Vancouver Island COSEWIC assessment and status report: chapter 11
Technical Summary
Marmota vancouverensis
Vancouver Island marmot – Marmotte de l’île de Vancouver
Range of Occurrence in Canada:
Vancouver Island, British Columbia
Demographic Information
Generation time (average age of parents in the population) :
5.28 years (SD: 1.65, n=297 female-years
Population trend and dynamics
Observed percentage of reduction in total number of mature individuals over the last 3 generations :
Excluding reintroductions, 80%
Projected percentage of reduction in total number of mature individuals over the next 10 years.
Excluding reintroductions, a life-table analysis suggests a lambda of 0.89 (Appendix 1)
Observed percentage reduction in total number of mature individuals over any 10 years period, over a time period including both the past and the future.
Unknown
Are the causes of the decline clearly reversible?
No
Are the causes of the decline clearly understood?
No
Are the causes of the decline clearly ceased?
No
Observed trend in number of populations :
Decline - From >35 to 5 in 25 years
Are there extreme fluctuations in number of mature individuals?
No
Are there extreme fluctuations in number of populations?
No
Number of mature individuals in each population (Autumn 2007)
- Mount Moriarty: 6 expected =6 alive on 30 April (1 emerged)
- Green Moutain: 4 expected, minimum=2 alive on 30 April
- Gemini Peak: 5 expected, minimum=2 alive on 30 April
- Bell Creek: 5 expected, minimum=5 alive on 2 May (3 emerged)
- Haley Bowl: 5 expected, minimum=5 alive on 30 April (5 emerged)
- Butler Peak: 5 expected, minimum=4 alive on 4 May
- Big Ugly: 2 expected, minimum=2 alive on 30 April
- Heather Moutain: 2 expected, minimum=1 alive on 30 April
- Mount Hooper: 1 expected, minimum=1 alive on 30 April
- Mount Washington: 11 expected, minimum=10 alive on 4 May (2 emerged)
- Total: About 25-30 wild-born adults, plus captive-bred ones
- Grand Total: About 25-30 wild-born
Extent and Area Information
Estimated extent of occurrence (km²) :
170 km²
Observed trend in extent of occurrence :
Increasing through reintroductions
Are there extreme fluctuations in extent of occurrence?
No
Estimated area of occupancy (km²) :
22 km²
Observed trend in area of occupancy :
Increasing through reintroductions
Are there extreme fluctuations in area of occupancy?
No
Is the total population severely fragmented?
No
Number of current locations :
10
Trend in number of locations :
Increasing through reintroductions
Are there extreme fluctuations in number of locations?
No
Observed trend in area of habitat :
Stable
Quantitative Analysis
[0.00% probability of extirpation in years]
Threats (actual or imminent, to populations or habitats)
Predation, possibly inbreeding
Rescue Effect (immigration from an outside source)
Status of outside population(s)?
Canadian endemic. There is an active captive breeding program, presently n > 140, lambda: 1.31, 30-50 releasable marmots per year.
Is immigration known or possible?
No
Would immigrants be adapted to survive in Canada?
n/a
Is there sufficient habitat for immigrants in Canada?
n/a
Is rescue from outside populations likely?
n/a
Current Status
- COSEWIC: Endangered (April 1978), Endangered (April 1997), Endangered (May 2000), Endangered (April 2008);
- Province of B.C.: Endangered;
- US Endangered Species Act: Endangered;
- IUCN: Endangered
Status and Reasons for Designation
Status: Endangered
Alpha-numeric code: A2a; C2a(i); D1
Reasons for Designation: Fewer than 30 mature wild-born individuals of this Canadian endemic remain in the wild. Despite the apparent initial success of reintroductions, the wild population of this species remains extremely small and could be subject to stochastic events. Ongoing predation remains high and there are potential threats from inbreeding and climate change
Applicability of Criteria
- Criterion A (Decline in Total Number of Mature Individuals): The total population has declined by 80% over the last 3 generations if released captive-bred marmots are excluded. Currently, the total population would likely continue to decline without reintroduction of captive-bred marmots.
- Criterion B (Small Distribution Range and Decline or Fluctuation): Although the range is very small, the decline may not be continuing (if reintroductions are included – otherwise a life-table analysis suggests a lambda of 0.89) and there are no extreme fluctuations. The population cannot be considered severely fragmented because dispersal is known among the Nanaimo Lakes colonies – the marmots on Mount Washington, however, are completely isolated.
- Criterion C (Small and Declining Number of Mature Individuals): There are only about 20-30 mature individuals, they would be declining in the absence of reintroductions and all populations are extremely small.
- Criterion D (Very Small Population or Restricted Distribution): There are less than 30 adults.
- Criterion E (Quantitative Analysis): n/a
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