This program is part of the Program PESQAR and contributes to the overall goal of implementing a responsible small-scale artisanal fishery within the Marine Reserve “Galera-San Francisco”.
One of the major bycatch problems exists in fisheries targeting Billfish (families Istiophoridae and Xiphiidae) and Common Dolphin-fish (Coryphaena hippurus), where surface long-lines with living or dead baits are typical gears. Unfortunately, marine turtles live in the same habitat and eat the same food as the targeted fishes, so that fishermen find turtles, e.g. Hawksbill (Eretmochelys imbricata) and Black Turtle (Chelonia mydas agassizii), entangled in the mother- or branch-lines with swallowed hooks. Scientific studies about the amount of unwanted turtles caught in these fisheries rarely exist, although fishermen report high bycatch numbers: one boat targeting Common Dolphin-fish catches up to 5-8 turtles with swallowed hooks in a 2-days fishing trip. The fleet capacity for this fishery in the village Galera alone amounts to 30 boats approximately. Fishing season usually starts in December and ends in April/May of each year.
In order to minimize the bycatch numbers of marine turtles in these fisheries we are investigating the functionality of circle hooks versus normal J-shaped hooks. A circle hook is a hook which is sharply curved back in a circular shape. Circle hooks are less likely to be swallowed by turtles than traditional J-shaped hooks, which cause suffocation or internal bleeding when swallowed. Circle hooks are also easier to remove from a caught animal.
