Both the United States and the European Union import 70 percent of their seafood. Most of it comes from the 200-mile Exclusive Economic Zones of West and East African countries, and from island countries in the Central and South Pacific, where European fleets operate in competition with fleets from East Asia, notably China. Some of this fishing is illegal, but much is done under legal “partnership agreements” with local governments. These countries get a fraction of the value for the use of their offshore resources, while the scale of the catches puts their food security at risk.

The United Nations Food and Agriculture Organization reports that the size of the annual world catch since the 1990s is either stagnating or slowly declining, at great cost to society and to marine ecosystems. This trend is undercutting recent progress. Fishing grounds off the United States are being replenished, owing to the passage in 1976 of the Magnuson-Stevens Act, which took aim at the twin scourges of overcapacity fueled by government subsidies to the American fishing fleet, and the subsequent overfishing of depressed stocks. Meanwhile, the European Parliament, under pressure from consumers, environmental organizations and maritime scientists, adopted a series of measures last year that could, if implemented, have similar positive results. These include:

•Enforcing new catch limits so that fish population levels should, by 2020, recover, enough to generate the “maximum sustainable yield” called for under the United Nations Convention on the Law of the Sea.

•Phasing out the discarding at sea of unwanted fish, which often involves half or more of the catch of edible fish. This is a huge problem, since discarded fish are not recorded, and thus not taken into account when setting quotas.

•Protecting biodiversity by incorporating local stakeholders into the management of ecosystems.

•Paying greater attention to monitoring the huge European fleets operating in the waters of developing countries.

These proposals can still be blocked or undermined. Industry lobbies and the threat of lost jobs have prevented a reduction of the government subsidies — loan guarantees for purchasing new engines, electronic fish-finders and other technologies — that contribute so much to overcapacity. Powerful forces, like the Comité National des Pêches Maritimes, argue that implementing the stock-rebuilding mandate, phasing out the practice of discarding, and other measures would ruin the industry.