Wild steelhead vs Native vs ?

Discussion in 'Steelhead' started by Kaiserman, Oct 28, 2011.

  1. Kaiserman content

    Posts: 2,635
    Ratings: +437 / 0
    There is a river that I like to fish for steelhead that no longer is getting hatchery plants as of last spring. The reason is because of the inter breeding of the hatchery fish with the "wild/native" stock. I say stock, because it is just that. After many discussions and e-mails, it's been obvious that there is no real strain left of the wild/native fish in the river. Meaning that the wild/native fish that are there now, are nothing more than a compilation of "test tube" fish. There hasn't been a true generation of wild/native fish in there for decades, they're "manufactured" fish...including the hatchery ones.

    My question is, why? Why then would they all of a sudden just think that a manufactured fish is going to turn wild? Can that happen? Common sense says that it can be, but from what I've learned from the studies that NOAA has put out over the past couple of years, it can't be - or at least they say. Can the "hatchery gene", if you will, be bred out over a few generations? I guess it makes sense to shut the river down if it can be. However if it can't be, and they know it can't be, why do this? Doesn't it seem kind of hypocritical to manufacture a fish...just to call it "wild or native"? Doesn't this just seem to look like window dressing?

    Anyone have any insight?
  2. Freestone Not to be confused with freestoneangler

    Posts: 2,366
    .
    Ratings: +1,215 / 0
    You seem to be using the terms interchangably and that may be causing your confusion. The words really aren't interchangable for the question(s) you are asking. A wild fish is simply born in the wild, regardless of genetics. Hatchery x Hatchery spawning in the river = wild babies. Native refers to the original stock/genetics of the river. Hatchery fish with out-of-basin genetics may have wild babies, but those wild babies will never be native (genetically).

    Will the river ever have pure native, wild fish again? I wouldn't be so quick to assume that there are no native genetics left in the river but that is a much more complicated answer...
  3. Chris Johnson Member: Native Fish Society

    Posts: 1,796
    Bellingham Wa.
    Ratings: +320 / 1
    From Chilcote 2011 study:

    "The magnitude of
    this negative relationship is such that we predict the recruitment performance for a population composed entirely of hatchery
    fish would be 0.128 of that for a population composed entirely of wild fish. The effect of hatchery fish on reproductive
    performance was the same among all three species. Further, the impact of hatchery fish from ‘‘wild type’’ hatchery broodstocks
    was no less adverse than hatchery fish from traditional, domesticated broodstocks. We also found no support for the
    hypothesis that a population’s reproductive performance was affected by the length of exposure to hatchery fish. In most
    cases, measures that minimize the interactions between wild and hatchery fish will be the best long-term conservation
    strategy for wild populations"
  4. Kaiserman content

    Posts: 2,635
    Ratings: +437 / 0
    Thanks Freestone. I think I knew the difference, but now I'm sure I do. Funny how you go through life "knowing" an answer, yet you really don't. Thanks for clarifying that.

    Well then, that would explain why they are doing what they are, and it isn't so hypocritical as I stated. I think you may be right about the true genetics thing. However, one of the biologists I ran into on the river responded that he didn't think so. If there was, it was unmeasurable. We'll see I guess.

    What's really funny, is that about 7 years ago 20 pairs of Sockeye came up the river to spawn. They did, and there was no return. It was exactly 20 yrs since the last time a Sockeye had returned to that river. The biologists couldn't figure that one out. They had never planted any Sockeyes, and the 20 (from what I remember) were not hatchery fish.
  5. Chris Johnson Member: Native Fish Society

    Posts: 1,796
    Bellingham Wa.
    Ratings: +320 / 1
    If the habitat is there, salmon will repopulate it. That is how they have survived for hundreds of thousands of years in a young and changing geology like the pacific northwest.
  6. Kaiserman content

    Posts: 2,635
    Ratings: +437 / 0
    I understand that Chris, I just thought it weird (as did the bio's) that 20 pairs showed up after 20 yrs, then never came back...and haven't since.
  7. Chris Johnson Member: Native Fish Society

    Posts: 1,796
    Bellingham Wa.
    Ratings: +320 / 1
    Yes, that is weird.
  8. freestoneangler Not to be confused with Freestone

    Posts: 4,138
    Edgewood, WA
    Ratings: +791 / 1
    Good point sister!
  9. cabezon Sculpin Enterprises

    Posts: 1,722
    Olympia, WA
    Ratings: +244 / 0
    I'm not sure that this really is weird. After all, salmon are known to stray. This has been a key part of their strategy for invading newly-opened rivers in a region impacted by glaciers. It might be strange that 40 individual fish strayed all the same year, but it wouldn't be strange if one school strayed. After all, a single salmon could not jump-start a new population; it takes a minimum of two of the opposite sex to tango. Stochasticity (randomness) is a hard concept for humans to grasp; a rare event, a one in 50 year event or even longer, such as this one, could be sufficient to start a new population if the spawning habitat and rearing conditions were acceptable.

