Ninety per cent of fish in the waters around Britain will have disappeared within 20 years unless they are given protection, a leading marine researcher told scientists yesterday.

Professor Callum Roberts claims that “the endgame” was being played out with the remaining fish in the seas and that they are doomed without radical measures to save them. The number of fish in seas and oceans around the world was a fraction of what it had been 50 years ago, and numbers were still plummeting.

He told the British Association for the Advancement of Science conference in York that fishing quotas needed to be scrapped and extensive no-fishing zones put in place. He also said that fishing should be halted or strictly limited in a third of Britain’s seas to give stocks time to recover. Fishing ministers, who are said to have disregarded scientific advice on sustainable fishing levels over the past two decades, should be stripped of their powers to rule on how many tonnes can be safely caught, he continued. They would be replaced by a science-led body that is independent of electoral pressures.

The decline in fish stocks around the world, with all species predicted by some experts to collapse by 2048, comes at a time when their nutritional value is recognised more than ever. World Health Organisation officials recommend a weekly intake of 200 to 300 grams of fish each week but today’s catches can only just meet this target.

“If we don’t act now to change the way we fish we will be writing the requiem for the sea. Without conserving stocks there won’t be any fish,” Professor Roberts said. “Twenty years from now the sea will be yielding very little if we don’t change the way we do things. It will be 90 per cent collapsed around Britain. We are playing out the endgame of fishing.”

Measures have to be taken, he said, to reduce fishing capacity, particularly to stop bottom-fishing trawlers ploughing up and destroying the ecosystem on the sea bed, but creating no-fishing zones is the priority.

He told the conference: “On average, over the last 18 years fisheries ministers have set quotas 20 to 30 per cent higher than recommended as safe. If we continue to do that a majority of fish stocks will collapse.”

Since the 1950s an estimated 60 per cent of stocks in British waters have collapsed and he said that more than half of those remaining are already being dangerously overfished.

“One of the most important reforms is to take the decision-making powers away from the politicians,” he said.

The European Commission recognised in a recent policy report that four-fifths of European stocks are being overfished. Only haddock and saithe in the North Sea and megrims in the Bay of Biscay are being fished according to sustainable commitments. The report said that the failure to set quotas in line with scientific guidance was a “high risk” strategy. “The stocks are not showing a tendency to recover or to increase inside safe biological limits – rather, the industry continues to be in a high-risk situation,” the report added.

The future for fish is equally bleak across the rest of the world, the conference was told at the paperback launch of The Unnatural History of the Sea, written by Professor Roberts.

“If we don’t change the way we do things the prediction is all of the species we exploit could well collapse by 2048,” he said.

The findings from the research into stock levels by Professor Roberts were bleaker than the assessment by the government but officials recognise that there are threats to marine life.

According to the Department for Environment, Food and Rural Affairs (Defra) only 25 to 30 per cent of fish stocks around Britain have been fished sustainably since 2001. “This means that around 70 per cent of UK fish stocks have suffered reduced reproductive capacity and have been harvested unsustainably since 2001,” a Defra report stated, accepting that the scientific advice “is that the fishing rate should be reduced substantially in order to permit the stocks to recover”.

A drop in the ocean

Fall in species since 1850:

Cod 98%
Haddock 90%
Plaice 90%
Whiting 70%
Halibut 98%
Turbot 95%

Disappearing: common skate no longer viable fishery angel shark last seen in 1980s conger eels very scarce and in steep decline wolf fish very scarce and in steep decline round-nosed grenadier 90% fall since the 1970s

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