Meeting Abstract

68.5  Thursday, Jan. 6  Examining Behavioral Responses For Stability of Batoids in Response to Waves HOFFMAN, J.L.*; FISH, F.E.; BART-SMITH, H.; West Chester Univ., Pennsylvania; West Chester Univ., Pennsylvania; Univ. of Virginia, Charlottesville Jh688236@wcupa.edu

The presence of external perturbations in the aquatic environment necessitate behavioral responses by fish to stabilize the body. The orbital flow in waves may present challenges to maintain stability in rays with a broad planform shape. Behavioral and kinematic responses of Potamotrygon motoro, Dasyatis sabina, and Rhinoptera bonasus in the order Myliobatiformes, were observed when subjected to unsteady forces associated with waves. Rays were recorded with high-speed video at 250 fps in a wave tank. The responses of individual rays were observed as a single wave impacted the animal either posteriorly or anteriorly. Video data was analyzed with a 2D motion analysis system. Rhinoptera was able to stabilize itself by decreasing its swimming speed and pectoral fin amplitude. The ray was able to brake as the wave approached and suspend itself within the wave before resuming swimming. Dasyatis and Potamotrygon swam along the bottom of the tank and used avoidance behaviors in response to the wave. These rays either increased their fin amplitude and swimming speed to accelerate and turn to rapidly retreat from the wave, or they maintained station on the bottom of the tank by reversing the direction of their pectoral fins to break. The behavioral and kinematic responses to waves by the pelagic Rhinoptera and the benthic Dasyatis and Potamotrygon were associated with differences in the ecology of these species.