Habitat and

Recovery: A Legal, Case Study, and Quantitative Review,” in D. D. Goble, J. M. Scott, and F. W. Davis, eds., The

Endangered Species Act at 30: Renewing the Conservation Commitment (Washington, DC: Island Press), 2005.

Recovery of Listed Species

To guide recovery efforts, the ESA requires the Secretary to develop recovery plans for the

conservation and survival of listed species, unless the Secretary finds that developing a recovery

plan would not benefit the species. 125 Recovery plans aim to identify the listed species’ condition

and threats the species faces (i.e., conduct a species status assessment) and to provide a vision for

and pathway toward the species’ recovery (i.e., recovery implementation strategy). The Services’

recovery planning guidance notes that “recovery recommendations are based on resolving the

threats to the species and ensuring self-sustaining populations in the wild.”126

125

ESA §4(f), 16 U.S.C. §1533(f).

126

NMFS, Interim Endangered and Threatened Species Recovery Planning Guidance Version 1.4 , July 2018.

Hereinafter cited as NMFS, Recovery Planning Guidance.

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A 1988 ESA amendment added requirements for recovery plan contents. 127 The law specified that

each plan is to include three elements, to the maximum extent practicable:

1. A description of management actions needed to accomplish a plan’s goal for the

conservation and survival of the species

2. Objective, measurable criteria that, when met, would lead to downlisting or

delisting the species

3. The estimated time and cost of carrying out measures to achieve the plan’s

goal128

Overall, the Services have stated that recovery plans are guiding documents that are not binding

on federal agencies or other entities to implement. 129 The Services use a species status assessment

(SSA), often created during the listing process, to inform the species recovery plan. 130 The

Services use the best available science about a species to evaluate the species’ present and

potential future threats. An SSA assesses a species’ ability to maintain self-sustaining populations

over time. 131 The Services use the three principles of conservation biology to conduct this

assessment: resilience, redundancy, and representation. 132 FWS explains the principles as follows:

Representation describes the ability of a species to adapt to changing environmental

conditions, which is related to distribution within the species’ ecological settings.

Resiliency describes the ability of the species to withstand stochastic disturbance events,

which is associated with population size, growth rate, and habitat quality. Redundancy

describes the ability of a species to withstand catastrophic events, which is related to the

number, distribution, and resilience of populations. Together, the 3Rs, and their core

autecological parameters of abundance, distribution and diversity, comprise the key

characteristics that contribute to a species’ ability to sustain populations in the wild over

time. When combined across populations, they measure the health of the species as a

whole.133

The ESA requires the Services to provide the public with an opportunity to review and comment

on each new or revised recovery plan before final approval. Further, FWS has stated that its

policy is to solicit scientific peer review of recovery plans from three independent reviewers. 134

The Services’ guidance provides a time frame for completing recovery plans. (See Table 1.)

127 P.L. 100-478.

128

ESA §4(f)(1)(B), 16 U.S.C. §1533(f)(1)(B).

129 NOAA, Recovery of Species Under the Endangered Species Act, July 10, 2020, at https://www.fisheries.noaa.gov/

national/endangered-species-conservation/recovery-species-under-endangered-species-act#:~:text=

Are%20Recovery%20Plans%3F,A%20recovery%20plan%20serves%20as%20a%20road%20map%20for%20species,support%20recovery%20of%20a

%20species.

130

Most listing, reclassification, and delisting decisions are accompanied by an SSA. T he SSA ideally is created during

the initial listing stage but can be initiated at any time, according to FWS. FWS, Species Status Assessment

Framework: An Integrated Analytical Framework for Conservation, Version 3.4 , August 2016, at https://www.fws.gov/

endangered/improving_esa/pdf/SSA%20Framework%20v3.4-8_10_2016.pdf. Hereinafter cited as FWS, Species

Assessment Framework. NOAA conducts population viability analyses to assess the population status of the species

that it covers.

131 FWS, “ Species Status Assessment Framework: An Integrated Framework for Conservation,” August 2016, at

https://www.fws.gov/endangered/improving_esa/pdf/SSA_Fact_Sheet -August_2016.pdf.

132

FWS, Species Assessment Framework.

133 FWS, Species Assessment Framework.

134 FWS, Delisting a Species: Section 4 of the Endangered Species Act, April 2011, at https://www.fws.gov/

endangered/esa-library/pdf/delisting.pdf. Hereinafter cited as FWS, Delisting a Species. T he ESA does not require this

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Table 1. Time Frame for Recovery Plan Development for FWS and NMFS

(policy guidance; not mandated in law)

Time Frame

Action

60 days from date of listing

Recovery outline completed and submitted

90 days from date of listing

Recovery outline approved

18 months from date of listing

Draft recovery plan completed, published in the Federal

review

30 months from date of listing

Final recovery plan completed and approved

Sources: NMFS, Interim Endangered and Threatened Species Recovery Planning Guidance, Version 1.4, last updated

July 2018. (FWS has adopted these guidelines.)

The Services must provide a report to Congress on the status of recovery plan development and

implementation for all listed species every two years.135 As of October 2020, there were more

than 600 draft and final recovery plans for 1,666 species listed in the United States. 136 According

to one study, as of January 2018, almost one-third of species that had been listed for more than

2½ years did not have a recovery plan. 137 The study states that the main reason for not completing

recovery plans is inadequate funding for recovery planning. 138

Under some circumstances, the Services may decide not to prepare a recovery plan for a listed

species. For example, the Services may decide not to prepare recovery plans for species that the

Services determine will not receive a conservation benefit from the recovery plan; that is

expected to be delisted due to extinction or an error in listing; or whose range is entirely in a

foreign country (i.e., foreign species). 139

The creation and implementation of recovery plans for listed species have generated discussion

over the plans’ usefulness for identifying when a species is recovered and can be delisted. 140

Although the ESA requires recovery plans to include objective and measurable criteria for

delisting to the maximum extent practicable, the act does not require the Services to base delisting

decisions on meeting those recovery plan criteria—delisting decisions are based on a status

review pursuant to the ESA definitions and factors. 141 Some stakeholders suggest that recovery

plans create false expectations and inconsistencies in delisting decisions. 142 In 2019, the

Department of the Interior (DOI) responded to this concern by setting an agency goal to provide

clarity as to when a listed species can be downlisted or delisted. 143 To facilitate attaining this goal,

form of review.

135 ESA §4(f)(3), 16 U.S.C. §1533(f)(3). See, for example, Conservation Cong. v. Finley, 774 F.3d 611, 620 (9 th Cir.

2014); Friends of Blackwater v. Salazar, 691 F.3d 428, 429 (D.C. Cir. 2012); Fund for Animals v. Rice, 85 F.3d 535,

547 (11 th Cir. 1996).

136 T he information at FWS, “ Environmental Conservation Online System (ECOS) – Listed Species Summary,” at

https://ecos.fws.gov/ecp/report/boxscore, is updated daily. Some recovery plans cover more than one listed species.

137 Jacob W. Malcom and Li Ya-Wei, “Missing, Delayed, and Old: T he Status of ESA Recovery Plans,” Conservation

Letters, vol. 11, no. 12601 (2018), pp. 1-9. Hereinafter cited as Malcom and Li, “Missing, Delayed, and Old.”

