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Species Status and Rank Definitions

 

Federal Status: US Fish and Wildlife Service (USFWS)

The table below denotes categories defined in the U.S. Fish and Wildlife Service Notice of Review (1980, 1983, 1985, 1990, 1993, 1996) and indicate the status of a taxon under the federal Endangered Species Act of 1973 (16 U.S.C.A. § 1531-1543 (Supp. 1996).

See https://ipac.ecosphere.fws.gov/status/list for more information.

The Endangered Species Act defines endangered and threatened as the following:
"The term 'endangered species' means any species which is in danger of extinction throughout all or a significant portion of its range other than a species of the Class Insecta determined by the Secretary to constitute a pest whose protection under the provisions of this chapter would present an overwhelming and overriding risk to man."

"The term 'threatened species' means any species which is likely to become an endangered species within the foreseeable future throughout all or a significant portion of its range."

BASIC FEDERAL STATUS DESIGNATIONS

LE = Listed Endangered
Species for which a final rule has been published in the Federal Register to list the species as endangered. Species is legally protected by the Endangered Species Act.

LT = Listed Threatened
Species for which a final rule has been published in the Federal Register to list the species as threatened. Species is legally protected by the Endangered Species Act.

PE = Proposed Endangered
Species for which a proposed rule has been published in the Federal Register to list the species as endangered

PT = Proposed Threatened
Species for which a proposed rule has been published in the Federal Register to list the species as threatened.

PS = Partial Status
Species has status in only a portion of the species' range. Typically indicated in a "full" species record where an infraspecific taxon or population has Federal status, but the entire species does not.

C or CN = Candidate for Listing
Substantial information exists in U.S. Fish and Wildlife Service files on biological vulnerability to support proposals to list as endangered or threatened.

SC = Species of Concern
The terms "Species of Concern" or "Species at Risk" should be considered as terms-of-art that describe the entire realm of taxa whose conservation status may be of concern to the US Fish and Wildlife Service, but neither term has official status (currently all former C2 species).

PDL = Proposal for delisting
Species for which a proposal for delisting has been published in the Federal Register.

DL = Delisted
Species for which a final rule has been published in the Federal Register to delist the species.

XN = Non-essential Experimental Population
Species for which a population has been artificially established in the wild which is not essential to the survival of the species in the wild.

T(S/A) = Listed as Threatened Due to Similarity of Appearance
Species listed as threatened due to similarity of appearance with another species this is listed as threatened.

Note:
The categories C2, and subcategories 3B and 3C are no longer maintained by the USFWS (61 FR 7596, Feb. 28, 1996).

MORE COMPLICATED FEDERAL STATUS DESIGNATIONS

The taxonomic relationships between species and their infraspecific taxa may determine whether a taxon has federal protection. Section 17.11(g) of the Endangered Species Act states, "the listing of a particular taxon includes all lower taxonomic units." Also, if an infraspecific taxon or population has federal status, then by default, some part of the species has federal protection. Our data for some taxa show values indicating Federal status even though the element may not be specifically named in the Federal Register. Where status is implied due to a taxonomic relationship alone, the status abbreviation appears in parentheses.

Federal status has been assigned to some vertebrate populations which are defined by geopolitical boundaries (i.e., the status applies to the element only within those boundaries, even though the range of the element may extend beyond the boundaries), or to populations which are administratively defined (e.g., experimental populations). Since these populations do not have individual entries in our database, the Federal status is recorded for the species or subspecies to which that population belongs. In these cases, the status abbreviation appears in parentheses, after the abbreviation "PS" for "partial status" - indicating that the status applies only to a portion of the species' range.

Value, Value
The taxon has one status currently, but a more recent proposal has been made to change that status with no final action yet published. For example, "LE, PDL" indicates that the species is currently listed as endangered, but has been proposed for delisting.

