Monitoring and Comparing Fine-Scale Movements and Habitat Preferences of Southeastern Appalachian Brook Trout and Rainbow Trout

 

Joseph Shaw
Presented: Spring 2015
Committee: JJ Apodaca, Mark Brenner, Robert Hastings

The range of native Southern Appalachian Brook Trout, Salvelinus fontinalis, has been greatly reduced from a history of logging, land clearing and other environmental degradations. They are also forced to compete with a variety of supplemented exotic trout species. The Brook Trout is the only salmonid species native to the southern Appalachian region of and is of great value ecologically, culturally, recreationally and economically. While many conservation strategies are in place to protect this fish, crucial information about how exotic species outcompete native Brook Trout is unknown. Furthermore, fisheries biologists are in need of effective methods to monitor Trout populations on a fine-scale and individual basis, in order to quantify physical barriers to movement and migration abilities. The primary objective of this study is to explore passive integrated transponder (PIT) identification of trout using a portable, in-stream antenna. In using this technology, we compare microhabitat preferences of native Brook Trout and exotic Rainbow Trout. Fish were collected from a stream considered to be typical of common native Southern Appalachian Brook Trout habitat, by electroshocking, implanting individuals with PIT tags and monitoring fish through the months of February and March, 2015. Fish as small as 80 mm in length had 100% survival and 93% tag retention and were successfully detected. In general, Rainbow Trout were observed to actively position themselves in locations that seemed to increase their access to food and potential for growth, while Brook Trout seemed less inclined to do so. This monitoring method proved to be effective, and insights into how exotic Rainbow Trout may outcompete native Brook Trout for habitat were attained.
“Key Words”: Brook Trout; Fine-scale movements; Microhabitat preferences; Passive Integrated Transponders (PIT tags); Rainbow Trout