Salmon run plankton. At this point the baby salmon are called "fry". At the end of the summer the fry develop into juvenile fish called "parr". Parr feed on small invertebrates and are camouflaged with a pattern of spots and vertical bars. They remain in this stage for up to three years. As they approach the time when they are ready to migrate out to the sea the parr lose their camouflage bars and undergo a process of physiological changes which allows them to survive the shift from freshwater to saltwater. At this point salmon are called "smolt". Smolt spend time in
Puget Sound salmon recovery 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".