Movement and Diel Habitat Use of Juvenile Neosho Smallmouth Bass in an Ozark Stream

Documenting fish movement patterns and examining relationships with both fish and habitat characteristics are essential aspects of sound conservation and management. Stream fish movement and habitat use have been associated with a myriad of factors, and variability among individuals is common. Movement and habitat use patterns of juvenile Smallmouth Bass Micropterus dolomieu in streams are poorly understood, particularly for the Neosho subspecies M. dolomieu velox. Our study objective was to determine diel movement patterns and microhabitat use by juvenile Neosho Smallmouth Bass during late autumn. In 2016, we surgically implanted radio transmitters into 13 juvenile Smallmouth Bass in Honey Creek, Oklahoma. We tracked the fish by using radiotelemetry on 41 occasions over the 26-d tag life and located fish throughout the diel cycle to characterize movement and habitat use. Movement patterns varied among individual fish, with cumulative movements ranging from 33 to 1,302 m. Incremental displacement (the distance moved between two consecutive relocations) increased slightly with warmer water temperatures and increasing fish size. Although there was also considerable individual variation in habitat use patterns, deeper habitats were associated with larger juvenile Smallmouth Bass and daytime. Fish also tended to use higher-velocity habitats during the day, and this trend increased over the duration of the study. Our results suggest high individual variation in both movement and habitat use by juvenile Neosho Smallmouth Bass across the diel cycle. We show that juvenile Smallmouth Bass move among microhabitats and would benefit from management actions that maintain and promote instream habitat complexity. Future efforts focused on juvenile Smallmouth Bass movement over longer time periods would be beneficial for understanding movement and habitat use dynamics across a greater range of seasonal and environmental variability.