Comparative Swimming Performance of Juvenile Blue Catfish and Hybrid Catfish

Abstract

AbstractWe compared the swimming performance of juvenile blue catfish Ictalurus furcatus and hybrid catfish (female channel catfish I. punctatus × male blue catfish) using a protocol in which fish were forced to swim at a fixed velocity and their time to fatigue recorded at speeds of 30–120 cm/s. Hybrid catfish swam significantly longer than blue catfish at all of the speeds tested except 30 and 40 cm/s. The maximum sustained swimming speed (no fatigue in times ≥200 min) was 30 and 40 cm/s for blue catfish and hybrid catfish, respectively. The maximum prolonged swimming speed (fatigue in times >20 s but <200 min) was 100 cm/s for blue catfish and 120 cm/s for hybrid catfish. The burst swimming speed (fatigue in times <20 s) for blue catfish was 110 cm/s. The burst swimming speed for hybrid catfish was not determined; however, it is higher than its maximum prolonged swimming speed of 120 cm/s (highest speed tested). Hybrid catfish were able to swim longer before fatiguing than were blue catfish at 50 cm/s (156 versus 97 min) and at 60 cm/s (33 versus 6 min). Both blue catfish and hybrid catfish fatigued in less than 5 min at 70 cm/s, less than 3 min at 80 cm/s, and less than 60 s at 110 cm/s. No blue catfish swam at 120 cm/s while hybrids swam for 26 s at that speed. The results of this study will help fish producers understand the relationship between the speed of water currents produced by various aeration equipment and fatigue in pond‐raised blue and hybrid catfish fingerlings.