Steelhead Science?

Discussion in 'Steelhead' started by prosopium, Nov 2, 2005.

  1. prosopium

    prosopium Member

    Since the topics of taking wild steelhead out of the water and the new regulations to kill hatchery Methow river steelies seem to be pretty controversial in the forum lately, i was wondering if anyone knows where the science behind it is. Ive been looking around quite a bit trying to find something and have found nothing. Since they are both somewhat controversial topics i thought there should be some science behind it. Does anyone have any clues? Thanks
  2. Porter

    Porter Active Member

    Yes...but I forgot all the reasons. This has been discussed before. Native vs. Hatchery
  3. TomB

    TomB Active Member

    I don't know that there is any science behind the removal from water rule. The rational is, I think, that it prevents people from dragging fish up on rocks or boat bottoms, holding them out of water for long periods, etc.

    In terms of killing hatchery fish, there is ALOT of science in this regard. Many hatchery strains are non-native, so these genes are obviously bad for a wild run when inter-breeding occurs because they have been selected to survive in a different environment and thus, the fish they produce are ill-equipped to survive in the stream in which they are planted.

    Even if hatchery stocks are in-basin stocks, they have several problems.
    1) genetic- they have poor genes and fitness which can be transferred in to wild populations via hatchery x wild crosses, because their reproduction is not selected for naturally, but rather by humans, furthermore, the selective pressures on juveniles are different than wild juveniles because of the environment in which they are raised.
    2) Competition- hatchery fish compete for limited resources with wild fish in virtually every stage of their life, and although they are usually inferior competitors, their sheer numbers can have a detrimental effect on wild populations.
    3) Predation- hatchery fish can eat wild juveniles which is obviously bad for wild populations.

    if you want papers on this I can provide you with at least a few.
  4. John Hicks

    John Hicks Owner and operator of Sea Run Pursuits

    Well, I don't know if this is gospel or not but I was told and have read that a fish's internal organs are used to being in an environment that supports them, i.e. water. Now you take a fish out of the water especially a large one the organs are not supported as they would be in the water and this can harm them. Just my 2 cents

    john Hicks
  5. TomB

    TomB Active Member

    John- I think that is definately possible...most of the time it is probably not an issue, but it is encompassed by the "etc" is my post regarding reasons for the rule.
  6. prosopium

    prosopium Member

    Thanks TomB for your input, what i am looking for is hard science (not fishermans opinions, or things they have heard), so it would greatly be appreciated if you could send me some links to some peer-reviewed journals. Sorry to everyone about posting this twice i was having some computer problems earlier and im also sorry if you think i might be 'beating a dead horse' on these topics since it seems they have been covered a lot lately but im trying to use this information for some stuff in school.
  7. TomB

    TomB Active Member

    after a quick search, here are a few citations:

    McLean, Jennifer E.; Bentzen, Paul; Quinn, Thomas P.
    Differential reproductive success of sympatric, naturally spawning hatchery and wild steelhead, Oncorhynchus mykiss
    Environmental Biology of Fishes 69 (1-4) : 359-369 March 2004

    Levin, Phillip S.; Williams, John G.
    Interspecific effects of artifically propagated fish: An additional conservation risk for salmon.
    Conservation Biology 16 (6) : 1581-1587 December 2002

    Nielsen, Jennifer L.; Gan, Christina; Thomas, W. Kelley
    Differences in genetic diversity for mitochondrial DNA between hatchery and wild population of Oncorhynchus
    Canadian Journal of Fisheries and Aquatic Sciences 51 (SUPPL. 1) : 290-297 1994

    McLean, Jennifer E.; Bentzen, Paul; Quinn, Thomas P.
    Nonrandom, size- and timing-biased breeding in a hatchery population of steelhead trout
    Conservation Biology 19 (2) : 446-454 April 2005

    The effects of hatchery and wild ancestry and experience on the relative ability of steelhead trout fry (Oncorhynchus mykiss) to avoid a benthic predator


  8. John Hicks

    John Hicks Owner and operator of Sea Run Pursuits

    Tom you are my God! That was amazing pulling all those facts was amazing. I will bow down to you forever.
  9. TomB

    TomB Active Member

  10. John Hicks

    John Hicks Owner and operator of Sea Run Pursuits

    Dude! No I am very impressed with your deft ability to answer him. bravo!

  11. Smalma

    Smalma Active Member

    Something to keep in mind when reviewing the various literature is that what may be true about one species may or may not be true about another. For example chinook smolt behavior would be expected to be different than that of other species. One would not expect hatchery pink fry to be much of a predator on other species - competitor yes.

    Our steelhead and other anadormous fishes live in very dynamic and diverse habitats so again it may not be wise to expect what is true in one envirnoment to necessarily hold true in another. For example the work in the Maclean paper was on Forks Creek a trib to the Willapa - a coastal stream with early returninng and spawning wild fish. One may see different hatchery/wild interactions in a system where the hatchery and wild populations of different charactistics than those in the study stream.

    Tight lines
  12. TomB

    TomB Active Member

    Curt- as always, a good critique....I was simply providing him with the first citations I could come up with so he could do some reading...there is alot out there to consider, and none of it applies universally.
  13. John Hicks

    John Hicks Owner and operator of Sea Run Pursuits

    Tom thank you and can't wait to slap some water with you.


  14. TomB

    TomB Active Member

    Sure thing buddy!
  15. prosopium

    prosopium Member

    Thanks for all of the sources Tom, ill look into them. But do you know if there are any papers published that distinctly target interactions between hatchery and wild steelhead in the Methow River system, that supports the "voluntary" keeping of fish of hatchery origin. It makes sense to me but im just trying to find real facts or information regarding interactions between the two.
  16. TomB

    TomB Active Member

    To my knowledge I don't know of any published papers of research done on the methow on this subject-there may be/probably is data on this that has been collected by NOAA since the listing a few years ago but I don't think it has been published in any journals. I know there was a paper published on this subject that took place on the kalama, which is a columbia river trib, so that is definately comparable, but I can't find that citation.

    The methow situation is perhaps more complex than others because of the degree of genetic introgression that has occurred between wild and hatchery fish. In the case of several washington steelhead streams, little introgression has occurrred though, making its prevention that much more important (i.e. the need to bonk brats).
  17. Porter

    Porter Active Member

    TomB you are becoming the search engine for crettke....he needs to do a little exploring himself. You do have the goods....that's for sure.
  18. Jason Rolfe

    Jason Rolfe Wanderer

    I'm always impressed when I open up one of these threads and see some well researched and thought out reply. You are definitely someone who takes this stuff seriously and I think it's something to be proud of. There's a lot to be said for someone who takes the time to think a little harder about something.
    Jason Rolfe
  19. prosopium

    prosopium Member

    Thanks Tom, ive spent numerous hours looking into the Methow stuff and have found nothing but it sounds like that might be because there is nothing, which is hard to believe. Im no expert in navigating the NOAA sight but i did spend some time trying to find anything but failed. If you are ever interested in finding any information regarding whirling disease or cutthroat hybridization send me an email and i could get you all the sources you need, its the least i could do to pay you back since i am getting a bad rap for asking the question and supposedly not researching for myself. If i find the info and do the project i promise ill put your name in there, thanks again.
  20. TomB

    TomB Active Member

    For the NOAA stuff, you might try contacting employees because alot of the data is on computers and in reports that aren't accessible really.