    Steve
  10. cabezon Sculpin Enterprises

    Posts: 1,722
    Olympia, WA
    Ratings: +244 / 0
  11. Kaiserman content

    Posts: 2,635
    Ratings: +437 / 0
    Yeah Steve, that's what the e-mail indicated (the cross breeding). I too have learned that the combinations (hatchery x wild) has a low survival rate. That's why I was posing the original question. Can that "dumb" gene get weeded out after a couple generations? Maybe that's what they are going to find out. I don't live on the west side, but over here...they haven't losed waters that steelhead in them for a long time, if ever. They haven't done that yet, but they are no longer planting hatchery fish anymore. My guess, and the biologist I talked to, thinks they may.

    As far as the Sockeye go, I know they wander too. I think it was the amount of time that had passed, and how many, that struck those guys as odd. That coupled with no returns at all since...no other "strays" if you will.

    Thanks for your insight too. :thumb:
  12. kamishak steve Active Member

    Posts: 359
    Seattle, Wa
    Ratings: +67 / 0
    In response to the "dumb" gene question:

    Whatever adaptations to that specific watershed the native fish have, typically will be those selected for even among the hatchery brats. for example, if lets say the shape of a particular river best suits fish that are long and slender (a lot of summer run rivers are this way) where ascending through canyon sections and waterfalls produces native fish that are normally long and slender. If you were to pump that river with fish that are normally much fatter in a hatchery program scenario (like skamania fish they use in hatcheries here), the hatchery fish that produce the most successful offspring, will likely be the most long and most slender fish of that hatchery breeding population. The fish will reevolve to those characteristics, it will just take a very very long time to do so, as many of these evolutionary selection processes for steelhead within a particular river may be several thousand years old.
  13. thesankers Member

    Posts: 110
    Richland, WA
    Ratings: +8 / 1
    Genetic studies in Minnesota and Ontario have shown that there are genetic differences between steelhead running in the various streams on the North Shore of Lake Superior. The fish have been there for <150 years. So, adaptive changes can happen pretty quickly. These studies were a part of the decison by Minnesota to stop stocking any steelhead in the 90's and let the fish fend for themselves.
  14. fredaevans Active Member

    Posts: 3,131
    White City, Oregon, USA.
    Ratings: +124 / 0
    That's one of best bits of 'intulectually' puils off fluofff i've rud in yars. I read 'something' like this and the first thing that tends to cross my mind is if the 'Author' has Blue eyes it just means he's a quart low .....

    "Hatchery fish with out-of-basin genetics may have wild babies, but those wild babies will never be native (genetically)."

    Agree, and that's what I like about Southern Oregon Rivers (can't speak to the stocking practices in the north half of the State) but all the hatchery brood stock comes out of wild stock from the same river. Me thinks that adds much to the Party.
    fae
  15. Kaiserman content

    Posts: 2,635
    Ratings: +437 / 0
    That's how they do it in this river too, so I'm told by the biologists.
  16. cabezon Sculpin Enterprises

    Posts: 1,722
    Olympia, WA
    Ratings: +244 / 0
    Here is a scenario, a thought experiment. Let's take the brood from a single pair of parents and split it in half. Half is deposited in the gravel exactly as normal; half is deposited into an egg-tray at a hatchery. The wild eggs are exposed to variation in temperature, oxygen, exposure to pathogens; many eggs do not complete development (die) and some genes are turned on and others permanently turned off among the survivors (a topic called epigenetics). The hatchery eggs experience relatively constant temperature and oxygen and minimal exposure to pathogens (but they may have exposure to antibiotics); most hatch. For the next year, the overwhelming majority of the wild steelhead will die; some from chance events, some because they are not as well-adapted to their environment as the survivors. The survivors learn what is (and isn't) food (or die) and where to hide to avoid predators or adverse water flows (too much or too little) (or die). They become territorial to preserve their food. More genes are turned on and others turned off. The hatchery survivors also learn what is food (pellets), but they do not have to do much to avoid predators and they tolerate tight packing. Some genes are turned on and others turned off, but these patterns are different from those whose regulation was adjusted in the wild fish. After a year, the hatchery fish are now released to the same environment as the wild fish. But these fish are not the same. Yes, the basic DNA may be similar (although selection has likely changed the gene frequencies between the two groups - a concrete raceway is not equivalent to a stream). The control of genes is likely to be dramatically different too. This may impact growth, survival, and reproductive success when the survivors from each group returns. Now the returnees of both groups spawn in the gravel. But epigenetic effects can persist for generations afterward. Bottom line. 1) Rearing wild fish in the hatchery environment certainly selects for genes that are different than those selected for in fish growing in the wild. 2) Changes in epigenetic effects can last for multiple generations, becoming less important with increasing number of generations.

