Sir: In a week that has seen headlines ranging from ‘booming cod stocks in Norway and Iceland’ to ‘cod will vanish in 10 years’, the real question is what to believe (‘10 years left for cod and chips? What a load of codswallop’ 16 June).

The Grocer rightly pointed out the good news on Atlantic stocks and Barents Sea cod. A consequence of good management is that we may indeed be catching less cod than in the 1960s, and that is perhaps why Iceland is experiencing its highest stock levels since the 1970s.

There are reports that ‘85% of world fish stocks are fully exploited, over-exploited, depleted or slowly recovering’. What is wrong with fully exploited? It means stocks are being fished to their maximum sustainable capacity.

Adding to the confusion, scientists use the term ‘overfished’ for stocks being fished above maximum sustainable yield. To explain, a stock may be overfished, because fishing is not at the optimum rate for maximum sustainable yield, but still within safe biological limits.

So rarely applauded is the progress the industry has made in Europe. In 2008, 32 out of 34 stocks were classed as overfished, which dropped to 18 out of 38 in 2011 - considerable progress. We have more to do, but let’s encourage this, rather than denigrate.

Dr Jon Harman, operations director, Seafish