• LE: Listed endangered - Any species in danger of extinction throughout all or a significant portion of its range (16 U.S.C. 1532(6)).
• PE: Proposed endangered - Any species for which a proposed rule has been published in the Federal Register to list the species as endangered.
• LT: Listed threatened - Any species likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range (16 U.S.C. 1532(20)).
• PT: Proposed threatened - Any species for which a proposed rule has been published in the Federal Register to list the species as threatened.
• E(S/A) or T(S/A): Any species listed endangered or threatened because of similarity of appearance.
• C: Candidate - Those taxa for which sufficient information on biological status and threats exists to propose to list them as threatened or endangered. We encourage their consideration in environmental planning and partnerships; however, none of the substantive or procedural provisions of the Act apply to candidate species.
• PDL: Proposed for delisting - Any species for which a final rule has been published in the Federal Register to delist the species.
• DM: Delisted Taxon, recovered, being monitored for first five years.
• NL: Not listed - No designation.
• XE: Essential experimental population - An experimental population whose loss would be likely to appreciably reduce the likelihood of the survival of the species in the wild.
• XN: Nonessential experimental population - An experimental population of a listed species reintroduced into a specific area that receives more flexible management under the Act.
• CH: Critical Habitat - The specific areas (i) within the geographic area occupied by a species, at the time it is listed, on which are found those physical or biological features (I) essential to conserve the species and (II) that may require special management considerations or protection; and (ii) specific areas outside the geographic area occupied by the species at the time it is listed upon determination that such areas are essential to conserve the species.
• PS: Partial status - status in only a portion of the species’ range. Typically indicated in a “full” species record where an infraspecific taxon or population, that has a record in the database has USESA status, but the entire species does not.
• PS:value: Partial status - status in only a portion of the species’ range. The value of that status appears in parentheses because the entity with status is not recognized as a valid taxon by Central Sciences (usually a population defined by geopolitical boundaries or defined administratively, such as experimental populations.
• None: Usually indicates the taxon does not have any federal status. However, because of potential lag time between publication in the Federal Register and entry in the central databases and refresh of this website, some taxa may have a status that does not yet appear.

The status of species on Forest Service lands as defined by the U.S. Forest Service manual (2670.22). These taxa are listed as such by the Regional Forester (Northern Region). The Forest Service lists animal species as:

• Endangered: Listed as Endangered (LE) by the USFWS.
• Threatened: Listed as Threatened (LT) by the USFWS.
• Sensitive: Any species for which the Regional Forester has determined there is a concern for population viability within the state, as evidenced by a significant current or predicted downward trend in populations or habitat.
• Watch: Any species recognized by Forest Supervisors that are either not known to occur on national forest land but predicted to occur there on the basis of suitable habitat, or known to occur on national forest land but with no immediate or predicted threats to population viability.

The status of species on Bureau of Land Management Lands as defined by the BLM 6840 Manual; designated by the Montana State Office of the BLM in 1996.

• Special Status / Sensitive: Any species proven to be imperiled in at least part of its range and documented to occur on BLM lands.
• Watch: Any species either known to be imperiled and suspected to occur on BLM lands; suspected to be imperiled and documented on BLM lands; or needing further study for other reasons.