JOHN BARRY TAYLOR, JOHN A. HARGREAVES, AND DAVID J. WISE, Department of Wildlife and Fisheries, Mississippi State University, Box 9690, Mississippi State, Mississippi 39762, USA

Although feeding activity of catfish has been shown to be related to water temperature, fish size and health, and density and biomass, large daily variation in feeding activity has been observed in commercial ponds despite maintenance of these conditions at a constant level. Anecdotal evidence suggests that fluctuation of dissolved oxygen, as well as other water quality and meteorological parameters, also influence feeding activity. We used state-space time series modeling to relate daily fluctuations in feeding activity (as measured by amount of feed applied to each pond) to fluctuations in amount fed, early morning dissolved oxygen, mean water temperature, and total cumulative solar radiation from preceding days for 25 commercial channel catfish ponds in Mississippi. The model indicated a significant inverse relationship between amount fed and the amount fed the previous day in 24 of 25 ponds. Additionally, amount fed was significantly and directly related to total cumulative solar radiation the previous day in 22 of 25 ponds. No consistent relationships were found between amount fed and early morning dissolved oxygen or mean water temperature on previous days. Knowledge of feeding activity and meteorological conditions from previous days can assist commercial producers in prediction of daily variation in feeding activity.