GASTRIC EVACUATION IN THE YOUNG LEMON SHARK, NEGAPRION-BREVIROSTRIS, UNDER FIELD CONDITIONS

Gastric evacuation in young lemon sharks, Negaprion brevirostris, was studied in a field enclosure. Regression analysis was used to evaluate the adequacy of linear, exponential, and square root models in describing the decrease in stomach contents with time after feeding. The linear model produced the best fit and was thus used to compare gastric evacuation at the three temperatures. Gastric evacuation in young lemon sharks is considerably longer than for carnivorous teleosts but shorter than for other elasmobranchs. These differences are the result of differing energy requirements determined by the physiology and behavior of the species.