Puget Sound Salmon - Life Cycle

Life Cycle

The life cycle of salmon requires specific conditions within the chain of connected environments. Salmon typically live 3–6 years, which often changes depending on life conditions. While some salmon stay within the Puget Sound, others will migrate and live deeper in the Pacific Ocean. The salmon begin their journey as fertilized eggs in a stream that eventually hatch and move downstream in freshwater (lasting anywhere from months to three years depending on species). Once they mature to juvenile salmon also known as, “fry” they migrate from the freshwater stream towards an Estuary where “saltwater meets freshwater”. Here, they begin to adapt to the salt water during a process known as smoltification, which can last up to a few months. At this point, they are ready to transition through the coastal shores into the North Pacific Ocean where they stay anywhere from six months up to five years and travel as far as the Gulf of Alaska. Depending on the species, the salmon are ready to return to their home stream, river, or lake after one to seven years of being in the ocean to begin the process of spawning. Once the salmons spawn, the process beings again with the new salmon.

Juvenile salmon: The Most Crucial Stage of the Life Cycle

As mentioned above, juvenile salmon utilize estuaries to transition from freshwater to saltwater environments. These estuaries contain the necessary amount of both fresh and salt water so the salmon can steadily adapt without causing harm to their body chemistry, in the process called "smoltification". Yet while this meeting of fresh and salt is necessary, juvenile salmon use estuaries for more than a place of adaption. Eelgrass and further vegetation tend to grow in or around these shoreline areas, offering protection for juvenile salmon from predators such as larger, grown salmon. Furthermore, "juvenile salmon experience the highest growth rates of their lives while in estuaries and nearshore waters". Since nutrients are so crucial to their growth, the complex food web produced from these water plants such as eelgrass serves the juvenile salmon well, and these salmon tend to be more selective, using instincts to tell them what will better prepare their bodies for ocean residence or migration later in their lives.