(Value)
The taxon itself is not named in the Federal Register as having Federal status; however, it does have Federal status as a result of its taxonomic relationship to a named entity. For example, if a species is federally listed with endangered status, then by default, all of its recognized subspecies also have endangered status. The subspecies in this example would have the value "(LE)" under Federal Status. Likewise, if all of a species' infraspecific taxa (worldwide) have the same Federal status, then that status appears in the record for the "full" species as well. In this case, if the taxon at the species level is not mentioned in the Federal Register, the status appears in parentheses in that record.

(Value, Value)
The taxon itself is not named in the Federal Register as having Federal status; however, all of its infraspecific taxa (worldwide) do have official status. The statuses shown in parentheses indicate the statuses that apply to infraspecific taxa or populations within this taxon.

(PS)
Indicates "partial status" - status in only a portion of the species' range. Typically indicated in a "full" species record where an infraspecific taxon or population has Federal status, but the entire species does not.

(PS; Value)
Indicates "partial status" - status in only a portion of the species' range. The value of that status appears because the entity with status (usually a population defined by geopolitical boundaries or defined administratively, such as experimental populations) does not have an individual entry in NM.

State Status: State of New Mexico

 

Endangered - Any species or subspecies whose prospects of survival or recruitment in New Mexico are in jeopardy.

Threatened - Any species or subspecies that is likely to become endangered within the foreseeable future throughout all or a significant portion of its range in New Mexico.

Source: New Mexico Administrative Code, Title 19, Chapter 33 Part 6.7

State Rank: Natural Heritage New Mexico

The State Rank reflects the conservation status of a species from a local perspective, characterizing the relative rarity or imperilment of the species within the state of New Mexico. The status of an element is indicated on a scale of one to five; the score is based on the estimated number of extant occurrences of the element and other factors such as trends, threats and abundance.

Note: This is a list of the most commonly encountered ranks. For additional ranks, please NatureServe's webpage on Conservation Status Ranks located here.

BASIC STATE RANKS

Rank definitions are determined by NatureServe.

SX = Presumed Extirpated 
Believed to be extirpated. Not located despite intensive searches and virtually no likelihood that it will be rediscovered.

SH = Possibly Extirpated
Known only from historical occurrences. Still some hope of rediscovery.

S1 = Critically Imperiled 
Critically imperiled in the state because of extreme rarity or because of some factor(s) making it especially vulnerable to extirpation. Typically 5 or fewer occurrences or very few remaining individuals (<1,000).

S2 = Imperiled
Imperiled in the state because of extreme rarity or because of some factor(s) making it especially vulnerable to extirpation. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000).

S3 = Vulnerable
Vulnerable in the state either because very rare and local throughout its range, found only in a restricted range (even if abundant at some locations) , or because of other factors making it vulnerable to extirpation. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals

S4 = Apparently Secure
Uncommon but not rare, and usually widespread. Possibly cause for long­term concern. Typically more than 100 occurrences in the state or more than 10,000 individuals.

S5 = Secure
Common, typically widespread and abundant.

VARIANT STATE RANKS

S#S# = Range Rank
A numeric range rank (e.g., S2S3) is used to indicate uncertainty about the exact status of a taxon.

SA = Accidental
Accidental or casual in NM. In other words, infrequent and outside usual range. Includes species (usually birds or butterflies) recorded once or only a few times at a location.

SE = Exotic
An exotic established in state; may be native elsewhere in North America; includes fish native to NM but introduced into watersheds where the species is non-native. An exotic established in NM may be assigned a numeric rank (e.g. SE2) to indicate its status, as defined for S1 through S5.

SU = Unrankable
Currently unrankable due to lack of available information about status or trends.

HYB = Hybrid

SRF = False Report
Element reported in NM but the report is known to be invalid.

SNR = Not Ranked
State conservation status not yet assessed.

S? = Unranked
Rank not yet assessed.

RANK QUALIFIERS

? = Inexact numeric rank
Denotes inexact numeric rank.

Q = Questionable taxonomy 
Taxonomic status is questionable; numeric rank may change with taxonomy.

C = Captive or cultivated only
Taxon at present is extant only in captivity or cultivation, or as a reintroduced population not yet established.

