Rannoch Moor is also designated as an SAC, and is particularly famous as being the sole British location for the Rannoch-rush, named after the moor. It also has populations of otters and freshwater pearl mussels. The River Tay rises on the moor within the NSA, and is designated as a separate SAC for its entire length. The Ben Nevis massif is also an SAC, as are the woodlands at North Ballachulish in the westernmost part of the NSA. The final SAC within the NSA protects the woods on the western side of Loch Etive, in the southwestern extremity of the area.