The Flame Shell
Flame Shells Limaria hians (commonly called the flame shell or gaping file Shell) are beautiful little bivalve molluscs at about 4cm long. The flame shell resembles a scallop with a bright orange fringe of tentacle-like filaments emerging from between its shells. They can bind stones, algae, old shells and other bottom materials together, using their byssal threads and secretions, to form ‘nests’. If not physically disturbed these nests will meet with neighbouring nests and a carpet of flame shells is the result. These carpets can cover large areas.
Flame Shells can build up a colourful reef that supports other many other organisms. Many animals can crawl between the spaces of the shells and the fixed substratum. Flame shells help stabilise any nearby Maerl beds, by the virtue of their sticky secretions. Like wise the flame shells provide point of attachment for seaweeds out of their typical rocky shore locations. Recently it has been shown that Flame Shell beds are among the richest and most diverse habitats of UK inshore waters
The biodiversity flame shell beds provide is coupled with their importance as a refuge for juvenile fish species, for example Cod and Saithe. The beds act as settling points for Scallop Pats, so their economic significance and their significance to the wider food web is without doubt.
Flame Shell is commonly found on seabeds of mixed muddy gravel and sand often in tide-swept narrows in the entrances or sills of sea lochs. They are found from 5 to 10M down to approximately 30M deep, at bed depths of their reefs to 5cm to 20cm deep. Beds have been seen to cover several hectares as in Loch Linnhe, where strong currents help remove waste products, important for any sedentary organism, and provide a greater influx of food. Undisturbed a flame shell bed may be able to exist for over 100 years.
Flame shell beds are known to be in several lochs along the west coast of Scotland, from Loch Broom in the north to Loch Fyne in the south. Flame Shell beds seem restricted to this area and as such are of National UK importance and a priority habitat.
Loss of Flame Shell beds is due to physical disturbance. Removal of vast quantities of the seabed takes many years to recover from. A 7.5M wide area of removed bed is predicted to take over 100 years to recover. If nest material remains in tact then Flame Shells can re-colonise quickly.
A film by Andy Jackson
Sea Cucumber - Psolus Phantapus
Andy Jackson spent a week diving in Loch Duich, near the spectacular Eilean Donan castle in the western Highlands. He was searching for Psolus phantapus, an underwater creature that appears in sudden forests while breathing through its bum.
Sounds clever? It’s a pink-spotted sea cucumber. But you will gape as you watch it feed, long tentacles pulling food from the tide, stuffing it through a hole that looks astonishingly like… Well, like the bit it breathes through.
These amazing creatures colonise a muddy bank, 14m deep, near the tiny hamlet of Inverinate. Each May, they appear, and then they disappear. No one knows why.
They haven’t chosen an easy filming location. Even dancing scallops make silt clouds that hang thick in next-to-no tide. Ambient light changes rapidly. The Psolus are skittish. A passing crab will stop them feeding or make them dart under the mud.
At one end, ten arms spread out of a soft body and feed the central mouth. At the other end, their bottoms wink, disposing of waste – and breathing.
We do wonder which end they talk out of.
Although Spring sunshine has been warming our waters, in Loch Duich, it was a week of extremes beneath the snow-capped munros. Weather changed hourly: from icy hail storms with thunder and lightning to quiet stillness with beautiful light and warmth.
It was a magical week, discovering these striking animals in all their splendour. Big thanks to Janet Ullman, George Brown, and Sue Scott for their generous help and support.
The film was featured on episode 12 of BBC Springwatch, on Thursday 11th June.