U.S. Fish & Wildlife Service

January 1998

ESA Basics

30 Years of Protecting Endangered

Species

When Congress passed the Endangered

Species Act (ESA) in 1973, it recognized

that our rich natural heritage is of

“esthetic, ecological, educational,

recreational, and scientific value to our

Nation and its people.” It further

expressed concern that many of our

nation’s native plants and animals were in

danger of becoming extinct.

The purpose of the ESA is to protect and

recover imperiled species and the

ecosystems upon which they depend. It is

administered by the Interior Department’s

U.S. Fish and Wildlife Service (FWS) and

the Commerce Department’s National

Marine Fisheries Service (NMFS). The

FWS has primary responsibility for

terrestrial and freshwater organisms,

while the responsibilities of NMFS are

mainly marine species such as salmon and

whales.

Under the ESA, species may be listed as

either “endangered” or “threatened.”

Endangered means a species is in danger of

extinction throughout all or a significant

portion of its range. Threatened means a

species is likely to become endangered

within the foreseeable future throughout

all or a significant portion of its range. All

species of plants and animals, except pest

insects and non-native species, are eligible

for listing as endangered or threatened.

For the purposes of the ESA, Congress

defined species to include subspecies,

varieties, and, for vertebrates, distinct

population segments.

As of May 1, 2006, the FWS has listed 1,868

species worldwide as endangered or

threatened, of which 1,300 occur in the U.S.

How are Species Listed?

Section 4 of the ESA specifies that a

species must be listed as endangered or

threatened solely on the basis of its

biological status and threats to its

existence. When evaluating a species for

listing, five factors are considered: 1)

damage to, or destruction of, a species’

habitat; 2) overuse of the species for

commercial, recreational, scientific, or

educational purposes; 3) disease or

predation; 4) the inadequacy of existing

Bay Checkerspot Butterfly, USFWS Photo

protection; and 5) other natural or humanrelated threats to the species’ survival.

When one or more of these factors imperils

the survival of a species, the FWS takes

action to protect it. To ensure the accuracy

of the data, the FWS decides all listings

using sound science and peer review.

Candidates for Listing

The FWS also maintains a list of

“candidate” species. These are species for

which there is enough information to

warrant proposing them for listing but that

have not yet been proposed because of

higher listing priorities. While listing

actions of higher priority go forward, the

FWS works with states, tribes, private

landowners, private partners, and other

federal agencies to carry out conservation

actions for these species to prevent further

decline and possibly eliminate the need to

list them.

Protection

The ESA protects listed species and their

habitats by prohibiting the “take” of listed

animals and the interstate or international

trade in listed plants and animals,

including their parts and products, except

under federal permit. Such permits

generally are available only for certain

conservation and scientific purposes.

What is “Take”?

The ESA makes it unlawful for a person to

take a listed animal without a permit. Take

is defined as “to harass, harm, pursue,

hunt, shoot, wound, kill, trap, capture, or

collect or attempt to engage in any such

conduct.” Through regulations, the term

“harm” is defined as “an act which actually

kills or injures wildlife. Such an act may

include significant habitat modification or

degradation where it actually kills or

injures wildlife by significantly impairing

essential behavioral patterns, including

breeding, feeding, or sheltering.” Listed

plants are not protected from take,

although it is illegal to collect or

maliciously harm them on federal lands.

Protections from commercial trade and the

effects of federal actions do apply for

plants. Some state laws contain their own

restrictions on the take of listed species.

Recovery

The law’s ultimate goal is to “recover”

species so they no longer need protection

under the ESA. Recovery plans describe

the steps needed to restore a species to

ecological health. Appropriate public and

private agencies and institutions and other

qualified persons assist in developing and

implementing recovery plans. Involving

the public and interested stakeholders in

developing these plans is encouraged.

Recovery teams may be appointed to

develop and implement recovery plans.

Federal Activities

Section 7 of the ESA requires federal

agencies to use their legal authorities to

promote the conservation purposes of the

law. This section also requires federal

agencies to consult with the FWS or

NMFS to ensure that actions they

authorize, fund, or carry out will not

jeopardize listed species. The consulting

agency then receives a “biological opinion”

on the proposed action. In the relatively

few cases where the FWS or NMFS

determines that the proposed action will
January 1998

jeopardize the species, they must offer

“reasonable and prudent alternatives”

about how the proposed action could be

modified to avoid jeopardy. It is very rare

to withdraw or terminate projects

because of jeopardy to a listed species.

The ESA also requires the designation of

“critical habitat” for listed species when

it is judged to be “prudent and

determinable.” Critical habitat includes

geographic areas that contain the

physical or biological features essential

to the conservation of the species and

that may need special management or

protection. Critical habitat designations

affect only federal agency actions or

federally funded or permitted activities.

Federal agencies are required to avoid

“adverse modification” of designated

critical habitat.

