The ESA requires the Secretary of the Interior, who acts through the U.S. Fish and Wildlife Service (Service), to make various decisions about the status and protection of animal and plant species. ESA sections 3(15), 4(a)(2). The Service administers the following core programs in that regard:
- Section 4 authorizes the Service to identify "endangered" and "threatened" species, known as the "listing" function, and then to designate "critical habitat" and develop "recovery plans" for the species.
- Section 7 requires all federal agencies to ensure that actions they carry out, fund, or authorize do not "jeopardize" the continued existence of listed species or "adversely modify" their critical habitat.
- Section 9 requires that all persons, including all private and public entities subject to federal jurisdiction, avoid committing "take" of listed species of fish and wildlife.
- Sections 7 (for federal actions) and 10 (for actions not subject to Section 7) establish a procedure and criteria for the Service to approve "incidental take" of listed species.
The central prohibitory ESA provision is section 9, that prohibits the "take" of a listed species. By regulation, the Service has defined take to include habitat destruction or modification that actually results in death or injury to a member of the species. Private landowners, and state or local governments who want to conduct activities on their land that might incidentally "take" a species listed as endangered or threatened under the ESA may obtain an incidental take permit (also commonly referred to as a "10(a) permit") from the Service prior to conducting such activities. To obtain a permit, the applicant must develop a habitat conservation plan (HCP) that is designed to minimize and mitigate the impacts of the taking sought to be authorized. The HCP process allows activities to proceed while promoting the conservation of listed species.