COSEWIC: NatureServe Explorer Data for Assigned Status in Canada

COSEWIC: NatureServe Explorer Data for Assigned Status in Canada

Legal Status of Canadian Species

Since 1977 the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) ( has been providing advice to the Canadian federal government on the status of wildlife species. With the passage of the landmark Species at Risk Act (SARA) in 2003 (, the Government of Canada will now take COSEWIC status into consideration when establishing the legal list of species at risk. Species that were designated at risk by COSEWIC prior to October 1999 must be reassessed using revised criteria before they can be considered for addition to the list of species at risk. Under SARA, the listing process begins with a species assessment that is conducted by COSEWIC. Upon receiving an assessment, the Governor in Council may on the recommendation of the Minister, amend the List and add a wildlife species; reclassify a listed wildlife species; or remove a listed wildlife species. When the Governor in Council has not taken a course of action within nine months of receiving the assessment, the Minister shall amend the List in accordance with COSEWIC's assessment. Once listed, the measures to protect and recover a listed wildlife species are implemented.

COSEWIC is composed of qualified wildlife experts drawn from the federal, provincial, and territorial governments, wildlife management boards, Aboriginal groups, universities, museums, national non-governmental organizations and others with expertise in the conservation of wildlife species in Canada. The role of COSEWIC is to assess and classify the status of wildlife species using the best available information on the biological status of a species, including scientific knowledge, community knowledge, and Aboriginal traditional knowledge. Specifically, COSEWIC determines the national status of wild Canadian species, subspecies and separate populations suspected of being at risk. The current mandate includes all native mammals, birds, reptiles, amphibians, fish, molluscs, arthropods, lepidopterans (butterflies and moths), vascular plants, mosses and lichens. COSEWIC holds meetings biannually to review status reports prepared for each species under consideration for official status. The Committee reviews the situation of each species and assigns status to each species under review. Updated status reports that re-examine pertinent information may result in a species' status being confirmed, upgraded to a more serious risk category, or downgraded to a less serious risk category, or the species may be removed from the list. COSEWIC assessments and the reasons for the speciesí status are posted on the SARA Public Registry ( COSEWIC also provides a summary of all assessments as a Canadian Species at Risk list (

NatureServe staff regularly update all species records affected in the central databases to account for all changes and additions to the COSEWIC status and SARA designations. The date the species' COSEWIC status was assigned (the most recent status assignment or confirmation) accompanies each record. NatureServe Explorer is updated periodically from the NatureServe central databases and reflects the status current at the time of update.

Definitions of COSEWIC Status and SARA Designation in NatureServe Explorer

For most species that have COSEWIC or SARA status, any available distribution, conservation, and management information is maintained in records under the same scientific name as the one used in the Canadian Species at Risk list. For some subspecies and populations that have COSEWIC status, most of this information is maintained in the species record associated with the subspecies or population. Where the names used by COSEWIC and NatureServe differ, data in NatureServe Explorer can be found using either name.

COSEWIC Status Abbreviations
NatureServe Explorer



A wildlife species that no longer exists.



A wildlife species no longer existing in the wild in Canada, but occurring elsewhere.



A wildlife species facing imminent extirpation or extinction.



A wildlife species likely to become endangered if limiting factors are not reversed.


Special Concern1

A wildlife species that may become a threatened or an endangered species because of a combination of biological characteristics and identified threats.


Not At Risk

A wildlife species that has been evaluated and found to be not at risk of extinction given the current circumstances.


Data Deficient

A category that applies when the available information is insufficient: a) to resolve a wildlife speciesí eligibility for assessment; or b) to permit an assessment of the wildlife speciesí risk of extinction.

C Candidate

A wildlife species that is not yet assessed by COSEWIC but has been identified by the Species Specialist Subcommittees (SSCs) or by the Aboriginal Traditional Knowledge (ATK) Subcommittee as a potential species needing a detailed status assessment.


Null value

A wildlife species that does not have any COSEWIC status, has not been evaluated by COSEWIC, or its status does not yet appear on NatureServe Explorer because of the possible lag time between the NatureServe central databases and the refresh of the data on the website.

1Status used in the SARA designations

Status Due to Taxonomic Relationship (Implied COSEWIC status)

The taxonomic relationships between species and their infraspecific taxa may determine whether a taxon has COSEWIC status. The assignment of status to a taxon includes lower taxonomic units that occur in Canada. Also, if an infraspecific taxon or population has COSEWIC status, then by default, some part of the species also has status. NatureServe Explorer data for some taxa show values indicating COSEWIC status, even though the taxonomic entity may not be specifically named in the Canadian Species at Risk list. Where status is implied due to a taxonomic relationship alone, the status abbreviation appears with a flag (2).

Status of Geopolitically or Administratively Defined Populations

COSEWIC status has been assigned to some populations that are defined by geopolitical boundaries within Canada (i.e., the status applies to the species or subspecies within those boundaries, even though it may range more broadly). Although most of these populations do have individual records in NatureServe Explorer, for clarity, the COSEWIC status is recorded for the species or subspecies to which that population belongs. In these cases, the status abbreviation appears with a flag (5), after the abbreviation "PS" for "partial status" - indicating that the status applies only to a portion of the species' range.

Implied COSEWIC Status Notations (Status Due to Taxonomic Relationship)
Example Explanation Definition


Flagged Values

The taxon itself is not named in the Canadian Species at Risk list, however, it does have status as a result of its taxonomic relationship to a named entity. For example, if a species has a COSEWIC status of "threatened," then by default, all of its recognized subspecies that occur in Canada also have threatened status. The subspecies in this example would have the value "T(2)" under COSEWIC. Likewise, if all of a species' infraspecific taxa occurring in Canada have the same COSEWIC status, then that status appears in the entry for the "full" species as well. In this case, if the species name is not mentioned in the Canadian Species at Risk list, the status appears with a flag (2) in NatureServe Explorer.


Combination values with flags

The taxon itself is not named in the Canadian Species at Risk list, however, all of its infraspecific taxa occurring in Canada do have status but two or more of the taxa do not have the same status. In this case, a combination of statuses shown with a flag (7) indicates the statuses that apply to infraspecific taxa or populations within this taxon.


partial status

Indicates "partial status" - status in only a portion of the species' range in Canada. Typically indicated for a "full" species where at least one but not all of a species' infraspecific taxa or populations has COSEWIC status.


partial status

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 within Canada) does not have an individual entry in NatureServe Explorer. Information about the entity with status can be found in reports for the associated species.


Copyright 2018