138

Malcom and Li, “Missing, Delayed, and Old.”

139 NMFS, Recovery Planning Guidance, p. 2.2.1.

140 Evans, “Species Recovery.”

141

50 C.F.R. §424.11(e). For example, see Defenders of Wildlife v. Hall, 565 F. Supp. 2 d 1160, 1170 (D. Mont. 2008).

142 50 C.F.R. §424.11(e).

143 DOI, Ensure Clear, Quantitative Criteria for Threatened and Endangered Species Recovery Plans; DOI, Agency

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DOI stated it would require 100% of FWS-promulgated recovery plans to include quantitative

criteria that specify when a species has recovered. 144

Delisting, Uplisting, and Downlisting

The processes for delisting, uplisting, or downlisting a listed species are generally the same as the

processes for listing species and use the same criteria (i.e., the definitions of endangered and

threatened species and the five listing factors under Section 4). 145 As with listing decisions, the

Services must make the determination to delist, uplist, or downlist a species “solely on the basis

of the best scientific and commercial data available,” without considering possible economic or

other effects. 146 The Services’ regulations state they will delist a species if they find the species is

extinct, does not meet the definition of an endangered or threatened species, or does not meet the

definition of a species (e.g., taxonomic revision). 147 The Secretary may initiate delisting or

reclassifying a species independently or may act on a petition for any change in a species’ listing

status.

The ESA mandates the Secretary review the status of each listed species at least once every five

years to determine whether the species should be delisted, uplisted, or downlisted. 148 For species

with recovery plans, this five-year review may include assessing whether the species has met the

plan’s recovery goals. However, the Services are not bound to delist or downlist a species that

attains its recovery goals, nor are they prevented from downlisting or delisting a species that has

not met its recovery goals. 149

After a species is delisted, the ESA requires the Services, in cooperation with the states in which

the species is found, to monitor the species’ status for at least five years. 150 To implement this

requirement, the Services prepare a delisting monitoring plan, which is peer reviewed and subject

to public comment. 151 Monitoring allows the Services to assess whether the species remains

recovered (i.e., not endangered or threatened) without the ESA’s protection. The ESA also

requires the Secretary to exercise emergency authority to relist a delisted species when necessary

“to prevent a significant risk to the wellbeing” of the species. 152 As of October 2020, no species

had been relisted on an emergency basis under this authority.

Priority Goal Action Plan, 2019, at https://assets.performance.gov/APG/Interior/

FY2019_June_Interior_Ensure_Clear_Quantitative_Criteria_for_Threatened_and_Endangered_Species_Recovery_Pla

ns.pdf.

144 DOI, Ensure Clear, Quantitative Criteria for Threatened and Endangered Species Recovery Plans.

145

ESA §4(c), 16 U.S.C. §1533(c).

146 ESA §4(b)(1)(A), 16 U.S.C. §1533(b)(1)(A); 50 C.F.R. §424.11(b).

147 50 C.F.R. §424.11(e).

148 ESA §4(c), 16 U.S.C. §1533(c) and 50 C.F.R. §424.21.

149 See, for example, Friends of Blackwater v. Salazar, 691 F.3d 428, 436 (D.C. Cir. 2012).

150 ESA §4(g), 16 U.S.C. §1533(g).

151

FWS, Delisting a Species, and NOAA, Delisting Species Under the Endangered Species Act, December 27, 2019, at

https://www.fisheries.noaa.gov/national/endangered-species-conservation/delisting-species-under-endangered-speciesact.

152 ESA §4(b)(7), 16 U.S.C. §1533(b)(7).

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ESA Section 5: Land Acquisition

Section 5 of the ESA authorizes the acquisition of land to conserve (i.e., recover) endangered and

threatened species. Approximately half of the species listed under the ESA have at least 80% of

their habitat on private lands, according to FWS. 153 The act directs the Secretary of the Interior

and the Secretary of Agriculture (through the National Forest System) to establish a program to

conserve fish, wildlife, and plants, including species listed under the ESA. 154 The Secretaries may

use several existing authorities, listed in the act, to achieve these purposes. The ESA also

authorizes the Secretaries to acquire lands and waters through purchase, donations, or other

means. Money from the Land and Water Conservation Fund (LWCF) may be appropriated for

these acquisitions. 155 The LWCF is a federal fund derived primarily from receipts from offshore

oil and gas leases; it is used for land acquisitions by the four agencies charged with managing

most federal lands, among other things. 156

FWS reports expenditures for listed species annually and includes expenditures for land

acquisition. The last annual expenditure report was published for FY2017;157 this report lists

federal agencies’ land acquisition expenditures that are “reasonably identifiable to specific

individual species.” In FY2017, federal agencies spent approximately $51.7 million and states

spent approximately $5.0 million to acquire land for listed species and potentially other purposes.

Three federal agencies spent the majority of funds to acquire land to conserve listed species: FWS

spent approximately $21.1 million; the U.S. Department of Agriculture spent $19.9 million; and

the Bureau of Reclamation spent $9.1 million. 158 The greatest amount of funds spent to acquire

lands for a single species in FY2017 was approximately $11.0 million for the wood stork

(Mycteria americana).

ESA Section 6: Cooperation with States

Section 6 of the ESA requires the Secretary to cooperate with the states to the maximum extent

practicable in conserving federally protected species. 159 FWS and courts have recognized the

states’ “key role” in regulating wildlife and catalyzing conservation efforts by landowners and

communities on private land. 160 Section 6 enables the Secretary to facilitate state conservation

programs and to direct federal funding toward such efforts. 161

153 FWS, Our Endangered Species Program and How It Works with Landowners, July 2009, at https://www.fws.gov/

endangered/esa-library/pdf/landowners.pdf.

154 ESA §5(a), 16 U.S.C. §1534(a).

155 ESA §5(b), 16 U.S.C. §1534(b).

156 T he four agencies are FWS, Bureau of Land Management, and National Park Service, all in DOI, and the Forest

Service in the Department of Agriculture. For more on the fund, see CRS Report RL33531, Land and Water

Conservation Fund: Overview, Funding History, and Issues, by Carol Hardy Vincent .

157 FWS, Federal and State Threatened and Endangered Species Expenditures FY2017 , 2018, at https://www.fws.gov/

endangered/esa-library/pdf/2017-Expenditures-Report.pdf. Hereinafter cited as FWS, Federal and State Expenditures.

158 FWS, Federal and State Expenditures.

159 ESA §6(a), 16 U.S.C. §1535(a).

FWS, “Grants: Overview,” updated January 30, 2020, at https://www.fws.gov/endangered/grants/; Gibbs v. Babbitt,

214 F.3d 483, 499 (4 th Cir. 2000).

160

161 ESA §6, 16 U.S.C. §1535.

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The ESA authorizes the Secretary to enter into agreements with states to assist with state

conservation efforts. 162 The Secretary may enter into agreements with states, referred to as

management agreements, to administer and manage any area created to conserve listed species. In

addition, the Secretary is required to enter into a cooperative agreement with any state that

establishes and maintains an “adequate and active” state program to conserve listed species that

the Secretary determines meets certain statutory criteria. 163

Management Agreements

The Secretary may enter into management agreements with states for the administration and

management of areas established for the conservation of species listed under the ESA. 164

Cooperative Agreements

A cooperative agreement between the Secretary and a state facilitates the state establishing and

maintaining its own program to conserve species listed under the ESA. To initiate the process, the

state submits a plan for the program to the Secretary. To qualify for a cooperative agreement, the

state program must include the following elements:165



The state agency that is carrying out the program (e.g., a state’s fish and wildlife

agency) has the authority to conserve resident fish and wildlife species that are

listed under the federal or state endangered species act.

