There's a telling phrase for it: the tragedy of the commons. It happens because people think they can take a limitless amount of the earth's 'free gifts' such as the atmosphere or the sea or now, we are realizing, the fish.

For centuries these so-called 'global commons' have had no prices attached to them and so nothing to impose restraint on their use. Go ahead, take the atmosphere to dump your smoke in, take the sea to dump your effluent in. Fish to your heart's content, with ever more trawlers. It's all free.

And for centuries, nothing harmful happens, such is the seemingly limitless bounty of the Earth. But on a finite globe, the limits logically have to be reached at some stage, and yesterday's news that scientists are recommending banning all cod fishing in the North Sea means that time is now.

There are fish stocks in trouble all over the world. The most celebrated example is another cod stock, that of the Grand Banks off Newfoundland. When this fishery was discovered by French, Basque and later English fishermen in the 16th century, the cod were said to be so plentiful that a basket merely dipped into the water would be brought up brimming with fish. "You could walk on the backs of the cod," it was said.

For nearly 500 years the Grand Banks offered up their amazing harvest, until in the 20th century a sinister process began: the fishing effort began to outpace the ability of the fish stock to replace itself. It dwindled and dwindled, and then in 1989 it abruptly collapsed.

In 1992 the fishery was formally closed, throwing thousands of Canadian fishermen out of work; it has not reopened and it seems unlikely that it will.

It is the specter of this seemingly-permanent collapse which is clearly in the back of the minds of the specialists advising European fisheries ministers to call a halt to North Sea cod fishing right away. For a fish stock can make what is known as an "equilibrium shift"; it can change under pressure to a new level of stable numbers much lower than they were before.

Fish are not like wheat; you cannot simply sow them each year in the sea. Their population dynamics are complex and depend on a range of factors, not least the age at which they start to breed.

Cod typically start breeding at between four and six years old, but intensive fishing pressure may take out many of these bigger fish so that breeding slows down in a cumulative process, until virtually no new "recruits" to the breeding stock are coming through. This is what has happened off the east coast of Britain.

"We have stripped out the breeding cohort of cod from the North Sea," said Euan Dunn, the fisheries policy officer for the Royal Society for the Protection of Birds, and one of the closest observers of the workings – or non-workings, depending on your point of view – of Europe's Common Fisheries Policy (CFP).

"Cod stocks are in freefall now," Dr Dunn said. "Fishermen are catching more and more juvenile fish.

"The stock is at a historic low level owing to a combination of poor recruitment and very high fishing pressure, and this may be irreversible if very, very stringent measures are not taken."

International landings of North Sea cod have dropped from a peak of 341,000 tonnes in 1972 to a current low of only 41,000 tonnes. Cod, haddock and whiting in the North Sea are all described by the International Council for the Exploration of the Sea (ICES), the Copenhagen-based body which offers detailed scientific advice to the EU, as being "below safe biological limits", which means that recruitment into the adult stock is not sufficient to guarantee that the stock can be sustained.

Cod stocks are in a poor state right across the North Atlantic, and even Icelandic cod stocks are not as healthy as they were. The stocks have got so low that their dynamics are getting hard to predict, and the scientific models about what might happen are becoming less and less dependable. A further problem now being detected is the possible advent of global warming: as the sea waters warm, cod seem to be moving further north to cooler waters where they prefer to spawn.

But there appears to be no doubt that fishing pressure is the main threat. The European Commission has proposed a cod recovery plan for the North Sea which is due to be discussed and adapted by the fisheries ministers shortly, but it appears to be superseded by the stern advice from ICES, due to be published on Friday morning but already sent to governments: stop fishing now.

However there can be a wide gap between what scientists recommend and what fisheries ministers decide to do, and this gap points up the failure of the CFP.

The alarm is not new: the scientists have been sounding it for a decade and more. But over the 12 years from 1987 to 1999, officials of the European Commission in Brussels said earlier this month, EU fisheries ministers have set annual catch quotas on average 30 per cent higher than the scientists recommended.

Fisheries ministers tend to be vocal advocates for their national fishing industries, intent on merely getting as big a quota as possible for their fishermen every year, and disregarding the bigger picture and the warnings about shrinking stocks. Elliot Morley, the current British Fisheries Minister, has been a notable exception to the rule.

Their short-sightedness is now carrying over into opposition to reform of the CFP itself; France, Spain, Portugal, Ireland, Greece and Italy have set their face against proposed changes which would safeguard stocks by scientific limitation of fishing effort.

It is not hard to see why a fisheries minister listens to his fishermen rather than somebody else's scientists: livelihoods are at stake. Thousands of Scottish jobs are threatened by any North Sea cod ban. Peterhead is the biggest white fish port in Europe.

"These are really desperate straits for the Scottish industry, and if there is a ban it will be on its knees," Dr Dunn said.

But there cannot be an industry if there are no fish. What the CFP has not delivered is an industry that is sustainable.

"Fishermen can feel readily aggrieved that the European ministers as a whole have continued to sell the industry down the river by consistently avoiding scientific advice," said Dr Dunn.

Thirty years ago the Club of Rome, a group of economists with a radical new take on the mushrooming growth of the word economy, sounded the first warnings about the Earth's natural resources running out.

Some of the fears then voiced, it was later shown, were groundless. Far from oil running out, there are more oil reserves available now than there were in 1970, despite all the consumption of the intervening years. But with fish it may be different.

Unless stocks are managed tightly by all concerned with them they may well collapse, and soon, and the first tragedy of the commons will have been played out.

Fishermen's blues

On the windswept quays of Peterhead, the largest white fish port in Europe, the mood of the trawlermen yesterday chimed with the ancient burgh's nickname of "the Blue Toon".

For many of the deep sea fishermen whose families have fished the icy waters of the North Sea for generations, the proposals put forward by EU scientists calling for a ban on cod and haddock catches mean the end of a way of life.

More than 100,000 tons of fish worth more than £80m are landed each year at Peterhead's four harbors, which are home to about 865 fishermen and one of the most modern fish markets in Europe.

"This would mean financial ruin for me and every other fisherman," said George Geddes, the skipper of the Peterhead-registered Scotia, who employs five men on the boat and provides work for up to 25 others onshore.

Agnes Strachan, a local councilor, said: "This ban would kill Peterhead ... everybody here relies on the money created from the fishing."

Since about AD55 this corner of north-east Scotland has been indelibly entwined with the sea and the harvests of white fish that helped to create Peterhead in 1587. Situated 32 miles north of Aberdeen, the town now has a population of less than 18,000.

© 2002 lndependent Digital (UK) Ltd

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