Led by Dr Joanne Porter of Heriot-Watt University, 12 divers from Seasearch, the volunteer dive project co-ordinated by the Marine Conservation Society (MCS) were diving in Orkney from the MV Halton, skippered by Bob Anderson.
Seasearch is a volunteer underwater survey project for recreational divers, enabling them to contribute to protecting marine wildlife through recording underwater habitats and the plants and animals they support. Seasearch provides training for volunteer divers and organises dives and survey expeditions.
Seasearch Surveyor and underwater photographer George Brown, from Inverness, recognised a shell and pebble structure on the seabed as that made by flame shells (Limaria hians). "Only close examination of the structure revealed it was indeed inhabited. These beautiful flame shells were found in Scapa Flow at a depth of 16 metres. Interestingly, there are two other records of Limaria in Orkney, both dating back to the 1950's. So these could be the first finds for over half a century," said George.
Despite its flamboyant bright orange tentacles the Flame shell is very difficult to spot within its nest.
Calum Duncan, MCS Scotland Programme Manager and Seasearch Coordinator in Scotland said divers have once again provided keen eyes underwater. "This is certainly one of Scotland's underwater biological treasures. It's always exciting when a new record of a rare, threatened or declining species such as flame shell is made, and just goes to show how much we have to value and protect that is out of sight beneath Scotland's waves. Dr Porter, Bob, George and the other local divers are to be commended for providing an excellent example of Seasearch in action, becoming local experts and increasing our knowledge of sea life."
This is the latest record of a Priority Marine Feature, species or habitats worthy of marine conservation action in Scotland - in Scapa Flow, following finds of fan mussel, sea grass beds, maerl beds and horsemussel beds.
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