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A new survey reveals the extent of seabed marine life around protected areas but threats remain, writes Nigel Williams. A new survey reveals the extent of seabed marine life around protected areas but threats remain, writes Nigel Williams. The value of creating marine reserves to protect ecosystems from over-exploitation or destruction is becoming increasingly clear, although still often resisted by fishing and other interests. So the results of a new survey of the wildlife around two protected areas of Scotland's most famous sea lochs, which have been catalogued in detail for the first time in two new reports by Scottish National Heritage (SNH), will be welcomed by conservationists. The reports document comprehensive surveys of marine wildlife hotspots on the west coast of Scotland, and reveal the full extent of an underwater treasure trove of brightly coloured reefs, coral-like beds and dense kelp forests. At one of the sites, Loch Creran, spectacular red, pink and orange serpulid worm reefs are an example of an extremely rare habitat, with only three other sites known in the world. The reefs at this site are by far the most extensive and are therefore of international importance. Formed by a pencil-sized serpulid worm, they were found to occupy a wide band around the edge of the loch, covering an area of around 108 hectares. The site, just north of Oban, also has large pillow-like sponge colonies attached to tide-swept rock walls. Dense beds of horse mussels, sometimes called Clabbies, were found to be more widely distributed than previously thought. At the other site in Loch Maddy, North Uist, divers and shore surveyors recorded 59 different habitat types, supporting over 800 species, such as the rare northern sea fan and the spectacularly colourful jewel anemone. The rocky reefs and rare coral-like maerl beds were found to be particularly species-rich. In the loch's special saline lagoons two nationally rare plant species were found, one a green algae which forms a thick green carpet. The other, the bird's nest stonewort, is known to occur in only one other place in the UK. The lagoons also support dense beds of eel grass which look just like submerged green, rolling meadows. “We have known that Loch Creran and Loch Maddy are internationally important for the vast number of animals and plants which thrive there,” said Graham Saunders, environmental audit officer for SNH. “However this is the first time we have really quantified just how rich the reefs and other habitats are, and have attempted to gain an overall picture of their condition. These lochs really are breathtaking examples of Scotland's marine environment.” “On the whole we have found the lochs to be in good condition although there is some worrying evidence of past damage by fishing gear and some areas have shown declines in the abundance of particular species.” Results using sidescan sonar, a technique that uses the penetrating properties of sound rather than light to build up a photograph-like image of the seabed, showed evidence of reef damage by fishing gear in Loch Creran. Damage included single and twin parallel tracks on the seabed stretching to around three metres wide with broken reef rubble. Horse mussel beds also showed signs of decline at two study sites in Loch Creran. Research has shown that they are producing young mussels at an alarmingly slow rate, with the majority being at least 11 years old. This has led researchers to conclude that horse mussels are particularly vulnerable to damage and need further protection within the lochs. Jane Dodd, a marine project officer for the SNH, said that the reef map was being used to work with other stakeholders to help strengthen protection of the special habitats of the loch. The sidescan sonar images have been invaluable for showing the additional damage that boat moorings are doing, she said.