
Meeting Abstract
P1.61 Sunday, Jan. 4 Prey Processing in Elasmobranchs STOEHR, A.S.**; WILGA, C.D.*; University of Rhode Island; University of Rhode Island ashley_stoehr@mail.uri.edu
Prey processing is an integral part of the feeding process, however, there are relatively few studies that focus on post-capture behavior in fishes. The hyoid arch has been shown to play a key role in the feeding mechanism of fishes. The position of the hyomandibulae is related to prey capture mode in elasmobranchs. How the position of the hyomandibula relates to jaw mechanics and the generation of pressure in the buccal, hyoid, and pharyngeal cavities is little understood for prey processing. This study compared the effects of jaw, hyoid and branchial arch morphology on prey processing in white-spotted bamboo sharks (Chiloscyllium plagiosum), spiny dogfish (Squalus acanthias), and little skates (Leucoraja erinacea), which possess lateral, slightly posterior, and anterior hyomandibular orientations respectably. The kinematics of the jaws, hyoid, and 3rd branchial arches and associated pressures were quantified during suction and bite processing. As expected, mouth opening and arch expansion primarily creates subambient pressures, while mouth closing and arch compression generates superambient pressures to move the prey within the oropharyngeal cavity. Bite events are longer in duration than suction events. Skates had the longest durations and bamboo sharks generated greater peak pressures for all events. The hyoid and pharyngeal arches move in synchrony during suction and bite processing in skates and dogfish, but not in bamboo sharks. The disparate cavity motions during prey processing reflects different degrees of cranial kinesis and morphological constraint among the elasmobranchs.