Effect of stocking density on growth and water quality for largemouth bass Micropterus salmoides growout in ponds.

摘要

Juvenile largemouth bass (initial weight 122.1 g) trained to accept artificial diets, were stocked into six 0.04-ha ponds at stocking densities of 6175 or 12 350 fish/ha. Fish were fed on a floating custom-formulated diet, containing 44% protein, once daily to satiation for 12 months (May 1994-May 1995). At final harvest, total yield of fish was greater (P<0.05) and feed conversion ratio significantly lower, for bass stocked at the higher density (4598 kg/ha and 2.3, respectively) than when stockedat the lower density (2354 kg/ha and 3.3, respectively). There was no significant difference in average weight, length or survival of bass stocked at both densities. Averaged over the study period, there were no significant differences in total ammonia-N, nitrite-N, or un-ionized ammonia concentrations in ponds in which bass were stocked at the 2 densities. The data indicate that largemouth bass of the size used in the study are amenable to pond culture at densities of at least 12 350 fish/ha and thathigher stocking densities may be possible.