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Sea and Coast Proximity to the sea has a huge influence on the biological richness of Wester Ross. The area has a long, varied and very beautiful coastline, ranging from exposed headlands to deeply indented, extremely sheltered sea lochs. The Wester Ross sea lochs are true fjords, with ice-scoured basins separated from each other and from the open sea by relatively narrow and shallow sills, and in Scotland are features found only on the west coast. The coast supports a wide variety of habitats including coastal heaths and cliffs, rocky shores, sandy beaches, sand dunes and salt marshes. Our cliffs and islands are home to large numbers of seabirds, which feed at sea and come ashore to nest and rear their young, while harbour (common) seals produce their pups on offshore rocks and skerries. Turnstone and Ringed plover frequent the mouth of the Sand river in winter. Tracks of otter can often be seen in the sands nearby. Underwater, the special habitats greatly enhance the marine biodiversity of the area. Inside the quiet, sheltered basins, conditions on the seabed are similar to those in the very deep sea off the continental shelf, especially when a layer of peaty fresh or brackish water floats on the surface after rain, cutting out light and insulating the water below from marked temperature changes. Here, mud and rock at relatively shallow depths support animals which are more typical of very deep water. By contrast, strong water currents in the tidal narrows and rapids nourish a wide range of animals, and communities here include horse mussel reefs, flame shell reefs, brittlestar beds and maerl (calcareous seaweed) beds. Rich mixed sediments with many burrowing animals occur in many parts of the lochs, and seagrass beds grow in some shallow, sheltered bays. Our sea lochs are also important nursery grounds for cod and other commercially important fish species, and the outer lochs and open waters are frequented by whales, dolphins, porpoises and seals. Wester Ross is in a fortunate geographical position where both southern and northern marine species occur, and the overlap of these on our coasts adds considerably to the biodiversity compared with the equivalent latitude on the east coast. The open coasts of Wester Ross are partly sheltered by Raasay and Skye in the south, and by the island chain of the Western Isles across the Minch. The seashores are predominantly rocky, covered with barnacles and seaweeds. An offshore rock in Outer Loch Torridon is the northern recorded limit for a spongy green seaweed, Codium adhaerens. A few clean sandy beaches break the rocky coastline, with good examples at Achnahaird, Red Point and Gairloch. Sealoch shores are mainly very sheltered and covered with dense brown seaweeds. Crofter’s wig (Ascophyllum nodosum ecad mackaii) is a very distinctive form of the common egg or knotted wrack, which lives unattached on the shore in very sheltered corners where there is some regular freshwater influence. This seaweed is found in west coast sea lochs and nowhere else in the world, and has its own action plan. Another brown seaweed, moss wrack (Fucus muscoides) grows only a centimetre or two high in saltmarsh turf. Underwater, there is often a mixed seabed in shallow water, with rock outcrops in clean sediments of coarse sand and shell gravel. Boulders and bedrock are covered with several kinds of kelp, and the rocks are often scoured by nearby sand. In deeper water the sediments change from coarse grained sands to fine muds, which are inhabited by a variety of burrowing animals, while deep water featherstars are common on rocks. In the Inner Sound between Raasay and Applecross are some of the deepest inshore waters in Britain, at over 200m. In the deep mud basins, commercially important Nephrops (prawn) populations live in mud burrows amongst giant sea pens a metre tall, together with Fries’s goby, burrowing brittlestars, burrowing crustaceans and anemones. Loch Diabaig is the only place in Britain where the big deepwater brittlestar Asteronyx loveni, which lives clinging onto giant seapens, has been seen by divers in relatively shallow water at 32m. Deep, sheltered rock is another rare habitat found only in the sealoch basins, again with a very distinctive community on underwater cliffs of white sealoch anemones, ancient shelled brachiopods, seasquirts, peacock fan worms, brittlestars, deepwater featherstars and strange sponges. This community is found on the south side of Loch Carron. A greater variety of animals inhabit shallower mixed sediments. Here lives a curious ‘giant’ foraminiferan made of a single cell up to 5cm across, only recently described from a few Scottish sea lochs, including Loch Torridon and Loch Carron. The rare and nationally important fan mussel has been found at the entrance to Loch Carron in recent years. There are more familiar