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Multiple introductions of the eastern fox squirrel (Sciurus niger) in California
Sieara C Claytor1, Alan E Muchlinski, Elizabeth Torres
1Department of Biological Sciences, California State University , Los Angeles, CA , USA.
Mitochondrial DNA
|January 21, 2014
Summary
Multiple introductions of eastern fox squirrels (Sciurus niger) into California are indicated by genetic diversity. Different native source populations likely explain the varied haplotypes found across the state.
Area of Science:
- Ecology
- Genetics
- Conservation Biology
Background:
- Eastern fox squirrels (Sciurus niger) were introduced to California over 130 years ago.
- Recent observations show an alarming expansion of their range within California.
Purpose of the Study:
- To determine if eastern fox squirrel introductions in California resulted from a single or multiple events.
- To analyze genetic diversity and haplotype distribution across different Californian regions.
Main Methods:
- Sequencing of 101 control region DNA samples from eastern fox squirrels.
- Analysis of genetic data from three distinct geographic regions in California: Los Angeles County, Alameda and Contra Costa counties, and Sacramento County.
- Construction of a haplotype network to visualize genetic relationships.
Main Results:
- Eleven distinct haplotypes were identified among the sampled squirrels.
- Haplotypes were infrequently shared between geographic regions, and no regional clustering was observed in the haplotype network.
- Los Angeles County exhibited the highest haplotype diversity.
Conclusions:
- The genetic data suggest multiple, independent introductions of eastern fox squirrels into California from different native source populations.
- The lack of clear phylogeographic structure in native fox squirrel populations complicates the precise identification of all introduction sources.
- Understanding introduction origins is crucial for managing the expanding range of this invasive species.
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