The diagrams illustrate the life cycle of a large species known as salmon. It is clear that there are four stages in the salmon fish life cycle, starting from eggs to adulthood. The process occurs in three types of environments: upper river, lower river, and open sea.
To begin with, adult salmon fish lay their eggs in the upper river, where the current is slow. They spend approximately 5 to 6 months in the stony riverbed, enjoying protection from reeds until they are ready to hatch. Once hatching takes place, the baby salmon, known as ‘fry’ (which measure around 3-8 cm in length), move downriver where the current is faster, and they spend about 4 years of their life there.
After this period, they grow larger, reaching sizes of 12 to 15 centimeters, and are referred to as smolt. The smolt then migrate to the open sea, where they will spend about 5 years. After spending approximately 10 years of their life, they become adult fish, which measure 70 to 76 centimeters in length. Eventually, an adult salmon returns to the original spawning site, where the egg-laying process will begin once more.