Food Habits of Blue Catfish (Ictalurus furcatus) Introduced into Lake Oconee, Georgia

Blue Catfish (Ictalurus furcatus) are native to the Coosa river drainage in northwest Georgia, but recently have been discovered outside of this range in Lake Oconee in 1997. In Lake Oconee, their abundance and growth rates have increased dramatically, but their food habits are unknown. Therefore, food habits of Blue Catfish were determined by examining the stomachs of 808 specimens from Lake Oconee’s upper and lower regions during four consecutive seasons beginning in summer 2012. Stomach contents were analyzed using the Index of Relative Importance. The dominant prey item during the summer was Asian Clams (Corbicula fluminea;98%). Dominant prey items for the fall season shifted to items including Asian Clams (46%), Mayflies (Ephemeroptera; 23%), Flies (Diptera;16%), and Threadfin Shad (Dorsoma petenense;15%). Winter dominant prey items shifted to Mayflies (45%), Threadfin Shad (35%), and Asian Clams (16%). Mayflies (84%) dominated the spring prey diet. The upper region fish relied heavily on Asian Clams (48%) and lower region fish relied on Mayflies (36%). These results demonstrate that Blue Catfish in Lake Oconee are opportunistic predators preying on whatever is seasonally abundant; the results also show that native bi-valves and native fishes are not a major part of the diet.