Endangered Species Act - Categories of Status
Administered by the U. S. Fish and Wildlife Service in Idaho

Listed Species
(50 CFR 17.11 and 17.12)

Listed Endangered (LE). Taxa in danger of Extinction throughout all or a significant portion of their range.
Listed Threatened (LT). Taxa likely to be classified as Endangered within the foreseeable future throughout all or a significant portion of their range.

Proposed and Candidate Species
(Federal Register 64(205): 57534-57547, 1999)

Proposed Endangered (PE). Taxa proposed to be listed as Endangered (formal rulemaking in progress).
Proposed Threatened (PT). Taxa proposed to be listed as Threatened (formal rulemaking in progress).
Candidate (C) species. Taxa for which the USFWS has on file sufficient information on biological vulnerability and threats to support issuance of a proposed rule to list, but issuance of the proposed rule is precluded.

Petitioned (p). Species for which the U. S. Fish and Wildlife Service has received a petition to list as Endangered or Threatened.

Experimental, Nonessential Population
(50 CFR 17.11 and 17.12)

Experimental, nonessential population (XN). Currently applied to two reintroduced species: gray wolf (south of Interstate 90) and whooping crane (Grays Lake).