Skagit River Steehead

Discussion in 'Steelhead' started by Andrew Lawrence, Nov 27, 2012.

  1. Very interesting. Not sure how much I understand. Would like to see the presentations explained by those that put it all together.
  2. The links should be working now.
  3. Kerry,

    Thanks to more extensive genetic sampling than we've seen before, it means that introgression of hatchery genetic material is more widespread than we previously thought. The Skagit still has pure native wild steelhead, but a significant proportion of those wild steelhead are "less pure" than we expected them to be.

    Is that a problem? It depends on the definition of the problem.

  4. They worked for me when you first put them up. Like I said I would love to see the data collectors and creators of the presentation do them with interactive questioning.
  5. Sort of what I thought. Thanks for the added clarification.
  6. Based on what they have found, seems pretty obvious why wild fish struggle to do anything except decline. They are pretty good at that. This is a problem on so many levels...I hope the results are not politically twisted to eliminate wild fish for good. As it shows there is success using zoo raised steelhead to 'supplement' wild stocks. Too bad these zoo raised fish are supposed to be temporally separated from the 'wild', later returning portion of the population.
  7. Kerry/Salmo g

    Not so sure that this increased information is showing that the hatchery introgression is more wide spread than thought. In fact several genetists that I have had conversations with about this study remain unsure what this information exactly means.

    One problem - Across the PNW it has been consistently demostrated that natrual spawning Chamber's Creek hatchery winters have consistently been unsuccessful in producing returning adult fish. If that is indeed the case (and one would expect they would be even less successful in the Skagit) how are those fish with 20 to 50% hatchery markers being produced?

    In recent years the focus in the hatchery/wild debate has shifted from genetic introgression question to one of ecosystem interactions. Are the off spring of the natural spawning hatchery fish (whether mating with other hatchery fish or a wild one) competing with the wild juveniles before they die. The sampling of the juvenile fish in the cited Skagit study should provide some insight in this question. I do find it interesting that very few of the fish sampled in the wild had the high hatchery marker rate that one sees with the hatchery fish that are spawned at the hatchery. Not sure what the means or does anyone else I have talked with. It does suggest that more detailed studies are needed directed are more refined questions that spring from this study.

    Something to keep in mind - during theperiod the fish sampled for this study there was significant temproal separation between the hatchery and Skagit wild winters. Even one were to extend the potential spawning of the hatchery fish 6 weeks beyond that seen at the hatchery they could only potential interact with less than 5% of the Skagit wild population.

  8. Smalma,

    I think it has taken a large increase in sampling to detect more than the occasional hatchery marker. Then there is the notion that as Puget Sound steelhead, the Chambers Ck fish normally have 97 or 98% genetic commonality with other PS steelhead. The picture is not crystal clear, but that the markers that turn up seems to be within the range of reason to me.

    Ad clipped steelhead have been caught through March, and I've caught one or two pre-spawn males in early April. The probability of some cross-mating is entirely feasible. And while survival is expected to be low, statistically no different than zero, doesn't mean that none ever survive to return and spawn as adults.

  9. I attended a meeting a year or 2 where Mr Pflug spoke about this study. I had a couple of thoughts at that time and a few more now.

    1.) C&R angling has an effect so small on the fish that mentioning it or trying to restrict/reduce it is just plain dumb. These fish were caught and then had a rather large reciever shoved down their throats. It stayed inside the fish for weeks or maybe even months. The fish lived pretty much every single time. I believe only 1 or 2 fish died. The sample size was pretty darn large. I believe it was over 100 fish.

    2.) The hatchery fish smolt and outmigrate out of the Skagit at the same time and just before the bulk of the wild fish. Given the difficulty these fish are having leaving PS this may be a real important peice of the puzzle, especially with relation to predation. Ecosystem effects can happen outside the river too.

    3.) It seems like we really don't know why there is introgression at all. Given the low numbers of returns and the few hatchery fish that make it past nets, anglers and the hatchery itself what fish are left to spawn. They aren't known to spawn succesfully often either so how is there a measurable amount of introgression. My thought is that we are seeing the residualized smolts spawn with the wild fish. When you release 200,000- 500,000 hatchery fish some must residualize.

    4.) 200,000- 500,000 hatchery smolts and you get 1 or 2 thousand back? Doesn't seem worth it given that I can't see 1 possible positive impact of hatchery fish on wild fish.

    5.) Hopefully we get 10,000 fish back this year. That would be nice to see wouldn't it?

