Closing the high seas to fishing could improve the distribution of catches globally according to a study in Scientific Reports this week. The findings are based on estimates of fish stocks caught in coastal areas and the high seas, although a number of factors could cause uncertainty in these data. Thus, additional detailed analyses of the costs and benefits of high-seas closure are warranted.

Fishing takes place within exclusive economic zones, which are generally managed by the local coastal countries, and in the high seas, which are considered international waters and therefore ‘shared’ by all countries of the world. The increasing exploitation of fish on the high seas has raised concerns about species or habitat destruction and the potential economic impacts of fish-stock depletion, prompting proposals to close the high seas to fishing. To assess how this scenario may alter global fisheries catches and values, U. Rashid Sumaila and colleagues assess the overlaps between fish caught in the high seas and coastal areas. They estimate that around 42% of commercial fish straddle both environments, and predict that closure of high seas will result in more of these fish being caught in coastal areas. The authors note that while some countries may experience losses, most coastal countries stand to benefit, including the world’s least developed countries, and there would be an overall net gain in catches worldwide.