A Plan to Reduce Sea Turtle Bycatch in Small-scale Gillnet Fisheries Using Illuminated Nets

Bycatch - the incidental capture of non-targeted species in fishing gear - threatens many different marine species. Fisheries bycatch threatens the continued survival of several sea turtle species, which have experienced population declines over the past several decades. New devices and gear modifications such as acoustic pingers, turtle excluder devices, and circle hooks have reduced the bycatch of marine mammals and sea turtles. Because sea turtles use visual cues to aid in foraging habits, methods that use visual deterrents to reduce incidental sea turtle capture in gillnets are an emerging research area. Past experiments have found that attaching light sources to gillnets reduces sea turtle bycatch without affecting target catch rates or catch market value; however, these methods were too costly and time-intensive to the fishers to be practical. This project will test the effectiveness of using illuminated nets to reduce sea turtle bycatch. Portions of the nets will be composed of a phosphorescent material that absorbs wavelengths of light and glows in the dark. The experiment will be carried out in summer 2010 in Punta Abreojos and Bahía de los Ángeles, Baja California, Mexico. Students from underserved communities in San Diego will assist in data collection and analysis as part of the Ocean Leaders Initiative with the non-profit Ocean Discovery Institute.