From the 1999 Southern Division of the American Fisheries Society Midyear Meeting held in Chattanooga, Tennessee.

Multiple Electrofishing Removals as a Management Tool For Restoration of Southern Appalachian Brook Trout

Matt A. Kulp and Stephen E. Moore, Great Smoky Mountains National Park, 107 Park Headquarters Road, Gatlinburg, Tennessee 37738

Keywords: trout removal


We evaluated multiple electrofishing removals of rainbow trout Oncorhynchus mykiss in one year as a management tool for the restoration of native brook trout Salvelinus fontinalis in a small southern Appalachian stream. Six, three-pass depletion removal efforts were conducted between June 1996 and October 1997 using backpack electrofishing gear. After removal 4 (October 1996), 105 native southern Appalachian brook trout of various age-classes were reintroduced into Mannis Branch. No rainbow trout were collected during removal 6, indicating five removals were required to successfully eliminate rainbow trout from Mannis Branch. During the study, 428 rainbow trout were removed from the treatment area. The initial removal collected 296 rainbow trout (70% of total), of which 62 were YOY (21%) and 234 were age-1 (79%) or older. Removals two through five were dominated by YOY rainbow trout (57-83%). The initial two removals successfully eliminated 96% of the reproductively mature adults as well as 86% of the YOY. Surveys conducted in May 1997 indicated adult brook trout successfully spawned initiating re-population of the treatment area. Initial population estimates were compared to the actual catch to assess the accuracy of population estimators. Population estimates from removal one underestimated the actual population size by 30%. It was not until after removal three that the actual number of rainbow trout fell within the population estimate 95% confidence interval for the treatment area. Multiple removals exhibited no negative population level effects on rainbow trout or blacknose dace Rhynichthys atratulus in Mannis Branch or a control stream, despite being exposed to six, three-pass depletion electrofishing efforts. Based upon these results, a minimum of two removals conducted per summer should eliminate rainbow trout reproduction and significantly reduce the number of years required to successfully restore a small southern Appalachian stream.


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