Analyses of six years of spotted seatrout (Cynoscion nebulosus) pond culture trials

Spotted seatrout (Cynoscion nebulosus) pond culture trials (52) were conducted on the central Texas coast from 1983 through 1988. All ponds were stocked with 2-day-old larvae at 45 000 to 2 075 000/ha, 9 to 28 days after initial filling and fertilization. Zooplankton, dissolved oxygen concentration, salinity, and temperature were routinely sampled throughout the culture period. Ponds were harvested 20 to 30 days after stocking. Stepwise multiple regression analyses were used to examine the effect of 38 independent variables associated with stocking density, the length of the culture period, fertilization, water quality, and zooplankton densities on percent harvest, number of fish harvested/ha, and kg of fish harvested/ha day^-1 of culture. Mean temperature, mean polychaete larvae densities for the culture period, and minimum dissolved oxygen concentration observed explained 69% of the variance in percent harvest. Mean temperature, stocking density, and mean polychaete larvae densities in the second, third, and fourth week after stocking explained 79% of the variance associated with number of fish harvested/ha. Variation observed in kg of fish harvested/ha day^-1 of culture was best explained (R² = 0.76) by mean temperature, stocking density, and mean polychaete larvae densities in the first and fourth week after stocking. Polychaete larvae density, especially during the latter stages of culture, was statistically the most important factor associated with production of spotted seatrout from larvae to ≈ 30 mm TL fingerlings.