A technological transformation contributes to the conservation of the ocean.

Replacing hooks and better turtle handling

Of the different approaches to mitigate the by-catch impact of long-line fishing, the replacement of the traditional J hooks by "circle" hooks along with better handling of marine turtles is the most promising.

Replacing J hooks by "circle" hooks can reduce actual by-catch rates by up to 90% and in some cases such as tuna fisheries, "circle" hooks can even increase target catch rates. "Circle" hooks catch animals most frequently around the mouth, avoiding fatal injuries to fish and turtle.

It is also necessary to work with fishermen, convincing them to become more proactive in activities concerning turtle conservation. This can be achieved by showing them proper de-hooking techniques, onboard turtle treatment and recovering techniques, to be applied before releasing the turtles back to the sea.

Latest Results

Working with the fishing industry - Earning their trust

/ ©: Carlos Miguel Imbach
Fishing boat, Puntarenas, Costa Rica.
© Carlos Miguel Imbach
Marine turtle by-catch mitigation in long-line fisheries is being accomplished through a collaborative project with the fishing industry and artisanal fishermen in the Eastern Pacific Ocean.

Fishermen are trained in the correct use of "circle" hooks, meant to substitute J hooks, and on best fishing practices to correctly recover and release unharmed hooked turtles. Proper manipulation and motivation of fishermen is key to increase the benefits already provided by circle hooks as means to mitigate by-catch.

The model shows real life evidence of the benefits of the gear substitution , and consists in educating and training fishermen in by-catch mitigation techniques, and the performance of voluntary fishing experiments, with onboard observers, to test "circle" hooks against J hooks.

This model seems to fit perfectly fishermen’s cultural and social process of adopting new fishing practices and it is backed up by recognition and trust from fishers.

Onboard Observers program - Data Collection

/ ©: Alvaro Segura
Observers also release hooked and entangled turtles and train fishermen in better fishing practices.
© Alvaro Segura
Onboard observers are recruited by the program mainly in fishing ports and receive training in species identification, turtle manipulation techniques, data sheets filling, and responsibilities onboard. They collect important information from the fishing trip, including fishing gear structure, sets, fish catch and turtle by-catch. Data is later reviewed and entered into a regional database for later statistical analysis. Observers also release hooked and entangled turtles, and train fishermen in better fishing practices.

Ultimately, the observer program is the platform to tackle issues of governance and fisheries management with the direct involvement of the fishermen. More than one hundred observers are currently working in the program and have contributed with 1,200 fishing trips since 2004.

Testing of circle hooks

/ ©: Laura Sequeira
The testing of circle hooks is fundamental to develop statistical evidence on their effect.
© Laura Sequeira
Fishing vessels in each country are testing different types and sizes of "circle" hooks depending on the fishery characteristics, following an experimental design that should provide statistical evidence on the effect of the hooks with regards to sea turtle hooking rates, target catch rates and location of hooking. Up to now more than 1,000,000 circle hooks have been used and tested by long-line fishing vessels at sea.
  • / ©: WWF
  • / ©: WWF

Subscribe to our mailing list

* indicates required
Find out more about tigers, one of the mos iconic species of our planet.

see all WWF gifts

Building a future in which humans live in harmony with nature.

Photos and graphics © WWF or used with permission. Text available under a Creative Commons licence.