The Trout is the name for a number of species of freshwater fish belonging to the genera Oncorhynchus, Salmo and Salvelinus, all of the subfamily Salmoninae.
Oncorhynchus – Pacific salmon and trout
Salmo – Atlantic salmon and various trout
Salvelinus – char and trout
Many trout habitat in just a short stretch of stream. Trout need some basic things to survive. Trout can only live in healthy waterways where there is plenty of trout food. Most important things: cold water, clean water, food to eat, places to hide from predators, and clean gravel to lay their eggs in. For most trout, even very large ones, most of their diet is made up of macroinvertebrates, or animals without backbones.
Most trout species live in freshwater lakes or rivers exclusively, while there are others which may either live out their lives in fresh water, or spend two or three years at sea before returning to fresh water to spawn.