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COSEWIC Assessment and Update Status Report on the Bering Cisco in Canada

Technical Summary

Coregonus laurettae

Bering Cisco
Cisco du Bering

Range of Occurrence in Canada: Yukon Territory

Extent and Area Information

Extent of occurrence (EO)
[estimated from Figure 2]

<1000 km2

Trend in EO


Are there extreme fluctuations in EO?


Area of occupancy AO
[estimated from Figure 2, the river is nowhere more than 1 km wide]

<1000 km2

Trend in AO


Are there extreme fluctuations in AO?


Number of known or inferred current locations (see Figure 2)


Trend in # locations


Are there extreme fluctuations in # locations?


In area, extent or quality of habitat?

Unknown, but probably Stable

Population Information

Generation time (average age of parents in the population)

4-6 yr

Number of mature individuals


Total population trend


% decline over the last/next 10 years or 3 generations


Are there extreme fluctuations in number of mature individuals?


Is the total population severely fragmented?


Trend in number of populations


Are there extreme fluctuations in number of populations?


List populations with number of mature individuals in each

Not Applicable

Threats (actual or imminent threats to populations or habitats)

  • low to moderate, possibility of increased oil development and habitat alterations in coastal regions throughout its range
  • potential for hydroelectric development on rivers where they are known to migrate
  • potential for increased commercial utilization
  • possible threats to the species in Canadian waters would be related to harvest and any activities which might restrict migration such as the building of power dams.

Rescue Effect: High

Status of the outside population(s)?

Asia: Unknown
USA: Secure

Is immigration known or possible?

Not known if Canadian migrants are separate stock from US population

Would immigrants be adapted to survive in Canada?


Is there sufficient habitat for immigrants here?


Quantitative Analysis

Not Applicable

Existing Status

Nature Conservancy Ranks

Global – N4


US – N4
Canada – N1


US – Alaska – S?
Canada – Yukon S?

COSEWIC – Data Deficient, 1990

Status and Reasons for Designation

Status: Special Concern

Alpha-numeric code: Not applicable

Reasons for Designation: This is an anadromous species that depends on barrier-free access to upstream spawning sites. In Canada, it is known only from the Yukon River. The numbers utilizing Canadian portions of the Yukon River are low compared to lower sections of the river in United States parts of the range and could be negatively impacted by hydroelectric development and expansion of commercial or subsistence fisheries, targeting other species in the river.

Applicability of Criteria

Criterion A (Declining Total Population):
Not applicable, no evidence of population decline.

Criterion B (Small Distribution, and Decline or Fluctuation):
Not applicable, although the species has a small Canadian distribution, its extent and nature of the range is uncertain, and there is no evidence of decline or fluctuation.

Criterion C (Small Total Population Size and Decline):
Not applicable, population size and trends not known. Numbers counted annually since the 1980s have been low, but counting is not consistent and the species may be easily confused with other sympatric coregonids.

Criterion D (Very Small Population or Restricted Distribution):
Not applicable. Although the species does meet the numeric thresholds under Threatened D2, i.e., restricted distribution, known only from 1 location. However, there are no immediate threats exposing the species to imminent extirpation and there is a high potential for rescue from U.S. populations.

Criterion E (Quantitative Analysis):
Not applicable, - no data.