    Epigenetics (beyond the genome) is the study factors that impact the regulation of genes (DNA). It is a very active area of research and the picture is far from complete. Here is a link to wikipedia's entry on epigenetics: http://en.wikipedia.org/wiki/Epigenetics and a great PBS program on the subject: http://www.pbs.org/wgbh/nova/body/epigenetics.html. There are well-known studies of human epigenetic effects that impacted multiple generations. One study traced the survival and health of Dutch children conceived in 1944 during a period when the Germans denied food to some towns because of partisan activity; individuals who were developing in utero during this period were smaller than those in other towns outside German control and these effects were passed on to their children as well as an increased risk of schizophrenia (see http://en.wikipedia.org/wiki/Dutch_famine_of_1944#Scientific_legacy). Similarly, a study of the population of a small isolated town in Sweden (Overkalix) demonstrated that epigenetic effects impacted daughters differently from sons and varied depending on available food (see http://en.wikipedia.org/wiki/Överkalix_study).

    Of course, salmon have not been studied for epigenetic effects..... yet. But epigenetic effects are well-documented in many species. Generally, they are driven by environmental factors (stresses), they impact the biology of the individuals who experience them, and the effects can impact future generations. Thus ends today's biology lesson.

    Steve
  17. Chris Johnson Member: Native Fish Society

    Posts: 1,796
    Bellingham Wa.
    Ratings: +320 / 1
    It sounds good but this study shows no benefit to broodstock programs. They have been doing this on the north fork Nooksack for years with spring chinook, they get a good return but they don't seem to reproduce(0.128 fecundity). Mining wild fish to make hatchery fish is a bad idea in most cases(IMVHO). If you have some literature that show a different result I'd like to read it.
    I can send you the Chilcote study or you can see it on the nativefishsociety.org

    Chris
  18. Smalma Active Member

    Posts: 2,839
    Marysville, Washington
    Ratings: +717 / 0
    Cabezon-
    While not as detailed as some human studies I believe that epigenetic effects have been demostrated in salmonid. For example it has been know for decades that the water temperature during the incudbation of trout eggs can influence such mertistic counts as vertebrae or scale numbers. More recently there is developing information that O. mykiss fry/parr are more likley to adopt the resident life history rather than the anadromous life history when rearing temperatures are higher.

    Chris -
    While it is correct that those natural spawning NF Nooksack spring Chinook are not very productive that productivity maybe limited more the carry capcity of that system than the origin of the spawners. It seems regardless of the numbers of spawners the systems seems to be capable of producing only a few hundred adults.

    As always when it comes fish and their genetics issues can be very complex. The role of the exteme natural selection that takes place in salmonid populatins can not be over looked.

    Tight lines
    Curt
  19. Chris Johnson Member: Native Fish Society

    Posts: 1,796
    Bellingham Wa.
    Ratings: +320 / 1
    Curt, thanks for your response, having very limited knowledge on the subject I always appreciate educated answers. In respect to N.F. Nooksack spring chinook, If carrying capacity is the limiting factor, it begs the question, why continue the program?
  20. Paul Huffman Lagging economic indicator

    Posts: 1,434
    Yakima, WA.
    Ratings: +148 / 0
    Yes, but here's another thought experiment. Half the eggs are deposited in the gravel exactly as normal. A duck finds the nest and eats 95% of them. Or a skulpin. Or a big winter flood. There's no selection for the fittest egg. It's just bad luck. No chance for the most adaptive, fast, or smart fry to survive the selection process to pass on their superior genes to the next generation, because they died as eggs. On the other hand, the eggs in the hatchery have 90 times the egg to fry survival, thanks to improvements in hatchery design and practice: redundant water systems, flow alarms, disease management.