Deep sea habitats close to shore. The dramatic glaciated scenery of the west coast of Scotland continues underwater in the sea lochs, forming a special home for marine life. Deep basins, scoured out by glaciers during the last ice ages, are protected from the waves of the open sea by tidal narrows and shallow sills.

Scotland is world-famous for its extensive network of sea lochs, which are essentially fjords—long, narrow glacial valleys that have been flooded by the sea. There are over 100 significant sea lochs primarily located along the rugged western coastline and the northern islands. The most famous and longest of these is Loch Fyne, which stretches 65 km into the Argyll hills and is renowned for its seafood. Other notable examples include Loch Linnhe, which provides the dramatic sea-approach to Fort William, and Loch Long, which sits on the doorstep of the Loch Lomond & The Trossachs National Park. These lochs are critical to Scotland's geography and economy, serving as sheltered harbors, centers for salmon farming, and spectacular tourist destinations for kayaking and sailing. Unlike freshwater lochs, sea lochs are tidal and host a unique marine ecosystem of kelp forests and cold-water corals, often characterized by the presence of seals, otters, and occasionally dolphins or porpoises visible from the shore.