Leading article: We will pay a steep price for our plunder of the oceans

Once again, the annual round of quota haggling between European Union fisheries ministers has put the short-term interests of the fishing industry above the long-term interests of sustainable fisheries. Scottish and English fishermen lobbied hard in the run-up to these talks for a higher quota for North Sea cod. They have been successful. It was announced yesterday that there is to be an 11 per cent rise in the permitted North Sea cod catch in 2008.

The deal has been welcomed as "fair" by the British fisheries minister, Jonathan Shaw, and hailed as "sustainable" by Richard Lochhead of the Scottish executive. One wonders where these two politicians are getting their information from. It is simply wrong to argue that North Sea cod stocks have recovered. Estimates might have shown a small increase in the past two years, but they are still only a quarter to a third of the EU's rebuilding target. Far from recommending an increase in the cod catch, the International Council for the Exploration of the Seas advised a 50 per cent reduction.

If we continue to plunder North Sea cod fisheries, they will go into terminal decline. This is not scaremongering. That is precisely what happened to the cod fisheries off the Canadian Grand Banks in the 1990s when politicians and fishermen ignored the scientific warnings about over-fishing. If this happens in the North Sea, the fishermen presently complaining so bitterly about their income, will find their very livelihoods destroyed.

One of the complaints of the fishermen is justified. It is quite true that the present EU quota system is not working. The limits imposed on the amount of fish that vessels can bring back to port (but not the amount of fish they actually catch) is having a counter-productive effect. Some 800,000 tonnes of fish caught by trawlers in the North Sea are being dumped back into the sea. Mr Shaw is right to call this wasteful and immoral. It also destroys the environmental goals of the quotas. But the solution is not to allow fishermen more time at sea or bigger catches. It is to leave the fish alone in the first place.

It should be stressed that over-fishing is by no means exclusively a European problem. A major international scientific study of the seas last year argued that, if present rates of fishing continue, there will be virtually nothing left to fish from the world's seas by the middle of the century. Stocks have collapsed (defined as a decline to less than 10 per cent of their original yield) in one third of sea fisheries. And the rate of decline is accelerating. Bigger vessels, better nets and new technology for spotting shoals are not bringing in bigger returns. In fact, the global catch has fallen by some 10 per cent since 1994.

There is hope. Data from areas where fishing has been banned, or heavily restricted, show that fish stocks and marine diversity can recover given time. We need to create large non-fishing zones in areas where fish stocks are under severe stress. If we cut the global fishing effort in half, it should create the space for stocks to rebuild themselves.

But our political systems are failing to deliver. Over the past 20 years, EU ministers have exceeded safe catch recommendations from scientists each year by an average of 15-30 per cent. And this year's deal for all its emphasis on new "conservation credits" is just as bad. We are faced with a simple choice. We can give our fish stocks time and space to recover something that will enable us to increase our harvest from the seas over time. Or we can continue down the present road which will lead inexorably to oceans denuded of fish.