Discussion in 'Fly Fishing Forum' started by eJohn, Sep 12, 2005.
Got so excited I double posted.
I can...pick me! Pick me! (I can also Sinlahekin.)
why not have everything c&r for steelhead if they are in short supply? mike w the elk slayer.
Mike, the issue really isn't numbers of steelhead. The issue is numbers of "wild" steelhead. When the National Marine Fisheries took over the river they declared the run in such bad shape that tagged both the wild and the hatchery fish as endangered. Since that time, they have back tracked and decided hatchery fish are evil and they don't want them spawning with the wild stock so they open a season to let people keep hatchery fish (But the WDFW later disclosed that they didn't clip the adipose fins of hatchery fish for several years to boost "wild" fish numbers so who knows if there are truly any wild fish left in the river.).
They base the season on the number of wild fish in the river combined with stats on C&R mortality rates times the results of creel surveys. When the numbers reach a point that they feel enough wild steelhead have been killed by C&R mortality, they close the season. So basically that is a long winded answer to say that enough wild steelhead have to go over Wells Dam to meet the quota for the river. Once that happens then they open the season to get the hatchery brats out of the river.
bonk the brats.
I have to ask this question. What is the difference between the hatchery fish and the wild fish? To me the tame fish is born and raised in a clean enviroment but only until they are about 6" or smaller, then they are released into their home stream to live like a regular fish. They all go out to sea and then come back as an adult after about two years. One would think that these fish still have the ability to spawn even if their first year was different that the wild one.
This is something that I just don't understand. Maybe I need a truck to fall on me so I can understand what is the difference.
They can and do spawn. There is some evidence that they don't spawn as successfully as wild fish. Also, since I imagine they imprint on the hatchery facility itself, I presume some go back to the hatchery before they get around to spawning. It is thought by some (and I personally am a believer, but what do I know) that over time hatchery fish will weaken the overall genetic diversity of a particular distinct population segment if there is significant interbreeding with wild fish. Which is why lots of people say bonk the hatchery fish any chance you get. (It's not always legal to, so make sure you know the regs for the water you are fishing before you do bonk one.)
Jim, believe me you're not the only one to be confused on this, but I believe the difference is supposed to be in the genetic stock of the naturally breeding fish that they are trying to preserve, vs. the hatchery fish.
The genetic stock of the “wild” fish is deemed to have a higher propensity to continue to successfully spawn in the wild under the specific conditions found in that river system.
However, given that the placement of dams entirely killed out the entire original genetic stock, the discussion of "wild" fish should not lead you to believe that they are "native" fish stock, only that they are reproducing successfully in the river and not in a hatchery, and have done so for several generations.
OM - Not exactly sure what your question is but I believe you are trying to assess why hatchery fish can be a bad thing? Am I on the right track? If so, it basically boils down to the fact that most (not all) hatcheries use a different stock/strain of fish for their hatcheries than is naturally occuring in the system into which they are introduced.
Why is this a bad thing? Well for one thing as you stated, the brats still can and do breed. When they breed with the natives they thin out the native gene pool. This can be an important factor for future generations of native fish in that their genetic code may include special adaptations (i.e., the ability to tolerate higher temps or maybe lower oxygen levels, etc.) that over generations have allowed them to survive better in their native habitats than other similar strains. By diluting these adaptations, the hatchery fish may be potentially adding traits to the gene pool that will decrease the survival rate of native fish and in the event of a natural catastrophe the natives may not be able to bounce back.
In addition, the introduced strain may bring with them a disease that they are resistant to but the natives are not. As a an example think of whirling disease. This may not be the best example because it deals with distinct species but you'll get my drift. Brown trout originated in Europe and in doing so, developed a resistance to whirling disease which is also native to Europe. Somewhere along the line, browns brought over here from Europe took a little bit of whirling disease with them. Eventually as I'm sure you know, this disease made it's way into some of the blue ribbon waters of the west and that resulted in the subsequent decline of native rainbow trout in several river systems.
There's more but I figure that should be a good start for you.
Lesson to be learned: Don't f#^k with mother nature unless you know the ramifications.
