Movement and Emigration of Yearling Blue Catfish Stocked in Two Ohio Reservoirs

In an effort to diversify reservoir catfish angling opportunities, approximately 13,000 yearling blue catfish were stocked into Dillon and Hoover reservoirs in October of 2010 and 2011, respectively.  The hydrodynamics and water management of these reservoirs differs markedly; Dillon Reservoir is a flood control reservoir with short water retention (10d) and Hoover is managed primarily for drinking water and has longer retention (190d).  In each year, three thousand of the stocked fish were marked with Carlin tags and fifty were surgically implanted with coded acoustic pingers.  In both systems, receivers (VR2W) were positioned at various locations throughout the reservoir and in the dam tailwaters.  Fish detections on the Dillon tailwater receiver indicated that most fish exited the system during the 14d winter drawdown period in late November 2010.  More than 95% of the angler reports from the Dillon stocking came from the rivers downstream.  We documented no emigration from the fish stocked into Hoover Reservoir.  All angler reports from Hoover were fish caught in the reservoir and no fish were detected on the receivers downstream of the reservoir.  Upstream movements were associated with periods of reservoir filling and downstream movement (including emigration) was associated with declining water levels.