This graph shows the same data as the previous one with the Non-local, highly domesticated (often intentionally) hatchery broodstocks removed, and provides a clearer picture of the data for supplementation programs using local broodstocks, which is the current trend.

Ford et al found no difference in lifetime reproductive success of hatchery and natural origin coho salmon after about 13 generations of hatchery operation in Minter Creek. However, the naturally spawning population was clearly dominated by returning hatchery produced fish, so the comparison made in this study may reflect as little as one generation hatchery effects.

McGinnity et al. 2004 compared egg to adult survival of native hatchery and wild Atlantic salmon, but in this case the hatchery population had been completely closed and completely isolated from the natural population for about 6 -7 generation. So, an entirely segregated hatchery program. They found no difference in egg-to-adult fitness.