Movement of Native and Hatchery-Reared Game Fish in a Warm-Water Stream

Abstract

Movement of 248 marked and recaptured native smallmouth bass (Micropterus dolomieui), native rock bass (Ambloplites rupestris), and hatchery smallmouth bass released in a headwater tributary of the Little Miami River of Ohio during 1953 through 1957 is described. More than 91 percent of the native fishes of both species reported by anglers were taken within 1/2 mile of release points. Recaptures made with electric shocker and hoop nets indicated that appreciable numbers of native fish remained within limited areas of one to several pools between successive years. Considerable numbers of stocked smallmouth bass moved away from release points. A total of 35.7 percent of fish stocked in optimum habitat in 1953 and later recovered by anglers had moved distances greater than 1/2 mile. All fish stocked in submarginal habitat upstream in 1955 and later recovered by anglers moved more than 1/2 mile. Except for one recapture 6 miles upstream from the release point, all returns of stocked fish were from downstream at distances ranging up to 70 miles. The proportion of fish stocked in optimum habitat in 1953 and recaptured 11 to 50 miles downstream increased significantly from 1953 to 1954, suggesting a progressive downstream dispersal. Movement of hatchery smallmouth bass was independent of size at stocking in 1953. Rapid disappearance of the 1953-stocked fish may have resulted from higher mortality, as well as from movement.