animals in and on these sediments too – brittlestars, starfish, hermit crabs, brown crabs, squat lobsters, flatfish and many more. Seagrass beds grow on shallow sand in a few locations, with clingfish, pipefish and stalked jellyfish being some of the more interesting inhabitants. Maerl beds are of particular importance as they are only found in 1% of UK’s inshore waters. Maerl is made up of several species of red algae, which form pink, branched nodules that lie loose on the seabed. Its white chalky skeleton is the main constituent of the ‘coral’ strands in some places on the west coast. Maerl bed with sunstars, brittlestars & soft coral. Maerl grows in relatively exposed places near sealoch entrances, as on the south side of Loch Torridon and in Loch Carron, as well as in tidal narrows. Many small marine animals find shelter amongst its branches, including the larvae and young stages of commercially important fish and shellfish. A rich community of bivalves, burrowing urchins, sea cucumbers and worms inhabit the maerl gravel which accumulates beneath the living layers. Maerl is fragile, and the beds are vulnerable to mechanical damage and smothering. Tidal rapids and narrows are particularly rich hotspots of marine biodiversity, and often contain a mosaic of different communities in a small area. Particularly important habitats include horse mussel reefs and flame shell reefs. Horse mussels use strong byssus threads to bind together seabed materials such as stones and shells. Flame shells use their byssus threads to build nests with an opening at each end, making a labyrinth of chambers over the seabed. Both molluscs stabilise the mobile sediment seabed so that a wide variety of other animals can live on or in it, greatly increasing the biodiversity. Over time, ‘biogenic’ (built by living creatures) reefs become built up above the surrounding seabed by the accumulation of dead shells and seabed materials. Horse mussel and flame shell reefs occur in Strome narrows, Loch Carron, and horse mussel beds are also present in Loch Broom and Little Loch Broom. Other important communities in tidal narrows include dense beds of brittlestars, maerl, and abundant soft corals on rock. Commercial fishing is important in the sea lochs and open waters of Wester Ross. The waters of the Minch and the west coast of Scotland have always been rich fishing grounds. Nowadays common skate, cod, hake, herring, mackerel, plaice, saithe, sole, monkfish and ling are still caught in inshore waters, but not in any great numbers. The majority of the commercial fishing relies on prawns Nephrops norvegicus with squat lobsters, crabs, lobsters and scallops also being caught. Dolphins, whales and even turtles have been recorded in the waters off Wester Ross. The most frequent visitors are the harbour porpoise, the minke whale, Risso’s dolphin and the common dolphin, which can occasionally be seen from the shore. The bottle-nosed dolphin, northern bottle-nosed whale and killer whales are also recorded. Within the sea lochs the most common cetacean is the harbour porpoise, while both grey and common seals come close to the shore to feed, rest and raise their pups. Leatherback turtles are sometimes found swimming in our waters, brought northwards on the Gulf Stream. Sea lochs are also important feeding areas for both black-throated and red- throated divers. These magnificent birds breed on the freshwater lochs of the area. Gairloch is one of several lochs of special importance with groups of 10- 20+ black-throated divers present during much of the year. alt marshes are not as well represented in Wester Ross as they are in many other parts of the Highlands. They tend to be small patches at the heads of lochs, with those at Loch Broom, Little Loch Broom, Achnahaird, and Loch Carron being the largest. They are, however, a beautiful sight in late spring when thousands of thrift flowers turn the saltmarsh turf pink, and are also very important for flowers such as the annual eyebright Euphrasia heslopharrisonii which, although very rare, has been recorded in South West Ross. Saline lagoons in the UK are essentially bodies, natural or artificial, of saline water partially separated from the adjacent sea. They retain a proportion of their sea water at low tide and may develop as brackish, full saline or hyper- saline water bodies. Only two small brackish lagoons were reported by Marine Nature Conservation Review (MNCR) surveys on this coast, at Reiff and Loch an Eisg Brachaidh, both with typical impoverished fauna and flora. Beds of tasselweed Ruppia species were reported in Loch an Eisg Brachaidh in the 1950s, but none was seen on recent surveys. Ob Mheallaidh in Loch Torridon is a fully saline lagoon with rich molluscan fauna and small amounts of seagrass. Dune and Machair Beaches are an important part of the Wester Ross landscape and they also add to the diversity of habitats.