The diagrams illustrate the intricate life cycle of the salmon, detailing the various stages from spawning to maturity.
Overall, the life cycle encompasses several phases, including the initial spawning in freshwater, growth in both river and sea environments, and eventual return to the original spawning location.
The life cycle commences with the salmon spawning in an upper river characterized by slow-moving waters, abundant reeds, and small stones, where eggs incubate for a duration of 5 to 6 months. Once hatched, the salmon emerge as ‘fry’ measuring between 3 to 6 centimeters and begin their journey downstream to a lower river section featuring fast-flowing waters. During this stage, the ‘fry’ remain in the river for approximately 4 years, during which they undergo growth and development, culminating in the next significant life stage known as ‘smolt’, reaching lengths of 12 to 15 centimeters.
Subsequently, the smolt migrate into the open sea, where they continue to grow and develop into adult salmon. In this marine environment, the salmon attain lengths ranging from 70 to 76 centimeters. This adult stage is sustained for an estimated duration of 5 years before the salmon return to their original spawning grounds to initiate the cycle anew, completing their remarkable life journey.