Functional design and swimming energetics of the freshwater pufferfish, Tetraodon fluviatilis

Measurements of morphometric characteristics pertinent to hydromechanical analysis were recorded, transformed where necessary and regression analysis was performed to relate the morphometric characteristics to standard body length. Terminal velocity measurements were recorded for a series of drop tank experiments. The data was converted into drag coefficients and Reynolds numbers and regression analysis was performed- to establish the specific relationships between those two hydromechanical parameters which were compared to theoretical estimates calculated from hydromechanical theory. High speed cinefilms of pufferfish fin and body motions made during forward swirriming were recorded and subsequently digitized onto a computer with a frame analyzer. The data was converted to distance and time from which the kinematic parameters of fins and body motions were calculated and compared to values found for other aquatic propulsive systems. A modified Actuator-Disc model was employed to estimate propulsive power and efficiency during steady forward swimming based on the morphometric, kinematic and hydromechanical parameters calculated for the pufferfish. Comparisons of the experimental estimates for drag and power were made with theoretical estimates and with estimates found for other aquatic propulsive systems. The efficacy of the modified Actuator-Disc model was discussed with respect to negating factors found during this study for the application of the model to multiple fin aquatic propulsive systems.Science, Faculty ofZoology, Department ofGraduat