Stoloniferous pussytoes (Antennaria flagellaris) COSEWIC assessment and status report: chapter 11

Technical Summary

Antennaria flagellaris

stoloniferous pussytoes – antennaire stolonifère

Range of Occurrence in Canada:
British Columbia

Extent and Area Information

Extent of occurrence (EO) (km²) (along 3.2 km of highway) :
4.8 km²
Specify trend in EO :
Unknown, probably stable
Are there extreme fluctuations in EO?
Unknown since no losses or re-discoveries of sites have been documented
Area of occupancy (AO) (km²) (area of 3 habitats occupied)
<<1  km² (0.22 ha)
Specify trend in AO :
Unknown, probably stable, but might fluctuate depending on groundwater hydrological changes with precipitation patterns
Are there extreme fluctuations in AO?
Unknown but some fluctuations in area may occur due to annual fluctuations in climatic conditions and site hydrological regime
Number of known or inferred current locations :
3
Specify trend in # :
Unknown, probably stable
Are there extreme fluctuations in number of locations?
Unknown but perhaps some fluctuation is possible due to annual fluctuations in climatic conditions and site hydrological regime
Specify trend in area, extent or quality of habitat :
Unknown, probably stable

Population Information

Generation time (average age of parents in the population) :
Unknown, possibly 3 years
Number of mature individuals :
ca. 1,400,000 +/- 100,000
Total population trend:
Inferred decline based on potential developments in the region such as coalbed methane production
 % decline over the last/next 10 years or 3 generations.
Not applicable
Are there extreme fluctuations in number of mature individuals?
Unknown but perhaps possible under severe conditions of drought
Is the total population severely fragmented?
No
Specify trend in number of populations :
Unknown, probably stable
Are there extreme fluctuations in number of populations?
Unknown and unlikely considering the few sites known and no evidence of changes based on site hydrological regime fluctuations
List populations with number of mature individuals in each:
1) 5000;
2) 400-500;
3) 1,400,000 +/- 100,000

Threats (actual or imminent threats to populations or habitats)

  • off-road vehicle use
  • weed control activities on power line just north of site
  • potential change in water table level with increasing population base and potential coalbed methane production

Rescue Effect (immigration from an outside source)

Status of outside population(s)?
USA: S1 in Wyoming, and S3.2 in California. It is unranked in Washington, Oregon and Idaho.
Is immigration known or possible?
Unknown
Would immigrants be adapted to survive in Canada?
Unknown
Is there sufficient habitat for immigrants in Canada?
Unlikely
Is rescue from outside populations likely? (Distance to nearest population in Washington State is about 190 km and habitats are very small.) :
Unlikely

Quantitative Analysis

Not Applicable

Other Status

Status and Reasons for Designation

Status:  Endangered

Alpha-numeric code: B1ab(ii,iii,v)+2ab(ii,iii,v)

Reasons for Designation: A short-lived perennial plant present at only three geographically restricted localities occupying very small areas of specialized habitat of ephemerally moist seepage sites on private lands. It is at greatest risk from ATV use that currently is evident in close proximity to the populations.It may also be impacted by changes in ground water hydrology and surface impacts from increased development activities in the area such as the proposed production of coalbed methane.

Applicability of Criteria

Criterion A (Declining Total Population): Not applicable: No declines documented

Criterion B (Small Distribution, and Decline or Fluctuation): Endangered under B1 and B2 (a and b, ii, iii, v) due to the small distribution with an extent of occurrence of <5 km² and small area of occupancy of << 1 km² (0.22 ha) and only known from 3 localities; threats of loss of area of occupancy, change in quality of habitat and reduction in number of individuals from ATV use are very real and of imminent occurrence; impacts from chemical weed control of nearby hydro right-of-way are a potential threat, as is the change in water table due to increased housing development. 

Criterion C (Small Total Population Size and Decline): Not applicable: Large population and no declines documented.

Criterion D (Very Small Population or Restricted Distribution):Threatened under D2 with a small area of occupancy (<20 km² ) and < 5 locations.

Criterion E (Quantitative Analysis): Not applicable.

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