Diel movement of brown trout in a southern Appalachian River

Radio telemetry was used to monitor the diel movement of 22 brown trout Salmo trutta (268-446 mm in total length, TL) in the Chattooga River watershed. Forty-seven diel tracks, locating individuals once per hour for 24 consecutive hours, were collected for four consecutive seasons. High variability in movement both within and among individual brown trout resulted in similar seasonal means in total distance moved, diel range, and displacement. The majority of fish moved a total distance of less than 80 m within a diel range of less than 80 m and had a displacement of less than 10 m. Brown trout were more likely to occur in pool habitat independent of season or period of the day. Hourly movement patterns differed among seasons. During the winter and fall, trout moved only around sunrise; during the spring, they moved around sunrise, sunset, and intermittently throughout the night. Large brown trout (>375 mm, TL) were found to move greater total distances and establish wider diel ranges than small brown trout. Overall, most brown trout exhibited restricted diel movement within a single riffle-pool or run-pool sequence.