Spear Fishers on the American river

[Darian]

"....and state that I don't believe that one can support the presence of stripers and concurrently support native/wild salmon and steelhead. These fish are being eaten long before they reach the Delta pumps and virtually every diversion on the Sac is screened, so it isn't either of those scapegoats. They are being eaten by other fish, and of the two primary culprits, one of them is invasive." (Italics added)

Interesting belief. I, for one, believe that all of these fish native or naturalized are deserving of our collective support. They've settled into a niche suited to their requirements in the environment for lengthy periods, now. I wouldn't sacrifice any of the Salmonids or Stripers for any of the other. That may be a selfish point of view in KJE's view, but it is what it is.

KJE cites two "....primary culprits...." for predation on anadromous Salmon/Steelhead smolts and says that one of these predators is invasive. Actually, there're more than two invasive predators in the Sacramento/San Joaquin Delta/SF Bay systems and the ocean; all of which are environments that anadromous Salmon/Steelhead use for parts of their life cycles. How about Herons, Pelicans, Cormorants, Osprey, Black Bass, Otters, Halibut, Sharks, Grouper, not excluding adult Salmon/Steelhead to name a few??? Big fish eat little fish and other predators eat them too. I've read some responses to proposed attempts manage/reduce Striper predation that suggest that removal of Stripers most likely result in expansion of the population of other predators. Seems to me that the chart used to support KJE's claim appears correct as far as it goes (fresh/brackish water) but isn't sufficient to support the implied claim that Stripers are the primary culprit.

Even if we accept that all diversions are fully screened and cause zero mortality (and I don't), ag water run-off is untreated and full of mineral salts, fertilizer, herbicide, insecticide chemicals freely released into our waterways (not to mention pollution from partially treated municipal sewage treatment facilities). I'm not sure whether anyone has actually conducted an in depth study of the impact of the degraded ocean environment (oxygen depletion events, changing PH balance, changes in major currents, etc. etc.), yet. But it certainly would add to the body of knowledge on how to best manage for survival of all anadromous species.

These days I'm even wondering if Stripers should be considered invasive, given that their geographic range has shrunk over time after stocking from Oregon to mid-CA on the Pacific Coast?? While it's true that vestiges of those populations still remain in places in Oregon and the CA north coast, there doesn't seem to be enough of them to excite interest beyond dreaming about what was in the past. Of course, this last part is mere speculation on my part but food for thought.

[Rossflyguy]

The other predators you mentioned aren't invasive but native. Not sure what the point is? Half of which are salt water species that prey on the salmon/steelhead who survived their first life cycle.. They don't compare to the Striper who inhabits both salt and fresh water systems.

[Darian]

Actually, I'm not sure why you couldn't understand the point(??). My point was there're more than two principal predators in the area included in the chart, more than one is invasive and that doesn't take into account the ocean environment. To name just a few, Black Bass are non-native and invasive, Cormorant are significant predators, inhabit the entire west coast, and live in the Delta and the ocean. I could add to this list, Pinnipeds (Seals/Sea Lions, etc.) as significant predators. They live in the ocean and the Delta too. Just seemed to be getting into overkill. So, with that in mind, I'm not sure what your point is??? Ya know, nevermind.... It's not worth pursuing any further.

[Rossflyguy]

All of the predators you mentioned are native species other than the Florida strain bass. That's my point. Those cormorants aren't going to snatch steelhead and salmon as much as a Striper would. Don't know why everyone tries to argue the fact that stripers take a big dent out of the smolts. There's no argument.

[Darian]

Actually, I didn't say that Stripers aren't a primary predator on anadromous Salmonids. Just trying to point out that there's a lot more to this than laying the blame for demise of Salmon/Steelhead stocks at the feet of Striped Bass. Not sure about this but I'm not sure there's been a lot of studies done on the impact of predators other than Striped Bass (native or non-native) on Salmon or Steelhead in the Delta or rivers of this state. And, regardless of whether a predator is native or non-native, the impact on prey fish is the same. So, that's a non-issue as far as I'm concerned.