Cory T. Trego

Date of Graduation


Document Type


Degree Type



Davis College of Agriculture, Natural Resources and Design


Wildlife and Fisheries Resources

Committee Chair

J Todd Petty

Committee Co-Chair

Eric R Merriam

Committee Member

Stuart A Welsh


Brook trout Salvelinus fontinalis have experienced significant population declines throughout much of their native range, largely due to habitat loss. Increasing effort has been put toward restoring and preserving existing brook trout habitat in the face of continued loss under uncertain future conditions (e.g., climate change). We conducted a study designed to analyze both macroscale (i.e. at channel unit level) and microscale (i.e. within individual pools) habitat use in the context of stream restoration by brook trout and two competing nonnative salmonid species: brown trout Salmo trutta and rainbow trout Oncorhynchus mykiss. First we conducted a before-after-control-impact assessment of a multi-scale restoration project designed to improve brook trout habitat on the Shavers Fork, West Virginia by comparing trout use of habitat at the channel unit scale one year before and one and three years after restoration. We then used snorkeling surveys to assess and compare microhabitat preferences of brook, brown, and rainbow trout in constructed and natural pool habitats in Shavers Fork. Our over-riding objective of this project was to assess the response of brook trout and competing nonnative salmonids to habitat restoration in the Shavers Fork of the Cheat River, West Virginia at both the hydraulic channel unit scale and the microhabitat scale within individual pools. Channel unit shifts after habitat restoration suggests that restoration had significant impacts on macroscale habitat selection by these three trout species and that brown trout may be excluding brook trout from preferred reaches. Underwater observation of trout indicated that species occupied distinct microhabitats, but subsequent analysis revealed that much of the variation in habitat selection can be explained by estimated trout length. Brook trout occupying pools sympatrically with brown and rainbow trout occupied significantly different microhabitats than brook trout occupying pools allopatrically, suggesting competition between brook trout and nonnative salmonids is significantly influencing brook trout behavior and habitat selection. Future studies should consider removal of nonnative salmonids to determine habitat use and population trends in their absence from stream reaches.