Age Determination of Hybrid Catfish and Channel Catfish from Commercial Catfish Farms

Abstract Processing plants prefer live catfish ranging from 0.45 to 1.81 kg as they are readily processed and sold to established markets. Catfish routinely escape harvest, become “big fish” (>1.81 kg) in one to two production cycles, receive a reduced price, and can reduce farm profitability. This study determined age structure of Channel Catfish Ictalurus punctatus and hybrid catfish (male Blue Catfish Ictalurus furcatus × female Channel Catfish) that were “big fish” from commercial catfish ponds and estimated growth rates to determine when fish reach these sizes. In summer 2018, 153 Channel Catfish and 134 hybrid catfish were collected from commercial catfish farms in western Alabama and aged using lapilli otoliths. Hybrid catfish had faster growth than Channel Catfish and were larger at every age-class sampled during the study. Premium-sized fish were comprised solely of age-2 and age-3 fish for both species, but 72% of age-2 Channel Catfish were premium size, compared to only 40% of age-2 hybrid catfish. On average, Channel Catfish and hybrid catfish reached “big fish” size in 2.5 and 1.5 years, respectively. Thus, farmers should try to harvest most fish within these time frames or renovate ponds to mitigate these issues.