THE INFLUENCE OF FEEDING ON PREDATORY TACTICS IN A WATER BUG

The tropical belostomatid Diplonychus indicus Venk. & Rao (Heteroptera : Belostomatidae) forages both actively and from ambush, changing freq uently from one predatory mode to the other. Analyses presented here o f the influence of feeding and of developmental stage on several locom otory and predatory parameters show that the fact that a bug was eatin g did not prevent it from reacting to and from seizing prey items, but it did influence the mode of predatory attempts. Feeding bugs were le ss active and they foraged actively less frequently, but feeding did n ot affect the frequency of predatory attempts from ambush. No importan t variations during development were found and first stadium larvae be haved similarly to adults. Capture success rates were higher at all de velopmental stages during a meal than when a bug was not eating and re jection rates were lower during a meal. These results suggest that, wh en eating, Diplonychus indicus bugs aim more successfully at prey item s they are more likely to capture and to eat.