A rare flame shell clam reef devastated by a scallop dredger could take decades to recover.

The seabed at the Loch Carron reef near Plockton in the Highlands has been badly damaged, according to conservationists.

The Scottish Government described the damage as "worrying" and said an investigation would be carried out.

Flame shell molluscs build nests from shells, stones and other materials, and live completely hidden inside them on the seabed.

Hundreds of nests can combine to make a dense bed, which supports a myriad of other species including young fish and scallops.

Conservation charity the National Trust for Scotland (NTS) has expressed shock at the damage.

Senior conservation adviser Dr Richard Luxmoore said: "They protect their nests under a fragile roof of bits of shell and other material held together with fine byssus threads.

"Ripping through this with the heavy metal teeth of a scallop dredge is like dropping a bunker-busting bomb on a nursery school. The destruction is just appalling.

"Two years ago, the Scottish Government commissioned an economic study of the impacts of fishing in the inshore zone which concluded that the use of trawls and dredges in these waters caused damage that was totally disproportionate to the profits that it brought to a relatively small number of fishermen."

He added: "The clear outcome of this research was that Scotland would be economically far better off if all such damaging fishing methods were banned within 3km of the shore.

"It is time that the Government took heed of this advice and acts to protect the marine life that is one of Scotland's natural treasures."

The reef at Loch Carron is not a protected area and can be dredged legally.

A Scottish Government spokesman said: "These reports are worrying and will be investigated.

"It is worth noting that there are already strong measures in place to protect valuable marine habitats around our coastline.

"We work closely with local communities and the inshore fisheries groups to review what, if any, additional protective measures are required."

The Scottish Fishermen's Federation has been approached for comment.