Chinook salmon successful at guarding their redds. Chinook eggs hatch, 90 to 150 days after deposition, depending upon water temperature. Egg deposits are timed to ensure the young salmon fry emerge during an appropriate season for survival and growth. Fry and parr (young fish) usually stay in fresh water 12 to 18 months before traveling downstream to estuaries, where they remain as smolts for several months. Some Chinooks return to the fresh water one or two years earlier than their counterparts, and are referred to as "jack" salmon. "Jack" salmon are typically less than long, but are sexually mature and return at
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