Developing Strategies to Reduce Incidental Capture of Sea Turtles


Meeting Abstract

P1.35  Jan. 4  Developing Strategies to Reduce Incidental Capture of Sea Turtles BARRAZA, U.*; CUEVA, L.; FIGUEROA, A.; FISLER, S.; HALL , L.; RANGEL, N.; SILLAS, S.; SWIMMER, Y., WANG, J.; Aquatic Adventures Science Education Foundation, Hoover High School; Aquatic Adventures Science Education Foundation, Hoover High School; Aquatic Adventures Science Education Foundation, Hoover High School ; Aquatic Adventures Science Education Foundation; Aquatic Adventures Science Education Foundation, Moss Landing Marine Laboratories ; Aquatic Adventures Science Education Foundation, Hoover High School; Aquatic Adventures Science Education Foundation, Hoover High School; NOAA, Pacific Islands Fisheries Science Center; University of Hawaii at Manoa sharafisler@aquaticadventures.org

All species of sea turtles are listed as endangered or threatened. Over the past two decades, many sea turtle populations have declined. Turtle bycatch associated with various fisheries is thought to be one factor. One such fishery, pelagic longlining, is estimated to interact with thousands of sea turtles. Our preliminary experiments tested strategies aimed at reducing sea turtle interactions with fishing gear. Using tangle nets set in the Estero Coyote, Baja California, we examined the catch rates of green turtles (Chelonia mydas). During the day, we tested the effects of shark shaped silhouettes on turtle catch rates. At night, we examined the effects of light sticks on turtle catch rates. Previous experiments suggest that turtles avoid shark shapes. Our results in Baja California indicate a decrease in turtle capture rates when shark shapes were present. This preliminary result suggests that shark silhouettes may work as a deterrent to sea turtles in certain fisheries. Lightsticks used in the longline fisheries are thought to be one cue that attracts turtles to the longlines. Our initial field experiments, however, suggest that turtles are caught less when lightsticks were present. In this situation, lightsticks illuminate the net and may allow turtles to avoid becoming entangled.

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