Current target for sustainable fishing involves unnecessarily high risks

How much can we fish without jeopardising the future of our fish stocks? Within ICES, the benchmark FMSY is used to define the level of fishing pressure that, according to current models, should deliver the highest possible long-term catches while keeping stocks healthy.

In the study, the researchers compared the method ICES currently uses to calculate FMSY with an alternative model that takes uncertainty in stock data into account.

–The results clearly show, that fishing at FMSY is not precautionary. When we consider the uncertainty in stock assessments, the risk is higher than allowed under the precautionary approach in three of the four stocks analysed, says Massimiliano Cardinale, researcher at SLU and co-author of the international study.

The study also shows that reducing risk does not require major cuts in fishing pressure.  When fishing pressure was set to around 60 percent of today’s FMSY, long-term catches decreased by only about five percent, while the risk of stocks falling to critically low levels, dropped sharply and the biomass of adult fish increased substantially.

– Given the large uncertainties in fish stock data, it is time to change how FMSY is used within ICES. Our results show that FMSY works better as an upper limit that should not be exceeded, rather than a target to reach. Aiming for maximum catches is not reasonable when the uncertainty is this high, says Massimiliano Cardinale.

The study, published in ICES Journal of Marine Science, is based on analyses of four fish stocks in the Northeast Atlantic that were recently benchmarked within ICES. Because the method reviewed in the study is widely used in ICES advice, the researchers consider the results to be relevant for many more stocks than those included in the analysis.

The article The ICES MSY approach to reference point estimation is not precautionary has been published in ICES Journal of Marine Science.

It is important to note that reference points currently used for Central Baltic herring, Gulf of Bothnian Sea herring and Northern shrimp are derived using the same alternative tool  highlighted in the paper and thus are precautionary.