Sea trout is the common name usually applied to anadromous (sea-run) forms of brown trout (Salmo trutta), and is often referred to as Salmo trutta morpha trutta. Other names for anadromous brown trout are sewin (Wales), peel or peal (Southwest England), mort (Northwest England), finnock (Scotland), white trout (Ireland) and salmon trout (culinary). The term "sea trout" is also used to describe other anadromous salmonids, such as coho salmon (Oncorhynchus kisutch), coastal cutthroat trout (Oncorhynchus clarkii clarkii), brook trout (Salvelinus fontinalis), Arctic char (Salvelinus alpinus alpinus) and Dolly Varden (Salvenlinus malma). Even some non-salmonid fish species are also commonly known as sea trout, such as Northern pikeminnow (Ptychocheilus oregonensis) and members of the weakfish family (Cynoscion). Range Anadromous brown trout are widely distributed in Europe along the Atlantic and Baltic coasts, the United Kingdom and the coasts of Iceland. They do not occur in the Mediterranean Sea but are found in the Black and Caspian Seas and as far north as the Barents and Kara Seas in the Arctic Ocean. Brown trout introduced into freshwater habitats in Tasmania, Victoria, New Zealand, Falkland Islands, Kerguelen Islands, Chile and Argentina have established anadromous populations when there was suitable access to saltwater. Anadromous behavior has been reported in the Columbia river and its tributaries in the U.S. and in Canadian rivers on both the Pacific and Atlantic coasts. Taxonomy As treated here, the anadromous sea trout Salmo trutta morpha trutta is not taxonomically distinct from the freshwater-resident forms of the brown trout, i.e. the lacustrine S. t. morpha lacustris and the riverine S. t. morpha fario, although previously they have been considered different subspecies or even species. They represent ecological forms with different migration behaviour. Originally the name Salmo trutta was used to refer specifically to the anadromous or sea-run forms of brown trout. Early angling literature often referred to sea trout as white trout or bull trout. Description Anadromous brown trout are a silvery color with faint black spots. However, once they return to freshwater they quickly take on the normal coloration of resident brown trout in preparation for spawning. Sea trout kelts (post spawn) return to their silvery stage as they migrate back to saltwater. Adult brown trout are between long, and can weigh from . Breeding males will develop a hook-like, upward-facing protrusion on the lower jaw called a kype. In freshwater the top of the trout is an olive