Effects of water exchange and abiotic factors on zooplankton and epibenthic fauna in shrimp ponds

摘要: Assemblages of zooplankton and epibenthic invertebrates were collected from a commercial Penaeus monodon (Fabricius) pond at fortnightly intervals over an entire grow-out season. The inlet outlet water also sampled intensively three 1-week periods throughout the Before stocking ponds with shrimp postlarvae, copepods dominated zooplankton. Immediately after stocked, there was rapid decline in numbers, particularly dominant larger copepods, suggesting heavy predation by postlarvae. For rest season, barnacle nauplii component pond. Pond exchanges had little detectable influence on composition or density assemblage. Instead, dominance appeared to have been maintained steady recruitment due reproduction While changes biomass not correlated physico-chemical characteristics, positively temperature, negatively pH, dissolved oxygen secchi disc readings. Epibenthic faunal peaked end while during middle part Sergestids (Acetes sibogae Hansen) most abundant taxa. No correlations found between parameters fauna density. Abundances related densities, that trophic interactions these assemblages is important. Acetes captured samples water, only single occasion large numbers water; this, notable increase number This evidence, together lack size suggests exchange important but unpredictable source into results emphasize benefits ensuring appropriate introduced ponds, when they are filled, support immediately stocking. will depend initial inoculum may be difficult manipulate once established. appear more likely change need monitored across if their presence reduces production through adverse impacts such as competition introduction disease deteriorated quality.