Sea turtles can be found entangled in the nets of FADs or associated with the tuna school in the bunt. Regarding sea turtles and FAD fishing, the most effective bycatch mitigation focuses on the structure and/or configuration of the FAD itself, which was reviewed in the previous chapter.
All sea turtles are protected internationally, as these long-lived animals face a number of environmental challenges (breeding ground destruction, boat collisions, ingestion of marine debris, disease linked to ocean pollution), including interactions with fishers. There are seven species of sea turtle, with five commonly encountered during tuna fishing.
The current, and best, practice to avoid turtle mortality once the animal is entangled is the use of speedboats to release the turtles unharmed from the net before passing through the power block. The best time for this action is when the entangled turtle and net leaves the water on the way to the power block (at this point the hauling should be paused). If necessary, use clippers to cut the net. Disentanglement at the earliest possible stage maximizes survival. Speedboats can also be used to remove any free-swimming encircled turtles. When handling, do not lift the turtle by its flippers or use sharp objects (e.g., gaffs) to retrieve them. Hold the turtle by the sides of its shell and ease it into the water head-first as soon as possible. If the turtle appears unconscious (possibly due to entanglement underwater), place the turtle on a tilted surface so that its hindquarters are approximately 15 cm (6 in) higher than its head. This allows water to drain out of its lungs. Keep the animal moist (cover the body—but not the nose and mouth—with a wet towel or spray it periodically with water) and at a temperature above 15° C (60° F). Check the turtle’s reflexes by touching its tail or eyelid every three hours. An unconscious, but live, turtle may not react. If, after 24 hours, the turtle shows no recovery, it is likely dead. However if it does recover, release it gently into the water.