First of all let me state that I am in no way a Fisheries Biologist. I am a invasive plant biologist with an aquatic weed emphasis in recent years. I do not have any pull or control when it comes to fisheries management. I am simply stating my opinion. I love to fish and spend the majority of my life dealing with invasive organisms. I too hate having the native vs. non-native discussion; I get enough of that at work. My job is currently transitioning towards outreach and education. Here in California the general public has virtually no experience/education in regards to invasive organisms. When I tell people I work on weeds they all assume I work for the DEA or CAMP. Recently I have heard of some groups looking at attempts to control invasives as a form of prejudice or racism. Next they will tell us the Lion will lay down with the Lamb. That said if anybody ever wants help or information on invasive plants please feel free to contact me. If you would like a presentation on invasive aquatic weeds or identification of the plants you see out there I will be more than happy to help.
Getting back to the post, it is true that there are many other variables in the Delta that are leading to the demise of the fishery. Non-native fish definitely play a part. I never said they were the scapegoat or smoking gun. I also have never once suggested we should try to eradicate/remove them from the system, that would be cost prohibitive if not impossible. There are many other problems and possible solutions in the Delta. Restoration of flood plains to increasing foraging opportunities of salmon smolts. Research suggests that floodplain feeding by salmon smolts leads to significant increases in growth over smolts that feed only in river channels. When working on the San Joaquin between Mossdale and the Port of Stockton I have traveled through patches of frothy water that is so rank it made my eyes burn. Nutrient loading and decreased dissolved oxygen lead to dead zones that kill young fish as they migrate through. Franks Tract and Clifton Court act like giant sumps with one way valves that fish get sucked into and cannot get out of. While there introduced centrarchids (BASS) devour them. I have seen pictures of large stripers from the American with adult steelhead in their throats. Reversed flows to the Old and Middle River confuse migrating fish thinking they are swimming downstream towards the ocean. Invasive plants change the ecosystem, nutrient recycling, provide ambush cover, reduce turbidity, etc.
All these conditions impact native anadramous fish as they make their way to the ocean. Many of these problems could probably be improved if the historic conditions of the Delta, increased summer salinity, returned. As it is now the Delta is managed as a massive freshwater lake. This goes against the native species that evolved here and is totally in favor of non-native introductions. I hate to think that anybody would fight to support a non-native organism in the Delta that DOES impact the recovery of native fish. There are hundreds of opportunities to fish for bass and stripers in area reservoirs. Have you ever seen the Striper they pull out of San Luis and Mendocino? We do not have those same options for salmon/steelhead. The Delta and Sacramento River system are it. The San Joaquin run is already gone. The recent crash of the Sacramento system salmon runs might close down the entire west coast salmon industry.
We should look at salmon/steelhead as an indicator of the future. If we continue running the Delta into the ground we may be looking forward to no fishing opportunities. What if the salmon/steelhead runs crash? What if we then get a massive earthquake causing subsidence in the Delta that leads to levee failure, leading to a catastrophic increase in salinity? What if this wiped out the majority of the introduced centrarchids and there were no native stocks left that can tolerate those conditions? Surely some would retreat and find new niches but the overall numbers in the Delta would surely go down. I know that sounds very doomsday but that is the beauty of native organisms. They have adapted to historic conditions in the region. You lose those genes and you are really gambling. The introduced fish are doing well in a system that is highly manipulated by humans. Now all the above could occur and salmon/steelhead would probably thrive. Perhaps Sacramento Perch would be able to be reintroduced to their native range and survive in the floodplains. Striped bass may even benefit from increased pelagic food sources in the saltier western Delta. Invasive aquatic plants in the Delta (you would not believe how many of the plants you see out there are not native) would most likely be impacted by higher salinities. These plants provide centrarchids ambush sites to intercept smolts as they migrate downstream. These fish would most likely move farther upstream to fresh water while giving salmon smolts a chance to grow in the saltier Delta. If all of this happened you would still be able to go fish for striper and bass in area reservoirs.
I am done with this discussion. There will always be people who see things differently than me. People are always hesitant to give up a little for the greater good. People are against closed zones or refuges as they see those as wasted government land because they can’t go in and hunt/fish there. It has been proven time and again that refuges lead to increased hunting/fishing opportunities in the area. I am not saying one way or another that I support closing the American River. I was just bothered by the fact that someone would start a lawsuit saying the State of California should do more to support a non-native fish in the Delta when that fish HAS an impact on the recovery of native fish. We need to stop managing the Delta as a freshwater transport corridor and move towards recovery of our native fish. I believe that with some creative thinking we can attempt to solve some of these issues. Just take a look at the PPIC Report on the future of the Delta http://www.ppic.org/main/publication.asp?i=671 The bottom line is that somebody is going to lose out whether it be farmers, water users, developers, wildlife. We cannot keep managing the Delta the way we do. When change finally happens there will be resistance and lawsuits. I just hope that any resistance from the fishing community is in the name of native fish and not introduced species. I don’t know why I get so worked up on message boards. As others have said nothing is ever going to come of it. This settles no more than a couple guys bickering in a bar does, except then at least there would be a face to associate with a name. Thanks for reading.
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