THE first-ever Marine Conservation Order (MCO) has been issued to protect a delicate underwater site in South Arran.

The move, which will protect fragile ecosystems in the Firth of Clyde, comes after fishermen breached a voluntary agreement not to trawl the important site.

It has been welcomed by environmental campaigners, who say the breach demonstrates that more formal measures are needed to protect the country's 30 Marine Protected Areas, including South Arran.

Calum Duncan, Scotland Programme Manager for the Marine Conservation Society, said: "While it's unfortunate that the voluntary arrangement has been breached, we welcome the swiftness with which Marine Scotland has responded.

"This breach highlights the importance of having statutory measures in place to protect sites from fishing pressure where appropriate.

"We look forward to a ­strategic approach to protecting appropriate areas of all existing and new MPAs in Scotland's seas."

The voluntary fisheries management arrangement which was in place at the site meant that fisherman had agreed to avoid the area as it is home to delicate maerl beds, which are a nursery habitat for young scallops as well as other juvenile fish and shellfish.

The agreements were put in place in July, but Mr Duncan described them as a "stop gap" until more formal measures can be put in place following a consultation on the issue.

He said: "There are vulnerable features in these sites which should not be trawled over and it's in everybody's interests to protect them."

Legislation allowing the introduction of MCOs was introduced in 2010, but has never been implemented until now.

Scottish Environment Secretary Richard Lochhead said the introduction of the order shows the Scottish Government's commitment to protecting marine life.

He said: "We take the responsibility for the protection of these 30 sites extremely seriously."