With increasing experience with the novel prey, Daphnia, the fish became less hesitant to attack Daphnia. The fish took fewer nonprey items per prey item with increased experience. They also became more efficient in handling the novel prey. There was no indication of the formation of a search image. The multiple regression model revealed that, although the fish grew during the experimental period, their increased size did not contribute significantly to the increase in capture success. Contrary to previous studies size did not influence capture success within the size range used in these experiments. The individual variation in capture success was large in all groups of Cichlasoma managuense. The most successful predators were the fish who persistantly attempted to catch prey and had the highest number of previous experiences with the novel prey. The morphological variable weight was negatively correlated with capture success, which may suggest that a hungrier fish is more motivated to prey and a more successful predator. An increase in eye diameter brought about an increase in capture success, due probably to an increased visual acuity, hence it may suggest a possible ecological effect of this morphological variable.