Critical habitat may include areas not

occupied by the species at the time of

listing but that are essential to its

conservation. An area can be excluded

from critical habitat designation if an

economic analysis determines that the

benefits of excluding it outweigh the

benefits of including it, unless failure to

designate the area as critical habitat may

lead to extinction of the listed species.

The ESA provides a process for

exempting development projects from

the restrictions of the law if a Cabinetlevel “Endangered Species Committee”

decides the benefits of the project clearly

outweigh the benefits of conserving a

species. Since its creation in 1978, the

Committee has only been convened three

times to make this decision.

Working with States

The protection of listed species is also

achieved through partnerships with the

states. Section 6 of the ESA encourages

each state to develop and maintain

conservation programs for resident

federally-listed threatened and

endangered species. Federal financial

assistance and incentives are available to

promote state participation. Some state

laws and regulations are even more

restrictive than the ESA in granting

exceptions or permits.

Working with Landowners

Two-thirds of federally listed species

have at least some habitat on private

lands. The FWS has developed an array

of tools and incentives to protect private

landowners’ interests while encouraging

them to manage their lands to benefit

listed and at-risk species.

Habitat Conservation Plans

Section 10 of the ESA provides relief to

private landowners who want to develop

land inhabited by listed species.

Landowners can receive a permit for the

take of a listed species that may occur

incidental to otherwise legal activities,

provided they have developed an

approved habitat conservation plan

(HCP). HCPs include an assessment of

the likely impacts on the species from

the proposed action, the steps that will

be taken to minimize and mitigate those

impacts, and the funding available to

carry out those steps. When the FWS

approves the HCP, the landowner can

apply for an “incidental take” permit,

which allows them to proceed with the

proposed action.

HCPs benefit not only the landowners

but also the species by securing and

managing important habitat.

Safe Harbor Agreements

A Safe Harbor Agreement (SHA)

provides regulatory assurance for

landowners who voluntarily aid in the

recovery of listed species by improving

or maintaining wildlife habitat on their

lands. Under an SHA, a landowner can

manage the property enrolled in the

SHA and, at the end of the agreement,

return it to originally agreed-upon

“baseline” conditions for the species and

its habitat, even if this means incidentally

taking individuals of the covered species.

Candidate Conservation Agreements

It is easier to conserve species before

they need to be listed as endangered or

threatened. Candidate Conservation

Agreements (CCAs) are voluntary

agreements between landowners

(including federal land managing

agencies) and one or more other parties

that are intended to reduce or remove

the threats to candidate or at-risk

species. The parties to the CCA work

with the FWS to design the voluntary

conservation measures and monitor the

effectiveness of plan implementation.

Candidate Conservation Agreements with

Assurances

Under a Candidate Conservation

Agreement with Assurances (CCAA),

non-federal landowners volunteer to

work with the FWS on plans to conserve

candidate and at-risk species. In return,

the landowners receive regulatory

assurances that, if a covered species is

eventually listed, they will not be

required to do anything beyond what is

specified in the agreement, and they will

receive an incidental take permit if the

species becomes listed.

Conservation Banks

Conservation banks are lands that are

permanently protected and managed as

mitigation for the loss elsewhere of listed

species and their habitats. Conservation

banking is a free market enterprise

based on supply and demand of

mitigation credits. By mitigating

multiple development projects at a

conservation bank, all parties involved,

including the species, benefit. If the

habitat supports a specific species (or

multiple species), the landowner agrees

to preserve and manage the land in

perpetuity. In return, the landowner is

given mitigation credits that can be sold

to other landowners who need to mitigate

for impacts on listed species resulting

from activities on their lands.

Endangered Species Grants

The ESA authorizes a number of federal

grant programs to promote the

conservation and recovery of listed

plants and animals. Grants issued under

section 6 of the ESA go to state and

territorial agencies, which often are in

partnership with private landowners.

Private individuals and groups can

receive “Private Stewardship Grants” for

their voluntary efforts on private

property for the benefit of listed and atrisk species. The Service offers several

other financial assistance opportunities

that may benefit such species. Please

visit www.fws.gov/grants for additional

information.

International Species

The ESA also implements U.S.

participation in the Convention on

International Trade in Endangered

Species of Wild Fauna and Flora

(CITES), a 169-nation agreement

designed to prevent species from

becoming endangered or extinct due to

international trade. The law prohibits

trade in ESA-listed species except under

CITES permits.

For More Information

For additional information about

threatened and endangered species,

landowner tools, grants, and current

recovery efforts, contact the U.S. Fish

and Wildlife Service at the address below,

or visit http://www.fws.endangered.

U.S. Fish and Wildlife Service

Endangered Species Program

4401 N. Fairfax Drive, Room 420

Arlington, VA 22203

http://www.fws.endangered

May 2006