All tuna fishing methods have some degree of impact on the marine environment, including on other species, such as sharks, sea turtles, rays, and seabirds.
ISSF researches, identifies, and publishes science-based best practices — often in collaboration with commercial tuna skippers — for mitigating bycatch. Bycatch is the catch of any species that is not the main reason for which the skipper is fishing, whether the catch is retained or discarded.
To help fishers avoid unintentional catches of non-target species, our scientists investigate changes in fishing gear and other methods, including aspects of fish aggregating device (FAD) design and management. We also test and refine safe handling-and-release techniques that skippers can use when marine animals are accidentally caught.
Many seabirds in tuna fisheries are endangered — and at risk of harm from baited tuna-fishing hooks. Our longline skippers guidebooks show fishers how to avoid attracting and hooking them.
In our scientific reports, we publish data and analysis on a range of bycatch issues — from summaries of our at-sea research projects, international workshops, and collaborations with skippers to bycatch rates by fishery type and species-specific bycatch mitigation procedures. We also have explored the market retention of non-target species caught as bycatch.
ISSF is researching how acoustic discrimination of tuna species at FADs, using echosounder technology, may help fishers to more precisely target certain tuna species and avoid catching bycatch species. Our scientists publish their findings in peer-reviewed articles.
Watch our videos for an introduction to our bycatch research.
As we identify key challenges in and potential solutions for reducing bycatch of all species in tuna fisheries worldwide, we create conservation measures to address them.
Fisher Collaboration & Education
To support skippers in protecting sharks and other bycatch species in tuna fisheries, we offer bycatch-education opportunities and resources:
- In-person and video versions of skippers workshops conducted by ISSF scientists and consultants
- Online and downloadable guidebooks on sustainable fishing and species identification guides
- Videos, posters, and infographics showing “do’s and don’ts” for handling and releasing entangled or hooked non-target species
We also share research about set times and technology that can help vessels to fish more selectively and minimize unintentional catches.
We turn our scientific insights about sustainable fishing approaches into conservation and policy recommendations for Regional Fisheries Management Organizations (RFMOs), governing bodies, and other oversight agencies.
For instance, our advocacy experts develop position statements to petition RFMOs about bycatch-mitigation requirements for fleets in their ocean regions. We recommend steps RFMOs can take to make their measures align with best practices, and we assess their progress.
We also circulate joint letters to RFMOs, co-signed by seafood companies, retailers, and environmental organizations.
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.
Species Identification Guides
The ISSF Guidebooks site contains guides, in several languages, to help fishers identify different species of tuna.