Growth and Swimming Endurance of Juvenile Channel Catfish in High Temperature Environments

Channel catfish (Ictalurus punctatus) are important to aquaculture and natural ecosystems, however little is known regarding effects of high summer temperatures, which are predicted to increase with climate change. Therefore, two studies were conducted to examine physiological effects of high temperatures on juvenile channel catfish. The first examined effects of three cycling thermal regimes (23-27°C, 27-31°C, and 31-35°C) characteristic of culture environments in Mississippi on growth, food consumption, feed conversion ratio, specific growth rate, and activity. The second study measured active and resting metabolic rates and swimming endurance at constant temperatures (27, 31, and 35°C). The best growth and feed conversion occurred at 27-31°C and activity was greatest at 31-35°C. Active metabolism and swimming endurance decreased at 35°C. These results indicate high summer temperatures reduce food consumption, increase activity, impair metabolism and endurance, and therefore present challenges to the culture and management of channel catfish