Which federal agency determines what species are endangered?

The correct answer is the Fish and Wildlife Service (FWS) because this agency is primarily responsible for the conservation, protection, and enhancement of fish, wildlife, and plants, including managing the Endangered Species Act (ESA). Under the ESA, the FWS is tasked with identifying and listing species that are endangered or threatened, thus playing a crucial role in the preservation of biodiversity.

The FWS conducts thorough assessments, evaluating the status of species and their habitats. This process involves scientific research, habitat protection measures, and recovery planning for listed species. The agency collaborates with various stakeholders, including state wildlife agencies, conservation organizations, and the public, to ensure effective implementation of the Act and to promote recovery efforts for endangered species.

Other federal agencies, such as the U.S. Department of Agriculture, may be involved in related agricultural issues or conservation efforts, but they do not have the authority to designate endangered species. The Office of Pesticide Programs (OPP) of the EPA focuses on regulating pesticides and their impacts on human health and the environment, including wildlife, yet it does not determine species at risk. NOAA handles marine species and ecosystems, specifically through its National Marine Fisheries Service, but it does not encompass terrestrial species that the FWS covers.