Oversized fish has been a significant problem for the Alabama catfish industry in recent years. These leftover fish, described as “big fish” by the catfish industry, remain in ponds following harvest and often grow beyond premium market sizes (0.45 – 1.81 kg; 1.25 – 4 lbs.). Big fish in excess of 18 kg have been routinely reported by commercial farmers and catfish processing plants. This issue is especially exacerbated under production scenarios involving hybrid catfish, which can grow faster and to larger sizes than channel catfish. These leftover fish consume feed intended for the new stock, receive lower prices at harvest, and could potentially have a negative impact on the new stock through competition for feed, disease transmission, stress, or even cannibalism. Over the years there have been several anecdotal observations by farmers and researchers that would suggest these big fish engage in cannibalism, the question is to what extent, if any, these actions impact the overall survival of fingerling and stocker size fish. To investigate this production concern, we plan to conduct a series of electrofishing samplings following stocking of commercial ponds that are known to have issues with oversized fish. Shortly after new fingerlings are added to the pond (~1wk), oversize fish will be collected. The stomach contents of big fish will be analyzed to determine if they have been feeding on the newly stocked fish. The second portion of this investigation will consist of small-scale research pond-based experiments. Treatment A will represent the control group in which ponds will be stocked with fingerlings only and will be fed an appropriate feed ration to mimic normal production conditions. Treatment B will consist of ponds stocked with a small number of oversized fish (~ 3.6 – 18.1 kg; 8 - 40 lbs.) collected from west Alabama catfish farms. These fish will be allowed to acclimate to their new conditions for a minimum of 1 week prior to the stocking of fingerlings. Once the fingerlings are stocked, fish will be fed a ration that accounts for the presence of both the over-sized fish as well as the juveniles. Treatment C will be stocked in the same manner as treatment B, however, treatment C will receive a feed ration that only accounts for the fingerlings. After a pre-determined period, ponds will be harvested. During harvest all fish will be weighed and counted to determine the survival, and FCR. The large fish will be weighed, measured, and sampled to examine stomach contents. Fish otoliths will be collected to determine age. Data generated from this project should help gauge the impact oversized holdover fish have on performance and survival of newly stocked fingerlings. We plan to carry out controlled pond studies with both hybrid catfish and channel catfish. The findings of this study could further highlight the need for improvements in harvest and pond cleanout techniques not only to reduce losses due to missed market size fish and reduced prices, but to improve production performance and profitability of subsequent crops.