SCOTTISH fishermen have voiced concerns at a downgrading of haddock in a new guide by the Marine Conservation Society which they fear will affect consumer behaviour.

Haddock from three North Sea and West of Scotland fisheries are no longer on the charity’s recommended ‘‘green’’ list of fish to eat, having been downgraded because stock numbers in 2016 were below the recommended level.

The Scottish Fishermen’s Federation (SFF) said fish stocks in the area are well-managed at sustainable levels.

SFF chief executive Bertie Armstrong said: “The MCS has completely misunderstood the position as far as haddock stocks are concerned and should withdraw its utterly misleading comments.

“The organisation is trying to alter consumer behaviour on completely false premises.

“Fish stocks are sustainable when the amount of fish caught is below the maximum sustainable yield. For haddock that has been since 2007 - and last year advice from fisheries scientists at the International Council for the Exploration of the Seas (ICES) was for an increase in the catch of 30 per cent.

“They then discovered that there had been an error in their assessments, corrected the statistical model and recommended a reduction in the catch of 45 per cent, which was adopted. The fishery continues to be managed at sustainable levels, and the spawning stock for haddock will increase significantly in 2018.”

International conservation body, The Marine Stewardship Council (MSC), which certifies the sustainability of fish and seafood also gave its backing to Scottish North Sea haddock and contradicted the MCS advice. It insisted consumers can enjoy haddock suppers with a “clear conscience”.

MCS spokesman James Simpson said: “The Scottish haddock fishery is still MSC certified due to the strong management they have in place to deal with changing stocks.

“The fishermen have already worked with the government to set lower quotas in response to the latest scientific advice. In fact they’ve set their catches even lower than the recommendations. It’s a bold move to protect the haddock stock for the long term.

The Marine Conservation Society, however, said it had not called for haddock to be taken off menus, which it only does with fish with an “avoid” high score of five.

It added that ratings for North Sea and West of Scotland haddock are rated three and four in its guide.

A spokeswoman said: “The new ratings for North Sea and West of Scotland haddock are three and four. The new ratings come after the latest scientific advice from ICES which was released in November last year.

“This advice indicated that the levels of fishing that can be considered sustainable for this population are lower than previously thought, meaning a smaller proportion should be caught. This means that advice for catches in 2017 are 47 per cent lower than originally advised for catches in 2016.

“Latest quotas have been reduced in line with this scientific advice, and the biomass is expected to significantly increase this year.

“Contrary to some suggestions, consumers should not expect to see a shortage of haddock in shops.

“A new assessment will be undertaken later this year, when new ICES advice becomes available, and if the health of the fishery has improved as expected, this will be reflected in MCS ratings.”