Addressing illegal fishing could provide an easier and cheaper route to sustainable fisheries than relying solely on curtailing legal fishing, according to research published online this week in Nature Ecology & Evolution.
Overfishing threatens biodiversity, food security and livelihoods, but addressing it requires short-term reductions in catch and profits, making many countries reluctant to take decisive action. Adding to this burden is illegal, unreported and unregulated (IUU) fishing, which constitutes about 20% of the global fish catch. Most IUU fishing in a given country’s exclusive economic zone is conducted by foreign vessels. Some countries have made considerable efforts to reduce IUU fishing in their waters. Indonesia, for example, has destroyed fishing boats, banned foreign vessels, and restricted transfers between boats at sea. The impact of these types of efforts on stock sustainability, however, has not been investigated.
Reniel Cabral and colleagues studied the efforts to halt illegal fishing of the skipjack tuna fishery in Indonesia using satellite tracking, vessel monitoring data, and bioeconomic modelling. They found that the time foreign boats spent fishing in Indonesian waters declined by 90% with the restrictions, and the number of fishing boats overall decreased by 30%. While this reduction was met by increased domestic fishing, the author’s bioeconomic model suggests that, if domestic fishing is capped at its maximum sustainable yield and illegal fishing is tackled, catch and profits could increase by 14% and 12%, respectively, compared to decreases of 15% and 14% if illegal fishing is left unchecked.
The authors found similar trends in The Gambia, and suggest that reducing IUU fishing could provide a simple and cost-effective route to sustainable fisheries globally. They also highlight the importance of satellite and publically available government data to tracking and stopping IUU fishing.