New Nitrogen Fertilization Recommendations for Bluegill Ponds in the Southeastern United States

Abstract

A nitrogen fertilization experiment was conducted in 33-year-old ponds at the Auburn University Fisheries Research Unit, Auburn, Alabama, after sediment removal and renovation. Twelve ponds were treated with 3 kg P₂O₅ (1.3 kg P)/ha, and ammonium nitrate was applied to give a range of nitrogen application rates (0–14 kg/ha). The maximum production of bluegills Lepomis macrochirus was achieved at 6 kg N/ha. The optimum fertilizer application rate for ponds from which sediment had been removed was 6 kg N with 3 kg P₂O₅ (1.3 kg P)/ha, which implies the following ratios: N:P₂O₅ = 2:1 and N:P = 4.6:1. This fertilization rate should be more appropriate than the commonly used rate of 9 kg N with 9 kg P₂O₅ (3.9 kg P)/ha for new ponds in the southeastern United States.