The diagram illustrates the life cycle of a species of large fish known as the salmon, highlighting the different stages of development and the habitats in which they lives.
Overall, the life cycle of salmon consists of three main stages: fry, smolt, and adult. During this process, they migrate from freshwater rivers to the open sea and eventually return to their birthplace to reproduce.
In the initial stage, salmon eggs are laid in the upper river, where the water flows slowly. These eggs are typicall deposited among reeds and small stones for prtection. After approximately 5-6 months, the eggs hatch into fry, which are small fish measuring around 3 to 8 cm in length . Next, the fry move downstream to the lower river, where the water flows faster. They remain there for about four years, during which they grow into smolt, reaching a size of roughly 12 to 15 cm. In the final stage, the smolt migrate to the open sea. They spend around five years in this environment, growing into adult salmon that measure between 70 and 76 cm. Eventually,the mature fish return to the upper river to lay eggs, thereby completing the cycle.