The brown trout, Salmo trutta, is native to Europe and western Asia. During the past 100 years, the species has been established in many of the cool and cold water areas of Utah, where it is now one of the most popular sport fish in the state.
Brown trout are more piscivorous (fish-eating) than many other trout species. In addition to fishes, brown trout also consume amphibians, rodents, and invertebrates, including insects, snails, and crayfish. Because of their piscivorous nature, brown trout can often have a detrimental effect on populations of both native fishes and nonnative sport fishes.
In the fall, female brown trout dig areas (called redds) in the gravel substrate of stream riffles. Male and female fish then pass over a redd, laying and fertilizing eggs. The eggs, which hatch in one to two months, are then covered with gravel. No further care is given to the eggs or young.