FEEDING HABITS OF PELTEOBAGRUS NITIDUS IN LAKE DONGTING

The present study dealt with the feeding habits of Pelteobagrus nitidus by stomach contents analyses of samplescollected monthly from April 2004 to February 2005 in Lake Dongting. Results showed that P. nitidus preyed allthe year with its feeding activity being higher in spring and winter than in summer and autumn. Also, the feeding intensitydeclined in the breeding period. There were 17 prey items being identified. Food diversity was the highest in springand the lowest in winter. Aquatic insects larvae and malacostraeans dominated the stomach contents, accounting for90.6% in weight percentage. Aquatic insects consumed by the fish mainly included Ephemeropterans (numericalpercentage: 24.2%; weght percentage: 41.1%), Dipterans (numerical percentage: 58.4%; weght percentage: 7.5%) andOdonatans (numerical percentage: 3.2%; weght percentage: 22.8%). Food composition of the fish varied significantlywith the season. In terms of numerical percentage, Dipterans (64.6% and 85.0%, respectively) dominated the diets inspring and winter, while Dipterans (28.2%) and Odonatans (22.3%) dominated in summer, and Ephemeropterans (45.7%)did in autumn. In terms of weight percentage, Dipterans (53.0%) dominated in spring, while Odonatans (55.7%) dominatedin summer, and Ephemeropterans (53.7% and 76.6%) did in autumn and winter. Analyses showed that the seasonalvariations of food composition of P. nitidus were correlated with variations of food resources in the water.