Sea turtle bycatch in tuna fisheries occurs in several ways, through hooking on longlines, entanglement in longlines, gillnets and purse seine FAD netting (both above and below the waterline), and they are sometimes encircled in purse seine nets. Successful bycatch mitigation techniques for longlines include replacing squid with fish bait, using circle hooks with a moderate (<100) offset, deep setting, reducing daylight soak duration, limiting retrieval during daylight hours, and dynamic spatial and temporal measures (e.g. TurtleWatch). For gillnets, net illumination is effective. Improved purse seine FAD designs, i.e., biodegradable and non-entangling, are being tested for their potential to reduce bycatch. Utilisation of safe handling and release techniques successfully improves post-release survival, for all gear types.
SeaLlifeBase is a source of biological and distribution data for sea turtle species. Well illustrated species profiles can be found in the 'Marine Turtles of the Maldives' (green, hawksbill, olive ridley, loggerhead and leatherback turtles). NOAA's 'Find a Species - Sea Turtles' has information on protection status, biology and population status, distribution, threats, conservation measures and research. Locate handy Species ID guides here.
|Dermochelys coriacea (new FAO)
|EASTERN PACIFIC GREEN TURTLE
|OLIVE RIDLEY TURTLE
|MARINE TURTLES NEI