The state has established acceptable conservation programs, consistent with the

ESA, for conserving all resident listed species that the Secretary has deemed

endangered or threatened under the ESA.

The state agency is authorized to investigate the status and requirements for

resident species’ survival.

The state agency is authorized to establish programs to conserve resident listed

species, including through land acquisition.

The state provides for public participation in designating resident species as

endangered or threatened.

Similar requirements apply to cooperative agreements with states that address the conservation of

plant species. 166

The ESA requires states to enter into such cooperative agreements to be eligible for federal

funding. The Secretary is authorized to provide funds to any state that has entered into a

cooperative agreement to assist with implementing the state’s program to conserve species listed

under the ESA or with monitoring candidate and delisted species, including land acquisition and

planning assistance. 167 The states generally must provide at least 25% of the program costs

162 ESA §6, 16 U.S.C. §1535.

163

ESA §6(c)(1), 16 U.S.C. §1535(c)(1).

164 ESA §6(b), 16 U.S.C. §1535(b).

165 ESA §6(c)(1), 16 U.S.C. §1535(c)(1). T he Secretary has 120 days to after receiving a proposed state program to

determine whether the program is in accordance with the ESA.

166 ESA §6(c)(2), 16 U.S.C. §1535(c)(2).

167 ESA §6(d), 16 U.S.C. §1535(d).

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through matching funds (i.e., the federal component cannot exceed 75% of the cost), though the

federal component may be greater for certain multistate conservation agreements.168

The 1988 ESA amendments created a fund—known as the Cooperative Endangered Species

Conservation Fund (CESCF)—to provide funding for state grants, including land acquisition and

planning assistance. 169 Although the amount of money deposited into the fund is authorized

according to requirements set in statute, money from the fund can be disbursed only through

discretionary appropriations. 170 Congress can appropriate funds from the CESCF to address state

programs under cooperative agreements. The ESA requires that certain mandatory funding be

deposited into the CESCF; the amounts deposited into the CESCF are equal to (1) 5% of the total

amounts deposited in the Wildlife and Sport Fish Restoration accounts each fiscal year and (2) the

amount by which the balance of fines, penalties, and forfeited property for violations of the ESA

and the Lacey Act (P.L. 100-478) exceeds $500,000.171

Outside of cooperative and management agreements, cooperation and consultation between the

federal and state governments occurs in several other instances. For example, the federal

government is required to consult with state governments before acquiring any land or water for

the conservation of listed species. 172 Table 2 shows other instances of federal-state cooperation

and consultation under the ESA.

Table 2. Selected Examples of Federal-State Cooperation Under the ESA

ESA Process

Listing and Critical

Habitat

Description of Federal Cooperation with States

Works with state experts to develop a scientific foundation for listing, delisting, and

reclassifying decisions and critical habitat designations

Provides notice to state agencies of any proposed listing or critical habitat rule in

accordance with the ESA and works with states on future listing and critical habitat plans

Candidate Species

Uses states’ expertise and solicits their information to determine which species should

be included on the list of candidate species

Works with states on conservation planning to reduce threats to candidate and listed

species

Works with states to implement candidate conservation agreements with assurances to

provide nonfederal landowners incentives to conserve candidate species

Consultation

Informs state agencies of federal agency actions that are likely to adversely affect listed

species and critical habitat, and collects information from states to help in the

consultation process required under Section 7 of the ESA

Requests updated information, including scientific and commercial data, from the state

on the species or habitat that could help in preparing a final biological opinion

Habitat

Conservation

Planning

168

Uses the states’ expertise in all aspects of the habitat conservation planning process for

species under states’ jurisdiction

Collaborates with states to work efficiently on permitting activities related to listed

species

ESA §6(d), 16 U.S.C. §1535(d)(2)(i).

169 P.L. 100-478.

170 ESA §6(i), 16 U.S.C. §1535(i).

171 Per ESA §6(i), 16 U.S.C. §1535(i), an amount equal to 5% of the funds deposited into the Federal Aid to Wildlife

Restoration Fund (the program that administers this fund is also known as Pittman -Robertson; 16 U.S.C. §§669 et seq.)

and the Federal Aid to Sport Fish Restoration Fund (the program that administers this fund is also known as DingellJohnson; 16 U.S.C. §§777 et seq.) is deposited into the Cooperative Endangered Species Conservation Fund.

172 ESA §6(a), 16 U.S.C. §1535(a).

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ESA Process

Recovery

Description of Federal Cooperation with States

Uses the states’ expertise in all aspects of the recovery planning process for species

under states’ jurisdiction, including implementing recovery plans

Uses states’ expertise and authority in designing monitoring programs for species that

have been delisted

Works with states to design and encourage the use of safe harbor agreements to assist

in the recovery of listed species

(Safe harbor agreements are voluntary agreements between the Services and nonfederal

landowners that provide nonfederal landowners assurances the Services will not impose

restrictions on their land if a landowner conducts conservation actions that benefit listed

species or species that might be listed in the future)

Source: FWS and National Oceanic and Atmospheric Association (NOAA), “Revised Interagency Cooperative

Policy Regarding the Role of State Agencies in Endangered Species Act Activities,” 81 Federal Register 8663-8665,

February 22, 2016.

To allow for a continuing state role in endangered species conservation, the ESA’s preemption of

state law is limited. The ESA voids any state regulation that addresses the import or export of, or

interstate or foreign commerce in, listed species and either (1) permits actions the ESA prohibits

or (2) prohibits actions the ESA allows (e.g., in an exemption or permit). 173 The act otherwise

allows states to retain and enforce laws or regulations that aim to conserve listed species. Further,

any state law or regulation that addresses taking listed species may be more restrictive than ESA

and the accompanying regulations—but not less. 174

Most states have enacted laws aiming to protect endangered or threatened species. 175 Forty-four

states have statutes that allow the state government to identify species in danger of extinction and

provide some form of protection for these species.176 Of the other six states, Alabama, West

Virginia, and Wyoming do not have any statutes providing for identifying or conserving

173 ESA §6(f), 16 U.S.C. §1535(f).

174 ESA §6(f), 16 U.S.C. §1535(f).

175 State endangered species acts may include federally listed species and additional species not listed under the federal

ESA. T hree states have no provisions (Alabama, West Virginia, and Wyoming), and several states have varied

protections.

176 ALASKA STAT. §§16.20.180 – 16.20.270; ARIZ. REV. STAT. ANN . §§17-268, 17-296 – 17-298.01, 17-314; CAL . FISH

& GAME CODE §§1900 – 1913, 2050 – 2089.26; COLO . REV. STAT. §33-2-101 – 33-2-107; CONN . GEN . STAT. ANN .

