Salmo_g
WFF Supporter
Phil,
The problem with hatchery fish depends on what you're seeking a solution for. When we were trying to increase salmon and steelhead abundance and didn't care to distinguish between hatchery and wild fish, and hatchery smolt to adult survival rates were 5 to 10 times higher than they are today, hatchery salmon and steelhead were a terrific solution. Nowadays that we value wild fish and are trying to increase the abundance of wild salmon and steelhead, a.) because it's a good idea ecologically, and b.) because the ESA is forcing us to; hatchery fish become a problem when, as mixed stocks, they encourage over-harvest through fishing, and when they spawn in the natural environment with wild fish and dilute the effectiveness of natural spawning.
This latter problem occurs mostly with hatchery Chinook (large body size fish that don't want to enter tiny hatchery outlet creeks) straying and spawning with wild salmon. Coho, being small creek spawners primarily, don't intermingle as much with hatchery strays except when hatchery coho are stocked in those dispersed creeks, which hatcheries have done a great deal of over the past 60 years or more. Hatchery steelhead are a problem when they spawn in the same places at the same time as wild steelhead. The interesting thing is that the vast preponderance of hatchery winter steelhead do not spawn at the same time or in the same place as wild steelhead. And that is why, despite 70 years of massive hatchery steelhead stocking, many, if not most, wild winter steelhead populations exhibit very low genetic introgression from hatchery fish. Different story with hatchery summer steelhead. They spawn closer to the same times as wild steelhead, and more of them seem to stray and intermingle with their wild counterparts. However, it's a case-specific issue and not a universal one. This is why I get bothered when someone uses the broad brush method and paints the issue as though the conclusion is the same in every case when it clearly is not.
Sg
The problem with hatchery fish depends on what you're seeking a solution for. When we were trying to increase salmon and steelhead abundance and didn't care to distinguish between hatchery and wild fish, and hatchery smolt to adult survival rates were 5 to 10 times higher than they are today, hatchery salmon and steelhead were a terrific solution. Nowadays that we value wild fish and are trying to increase the abundance of wild salmon and steelhead, a.) because it's a good idea ecologically, and b.) because the ESA is forcing us to; hatchery fish become a problem when, as mixed stocks, they encourage over-harvest through fishing, and when they spawn in the natural environment with wild fish and dilute the effectiveness of natural spawning.
This latter problem occurs mostly with hatchery Chinook (large body size fish that don't want to enter tiny hatchery outlet creeks) straying and spawning with wild salmon. Coho, being small creek spawners primarily, don't intermingle as much with hatchery strays except when hatchery coho are stocked in those dispersed creeks, which hatcheries have done a great deal of over the past 60 years or more. Hatchery steelhead are a problem when they spawn in the same places at the same time as wild steelhead. The interesting thing is that the vast preponderance of hatchery winter steelhead do not spawn at the same time or in the same place as wild steelhead. And that is why, despite 70 years of massive hatchery steelhead stocking, many, if not most, wild winter steelhead populations exhibit very low genetic introgression from hatchery fish. Different story with hatchery summer steelhead. They spawn closer to the same times as wild steelhead, and more of them seem to stray and intermingle with their wild counterparts. However, it's a case-specific issue and not a universal one. This is why I get bothered when someone uses the broad brush method and paints the issue as though the conclusion is the same in every case when it clearly is not.
Sg