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
Salmon usually associated with the demise of salmon runs. Salmon recruitment can be affected by beavers' dams because dams can: Beavers' dams are able to nurture salmon juveniles in estuarine tidal marshes where the salinity is less than 10 ppm. Beavers build small dams of generally less than high in channels in the myrtle zone. These dams can be overtopped at high tide and hold water at low tide. This provides refuges for juvenile salmon so they do not have to swim into large channels where they are subject to predation. It has been discovered that rivers which have seen a