Spatial Distribution and Temperature Selection of Fish Near the Thermal Outfall of a Power Plant During Fall, Winter, and Spring

摘要

The movement patterns of 4 fish species: yellow perch (Perca flavescens), northern pike (Esox lucius), largemouth bass (Micropterus salmoides) and walleye (Stizostedion vitreum) were monitored by radio telemetry near the thermal discharge of a power plant (delta T 15C nominal). Fish movements relative to depth, temperature, center of the home range, discharge point, and release location are examined. Near thermally altered areas northern pike exhibited the greatest amount of movement followed by yellow perch, walleye and largemouth bass. Except for largemouth bass, thermal experience was found to be transitory. An overall mean winter temperature selection of 5.4C was determined for yellow perch. While only in the thermally altered area yellow perch had a slightly higher mean thermal experience, 6.3C. Yellow perch were not found to be attracted from the surrounding areas into the heated waters of the discharge bay during the cooler months.