§§26-303 – 26-316; DEL . CODE. ANN. tit. 7 §§601 – 605; FLA . STAT. §§379.2291, 379.411, 581.185; GA . CODE ANN .

§§27-3-130 – 27-3-133; HAW . REV. STAT. ANN . §§195d-1 – 195d-32; 520 I LL . COMP. STAT. ANN . 10/1 – 10/11; I ND.

CODE ANN . §§14-22-34-1 – 14-22-34-21; I OWA CODE ANN . §§481b.1 – 481b.10; KAN . STAT. ANN . §§32-957 – 32-962;

KY . REV. STAT. ANN . §§146.601 – 619, 150.183; LA . STAT. ANN . §§56:1901 – 56:1907; ME . STAT. tit. 12 §§6971–

6978, 12801–12810; MD . CODE ANN ., NAT. RES. §§10-2A-01 – 10-2A-09, 4-2A-01 – 4-2A-09; MASS. GEN . LAWS ANN.

ch. 131A §§1-7; MICH . COMP . LAWS ANN. §§324.36501 – 324.36507; MINN. STAT. §§84.0894 – 84.0895, 97A.501;

MISS. CODE ANN . §§49-5-101 – 49-5-119; MO. ANN. STAT. §252.240; MONT. CODE ANN. §§87-5-101 – 87-5-132; NEB.

REV. STAT. ANN . §§37-801 – 37-811; NEV. REV. STAT. ANN . §503.584 – 503.589; N.H. REV. STAT. ANN . §§212-A:1 –

212-A:15, 217-A:1 – 217-A:12; N.J. STAT. ANN . §§23:2A-1 – 23:2A-13, 13:1B-15.151 – 13:1B-15.158; N.M. STAT.

ANN . §§17-2-37 – 17-2-46, 75-6-1; N.Y. ENV’T CONSERV. LAW §§9-1503, 11-0535; N.C. GEN . STAT. ANN . §§106202.12 – 106-202.22, 113-331 – 113-350; N.D. CENT. CODE ANN . §§20.1-01-02, 20.1-02-05; OHIO REV. CODE ANN.

§§1518.01 – 1518.05, 1518.99, 1531.25 – 1531.26, 1531.99; OKLA. STAT. tit. 29 §§2-109, 2-135, 5-402, 5-412, 5-412.1,

7-502, 7-601 – 7-602; OR. REV. STAT. ANN . §§496.171 – 496.192, 498.026, 564.010 – 564.994; 30 PENN. STAT. & CONS.

STAT. ANN . §2305; 32 P ENN. STAT. & CONS. STAT. ANN . §5307; 34 P ENN. STAT. & CONS. STAT. ANN . §§102, 925, 2167,

2924; 20 R.I. GEN . LAWS ANN. §§20-37-1 – 20-37-5; S.C. CODE ANN. §§50-1-270, 50-15-10 – 50-15-90; S.D. CODIFIED

LAWS §§34A-8-1 34A-8-13; TENN. CODE ANN. §§70-8-101 – 70-8-112, 70-8-301 – 70-8-314; TEX. P ARKS & W ILD.

CODE ANN . §§68.001 – 68.021, 88.001 – 88.012; VT. STAT. ANN . tit. 10 §§4518, 5401 – 5410; VA . CODE ANN. §§3.21000 – 3.2-1011, 29.1-563 – 29.1-570; W ASH. REV. CODE ANN. §§77-08-010, 77-12-020, 77-15-120, 77-15-130, 77-15135, 77-15-420; W IS. STAT. ANN . §§29.604, 29.983, 169.01, 169.30.

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endangered or threatened species. Arkansas declares a public policy of “promot[ing] sound

management, conservation, and public awareness of Arkansas’ rich diversity of native plant and

nongame animals,” including species, subspecies, and populations that are “rare, threatened,

endangered or are of special significance to the state.”177 Idaho and Utah define endangered and

threatened species under state law as including only those species identified as such under the

federal ESA. 178 Idaho does not provide any further protections for listed species beyond the

federal ESA. Utah allows certain state entities to “make determinations concerning the

management, protection, and conservation of plant species” listed or proposed for listing under

the federal ESA on state and school or institutional trust lands. 179 Utah does not provide any

additional protections for listed fish, wildlife, or plants beyond the federal ESA.

ESA Section 7: Interagency Consultation

Section 7 consultation under the ESA is the process federal agencies use to interact with the

Services to address the conservation of listed species. Under Section 7(a)(1), federal agencies are

required to use their authorities to carry out programs for the conservation of listed species under

the ESA. The Services note that this provision supports a proactive conservation planning process

by federal agencies that will enable the agencies to plan their actions and programs to allow for

the conservation and recovery of listed species. 180

Section 7(a)(2) requires federal agencies to ensure their discretionary actions, or the actions of

nonfederal parties granted approvals, permits, or funding by federal agencies, are “not likely to

jeopardize the continued existence” of any endangered or threatened species or “adversely modify

critical habitat.”181 Federal agencies undertaking actions, whether directly or through federal

approvals, permits, or funding for nonfederal parties, must consult with FWS or NMFS, as

appropriate, if those actions might affect a listed species or designated critical habitat. 182 This

process is referred to as Section 7 consultation. Federal actions mandated by statute (i.e., that are

not discretionary) do not require Section 7 consultation.

Section 7 Consultation Process and Biological Opinions

The Section 7 consultation requirements apply to federal agency actions, including actions on

federal land and actions on private land with a federal nexus. The Services’ joint regulations on

Section 7 consultations define an agency action as

All activities or programs of any kind authorized, funded, or carried out, in whole or in

part, by Federal agencies in the United States or upon the high seas. Examples include, but

are not limited to:

(a) actions intended to conserve listed species or their habitat;

177 ARK . CODE ANN . §15-45-301. T he statute establishes a Nongame Conservation Committee that may expend funds

collected from voluntary checkoff designations from state income tax refunds “for the purpose of protecting,

preserving, and restoring the nongame resources of the state.” ARK . CODE ANN . §15-45-303.

178

I DAHO CODE ANN. §36-2401; UTAH CODE ANN. §23-13-2.

179 UTAH CODE ANN . §§53C-2-202 & 65A-2-3.

180 50 C.F.R. §402.01 and 84 Federal Register 44976-45018.

181

ESA §7(a)(2), 16 U.S.C. §1536(a)(2).

182 50 C.F.R. §402.02. Action includes any activity authorized, funded, or carried out by a federal agency, including

permits and licenses.

