Restoring Brook Trout to North Carolina's National Forests

by DiBacco, Sara

Stream systems in the Southern Appalachian Mountains represent the southern limit of brook trout (Salvelinus fontinalis) distribution in the eastern United States and are home to the region’s only native salmonid, the Southern Appalachian Brook Trout. Currently, the species occupies only 25% of its former range in the region, but in North Carolina, opportunities exist to restore brook trout to high quality National Forest watersheds. The purpose of this project is to provide the information necessary to design a watershed-specific restoration strategy for the Fires Creek Watershed, Nantahala National Forest and to develop a model that predicts natural migration barriers within a stream network.

A geographic information system (GIS) is the primary analysis tool used to derive, interpret, and display relevant data. In the Fires Creek Watershed, migration barriers are identified and characterized to delineate potential brook trout reintroduction sites. The watershed is also assessed as a target for brook trout restoration according to five criteria. These are the historical presence of brook trout, the current distribution of trout in the basin, the genetic identity of potential donor populations, site accessibility, and current and future habitat suitability. Barrier data are also used to develop a classification and regression tree (CART) model to predict barrier locations.

Results show that numerous opportunities exist to restore brook trout to the Fires Creek Watershed. The most effective restoration strategy combines the availability of protected habitat, as delineated by migration barriers, with information extracted from the comprehensive assessment. The model provides the framework for a tool that improves the efficiency of completing restoration projects, but results suggest that higher resolution data is necessary to increase prediction success. Overall, this work contributes to the development and implementation of brook trout restoration projects in North Carolina’s National Forests.