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Sand-verbena Moth (Copablepharon Fuscum)

Technical Summary

Copablepharon fuscum

Sand Verbena Moth

Noctuelle de l'abronie des dunes

Range of Occurrence in Canada: Georgia Basin region, southwestern British Columbia

Extent and Area Information

Extent of occurrence (EO) (km2)3700 km2 in Canada,
4850 km2 globally
Specify trend in EOUnknown; likely stable
Are there extreme fluctuations in EO?No
Area of occupancy (AO) (km2)+/- 5 km2 in Canada
<25 km2 globally
Specify trend in AOUnknown; likely declining
Are there extreme fluctuations in AO?No
Number of known or inferred current locations3 in Canada; 8 globally
Specify trend in #Unknown; stable in short-term; declining in long-term?
Are there extreme fluctuations in number  of locations?No
Specify trend in area, extent or quality of habitatDeclining

Population Information

Generation time
(average age of parents in the population)
1 year
Number of mature individualsUnknown (range of 350 to 10 500 based on a range of 0.2 to 6.0 moths/m2 of A. latifolia)
Total population trendUnknown but likely declining
% decline over the last/next 10 years or 3 generationsUnknown
Are there extreme fluctuations in number of mature individuals?Unknown but likely yes (based on other insects)
Is the total population severely fragmented?Yes
Specify trend in number of populationsUnknown; stable in short-term; declining in long-term
Are there extreme fluctuations in number  of populations?No
List populations with number of mature individuals in each:Near Comox, B.C. Pop 1
Near Comox, B.C. Pop 2
Near Sidney, B.C. Pop 3
Number of mature individuals unknown.

Threats (actual or imminent threats to populations or habitats)

-  reduction in quantity and quality of host-plant resources from stabilization or degradation of open sand habitat. This includes exotic plant species colonization, recreation disturbance, development of roads, buildings, etc., and changes to sand supply or transport. The risk of disease, predation, or other biotic threats to either C. fuscum or A. latifolia is unknown.
-  potential threats include pesticide use in or adjacent to population sites and loss of habitat from sea-level increases associated with climate change.
-  collecting or other forms of direct human-caused mortality are considered low.

Rescue Effect (immigration from an outside source): Low

Status of outside population(s)?
USA:  Unknown; likely declining
Is immigration known or possible?Possible, but very unlikely
Would immigrants be adapted to survive in Canada?Yes
Is there sufficient habitat for immigrants in Canada?Unknown
Is rescue from outside populations likely?Highly unlikely

Quantitative Analysis

Not undertaken because of lack of data

Author: N.A. Page, May 2003
Sources of information: status report

Current Status

COSEWIC: No previous COSEWIC designation

Status and Reason for Designation

Alpha-numeric code:
B1ab(ii,iii,iv,v) +2ab(ii,iii,iv,v)
Reason for designation:
The global population of this moth is very small and occurs in a very restricted range. The Canadian population, occurring at only three small sites, is even smaller and more restricted. The moth and its host-plant are habitat specialists dependent on coastal dunes, a rare habitat along the West Coast. This habitat has undergone extensive losses due to stabilization of open dunes (including the introduction of invasive plant species), development and recreational use. The host-plant and therefore the moth are facing the threat of continuing declines due to the loss and degradation of coastal dunes.

Applicability of Criteria

Criterion A (Declining Total Population):
- cannot be applied as there have not been any previous population estimates and so it is not possible to quantify declines.
Criterion B (Small Distribution, and Decline or Fluctuation):
- the EO is <5000 km2 (B1);
- the AO is << 500 km2 (B2);
- the population is severely fragmented and is known to exist at 3 sites between which there is believed to be no, or very little, genetic exchange (a);
- there is evidence for continuing declines in area and quality of habitat, number of locations and number of mature individuals – all related to loss/degradation of the larval hostplant and its habitat (b)(ii - v);
- the population likely undergoes extreme fluctuations in numbers of mature individuals (c)(iv), but there is no hard evidence for this.
Criterion C (Small Total Population Size and Decline):
- the number of mature individuals is <10 000;
- there is no quantitative information enabling a calculation of decline rate;
- a continuing decline in the number of mature individuals is inferred because of continuing habitat degradation (C2);
- population fragmentation exists and no population consists of >1000 mature individuals (a)(i);
- and extreme fluctuations in the number of mature individuals are suspected (b).
Criterion D (Very Small Population or Restricted Distribution):
- the total number of mature individuals in likely >1 000
- the AO is <20 km2 and the species occurs at <5 locations (D2).
Criterion E (Quantitative Analysis):
- the available information is insufficient to do a quantitative analysis of the probability of extinction.