Pew Press Release: Western Atlantic Bluefin Tuna in Decline, New Action Needed
Thursday, July 30, 2020, 15:00 (GMT + 9)
Yesterday, the International Commission for the Conservation of Atlantic Tunas (ICCAT) wrapped up its stock assessment for western Atlantic bluefin tuna, and the results are concerning.
In 2017, after early signs of an increasing population size, ICCAT managers adopted catch limits that scientists advised would lead to a decline. This is exactly what happened.
Projected total stock biomass under alternative constant F scenario (F=F0.1) for the 2017 base VPA and SS model results combined; y-axis shown from 32,000 to 38,000 t. Current (2018-2020) TAC is 2,350 t. (Source: 2019 SCRS REPORT/ICCAT)
- The 2020 assessment results for western Atlantic bluefin suggest that the stock has declined in recent years to just 13% of the 1950 level.
- If the current quota of 2350 metric tons remains, there is a 94% chance of overfishing in 2021 and a 96% chance in 2023.
- Perhaps most significantly, the decline in the western stock could be masked by mixing with the eastern stock, which is rebuilding stronger.
- To have a more than 60% chance of not overfishing, the catch limit needs to decrease to 1750 metric tons in 2021, 1700 metric tons in 2022, and 1650 metric tons in 2023. But even those catch limits would lead to further stock decline. To prevent this, the catch would need to be below 1000 metric tons.
Grantly Galland, an expert from The Pew Charitable Trusts’ international fisheries noted the following:
“In 2017, after early signs of potential population growth, ICCAT governments – including the United States and Canada – prematurely abandoned their 20-year recovery plan for western Atlantic bluefin tuna and adopted a catch limit that scientists had advised would cause decline. Now, as predicted, the population is shrinking again.
“This stock assessment makes clear that ICCAT should be less risky, and that the United States’ recent loosening of protections for western Atlantic bluefin in the Gulf of Mexico was premature. Western Atlantic bluefin needs increased conservation efforts and improved management immediately, beginning with a reduction in catch level and renewed commitment for a more precautionary management system.”