The biological reference point estimation report that WDFW sponsored found an MSY escapement level for Cedar River sockeye to be ~82,000 spawners and total Lk. Washington sockeye to be ~102,000 spawners. The authors found a difference in productivity between even and odd year spawners with MSY escapement of 150,000 and 69,500 spawners for even and odd year broods, respectively.

They also concluded:

1) Survival of Cedar River NOR fry to maturity was negatively related to Cedar River natural fry abundance. In addition, even-year broods survived at rates substantially higher than odd-year broods at comparable fry input levels;

2) Density-dependent survival of fry in Lake Washington is associated with early arrival of large numbers of fry prior to the spring bloom of zooplankton suggesting intraspecific competition during early lake residence. Interspecific competition with other limnetic species, in particular, with large even-year broods of longfin smelt limit odd-year brood sockeye as evidenced by lower growth and survival.

Among the authors recommendations was the thought that management of the resource must consider the abundance and timing of hatchery fry recruitment. Delayed release of hatchery fry may provide much improved survival of HOR fry rather than possibly introducing a negative impact on natural fry.

So perhaps a modification of the natural spawning goals as well as some alternate hatchery strategy (later release of fry or perhaps even smolts) might be a more successful approach if the goal is to provide routine sockeye fisheries on an introduced natural population in Lake Washington.