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Endangered Species Act. Definitions and Acronyms List

UPDATED April 22, 2024

  • Action – A federal action refers to a decision, proposal to do something, or a policy implemented by the government.
  • 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 (BO) – The Services analyze the effects of a proposed action to ESA-listed species or designated critical habitat and produce a biological opinion[2].
  • Bulletins Live! Two (BLT) – Sets forth geographically specific pesticide use limitations for the protection of federally listed species and their designated critical habitat[3].
  • Critical Habitat – Area essential for the conservation of a threatened or endangered species5.
  • 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[4]. 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.
  • Endangered Species – Any species which is in danger of extinction throughout all or a significant portion of its range[5].
  • 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 [6].
  • Environmental Protection Agency (EPA) – Has responsibility for regulating pesticides in the U.S. Works with the Services and USDA to ensure that pesticide registrations do not jeopardize listed species or adversely modify their designated critical habitat 1.
  • Extinct – No longer in existence, i.e., no individuals of the species exist [7].
  • Extirpate – Locally extinct, other populations of the species exist elsewhere 6.
  • Federal Insecticide Fungicide and Rodenticide Act (FIFRA) – Federal statute that governs the registration, distribution, sale and use of pesticides in the U.S.[8]
  • FIFRA Interim Ecological Mitigations (IEM) – A menu of mitigation measures that can be implemented to reduce spray drift and pesticide runoff with a goal of protecting listed species. These measures will be considered during proposed interim decisions (PID)[9].
  • Fish and Wildlife Service (FWS) – Part of the Department of Interior and along with NMFS tasked with protecting listed species and their habitat. The FWS works to restore and protect healthy populations of fish, wildlife, plants and the environments upon which they depend.
  • Frequently Asked Questions (FWS) – Fish and Wildlife list of frequently asked questions regarding the Endangered Species Act 12.
  • Herbicide Strategy (HS) – The EPA has developed a series of mitigation measures to minimize herbicide impacts on listed species and their habitat 12.
  • Incidental Take – Is an unintentional take, but not unexpected taking[10]. See Take below.
  • Interim Decision (ID) – EPA may issue an interim decision before completing the registration review [11].
  • Jeopardy/Adverse Modification (J/AM) – The Services, in consultation with the EPA, determine if use of a pesticide will lead to directly cause harm to a species or negatively affect it’s critical habitat 5.
  • Likely to Adversely Affect (LAA) – Determination that use of a pesticide may affect and is likely to adversely affect the listed species or its critical habitat 5.
  • Listed Species – Endangered and threatened species as listed under the ESA.
  • Mitigation – Projects or programs that help offset negative impacts to species-at-risk5.
  • National Marine Fisheries Service (NMFS) – Also known as NOAA Fisheries, part of the Department of Commerce and along with FWS tasked with protected listed species and their habitat. Responsible for the protection, conservation, and recovery of endangered and threatened marine and anadromous (fish, like salmon, that migrate up rivers from the sea to spawn) species.
  • Not Likely to Adversely Affect (NLAA) – Determination that use of a pesticide may affect but is not likely to adversely affect the listed species or its critical habitat 5.
  • Pesticide Use Limitation Area (PULA) – These are the geographic areas where pesticide use limitations exist to protect federally listed species and their designated critical habitat. Bulletins Live! Two Tutorial3.
  • Proposed Interim Decision (PID) – The EPA may issue a proposed interim decision for a registration decision if additional assessments need to be conducted 10.
  • Reasonable and Prudent Alternatives (RPA) – Alternative methods that that could be used in place of the proposed action to avoid the likelihood of harming a species or adverse modification to its critical habitat. Reasonable and prudent alternatives are developed when a biological opinion, written by the Services, concludes that jeopardy or adverse modification may occur[12].
  • 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. Reasonable and prudent measures are developed when a biological opinion is written by the Services.
  • Reregistration of a Pesticide – The EPA reviews all registered pesticides every 15 years to make sure they do not pose unreasonable adverse effects to human health and the environment. Since science is constantly changing new information may change the EPA’s assessment of the pesticide and its effects[13].
  • Services – Fish and Wildlife Service (FWS) and National Marine Fisheries Service (NMFS) which together are called the Services are tasked by the ESA to protect listed species and critical habitat. When an agency has a proposed action that might affect a listed species or its habitat, they consult with one or both of the agencies that helps enforce the ESA, the FWS or the NMFS (this is known as “a consultation” with “the Services”)
  • Take – To harass, harm, pursue, hunt, shoot, wound, kill, trap, capture, or collect, or to attempt to engage in any such conduct 5.
  • 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.
  • United States Department of Agriculture (USDA) – The USDA works with the EPA and Services to make sure that pesticide registrations do not jeopardize listed species or their critical habitat.
  • Vulnerable Species Pilot (VSP) – The EPA identified a small number of vulnerable species, identified mitigations to protect them from pesticides, and will implement these across different types of pesticides[14].

Definitions and acronyms provided by the ESA Committee of the Weed Science Society of America.  For more information see our ESA webpage  https://wssa.net/endangered-species/ 

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

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

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

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

[8] EPA, Federal Insecticide, Fungicide, and Rodenticide Act. (FIFRA) and Federal Facilities https://www.epa.gov/enforcement/federal-insecticide-fungicide-and-rodenticide-act-fifra-and-federal-facilities

[9] EPA, EPA Advances Early Pesticides Protections for Endangered Species, Increases Regulatory Certainty for Agriculture. https://www.epa.gov/pesticides/epa-advances-early-pesticides-protections-endangered-species-increases-regulatory

[10] NOAA, Glossary: Endangered Species Act. NOAA Fisheries Glossary ESA

[11] EPA, Registration Review Process. https://www.epa.gov/pesticide-reevaluation/registration-review-process#action

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

[13] EPA, Registration Review Process. Registration Review Process | US EPA

[14] EPA, Implementing EPA’s Workplan to Protect Endangered and Threatened Species from Pesticides: Pilot Projects.  https://www.epa.gov/endangered-species/implementing-epas-workplan-protect-endangered-and-threatened-species-pesticides#species