The diagram illustrates the life cycle of the salmon, detailing its physical development and migration across three distinct aquatic environments.
Overall, the salmon’s life span is a cyclical process that involves significant growth and multiple relocations, commencing in freshwater rivers and culminating in the open sea before returning to its birthplace to reproduce. The entire cycle spans approximately nine years.
The process begins in the upper river, characterized by slow-moving water, where salmon eggs are deposited among reeds and small stones. After an incubation period of five to six months, these the eggs hatch into “fry,” measuring three to eight centimeters. These The fry then migrate to the fast-flowing lower river, where they remain for roughly four years and develop into “smolts,” growing to twelve to fifteen centimeters.
Following this stage, the smolts transition to the open sea. They spend approximately five years maturing into adult salmon, which reach a substantial length of seventy to seventy-six centimeters. Finally, these the adult salmon swim back to the upper river to lay eggs, thereby restarting the biological cycle.