B = Breeding
The associated rank refers to breeding occurrences of mobile animals.

N = Non-breeding
The associated rank refers to non-breeding occurrences of mobile animals.

M = Migrant
The associated rank refers to the aggregating transient population of the species in New Mexico. Used for migrant species occurring regularly on migration at particular staging areas or concentration spots where the species might warrant conservation attention.

Z = Moving
Occurs in the state, but as a diffuse, usually moving population; difficult or impossible to map static occurrences.

Note: A breeding status is only used for species that have distinct breeding and/or non-breeding populations in the nation or state/province. A breeding-status S-rank can be coupled with its complementary non-breeding-status S-rank if the species also winters in the state. In addition, a breeding-status S-rank can also be coupled with a migrant-status S-rank if, on migration, the species occurs regularly at particular staging areas or concentration spots where it might warrant conservation attention. Multiple conservation status ranks (typically two, or rarely three) are separated by commas (e.g., S2B,S3N or SHN,S4B,S1M).

INFRASPECIFIC TAXON RANKS

T = Infraspecific Taxon (trinomial) The status of infraspecific taxa (subspecies or varieties) are indicated by a "T-rank" following the species' state rank. Rules for assigning T ranks follow the same principles outlined above. For example, the state rank of a critically imperiled subspecies of an otherwise widespread and common species would be S5T1.

Global Rank Values
 
The Global (G) Rank reflects the conservation status of a species from a global (i.e. rangewide) perspective, characterizing the relative rarity or imperilment of the species. Global conservation status ranks are based primarily on three factors: the number of occurrences; the total overall abundance of the element; and the overall size of the geographic range. Additional considerations include quality of the occurrences, ecological fragility, threats from human activity, and difficulty in providing appropriate management. For discussion of factors used in determining species status ranks see: L. L. Master. 1991. Assessing threats and setting priorities for conservation. Conservation Biology 5:559-563.
 

Note: This is a list of the most commonly encountered ranks. For additional ranks, please NatureServe's webpage on Conservation Status Ranks located here.

BASIC GLOBAL RANKS

GX = Presumed Extinct
Believed to be extinct throughout its range. Not located despite intensive searches and virtually no likelihood that it will be rediscovered.

GH = Possibly Extinct
Known only from historical occurrences. Still some hope of rediscovery.

G1 = Critically Imperiled
Critically imperiled globally because of extreme rarity or because of some factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000).

G2 = Imperiled
Imperiled globally because of extreme rarity or because of some factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000).

G3 = Vulnerable
Vulnerable globally either because very rare and local throughout its range, found only in a restricted range (even if abundant at some locations) , or because of other factors making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals

G4 = Apparently Secure
Uncommon but not rare, and usually widespread. Possibly cause for long­term concern. Typically more than 100 occurrences globally or more than 10,000 individuals.

G5 = Secure
Common, typically widespread and abundant.

VARIANT GLOBAL RANKS

G#G# = Range Rank
A numeric range rank (e.g., G2G3) is used to indicate uncertainty about the exact status of a taxon.

GU = Unrankable
Currently unrankable due to lack of available information about status or trends.

G? = Unranked
Global rank not yet assessed.

HYB = Hybrid

RANK QUALIFIERS

? = Inexact numeric rank
Denotes inexact numeric rank.

Q = Questionable taxonomy
Taxonomic status is questionable; numeric rank may change with taxonomy.

C = Captive or cultivated only
Taxon at present is extant only in captivity or cultivation, or as a reintroduced population not yet established.

Z = Moving
Occurs as a diffuse, usually moving population; difficult or impossible to map static occurrences.

INFRASPECIFIC TAXON RANKS

T = Infraspecific Taxon (trinomial)
The status of infraspecific taxa (subspecies or varieties) are indicated by a "T-rank" following the species' global rank. Rules for assigning T ranks follow the same principles outlined above. For example, the global rank of a critically imperiled subspecies of an otherwise widespread and common species would be G5T1.