Boater,

Depending what hatcheries the smolts come from affects the smolt outmigration mortality. That is, hatcheries farther from the ocean will have a higher smolt mortality rate than smolts leaving a hatchery or net pen that is located near the ocean. And particularly, hatcheries upstream of dams are going to have much higher smolt mortality losses than hatcheries downstream of the dams. So more smolts survive to reach the ocean, but of course those smolts do not contribute to the Columbia River fishery as returning adults except near the net pen release sites and the few nearby tributaries that the adult fish stray into.

Sg