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  2. EPA EcoBox
  3. Receptors

EPA EcoBox Tools by Receptors - Endangered, Threatened or Other Species of Concern

On this page:
  • Overview
  • Tools

Overview

Species with especially far-reaching effects on an ecosystem are called keystone species. These species differ from dominant (i.e., abundant) species in that their effects are much larger than would be predicted from their abundance. They have a disproportionate effect on community composition and ecosystem function. A keystone species' presence is often the lone reason for the presence of other organisms and/or the maintenance of unique ecological areas. A keystone species is not always a dominant controlling agent across its entire range, through all stages of its life cycle, or at all times of the year (Watershed Academy Web).

Endangered Species

Endangered species are those plants and animals that have become so rare they are in danger of becoming extinct. Threatened species are plants and animals that are likely to become endangered within the foreseeable future throughout all or a significant portion of their ranges. Under the Endangered Species Act (ESA), all federal agencies are required to ensure that their regulatory actions are not likely to jeopardize the continued existence of threatened or endangered species or destroy or adversely modify their critical habitat. The ESA is administered by the Interior Department's Fish and Wildlife Service (FWS) and Commerce Department's National Oceanic and Atmospheric Administration (NOAA) Fisheries, depending on the species. EPA's general process for assessing risks to threatened and endangered species and their habitats includes a formal consultation with the FWS and NOAA’s National Marine Fisheries Service. Species may be protected under other Federal laws such as the Migratory Bird Treaty Act and Marine Mammal Protection Act. Additional species of special concern can be designated at the state level.

Other species of concern that might be considered in an ERA include keystone species—species whose presence dramatically alters the structure and dynamics of ecological systems—and susceptible species. Ecological receptors are considered susceptible when they are sensitive to a stressor to which they are or may be exposed. For example, a mammal such as a mink could be selected as a receptor for a bioaccumulative stressorAny physical, chemical, or biological entity that can induce an adverse response (synonymous with agent) that has an increase in concentration in the biological organism over time. such as polychlorinated biphenyls (PCBs), since mink is documented to be sensitive to the bioaccumulation of PCBs.

Endangered Species Websites
U.S. Federal Agency Websites
U.S. State Websites The following links exit the site
U.S. EPAProtecting Endangered Species from Pesticides
U.S. Fish and WildlifeEndangered Species
National Marine Fisheries ServiceEndangered Species Conservation
AlabamaAlabama's Endangered and Threatened Species
AlaskaAlaska's List of Special Status Species
ArizonaArizona's Threatened and Endangered Species Conservation
Arizona's Nongame and Endangered Wildlife Program
ArkansasArkansas' Endangered Species
CaliforniaCalifornia's Threatened and Endangered Species
ColoradoColorado's Threatened and Endangered List
ConnecticutConnecticut's Endangered, Threatened and Special Concerns
DelawareDelaware's Endangered Species
FloridaFlorida's Imperiled Species
Florida's Federally Listed Plant Species
GeorgiaGeorgia Rare Species and Natural Community Data
HawaiiHawaii Invasive Species Council
IdahoIdaho's Threatened, Endangered, and Candidate Species
IllinoisIllinois Dept of Natural Res Div of Natural Heritage Endangered and Threatened Species
IndianaIndiana's Endangered Plant and Animal Species
IowaIowa's Threatened and Endangered Species Program
KansasKansas' Threatened and Endangered Species
KentuckyKentucky's Threatened and Endangered Species
LouisianaLouisiana's Threatened and Endangered Species
MaineMaine's List of Rare Plants
Maine's List of Rare Animals
MarylandMaryland's Rare, Threatened & Endangered Animals
MassachusettsMassachusetts List of Endangered, Threatened and Special Concern Species
MichiganMichigan's Threatened and Endangered Species
MinnesotaMinnesota's Endangered, Threatened, and Special Concern Species
MississippiMississippi's List of Endangered Species
MissouriMissouri's List of Endangered Species
MontanaMontana's Species Conservation and Management
Species Status Codes
NebraskaNebraska's Threatened & Endangered Species
Endangered Species Protection
NevadaNevada's Natural Heritage Species Info
New HampshireNew Hampshire's Nongame and Endangered Species
New JerseyNew Jersey's Endangered and Threatened Wildlife
Wildlife Species of Special Concern in New Jersey
New MexicoNew Mexico's Threatened & Endangered Species
New YorkNew York's Endangered Species
North CarolinaNorth Carolina's Species List
North DakotaNorth Dakota's Threatened and Endangered Species
Endangered Species Protection
OhioOhio's State Listed Wildlife Species
OklahomaOklahoma's Threatened and Endangered Species
OregonOregon's Threatened, Endangered, and Candidate Fish and Wildlife Species
PennsylvaniaPennsylvania's Threatened and Endangered Species
Pennsylvania Listed Plants
Rhode IslandRhode Island Wildlife Action Plan with Species and Habitat Profiles
South CarolinaSouth Carolina's Rare, Threatened & Endangered Species Inventory
South DakotaSouth Dakota's Threatened and Endangered Species
TennesseeTennessee's Endangered or Threatened Species
TexasTexas Nongame and Rare Species Program
Rare, Threatened, and Endangered Species of Texas by County (Interactive Map)
UtahUtah's Endangered and Threatened Animals of Utah
Utah's Conservation Data Center: Reports and Lists
VermontVermont's Endangered and Threatened Species
VirginiaVirginia's Endangered Species
WashingtonWashington's List of Species of Concern
West VirginiaWest Virginia's Rare, Threatened and Endangered Species
WisconsinWisconsin's Endangered and Threatened Species List
WyomingWyoming's Species of Concern

Tools

Information and data sources are available to assist with identifying potential threatened and endangered species to use as receptors in an ERA. Please note that many resources from private organizations also provide species lists, but are not included in the tool table below. The resources compiled here are generally limited to freely available resources from U.S. state and federal sources.

In addition to the tools shown below, there are many available sources of information and data related to the fate and transport of contaminants in environmental media and the transfer of contaminants from an environmental medium to receptor. See the Chemical module of the Stressors Tool Set for information and tools on fate and transport related to chemical stressors.

See the Food Chains and Webs module of the Exposure Pathways (Media) Tool Set for information, data sources, and modeling tools available to help in the evaluation of food chain and food web contaminant transfers in an ERA.

 

EPA EcoBox

  • Basic Information
  • Phases of ERA
    • Planning and Problem Formulation
    • Analysis
    • Risk Characterization
    • Tools
  • Stressors
    • Stressors in ERA
    • Chemical
    • Biological
    • Physical
  • Receptors
    • Receptors in ERA
    • Biota
    • Endangered Species
    • Habitats and Ecosystems
  • Exposure Pathways
    • Exposure Pathways in ERA
    • Air
    • Soil
    • Water and Sediment
    • Food Chains
  • Exposure Factors
  • Effects
    • Effects in ERA
    • Aquatic
    • Terrestrial
  • Toolbox Search
Contact Us about EcoBox
Contact Us about EcoBox to ask a question, provide feedback, or report a problem.
Last updated on July 14, 2025
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