ISSF supports multiple initiatives to help track and mitigate the bycatch of sea turtles, especially in longline fisheries. Many sea turtle populations are in decline, including from fishing pressure, and species are protected by national and international treaties and regulations.

Sea Turtle Bycatch

When sea turtles are incidentally caught in purse-seine fisheries, their mortality is low: more than 90% can be released alive into the water. 

In longline fishing, sea-turtle bycatch rates and survival are greater concerns — and a priority for ISSF and other NGO conservation efforts.

Common Sea Turtle Species in Tuna Fisheries

  • Green sea turtles (Chelonia mydas)
  • Hawksbill sea turtles (Eretmochelys imbricata)
  • Loggerhead sea turtles (Caretta caretta)
  • Olive ridley sea turtles (Lepidochelys olivacea)
  • Leatherback sea turtles (Dermochelys coriacea)


Turtle Nesting Projects

Among the strategies to help protect sea turtle populations, nesting conservation projects can have one of the largest positive impacts.

Nest destruction represents an additional mortality threat to sea turtles and has many causes, including:

  • Over-harvest of eggs for human consumption
  • Predation by feral pigs and dogs
  • Habitat degradation due to development, deforestation, pollution, and other human activities

ISSF supports sea turtle research, conservation, and educational projects worldwide — including in Brazil, Tanzania, Peru, and Oman — through a $100,000 annual fund created by several ISSF participating companies: Bumble Bee, Thai Union/COSI, TriMarine, and StarKist.

Bycatch Prevention Strategies

Tuna fishers can modify their gear and fishing practices, through “passive mitigation” approaches, to reduce the risk of incidentally catching sea turtles.

Longline fishers, for instance, can reduce sea turtle interactions by using wide circle hooks and fish bait to attract tuna, and set hooks at certain depths.

To avoid turtle entanglement in netting from fish aggregating devices (FADs), fishers should use only non-entangling FAD designs. Our Non-Entangling & Biodegradable FADs Guide illustrates how to build FADs without netting.

Bycatch Handling & Release Techniques

To help researchers identify and disseminate best practices in sea turtle handling and release, longline tuna fishers and observers have shared their knowledge on effective tools and approaches in ISSF-sponsored workshops.

In ISSF guidebooks, infographics and posters, and scientific reports, we outline steps that fishers can follow to safely untangle or de-hook sea turtles, monitor their rest and recovery on deck, and release them into the water.

We also have compiled turtle species identification resources by ocean.

RFMO Advocacy

To inform Regional Fisheries Management Organization (RFMO) requirements for fleets, ISSF shares science-based recommendations to mitigate sea turtle bycatch through an array of outreach efforts — including position statements to guide RFMO policy discussions.

We also evaluate RFMO FAD management measures, including FAD recovery policies to prevent ghost fishing, that can help to protect sea turtles.







Species Identification Guides

The ISSF Guidebooks site contains guides, in several languages, to help fishers identify different species of tuna.

We also offer identification guides for bycatch species such as sharks, rays, billfish, sea turtles, seabirds, and non-tuna finfish.

Sea Turtle Handling Videos

On our YouTube channel, we offer sea turtle videos for longline fishers in several languages.

These videos demonstrate techniques to safely remove fishing hooks from incidentally caught sea turtles to give them the best chance of survival.

Non-Entangling & Biodegradable FADs Guide

Tuna fishers that rely on Fish Aggregating Devices (FADs) to make their catch can significantly reduce the risk of entangling sharks and other animals by not using netting.

Our guide illustrates how to build FADs that not only avoid netting but also incorporate natural, biodegradable materials in place of traditional plastic or other man-made components.

We publish the guide in several languages.

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