The presented diagram gives information about how the life cycle of a salmon occurs.
Overall, its life cycle often takes place in three main places, including at the upper river, the lower river, and the open sea. Notably, a salmon has a lifespan of approximately 10 years.
To begin with, salmon eggs are laid at the upper river, where currents are slow-moving to facilitate their growth. Here, adult salmon choose shallow areas where reeds are well-developed, and several small stones are on the riverbed so that these natural elements can protect their offspring. It takes approximately five to six months for the eggs to hatch, resulting in fry, which are around 3 to 8 centimeters long.
In the second major phase, fry swim to the lower river, where they often spend around four years. The currents here are faster than in the upper river. After the second phase, fry gradually transform into smolts, which are often around 12 to 15 centimeters long.
These smolts migrate to the open sea, where they spend most of their lifespans, about five years, before returning to their home river to lay eggs. A mature salmon can be 70 to 76 centimeters long when it reaches its spawning beds.