Once cast aside by fishermen or sold off as bait for far more sought-after seafood, the red gurnard is enjoying a stratospheric rise in popularity.

Gourmets across the country are seeking out the previously unappreciated white fish in vast numbers, pushing up its price from 25p to £4 per kilo.

The secret of its success has been the patronage of such well-known fish experts as the chef Rick Stein who has been extolling its virtues for years as an alternative to over-fished cod and haddock. Together haddock, salmon, cod, prawns and tuna account for 70 per cent of the fish sold in this country. But the power of the celebrity chef is unquestioned and many have encouraged readers of their recipe books to broaden their horizons.

In his new book, Rick Stein's Mediterranean Escapes, the TV chef has included a recipe for red gurnard in sweet and sour onions. However he pointed out yesterday that he had become a victim of his own success.

"I have always liked red gurnard but the slight problem is that it has become rather expensive. It is causing us some concern in the restaurant. It is getting quite pricey," he said.

His customers and readers, he explained, were getting increasingly brave in their choices and picking alternatives to cod such as pollack and ling.

"It is just a question of giving them the right recipe, the right application and then people are very happy. Ling and pollack are not that big a leap. They are quite similar to cod."

A survey of 1,200 consumers by the Seafish Marketing organisation found that 80 per cent were aware of over-fishing as an issue and 64 per cent said they would be prepared to try something new. Last year the Marine Conservation Society produced the Good Fish Guide encouraging consumers to conserve fish stocks and suggesting red gurnard as an alternative.

"Back a few years and gurnard was an unwanted part of the catch. But people have discovered it is actually very tasty," said Paul Trebilcock, of the Cornish Fish Producers Organisation.