The drawing illustrates how salmon grow from eggs to mature individuals. Overall, the life cycle of a salmon includes 7 steps. The main stages, beginning with the development of eggs to become a parr fish, end with becoming a spawning adult.
The first stage is when eggs are laid in fresh water; after 3 months, given sufficient conditions, they become alevin, which feed off a yolk sac and have orange skin for several weeks. After this stage is complete, in about 5 to more than 10 weeks, the alevin grow into fry with more colorful skin, having yellow and green in their bodies and a little pink in their tails. Subsequently, the fish, now called fry, continue to become parr after several months, and they are about as long as an adult finger; now, they have dark skin.
Once the eggs develop into parr about the size of a finger, the smolt stage is able to start. When they are about 1 to 3 years old, they can go in groups and move out to sea. At this time, they change their living conditions from fresh water to the beach, and for about one to six years, they all live and stay in the sea. Finally, the adult fish grow bigger and bigger day by day, and now they are spawning adults. They use their final time to stay and continue to lay eggs, and then they will die within two weeks.