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Endangered Species Act. Definitions and Acronyms List

UPDATED December 12, 2023

  • Biological Evaluation (BE) – The EPA conducts an ecological assessment of the potential risks a pesticide may pose to ESA-listed species and any designated critical habitat for the species. This results in an “effects determination”, also referred to as a biological evaluation[1].
  • Biological Opinion – The Services analyze the effects of a proposed action to ESA-listed species or designated critical habitat [2].
  • Bulletins Live! Two – Sets forth geographically specific pesticide use limitations for the protection of listed species and their designated critical habitat[3].
  • Endangered species – Any species which is in danger of extinction throughout all or a significant portion of its range[4].
  • Threatened species – Any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range4.
  • Endangered Species Act (ESA) – The ESA (1973) established protections for fish, wildlife, and plants that are listed as threatened or endangered, provides for interagency cooperation to avoid take of listed species, and for preparing and implementing plans for their recovery [5].
  • Extinct – No longer in existence, i.e., no individuals of the species exist [6].
  • Extirpate – Locally extinct, other populations of the species exist elsewhere 6.
  • Delisted species – Is a species that was formerly listed as threatened or endangered under the Endangered Species Act, but has since been removed from the lists of endangered and threatened species[7]. Species are “delisted” for three reasons:
    • The species has recovered to the point that it no longer needs ESA protection.
    • The original information warranting listing has been shown to be incorrect, or new information suggests that the species is not actually endangered or threatened.
    • The species has become extinct.
  • Designated Critical Habitat – Defined as specific areas essential to the conservation of the species 4.
  • Mitigation – Projects or programs that help offset negative impacts to species-at-risk5.
  • Pesticide Use Limitation Area (PULA) – These are the geographic areas where pesticide use limitations exist to protect listed species and their designated critical habitat. Bulletins Live! Two Tutorial3 .
  • Reasonable and Prudent Alternatives (RPA) – Alternative methods that would avoid the likelihood of jeopardy to the species or adverse modification of critical habitat when a biological opinion reaching a jeopardy or adverse modification conclusion[8].
  • Reasonable and Prudent Measures (RPM) – Actions necessary to minimize the impacts of incidental take that is anticipated to result but is not likely to jeopardize the species or adversely modify designated critical habitat8.
  • Take – To harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct 5.
    • Incidental take – An unintentional, but not unexpected, taking.
  • Services – Fish and Wildlife Service (FWS), part of Department of the Interior, and National Marine Fisheries Service (NMFS), part of the Department of Commerce

[1] EPA, Assessing Pesticides under the Endangered Species Act, Assessing Pesticides under the Endangered Species Act | US EPA

[2] FWS, ESA Section 7 Consultation, ESA Section 7 Consultation | U.S. Fish & Wildlife Service (fws.gov)

[3] EPA, Endangered Species Protection Bulletins, Endangered Species Protection Bulletins | US EPA

[4] FWS, Endangered Species Act, Section 3. Definitions, Section 3. Definitions | U.S. Fish & Wildlife Service (fws.gov)

[5] FWS, Endangered Species Act 1973, Endangered Species Act | U.S. Fish & Wildlife Service (fws.gov)

[6] FWS, Conservation Planning Handbook Glossary. habitat-conservation-planning-handbook-glossary.pdf (fws.gov)

[7][7] FWS, Delisting a Species, Delisting a Species Fact Sheet (fws.gov)

[8] FWS, Endangered Species Ecological Services, Endangered Species Consultations Frequently Asked Questions. (nrc.gov)