Closing the high seas to fisheries: Possible impacts on aquaculture

Consumption of seafood has increased steadily over the past several decades and this trend is expected to continue with projected increases in global population and affluence. Wild capture fisheries catches have likely reached their peak, and therefore any significant increase in future fish supply is expected to come primarily from aquaculture. However, aquaculture continues to rely on wild stocks by using fishmeal to support culture of fed species. Recently, concerns regarding wild fish populations have led to calls for the closure of the high seas (i.e., international waters) to fishing. Such a policy would decrease marine fish catch in the short term while potentially increasing future catch. Here, we assess the potential impacts of closing the high seas to fishing on marine fish catch that goes to reduction into fishmeal. We quantify the potential effects of these changes on the price of fishmeal and profitability of the global aquaculture industry. Not surprisingly, we find a stronger effect of closing the high seas to fishing for high-value carnivorous species such as shrimp and salmonids. Overall, however, our study suggests that the impact of closing the high seas to fishing on aquaculture is likely to be insignificant.