Document Type


Date of Degree Completion

Spring 2015

Degree Name

Master of Science (MS)



Committee Chair

R. Steven Wagner

Second Committee Member

Joseph G. Lorenz

Third Committee Member

Kristina A. Ernest


Understanding the impact of different landscape features on the movement of genes among populations can be helpful in managing wildlife populations. Our study used GIS tools to compare genetic connectivity among 13 American pika (Ochotona princeps) habitat patches across an approximately 77 square km area adjacent to Interstate 90 near Snoqualmie Pass, WA. Tissue samples were collected from 85 individuals and genotyped at six microsatellite loci to determine genetic differentiation among each pair of patches. A variety of models estimating the influence of landscape factors on gene flow were then used to find “resistance scores” between each pair of patches using the Circuitscape program. Partial Mantel tests, which removed the effect of isolation by distance (IBD), compared the corresponding genetic and geographic matrices to assess which geographic model resulted in the best fit. A number of models showed significant correlations when compared to IBD but none of the top models was significantly stronger than the remaining top models. Successful models included specific elevation and highway models as significant components. Results from this study suggest that increasing connectivity at specific areas, such as Gold Creek Bridge and Price/Noble Creeks will increase genetic connectivity.