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(b) the promulgation of regulations;

(d) actions directly or indirectly causing modifications to the land, water, or air. 183

Federal agencies must determine whether their proposed actions might affect listed species or

designated critical habitat (i.e., whether the listed species or critical habitat may be present in the

action area). 184 If the agency determines the action is likely to affect a species or critical habitat,

then the agency must consult with the Services on the action’s effects. Consultation usually is

initiated by the action agency but may be initiated at the request of an FWS Regional Director or

NMFS’s Assistant Administrator for Fisheries. 185

The federal action agency must complete a biological assessment (BA) if listed species may be

present in the area that the action would affect. 186 The BA describes the proposed action and its

likely effect on listed species. It also lists activities the agency plans to undertake to mitigate any

adverse effects of the action. The BA must be based on “the best scientific and commercial data

available.”187 Action agencies use the BA to determine whether formal consultation (i.e., a request

for consultation from the agency to the Services that culminates in a biological opinion) is

necessary. 188

To determine whether formal consultation might be needed, a federal action agency can engage in

informal consultation with the Services. (See Figure 3.) Informal consultation is an umbrella

term used to describe all of the correspondence and discussions between an agency and the

Services regarding the proposed action. 189 These interactions may be used to avoid the need for

formal consultation. For example, the action agency, in coordination with any nonfederal

applicant (e.g., permit applicant), might work with the Services on the design of the proposed

action during informal consultations to eliminate the potential for adverse effect on the species or

critical habitat to avoid the need for formal consultation. 190 If the federal action agency

determines during the informal consultation process that the action is not likely to adversely

affect the listed species or designated critical habitat, the agency can request a written

concurrence from the applicable Service; if the Service concurs, the consultation is finished. The

Services are required to respond to this request with either concurrence or nonconcurrence within

60 days, unless the time limit is mutually extended for a period not exceeding 120 days from the

date of the request. 191 Informal consultations under the ESA outnumber formal consultations. In a

2015 study that analyzed consultations from 2008 to 2015, 81,461 informal consultations were

183 50 C.F.R. §402.02.

184 If the agency determines its proposed action will not affect a listed species or critical habitat, then the agency is not

required to undergo consultation. T he agency could be subject to penalties for violating prohibitions under the ESA if

its determination is found to be incorrect.

185 50 C.F.R. §402.14, and see the definition of Director in §402.02.

186 ESA §7(c), 16 U.S.C. §1536(c).

187 ESA §7(a)(2), 16 U.S.C. §1536(a)(2).

188 50 C.F.R. §402.2 (definition of formal consultation); 50 C.F.R. §402.12(a).

189 FWS, “ Consultations: Frequently Asked Questions,” June 10, 2020, at https://www.fws.gov/endangered/what-we-

do/faq.html#:~:text=

Informal%20consultation%20is%20an%20optional,no%20specified%20timeframe%20for%20completion .

190 See 50 C.F.R. §402.13 for more information.

191 50 C.F.R. §402.13.

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completed, compared with 6,829 formal consultations. 192 This study also reported that informal

consultations under Section 7 took an average of 13 days and formal consultations took an

average of 62 days. 193

Figure 3. Informal and Formal Consultation Under the ESA

Source: Congressional Research Service.

Note: Services = U.S. Fish and Wildlife Service and National Marine Fisheries Service.

If the agency requests formal consultation, the ESA has a defined process to be completed under a

specified timeline. (See Table 3.) The agency sends the BA to the appropriate Secretary, where

the appropriate Service analyzes the assessment. If the Secretary finds the action would neither

jeopardize any listed species nor adversely modify critical habitat, the Secretary issues a

biological opinion (BiOp) to that effect. The BiOp includes a written incidental take statement

(ITS). 194 Incidental take is the take of a listed species as a result of an otherwise lawful action. An

ITS states the amount of take of a listed species that is anticipated from the proposed action and

provides the agency with an exemption from the prohibitions on take under Section 9 of the ESA

192 J. W. Malcom and Ya-Wei Li, “Data Contradict Common Perceptions About a Controversial Provision of the U.S.

Endangered Species Act,” Proceedings of the National Academy of Sciences, vol. 112, no. 52 (December 29, 2015).

Hereinafter cited as Malcom and Li, “Data Contradict Common Perceptions.”

193 Malcom and Li, “Data Contradict Common Perceptions.”

194 ESA §7(b)(4), 16 U.S.C. §1536(b)(4).

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for the expected level of take. This exemption is contingent on the agency complying with any

reasonable and prudent measures and the terms and conditions included in the ITS. 195

Alternatively, if the proposed action is judged to jeopardize listed species or adversely modify

critical habitat, the Secretary must suggest any reasonable and prudent alternatives (RPAs) in the

issued BiOp that minimize harm to the species. A BiOp with RPAs also contains an ITS that sets

limits on take for listed species. If no RPAs are feasible, then the agency proposing the action

must (1) forgo the action, (2) modify the action and reinitiate consultation for the revised action,

(3) risk violating the ESA, or (4) obtain a formal exemption from an Endangered Species

Committee (ESC). 196 The great majority of Section 7 consultations result in no jeopardy opinions,

and nearly all of the rest identify RPAs that permit the action agencies to go forward with the

proposed projects. 197

The Secretary generally must conclude consultation and issue a BiOp within 90 days of receiving

an action agency’s BA for a wholly federal action, unless the Secretary and the federal agency

mutually agree to a longer period. 198 For consultations involving a nonfederal party (e.g., permit

applicant), the 90-day period may be extended up to an additional 60 days without the nonfederal

party’s permission; the Services and action agency need only provide the nonfederal party with an

explanation for the delay and the estimated time frame for completion. 199 The Services and action

agency must obtain the nonfederal party’s permission to extend the consultation beyond 150 days

from its initiation. 200 Pursuant to federal regulations, the action agency and the Services may enter

into an agreement to conduct an expedited consultation under Section 7 with an alternative

accelerated timeline established by the action agency and the Services. 201 In general, the Services

complete formal consultations pursuant to the given timelines; however, some consultations may

take a year or more. 202

BiOps may be revised through a reinitiation of formal consultation. After a consultation is

complete, federal agencies may be required to reinitiate consultation with the Services when

certain circumstances arise. Specifically, reinitiation of consultation is required when

195 16 U.S.C. §1536(b)(4). Reasonable and prudent measures are distinct from reasonable and prudent alternatives that

may be provided by the Secretary if the action is likely to jeopardize listed species or adversely modify critical habitat.

Reasonable and prudent measures “refer to those actions the Director believes necessary or appropriate to minimize the

impacts, i.e., amount or extent, of incidental take.” “ Reasonable and prudent alternatives refer to alternative actions

identified during formal consultation that can be implemented in a manner consistent with the intended purpose of the

action, that can be implemented consistent with the scope of th e Federal agency’s legal authority and jurisdiction, that

is economically and technologically feasible, and that the Director believes would avoid the likelihood of jeopardizing

the continued existence of listed species or resulting in the destruction or adverse modification of critical habitat.” 50

C.F.R. §402.02.

196 16 U.S.C. §1536(g); 50 C.F.R. §402.15; 50 C.F.R. Subchapter C; FWS and NMFS, Endangered Species

Conservation Handbook: Procedures for Conducting Consultation and Conference Activities Under Sec tion 7 of the

Endangered Species Act, March 1998, at https://www.fws.gov/endangered/esa-library/pdf/esa_section7_handbook.pdf,

p. 2-11. For more information, see CRS Report R40787, Endangered Species Act (ESA): The Exemption Process, by

Pervaze A. Sheikh. See section on Exemptions for Section 7 Consultation in this report for more information.

197 Malcom and Li, “Dat a Contradict Common Perceptions,” pp. 15844-15849.

198 ESA §7(b)(1), 16 U.S.C. §1536(b)(1); 50 C.F.R. §402.14(e). FWS and NMFS begin the 90-day clock when they

receive a complete biological assessment (BA) with all the information needed for consultation; action agencies are

often asked for more information than the data submitted in the original BA. Action agencies often object to the delays;

the Services respond that consultation requires adequate data about the project.

