How Do We Know If Tuna Is Running Out?

Tuna fishing is a global industry, but how do we actually know if we’re catching too much?

Every time you eat tuna, you’re relying on a system most people have never heard of: stock assessments. These scientific models estimate how many fish are in the ocean, how fast they reproduce, and how much can be caught without causing long-term damage.

Stock assessments are not about counting every fish, they’re about making the best possible decisions with imperfect data. Scientists use catch records, fishing effort, and biological information to understand whether tuna populations are healthy or at risk. But the science is only part of the story.

In this episode, we break down how tuna stock assessments work, why they are critical for sustainable seafood, and how organizations like ISSF help ensure that decisions are based on science, not just politics. You’ll also learn how past failures shaped today’s system, and why the future of tuna depends on getting these calculations right.

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