As Oncy says, dealings released out of Minter returned fewer fish than fingerlings released at the Muckleshoot hatchery on the White. Same stock, but one went through the Narrows. In 00s and into the teens the acoustically tagged steelhead smolts had really low survival to open ocean when the originated in the southern Sound. Further north they did better.

Again, to my knowledge, all that was done is collect that data and not look into a reason.