199

ESA §7(b)(2), 16 U.S.C. §1536(b)(2).

200 ESA §7(b)(2), 16 U.S.C. §1536(b)(2).

201 50 C.F.R. §402.14(l).

202 Malcom and Li, “Data Contradict Common Perceptions.”

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“discretionary Federal involvement or control over the action has been retained or is authorized

by law” and one or more of the following triggering events occurs:



The amount or extent of taking specified in an incidental take statement is

exceeded.

New information on the species or action reveals there is an effect on the species

or critical habitat that was not considered in the BiOp.

The action is sufficiently modified so there is an effect on species and critical

habitat that was not considered in the BiOp.

A new species is listed or critical habitat is designated that may be affected by the

action. 203

Reinitiated consultation follows the same procedures and timelines as formal consultation.

Section 7 consultation also can be conducted at the programmatic level, often referred to as a

programmatic consultation. Programmatic consultations allow federal agencies to consult with

the Services on multiple, frequently occurring, or routine actions in a particular geographic area

or on proposed programs, policies, or regulations that would provide a framework for future

actions. 204 Individual projects conducted under a program covered by a programmatic BiOp

generally still require a separate consultation under Section 7; however, with a programmatic

BiOp in place, this process may be streamlined.

One study found that between 2000 and 2017, the species that were most frequently the subject of

Section 7 consultations included Chinook salmon (Oncorhynchus tshawytscha); steelhead trout

(Oncorhynchus mykiss); Coho salmon (Oncorhynchus kisutch); and several species of sea turtles,

such as the green sea turtle (Chelonia mydas) and the loggerhead sea turtle (Caretta caretta). 205

The study also determined that the U.S. Army Corps of Engineers conducted more Section 7

consultations than any other federal agency, more than triple the number completed by the U.S.

Forest Service, which had the second-most consultations. The three project types associated with

the most Section 7 consultations during the study period were waterways, transportation, and

restoration. 206

Section 7 Consultation and Proposed Species

Section 7 requires federal agencies to confer with the appropriate Secretary on any federal 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 (ESA §7(a)(4), 16 U.S.C. §1536(a)(4)). Proposed species

are “any species of fish, wildlife or plant that is proposed in the Federal Register to be listed under section 4 of the

[Endangered Species] Act.” However, agencies need not limit commitments of resources for the agency action. As

a result of the rulemaking process and limited agency resources, a species may be proposed for listing for months

or years before the species is listed or determined to no longer warrant listing. During that time, federal agencies

and private parties may undertake actions that affect the proposed species. The ESA does not extend any of the

prohibited acts for endangered species to proposed species, so nonfederal parties (e.g., private landowners, state

governments, or nonprofits) generally may engage in any activities or projects that have no federal nexus.

Implementing regulations under 50 C.F.R. §402.10 state that an action agency may hold a conference with the

Services on any action that is likely to jeopardize a proposed species or to destroy or modify its proposed critical

203 50 C.F.R. §402.16.

204

50 C.F.R. §402.13(l).

205 M. J. Evans, J. W. Malcom, and Y. W. Li, “Novel Data Show Expert Wildlife Agencies Are Important to

Endangered Species Recovery,” Nature Communications, vol. 10 (August 1, 2019). Hereinafter cited as Evans,

Malcom, and Li, “Novel Data.”

206 Evans, Malcom, and Li, “Novel Data.”

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habitat. The conference is designed to assist the federal agency and the applicant (if any) 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 the Services to advise a federal agency on ways to minimize or avoid

adverse effects on a proposed species. A federal agency may, however, choose to undertake the more extensive

and formal consultation process even at the proposed listing stage to avoid duplication of effort later.

For more information on conference requirements for proposed species, see FWS and NMFS, Consultation

Handbook: Procedures for Conducting Consultation and Conference Activities Under Section 7 of the Endangered Species

Act, March 1998.

Exemptions for Section 7 Consultation

If the Services cannot identify any RPAs for a project to avoid jeopardizing listed species or

adversely modifying designated critical habitat and if other required conditions are met, an action

may be eligible to receive a formal exemption from the requirement that the action not jeopardize

listed species or adversely modify critical habitat. 207 In addition, any action covered by a formal

exemption is deemed to not result in take of a listed species. 208 If an agency wants to obtain a

formal exemption, the agency (or the affected governor[s] or license applicant[s]) may apply to

the Secretary, who passes on the application to an ESC for an exemption. 209 Exemptions are

available for specific actions (e.g., water withdrawals) rather than for all actions related to a

particular species (e.g., Delta smelt). An ESC, which decides whether to provide an exemption for

the action, is composed of six specified federal officials and one individual from each affected

state. 210 Five members or their representatives need to be present for a quorum; only members—

not their representatives—count toward a quorum if the committee is voting, because only

members can vote. At least five votes are required to allow an exemption. 211

Under Section 7(g), to be eligible for consideration of an exemption, the Secretary must

determine within 20 days, or a time period otherwise agreeable to the Secretary and the applicant,

that the applicant

207



completed consultation requirements “in good faith and made a reasonable and

responsible effort to develop and fairly consider modifications or reasonable and

prudent alternatives”;



conducted any required BAs; and

“to the extent determinable ... refrained from making any irreversible or

irretrievable commitment of resources.”212

ESA §7(h), 16 U.S.C. §1536(h).

208 ESA §7(o)(1), 16 U.S.C. §1536(o)(1).

209 ESA §7(g), 16 U.S.C. §1536(g).

210

T he six federal officials are the Secretaries of the Interior (chair), Agriculture, and the Army; the Chair of the

Council of Economic Advisors; and the Administrators of NOAA and the Environmental Protection Agency. 16 U.S.C.

§1536(e)(3).

211 In the event that more than one state is affected by the action, the regulations provide that the states collectively cast

one vote. 50 C.F.R. §453.05.

212 ESA §7(g)(3), 16 U.S.C. §1536(g)(3). Such “irreversible or irretrievable commitment[s] of resources” are those that

would foreclose the formulation or implementation of RPAs that would avoid jeopardizing the species and/or adversely

modifying critical habitat. ESA §7(d), 16 U.S.C. §1536(d).

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These qualifying requirements ensure the exemption process is meaningful and consideration of

the issues will not be preempted by actions already taken. Additional requirements for an

application are contained in the relevant regulations. 213

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 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.214

There have been three completed applications for an exemption under this process (two granted)

and three other instances in which applications were filed but the applications were withdrawn or

abandoned. 215

The ESA also provides alternative avenues for granting exemptions under certain circumstances.

Specifically, exemptions may be approved under alternative procedures when the action concerns

international treaty obligations, 216 national security, 217 and presidentially declared disasters. 218 The

ESA does not have a general provision that allows exemptions in other emergency conditions.

ESA Section 9: Prohibitions

Section 9 of the ESA enumerates various acts that are prohibited with respect to endangered

species. For threatened species not covered by FWS’s blanket 4(d) rule, the Services may apply

Section 9 prohibitions to such threatened species through a species-specific 4(d) rule. Absent a

species-specific 4(d) rule, the Section 9 prohibited acts do not extend to threatened species.219

The Section 9 prohibitions include the following:



Importing or exporting endangered species into or out of the United States

Taking endangered species within the United States or U.S. territorial seas and

taking such species on the high seas

213 50 C.F.R. parts 450-453.

