An eco-labelling scheme intended to encourage people to eat fish from sustainable sources is being criticised by conservationists.

The collaboration between the conservation group WWF and Unilever, until recently one of the world’s biggest seafood retailers, now gives its stamp of approval to $1.5 billion (£900 million) of business every year. There is concern, however, that the scheme’s blue label, which is put on packaging, is being awarded to fisheries whose stocks are not properly managed or where the ecosystem is being damaged.

The scheme was established ten years ago by the Marine Stewardship Council (MSC), based in London. There are 58 certified fisheries, with a further 114 in the process of being assessed. It is intended to benefit fishermen by ensuring long-term sustainability of their livelihood and boosting the price of their catch.

The source of the New Zealand hoki — a bug-eyed, deep-water fish once used for McDonald’s Filet O’Fish — was one of the first fisheries to be certified in 2001. Stocks promptly crashed and quotas were slashed from 250,000 tonnes to just 90,000 tonnes by 2007.

While the hoki industry cites the reduced quotas as a sign of pre-emptive good management, conservationists say that they are a sign of underlying problems with the science of how stocks are judged sustainable.

At the other end of the Pacific, the same argument rages over the pollock used to make many of Britain’s fish fingers. The MSC-certified Alaskan pollock fishery is worth nearly $1 billion a year, but despite being rigorously managed by the National Marine Fisheries Service the stock’s assessments are controversial. Populations appear to have halved since 2004, and last year quotas were cut by nearly 20 per cent. Jeremy Jackson, of Scripps Institution of Oceanography in San Diego, California, said: “Economic pressures to keep on fishing at such high levels have overwhelmed common sense.”

The MSC prides itself on its transparency and well-regulated objections process, but there are signs that it is not fulfilling its function. Southeast of the pollock grounds, the Pacific hake fishery was in the closing stages of certification earlier this year. The Monterey Bay Aquarium and Oceana, a marine conservation group, filed an objection, pointing out that the stock was at the lowest level ever observed, down nearly 90 per cent from the 1980s. The claim was dismissed.

To date, no objections have resulted in a rejected application. Only one fishery — for lobsters, in British waters — has been turned down after an assessment has been paid for The MSC uses independent companies to assess fisheries, which critics say leaves the door open to “special arrangements” between them and the fishing companies which pay to be evaluated. The fees are typically between £9,000 and £72,000.

Moody Marine International does about half of all MSC certifications around the world. Like the other certifiers, Moody will provide fisheries with a pre-assessment to assess their likelihood of being accepted. But as Andrew Hough, one of Moody’s lead assessors, admits, “as the market has increased, far more enquiries we get now lead to pre-assessment, and most of those lead to full certification”.

“I wouldn’t say they’ve all come out smelling of roses ... Each fishery has some area of weakness,” he said.

A report by Consumer Focus, formerly the National Consumer Council, adds to criticism of the scheme today, saying it is not convinced supermarkets give the information shoppers need to decide whether fish are from sustainable stocks.

“In theory certification is a great idea, but this scheme has never fulfilled its potential,” said Barry Weeber, of the Deep Sea Conservation Coalition. “The bar has always been set far too low.”

Rupert Howes, CEO of the MSC, said: “Fisheries science is an evolving business. At some stage in the future standards will be reviewed. In the interim, don’t let expectations of perfection obscure the significant progress that is being delivered.”

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