Salmon eggs hatch in freshwater streams and, during their first year of life, the young salmon migrate distances up to 1,000 km
in order to reach the ocean. Here they spend up to 5 years where they feed and grow, acquiring more than 95% of their biomass. During the summer of their maturing year, they begin the long journey back to their home streams to spawn. Although it is still uncertain how salmon navigate back to their spawning grounds, current hypotheses suggest that they have a highly developed sense of smell that allows them to remember odors they encountered on their migration to the ocean. They then use these odors to help them navigate back to the streams where they were born. At the spawning grounds, females use their tails to form a hollow cavity in the stream gravel where they lay up to 8,000 eggs. The males fertilize the eggs, and both adults typically die soon thereafter. The physiological response that allows salmon to survive in fresh water, then in salt water, and then fresh water again is an example of ________.
Acclimation is the physiological response or phenomenon which is responsible for survival of salmon in fresh water and salt water.
When a young salmon starts its sea journey it travels wide distances in search for oceans completing a leg of their journey. They travel back to home streams for spawning. This survival in different osmotic potentials and salinity is due to osmoregulation and acclimation. System of salmon detects saline change and instigates a negative feedback system to the body water concentration. Similar feedback works contrastingly when salmon is in freshwater or marine streams of water.
Hence, the physiological response occuring in salmon is acclimation.