214 ESA §7(h)(1)(A), 16 U.S.C. §1536(h)(1)(A).

215

For more information, see CRS Report R40787, Endangered Species Act (ESA): The Exemption Process, by

Pervaze A. Sheikh.

216 ESA §7(i), 16 U.S.C. §1536(i).

217

ESA §7(j), 16 U.S.C. §1536(j).

ESA §7(p), 16 U.S.C. §1536(p). However, 50 C.F.R. §13.4 states that in emergency conditions, the FWS Director

“may approve variations from the requirements of this part [the general permit procedures] when he finds that any

emergency exists and that the proposed variations will not hinder effective administration of [the subchapter on

permits], and will not be unlawful.”

218

219 In the absence of a species-specific 4(d) rule for threatened species listed by FWS before September 26, 2019, the

blanket 4(d) rule extended essentially the same protections and prohibitions to those species as apply to endangered

species.

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

Possessing, selling, or transporting any unlawfully taken endangered species

Delivering, receiving, transporting, or selling in interstate or foreign commerce

any endangered species

Violating any regulation promulgated by FWS or NMFS pertaining to any

endangered or threatened species 220

Similar prohibitions apply to endangered plants, except the prohibitions most similar to the take

prohibitions generally apply only to endangered plant species located in areas under federal

jurisdiction. 221

The ESA also prohibits attempting to commit, soliciting another to commit, or causing to be

committed any prohibited act. 222 The ESA’s prohibitions apply broadly to any person (as defined

by the act) subject to the jurisdiction of the United States. 223 Sections 9 and 10 of the ESA allow

for certain exceptions from the prohibitions. 224

Import and Export Provisions Under Section 9 of the ESA

The ESA generally requires any person who engages in the business of importing or exporting fish, wildlife, or

plants to obtain permission from the appropriate Secretary. The ESA does not specify that the species must be

listed, thus making the law broadly applicable to all species, with some exceptions. Those persons who are

required to receive permission must keep records on their imports and exports; provide access to their place of

business for inspections; file required reports with the Secretary; and use certain ports designated by the

Secretary, unless the Secretary deems it appropriate and consistent with the ESA to permit importation or

exportation elsewhere.

Source: ESA §9(d)-(f), 16 U.S.C. §1538(d)-(f).

ESA Section 10: Exceptions

Section 10 of the ESA authorizes the Secretary to issue a permit to exempt certain actions from

ESA prohibitions. Eligible actions include taking species for scientific purposes, enhancing the

survival of listed species, and incidental taking of listed species during otherwise lawful

actions. 225 The following sections discuss these exemptions.

Permits for Scientific Purposes and Enhancing the Survival of

Species

Section 10(a)(1)(A) authorizes the Secretary to issue permits to carry out acts otherwise

prohibited by Section 9 of the ESA for scientific purposes and to “enhance the propagation and

survival” of listed species; these permits may be used to establish experimental populations. 226

Scientific permits issued by the Services may authorize take of listed species to study the biology

and long-term survival needs of a listed species, among other things. The Services also issue

220 ESA §9(a), 16 U.S.C. §1538(a).

221

ESA §9(a)(2), 16 U.S.C. §1538(a)(2).

222 ESA §9(g), 16 U.S.C. §1538(g).

223

ESA §9(a), 16 U.S.C. §1538(a).

224 ESA §§9(b) and 10, 16 U.S.C. §§1538(b) and 1539.

225 ESA §10, 16 U.S.C. §1539(a).

226 ESA §10(a)(1), 16 U.S.C. §1539(a)(1).

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recovery permits under this same authority. Recovery permits are issued to assist in the recovery

of listed species and may include exemptions from prohibitions of take. 227 Some activities that

might be authorized under a recovery permit include genetic studies, abundance surveys, and

telemetric monitoring (i.e., tracking species using sensors) of listed species.

The Services issue enhancement of survival permits (enhancement permits) for activities that

provide a conservation benefit for listed species or unlisted species in the event they become

listed in the future. For example, enhancement permits are used to approve activities in

conjunction with a candidate conservation agreement or a safe harbor agreement (see textbox

below).

Safe Harbor Agreements

Because many listed species inhabit private lands, the Services created policies that encourage private landowners’

involvement in the conservation of these species. To incentivize landowners to aid in species conservation, the

Services may use safe harbor agreements (SHAs). SHAs are voluntary agreements between the Services and

nonfederal landowners that provide nonfederal landowners assurances that the Services will not require changes

in management activities on their land if additional listed species enter into their property or if the distribution of

listed species increases on their property if a landowner conducts conservation actions that benefit listed species

or species that might be listed in the future. The assurance is provided by an Enhancement of Survival Permit

issued to the property owner. The permit authorizes incidental take of listed species from actions taken by the

landowner in the SHA.

Some conservation activities that might be covered under SHAs include restoring habitat for species; reducing

habitat fragmentation; and creating buffers for habitat, such as vegetative buffers for streams, among others. An

SHA benefits landowners by ensuring potential restrictions on land use or activities will not be applied if newly

listed species inhabit their lands or if existing listed species move onto their land. This assurance is provided by an

enhancement permit issued to the landowner. The permit can authorize incidental take of species that may result

from conservation activities included in the SHA.

Source: FWS, “Safe Harbor Agreements: Frequently Asked Questions,” January 2020, at https://www.fws.gov/

endangered/landowners/landowners-faq.html.

Enhancement permits can be issued for several other activities, including captive breeding

programs that aim to improve the survivorship, reproduction, genetic vitality, and management of

populations. Enhancement permits also can be used to exhibit living listed species to educate the

public on the species’ conservation needs and ecological roles. 228 Zoos, for example, may obtain

such permits to conserve listed species. 229

Enhancement permits sometimes are issued to import and export listed species. An enhancement

permit may be used to import sport-hunted trophies of foreign species listed under the ESA into

the United States. These enhancement permits may be justified based on the incentives allowing

such imports to provide for increasing the survival of the species in its native habitat. For

example, if trophy hunters are allowed to harvest a limited number of animals, and if funds

generated by the hunters’ activities (e.g., through permits or taxes) are transferred to a

conservation program that supports a population of the same species, then the limited take of

individuals through hunting could enhance the species’ survival by providing an incentive for

conservation.

227 FWS, Recovery 10(a)(A)(1) Permits Program , April 23, 2020.

A. Haas, “Interpreting ‘Enhancement of Survival’ in Granting Section 10 Endangered Species Act Exemptions to

Animal Exhibitors,” Pace Environmental Law Review, July 2015, pp. 956-982. Hereinafter cited as A. Haas,

“Enhancement of Survival.”

