The diagram highlights the stages in the life cycle of the salmon. Overall, the cycle comprises seven main stages. Notably, having hatched from eggs, the fish takes four distinct shapes until it finally reaches maturity and reproduces shortly before its death.
The salmon begins life as an egg in fresh water environments. The eggs spawned by adults usually hatch within around three months, and a life form known as alevin appears. The alevin feeds exclusively on yolk sac for several weeks before it becomes 5-10 weeks old and turns into a fry. It is worth noting that the fry resembles a typical fish, has already developed fins and begun to swim. After growing further for a few more months, the fry changes into a parr, and at this stage, it has different brown coloration and special “finger” markings across its body.
The next stage in the salmon’s life is smolt, when it is 1-3 years old and starts to form schools with other fish of the same type. These groups of smolts usually start their journey towards the open sea, and having spent 1-6 more years there, it finally reaches maturity. An adult salmon has noticeably larger fins and blue shades. This is where the fish begins to reproduce, having markedly changed in appearance with a differently shaped head as well as tail and developed red coloring. Its life comes to an end after breeding for two weeks.