Sir

The threat of overfishing to world fisheries is well documented, but not enough attention has been paid to government subsidies as an important factor in their decline. Subsidies, or government payments to the fishing sector, estimated at US$30–34 billion a year, are key drivers of the unsustainable exploitation of the world's depleted fish populations. Fish are the main source of protein for one fifth of the world's population, but global fishing fleets are more than double the size the oceans can support.

If fisheries are to become sustainable, overfishing subsidies must be significantly reduced (U. R. Sumaila et al. Fish. Res. 88, 1–4; 2007). Unfortunately, unilateral action by individual countries may not work, because their fisheries could then be at a disadvantage in the competitive global market for fish; also, fish do not respect national boundaries and fishing fleets operate worldwide. The only effective approach to the subsidy problem is through multilateral action, in which all fishing nations end or reduce these subsidies under similar rules.

The World Trade Organization (WTO) has 151 member countries and a mandate to level the trade playing-field for every country. It is in a unique position to tackle the global problem of overfishing subsidies and to move fisheries towards sustainability, because it is the only global institution, apart from the Convention on International Trade in Endangered Species of Wild Fauna and Flora, that has mechanisms in place to enforce its agreements.

The WTO is at present drawing up terms, including terms on how to police fisheries subsidies, in the Doha round of negotiations. We urge the WTO to seize this opportunity now, to forestall the predicted collapse of the world's wild fish populations.