CONSERVATIONISTS have hailed the discovery of a previously-unknown reef of endangered sea creatures in the Clyde as “extraordinary”. 

The extensive bed of flame shell mussels, which covers an area the size of 30 tennis courts off the coast of the isle of Arran, is only the second to be found in the Clyde marine region and hints at the area’s recovery from decades of trawling.  

It was spotted by divers working with the Community of Arran Seabed Trust (COAST) – a marine conservation charity which campaigned to have the Firth of Clyde around the island designated a Marine protection Area (MPA).  

Flame shell mussels take their name from distinctive neon orange tentacles protruding from their shells, and form large mats on the seabed which provide habitats for other species.  


Flame shell mussels take their name from their orange tentacles Pic: Paul Kay

These ‘living reefs’ knit the seabed together to build a nest which supports a large variety of other marine life, enhanceing biodiversity in the area.  

Research on the only other known flame shell reef in the Clyde, at Loch Fyne, recorded 265 different animal species within samples of the flame shell bed. 

READ MORE: Scottish mussel beds linked 'from Orkney to the West Coast'

Professor Jason Hall-Spencer, of Plymouth University, described the discovery of the new flame shell bed off Arran as "absolutely amazing and very welcome news".  

Prof Hall-Spencer spent years researching the biodiversity associations of a Flame shell bed while based at the Millport Marine Biological research station 20 years ago.  

He said: "This discovery re-ignites the possibility that, with adequate protection, the once widespread Clyde Flame shell beds could one day fully recover along with wider marine and fisheries improvements.  

“I cannot commend the community on Arran highly enough for the dogged determination to recover the seas around their island and the wider Firth of Clyde." 

“It is very encouraging to hear of the discovery of an extensive and previously unknown area of flame shell reef in the Clyde” added Heriot-Watt University’s Dr Dan Harries, whose research focuses on marine benthic communities.  

“These reefs support diverse and abundant communities of marine organisms so it is not just about the discovery of the flame shells themselves – it is a discovery of an entire marine community of exceptional biodiversity.” 


The mussel beds support a wide variety of sealife pic: Paul Kay

A century ago, the Clyde had at least seven large Flame shell reefs, covering many dozens of square kilometres - Sanda-Southend, Skelmorie Bank, Stravanan Bay, Tan Buoy, Great Cumbrae, Inchmarnock, Otter Ferry and Lamlash Bay.  

Five decades of scallop dredging reduced these biodiversity hotspots to just one known remnant reef at Otter ferry in Loch Fyne, and it has only survived due to high power sub-sea electric cables rendering the ground too dangerous to fish.

Significant parts of the world’s largest flame shell bed – found in Loch Carron on the North West coast of Scotland – were destroyed by legal bottom-towed fishing activity in 2017. The area is now an within an MPA. 

READ MORE: Demands for tighter controls to protect Scotland’s precious coastal waters​

COAST have called on the Scottish Government to do more to protect Scotland’s seabeds by through better management of MPAs and spatial limits on damaging bottom-towed fishing. 

The charity also wants to see greater support for similar volunteer-run projects and activists at the community level.  


The mussel beds form a delicate ecosystem Pic: Lucy Kay

Project Officer, Lucy Kay, who was one of the divers who found the reef whilst on a recreational dive said: “Important discoveries like this are helping improve our collective knowledge of Scotland’s seas.  

“This discovery highlights the invaluable contribution of community groups and citizen scientists in helping survey and monitor the marine environment around our shores, much of which is currently done on a voluntary basis without any financial assistance from Marine Scotland.”