Meeting Abstract

P3.114  Monday, Jan. 6 15:30  Getting Hooked: A study to understand sea turtle longline bycatch WARRAICH, TN*; WYNEKEN, J; Florida Atlantic University; Florida Atlantic University twarraic@fau.edu

Loggerhead and leatherback sea turtles are often caught as longline bycatch in fishing industries worldwide. These two species of sea turtle differ greatly in their life histories and morphologies. Leatherbacks tend to be foul hooked, hooked externally in the shoulder or flippers, while loggerheads tend to be hooked in the mouth or they swallow the bait and get hooked in the esophagus or stomach. Although the number of loggerheads and leatherbacks caught decreased after the switch in gear type, leatherbacks mouth hooking increased while foul hooking decreased. We studied the prey approach and attack behavior of both species. The increase in leatherback mouth hooking may be explained by the reduced availability of hooks that snag the turtles’ flippers and shell (circle hooks) and the tendency to re-approach and ingest the baits if they missed their target on the first attempt. We compared prey attack and behavior and accuracy in the presence of visual targets. Waterborne squid and jellyfish odors were used to elicit feeding behavior in the two species. We found that loggerheads have exceptionally good aim and almost always make contact with their intended target while feeding. Leatherbacks frequently overshoot and miss their intended target then have to re-approach the target multiple times before making contact.