Euryhaline organisms:
Euryhaline organisms tolerate a wide range of environmental salinities. They maintain internal water and ion balance by adjusting osmoregulatory processes as external salt concentration changes. Estuarine fishes such as salmon during migration alter gill ion transporters, kidney function, drinking behaviour, and hormonal regulation when moving between fresh water and seawater. In fresh water, water enters osmotically and salts tend to be lost, so animals excrete dilute urine and actively absorb ions. In seawater, they risk dehydration and salt gain, so many drink water and actively secrete exc
Ref: Evolutionary Analysis, Herron & Freeman, 5th Ed., Ch. 10