1. Competition with native fish
2. Predation of native fish
3. Reduction of genetic fitness of native fish, thereby reducing survival of future generations
I think I'm kind of confused also. You hear a lot of bad talk about hatchery fish, and for the most part it seems well founded. Everything Tom H said makes perfect sense. But then if hatcheries are bad for the river systems, why are they introduced in the first place. Is it a sort of lesser of two evils thing? If I've got it right, hatchery fish are put in to boost the population. I don't know. I guess I just find it all a bit confusing too.
You probably find it all confusing because it's a mother of a confusion!
What's been said about hatchery origin fish is correct. But the management of upper Columbia stocks is not so simple. Yes, hatchery fish have negative effects on wild populations. But the reality of the populations of fish on rivers like the Methow is that there are 9 dams and 9 associated reservoirs downstream, with all of their associated incidental mortalities. Armchair biologists out there who've taken a few fisheries or ecology classes often carry on about how hatcheries and how they're bad ALL OF THE TIME. I personally don't believe it is a black and white case in a river like the Methow. The smolt to adult survivals and recruit:spawner ratios are just too low to maintain a population during all but the very best years of minimal sport and commercial fishing and favorable ocean conditions.
Habitat and water quality have never been issues in the Methow. The fact is, the fish are dying outside of the Methow Basin and the hatchery fish are there to augment the initial number so that enough survive to return as adults. Take that supplementation away and it won't matter how fit the wild fish returning are, they won't be able to sustain the population over a few generations.
Historically, there were a few years there where no anadromous fish made it back to the Methow. So it's arguable, as someone eluded to earlier, that the fish here are no longer 'native' but rather just 'wild'. It's a good point. However, there are studies out there that show significant evolution of phenotypic and genotypic traits over short periods of time in sockeye and chinook populations. So who's to say we shouldn't attempt to allow that to continue to happen in the Methow by trying to utilize as much wild genetic material in the hatchery stocks, while minimalizing hatchery progeny in the broodstocks, thus domestication (ie bonking the hatchery brats and excluding them in hatchery operations)?
Just my thoughts
Ahh, at last, an expert chimes in. Thanks for the elucidation Jackchinook.
It seems that a delicate balance is being sought here, where today’s action may lead, in hindsight, to be inadvertently misinformed, but the option of not supplementing with some hatchery stock and having a potential disappearance of steelhead from the Methow River would be by far the greater evil.
I read the question posed by one NW editor that killing the hatchery based fish in the Methow might lead to an eventual closure of that season if it’s too successful, once the hatchery fish are fully harvested. But it seems to me, from what you're saying, that supplementation will likely be a continuing process into the foreseeable future.
Jackchinook - I'm not saying all hatcheries are bad. Just pointing out some of the drawbacks. There are other considerations as well. How about residualization of hatchery fish? In other words, those hatchery fish that survive and breed in the wild but then remain in the system as "trout". Just as you pointed out this is a very confusing issue and we don't have anywhere near the data we need to make informed decisions so I guess we just keep our fingers crossed and hope for the best.
And no I'm not an armchair biologist (UW Fisheries Management Class of '80).
Tom, for the record, I was harboring some thoughts of people outside the forum who've recently made their opinions well know here in 'the valley'. I wasn't calling you names, though having re-read my post I can see how it would seem so. No disrespect whatsoever, you seem very astute at the subject.
As far as residualized hatchery fish, we do monitor them in the Methow. Chinook residuals, or 'precocials' as we call them are few and far between, as best as we can observe. Residualized steelhead smolts, on the other hand, are a major concern in the Methow and the 'trout' fishery that exists, particularly on the Twisp, Chewuch and upper Methow rivers, consist almost entirely of these smolts. We're constantly trying to figure out how to minimalize this phenonmenon because, as you know, the fish directly compete (and outcompete) native rb's, ct's, bt's etc. Residualism is a problem anywhere you have a hatchery operation, though it has been documented in the wild too. Just another strategy that I personally feel is exacerbated by the nature of the migration corridor....small male fish can fertilize many eggs, while females have to get big in order to make sizeable contributions to the population. If males who residualize can contribute genetic material at the population level and do so without experiencing the high mortality associated with migration and (assuming the strategy is passed genetically) it will promote that trait over time...much like decreasing the number of years at sea, only to the extreme.
A fascinating subject, no doubt.