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Published on: December 5, 2016
Small effective population size in the long-toed salamander
W C Funk1, D A Tallmon, F W Allendorf
1Division of Biological Sciences, University of Montana,, Missoula 59812, USA. wcfunk@selway.umt.edu
Molecular Ecology
|December 3, 1999
Summary
Effective population sizes for long-toed salamanders were estimated using genetic data. Results suggest small population sizes, highlighting conservation needs for amphibians facing habitat fragmentation.
Area of Science:
- Ecology
- Population Genetics
- Conservation Biology
Background:
- The long-toed salamander (Ambystoma macrodactylum) is a species of conservation concern.
- Estimating effective population size (Ne) is crucial for understanding population viability.
- Amphibian populations globally face threats from habitat fragmentation and isolation.
Purpose of the Study:
- To estimate the effective population sizes (Ne) of six long-toed salamander populations in Montana and Idaho.
- To compare empirical Ne estimates with simulated data to infer actual population sizes.
- To discuss conservation implications of low Ne in amphibians.
Main Methods:
- Allozyme data were collected from salamander populations in 1978, 1996, and 1997.
- The temporal allele frequency method was employed to estimate Ne.
- Observed Ne distributions were compared to simulated population data.
Main Results:
- Five of six Ne estimates ranged from 23 to 207, with a mean of 123.
- One population exhibited an Ne estimate indistinguishable from infinity.
- Comparison with simulations suggested actual Ne values for the six populations were likely under 100.
Conclusions:
- The estimated Ne values for long-toed salamanders are generally small, consistent with other amphibian studies.
- Small effective population sizes may increase vulnerability to genetic drift and inbreeding.
- Habitat fragmentation poses a significant threat to amphibian populations with small Ne, necessitating targeted conservation efforts.
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