228

229 A. Haas, “Enhancement of Survival.”

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The ESA states that the Secretary may grant permits under Section 10(a)(1)(A) if the Secretary

finds that permits were applied for in good faith, will not disadvantage endangered species, and

will be consistent with the purposes and policy of the ESA. 230

Permits for Incidental Taking of Species and Habitat Conservation

Plans

For actions by nonfederal parties that might result in take of a listed species but have no federal

nexus (e.g., a loan or permit), the Secretary may issue permits to allow incidental take of listed

species for otherwise lawful actions.231 To obtain an incidental take permit (ITP), a nonfederal

entity must submit a permit application and a habitat conservation plan (HCP), under Section

10(a)(1)(B) of the ESA. 232 The HCP describes the anticipated effects of the nonfederal applicant’s

action on listed species, 233 as well as the steps to be taken to minimize and mitigate that impact,

funding for the mitigation, alternatives that were considered and rejected, and any other measures

the Secretary may require. HCPs also must comply with other policies by including biological

goals and outcomes for the species covered by the HCP, adaptive management provisions, 234

monitoring protocols, permit duration, and public participation in the process. The permit

applicant must use the best available science when creating HCPs and ITPs, and in some cases

HCPs are reviewed by independent scientists. 235

Once the permit application and draft HCP are completed, they generally are submitted to the

Services along with an implementation agreement. The Secretary evaluates the permit application

(including the HCP) and determines if it meets and abides by the following criteria specified

under the ESA:



The taking of species will be incidental.

The applicant will minimize and mitigate the action’s effects on species to the

maximum extent practicable.



The applicant will ensure that adequate funding of the mitigation measures is

required.

The taking of the species will not appreciably reduce the survival and recovery of

the species in the wild.

Any other measures prescribed by the Secretary.236



230 ESA §10(d), 16 U.S.C. §1539(d).

231 ESA §10(a), 16 U.S.C. §1539(a).

ESA §10(a)(2)(A), 16 U.S.C. §1539(a)(2)(A). Also, see 50 C.F.R. §17.3, which defined conservation plan as “ the

plan required by section 10(a)(2)(A) of the ESA that an applicant must submit when applying for an incidental take

permit. Conservation plans also are known as ‘habitat conservation plans’ or ‘HCPs.’”

232

233 ESA §10(a)(2)(A), 16 U.S.C. §1539(a)(2)(A).

234 Adaptive management is the process of incorporating new scientific and programmatic information into the

implementation of a project or plan to ensure the activity’s goals are being reached efficiently. It promotes flexible

decision-making to modify existing activities or create new activities if new circumstances arise (e.g., new scientific

information) or if projects are not meeting their goals.

235

FWS, Habitat Conservation Plans Under the Endangered Species Act, April 2011, at https://www.fws.gov/

endangered/esa-library/pdf/hcp.pdf.

236 ESA §10(a)(2)(B), 16 U.S.C. §1539(a)(2)(B).

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Because the issuance of an ITP is considered a federal action by the Services, FWS or NMFS

must complete an intra-Service consultation subject to Section 7 and issue a BiOp assessing the

effects of the ITP on the listed species and critical habitat. 237 Upon completion of the Section 7

consultation, an ITP allows nonfederal entities or persons to legally proceed with a project that

incidentally takes listed species as specified under the ITP. The permit holder also benefits from

the No Surprises regulation;238 under this regulation, private landowners are assured that if

unforeseen circumstances arise, FWS will not require an additional commitment of resources to

address species in an HCP without the landowner’s consent. 239 This policy was created to

incentivize private landowners to conserve species and their habitat using Section 10 permits. The

actions agreed to in an HCP are made binding through the ITP. Typically, ITPs have an expiration

date; however, mitigation under the HCP can be in perpetuity. If the terms of the ITP are violated,

the action could result in illegal take under Section 9 of the ESA.

All applications for exceptions or permits under Section 10 must be published in the Federal

threatened and no alternatives are available to the applicant). In addition, any information

received as part of the application must be made public. 240

Comparison of Section 10 and Section 7 Consultation

Permitting under Section 10 and consulting under Section 7 lead to an ITP and an ITS,

respectively, which allow applicants to proceed with projects or actions that affect listed species

without violating the take prohibitions. Table 3 summarizes some similarities and several

differences between the processes under Section 10 and Section 7. The comparison below is not

comprehensive but focuses on key aspects of the two processes under the ESA.

Table 3. Comparison of Section 7 Consultation and Section 10 Permitting

Under the ESA

Characteristic

Section 7 Consultation

Section 10 Permitting

Applicants

Federal agencies or in some cases

nonfederal agencies that have been assigned

as an applicant under various authorities.

Nonfederal entities that are proposing actions

with no federal nexus.

Applicable

Actions

Federal actions or nonfederal actions that

have a federal nexus.

Nonfederal entities that believe their

otherwise lawful activities will result in the

incidental take of a listed species under the

ESA.

Applicable

Biological

Conditions

Section 7 consultation is initiated when a

federal agency determines a project or

action might jeopardize species listed under

the ESA or adversely modify designated

critical habitat. Consultation applies to

plants, fish, and wildlife.

Section 10 permit is sought when actions are

likely to result in take of a listed species and any

taking is incidental to carrying out the

otherwise lawful activity. This applies only to

wildlife, since there is no prohibition on take

for plants.

237 FWS and NOAA, Habitat Conservation Planning and Incidental Take Permit Processing, FWS and NOAA

Handbook, December 21, 2016, p. 3-27, at https://www.fws.gov/endangered/esa-library/pdf/HCP_Handbook.pdf.

238 50 C.F.R. §17.3, §17.22(b)(5) and §17.32(b)(5).

239 50 C.F.R. §17.3, §17.22(b)(5) and §17.32(b)(5).

240 ESA §10(d), 16 U.S.C. §1539(d).

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Characteristic

Section 7 Consultation

Section 10 Permitting

Scope

Section 7 covers a proposed project or

action and considers the effect on one or

more species.

Section 10 permit covers a species or multiple

species and the effects of actions on those

species.

Application

Process

Agencies may consult informally with the

U.S. Fish and Wildlife Service and the

National Marine Fisheries Service (the

Services) before requesting a formal

consultation. Informal consultations entail

communication with the Services about

whether formal consultation is required and

whether the action may be modified to

avoid the need for formal consultation. A

federal agency may prepare a biological

assessment (BA) before informal

consultation and for formal consultation.

Formal consultation occurs when the action

may affect a listed species. The Services

review the BA and issue a biological opinion

(BiOp).

The nonfederal entity applies for an incidental

take permit (ITP) to lawfully carry out its

action with take of listed species.

The applicant for an ITP must submit a habitat

conservation plan (HCP) that shows the

action’s likely impact, steps to minimize and

mitigate that impact, funding sources for the

mitigation, alternatives that were considered

and rejected, and any other measures the

Secretary may require.

Time Limits

The appropriate Secretary is to complete

consultation within 90 days, unless the

Secretary and the applying federal agency

agree to extend the time period—with

notice to or permission of any nonfederal

applicant, depending how long the extension

is.

The Secretary has 45 days after a formal

consultation to issue a BiOp.

There are no time limits in the ESA for

completing an HCP and issuing an ITP.

Public Review

There is no requirement that the Services

publish a draft BiOp for public review. Draft

BiOps can be provided to the federal agency

or applicant for review.

The ESA requires a 30-day comment period on

ITPs; however, if National Environmental

Policy Act requirements are concurrently

being met, the comment period could be

longer.

Critical Habitat

The adverse modification of critical habitat

by an action could trigger a Sect

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