The pilot scheme is aimed at conserving fish stocks

The joint initiative developed by the industry and the Scottish Government was launched earlier this year.

Under the initiative, skippers are given extra days at sea if cod forms less than 5% of their catch. The scheme will now cover larger juvenile fish.

Skippers sound the alert when they encounter stocks of small cod.

Rural Affairs Secretary Richard Lochhead said: "The new Scottish Government pledged a fresh start for Scottish fisheries and I am very pleased that this fresh thinking has already reaped rewards. This scheme is the first of its kind in Europe.

"Reports from the industry so far show that vessels have been actively avoiding areas where undersized cod are likely to be in abundance. These responsible actions have resulted in no need for a formal closure to date.

'Sustainable fishing'

"There will be a full evaluation of the pilot at the end of the year."

Mr Lochhead added: "These responsible actions by Scotland's fishermen allow us to be in a position to extend the scheme for the last two months of the pilot to help safeguard the future breeding stock of North Sea cod."

Bertie Armstrong, chief executive of the Scottish Fishermen's Federation, said: "It is important to see this measure as one strand in a whole bundle of positive, proactive initiatives to make sure that the cod recovery now under way takes real hold.

"Innovative changes to net components, verification of cod avoidance by use of an observer programme and development of coherent strategies by area are all part of the Scottish fishing industry's much wider approach to sustainable fishing."