Effect of Stocking Density on Growth Performance of Nile Tilapia (Oreochromis niloticus) in Earthen Ponds, Benue State

This study evaluated the effect of varying stocking densities on the growth performance and survival rate of Nile tilapia (Oreochromis niloticus) cultured in earthen ponds in Benue State, North Central Nigeria. Tilapia farming is expanding rapidly in Benue State due to its adaptability to local climate and market demand. Fingerlings were stocked at three densities: 1 fish per square metre, 2 fish per square metre, and 3 fish per square metre, in nine earthen ponds in a completely randomised design replicated three times. Fish were fed a commercial diet at 3 percent body weight twice daily over a 12-week culture period. Growth parameters measured included final mean weight, specific growth rate, feed conversion ratio, and survival rate. Results revealed that fish stocked at the lowest density achieved the highest mean final weight of 245 grams and the best feed conversion ratio of 1.68. As stocking density increased, specific growth rate declined significantly, while mortality events became more frequent, particularly during the sixth week. Water quality deteriorated more rapidly in high-density ponds, with dissolved oxygen levels falling below optimal thresholds during peak feeding hours. The highest density treatment recorded the lowest survival rate at 71 percent. These findings confirm that overcrowding negatively impacts individual fish performance and recommend that smallholder farmers in Benue State maintain densities that balance yield per unit area with individual fish welfare. Keywords: stocking density, Oreochromis niloticus, growth performance, aquaculture, Benue State