The
brown trout (
Salmo trutta) is a
European species of
salmonid fish that has been widely introduced into suitable environments globally. It includes both purely freshwater populations, referred to
Salmo trutta morpha
fario and
S. trutta morpha
lacustris, and
anadromous forms known as the
sea trout,
S. trutta morpha
trutta. The latter migrates to the
oceans for much of its life and returns to fresh water only to
spawn. Sea trout in the UK and Ireland have many regional names, including sewin (Wales), finnock (Scotland), peal (West Country), mort (North West England), and white trout (Ireland).