Matt,

Thanks for taking the time to share your thoughts. There’s definitely some upside to this and I’m definitely emphasizing the negative and looking past the potential upside to a large degree. I certainly wouldn’t disagree with anything that you stated. However, I’m not sure it’s entirely fair to state that the loss of all but~5% of the once existing floodplain habitat has been overlooked. I don’t know for certain, but I’m inclined to think that nothing has been done to address that issue in the past simply because from a geomorphological standpoint, it would be impossible to restore or rebuild the lost floodplain habitat anywhere remotely close to where it historically existed. With our rock armored levies, and the subsidence issues in the delta, areas that used to flood every year, have simply lost that ability and I’m not seeing how it could somehow be restored without some very major restructuring and lots of political hurdles.

I’m all for the restoration of existing habitat. And I’d certainly admit that I have a bias in favor of such restoration over other methods of potentially increasing abundance. I’d definitely agree that gravel replenishment to offset the natural loss of sediment transport caused by dams in the SR-SJ basin hasn’t “worked” but I think that has a lot more to do with the fact that there’s a minimal amount of suitable habitat that can be effectively restored via gravel replenishment on the severely truncated Sac river tribs.

I’d feel a lot better about this arena of study if the simulated flood plain habitat were closer to the mainstem and the more commonly used migration path and could be discovered and exploited by the out-migrants by default. The problem as I see it is that for the fish to find and exploit any simulated floodplain habitat created in the bypasses is going to require a fairly large detour from the mainstem, meaning it will only be exploited by a percentage of fish on top of the seasonality issues you mention. Thus the potential upside would be highly variable as I’m seeing it under the best case scenario. And I’m seeing the potential “what if?” questions leading to paths I don’t think we want to venture down:

What if we maximized the fish utilizing the artificial floodplain habitat, by mechanically inserting, growing, and then relocating the fish?

What if we reduced the seasonal variability aspect by not flooding the entire flowing bypass but by flooding static individual rice fields? Because to do that, you only need a few acre feet and even that would only be required on dry years.

What I’m seeing is potentially millions more, rice grown, hatchery frankenfish as the only thing that comes remotely close to being a “given” here.

I think you’re definitely correct that there’s a potential upside here, and I’ll certainly admit I was looking past that upside and I really wish I could share your level of optimism. Truth is, this really scares the hell out of me.

That said, I sincerely hope that your optimism proves to be well founded and my opinion that rice fields will become extensions of hatchery raceways proves to be wrong.