Publication Date

Fall 2012

Degree Type

Thesis

Degree Name

Master of Science (MS)

Department

Biological Sciences

Advisor

Leslee Parr

Keywords

Dungeness crab, larval dispersal, microsatellites, mitochondrial DNA

Subject Areas

Biology

Abstract

Genetic variation was assessed using mitochondrial DNA and microsatellite markers from Dungeness crab between Iceberg Bay, British Columbia and San Luis Obispo, California. We found little pattern in overall genetic variation between sites in both marker types, and no significant Isolation by Distance model was fit. Site-specific variation in mitochondrial DNA haplotype frequencies suggested the existence of three subpopulations associated with the Alaska Current, the Puget Sound, and the California Current, but microsatellite DNA evidence did not support it. The ratio between sampling size for microsatellite markers and fragment size polymorphisms was low, limiting the resolving power of microsatellite DNA for neutral variation. Average pairwise Fst values for Iceberg Bay, British Columbia against all other populations was 0.156, as compared to the average pairwise Fst of 0.028 across all populations. In the southern region of the Puget Sound, Nisqually, Washington had a lower pairwise Fst of 0.044 but contained a large number of site-specific, unique mtDNA haplotypes. Additionally, we found 41 mtDNA haplotypes in 445 samples taken, with 23 of those haplotypes as "singletons," suggesting that Dungeness crab went through a recent, post-bottleneck population expansion, likely associated with the most recent glacial relaxation.

Download

Share

COinS