    Go Sox,
  10. Salmo g -
    I too have caught unspawned hatchery Chambers Creek fish in early April. However that was in the early 1970s when the hatcheries routinely spawned the hatchery fish through most of March. In the early 1980s between 10 and 15% of the Chambers Creek fish caught in the Skagit recreational fishery was in the month of March. By the mid-1980s the standard hatchery practice in the region was to end the spawning of hatchery fish before the end of February. By the early 1990s the spawning ended before mid-February and today the spawning of hatchery fish is completed by the end of Janaury. The time of the year and the year we saw those late spring hatchery fish is probably important.

    Clearly the WDFW's hatchery program has changed over time largely driven by the desire to reduce the potential for interaction between the hatchery and wild fish on the spawning grounds. There is a tendency for some folks to view the hatchery program as static rather than give potential credit for the State's efforts to address some of those concerns.

    I do find it pretty interesting that the limited genetic sampling/testing availble from the mid-1970s, the mid-1980s, the mid 1990s and this latest work all show approximately the same amount of so-called hatchery genes in the wild population over the past 40s with little change in spite of the signifcant reduction of temporal spawning over lap between the hatchery and wild fish. The would seem to support that the genetic similarity between the wild and hatchery fish may be from shared ancestors rather than interactions on the spawning grounds - of course that would not fit the agenda of some.

    In the last decade or two there is some thought (and indications) that those spring hatchery winter fish may be out of basin strays from the Vedder program. The share similar run and spawning timing as well as phenotypes.

  11. While Chambers/Chambers wild spawners are largely unsuccessful, Hatchery/Native spawners have been proven effective at spawning, its just that their offspring have a lower overall fitness. By the time that the % of hatchery genes is down to 25% you know its Likely an F-4 if you asume that the "Natives" arent purely native. At F-4 fitness differences are much less detectable. Especially in a river system that lacks serious environmental stressors like the Skagit which lacks significant waterfalls, canyons etc. Not like the (FORMER Elwha, where the falls, and canyons selected for the largest Chinook this planet has ever seen, or theDean for example) Another thing to consider that I saw 1st hand at Kendall creek is the integration of natives into the hatchery gene pool. Any natives that wander up the weir to spawn are included, and as such, the hatchery run gets an inadvertent small% of native genes( How do I know they were native and not unclipped you say? Native Nooksack fish look pretty distinctly different than the hatchery brats that make it back, in both size, spotting and overall fin condition. In 2008 when I was spawning there and we hat atrocious return #s we integrated 2 native bucks into the gene pool.
  12. The poorly timed smolt releases are likely a large contributer to cause for high residualization, and had I stayed in fisheries bio I would have done my thesis on this. Looking into a circular cement pond at 1000s of steelhead fingerlings swimming against the current for months, and then suddenly seeing them SWITCH direction and attempt to swim "downstream" one day is pretty dramatic, and its my opinion, that as soon as that happens, the fish should be let go, NOT held for maybe another month till the state decides its an overall better time for release. I have a whole experimental protocol worked out to prove that this would be a more effective method, if any fisheries bios are interested. There are far too many fin clipped 12-19" "rainbows" in many rivers just upstream and downstream of hatcheries to ignore this
    TD likes this.
  13. Interesting post SS. There is a tributary to the NF Stilly that I push back into during the lower summer flows. I used to be amazed at the 12+ inchers with clipped fins that I find back in there. Anymore, I can tell every time I hook one that it is going to be a clipped steelhead/rainbow. They pull like gang-busters and never quit. They are acrobatic and when finally bring them to hand they are gorgeous. I've pushed back in there at several different times of the year hoping and praying to find Wild Steelhead up in there but have never had it happen. I'm not surprised as this trib is above Deer Creek, still, I like to think that one day I might find them in there.
  14. Smalma,

    Good points about changes to fish culture. Indeed it's been a while, like 20 years, since those April hatchery fish. Interesting notion about Vedder strays; I hadn't thought of that.

    I wish agendas were restricted to meetings. The only legitimate fisheries agenda is to "seek the truth, and go where it leads us."

    orangeradish likes this.
  15. I know of a couple stray, mint bright and most certainly unspawned hatch fish caught in '06 in April. Vedder was brought up as the likely source.

    Precocious hatch males staying home and spawning with the wild females. Hmm...smells like a possible smoking gun....
  16. Pretty
    Pretty sure I know JUST where you're talking about ;)
  17. Stilly Stalker -
    The best criteria for releasing smolts has been studied quite a bit. As one of the graphs in the presentations provided in links in the first post in this thread shows the wild smolts migrate over a fair period of time (from late March to mid-June with the peak migration in the 2nd or 3rd of May). As often is the case in the biological world there is a fair amount of variation year to year.

    You are correct there always seems to be some hatchery smolts that want to leave early and begin actively crowding the ponds screens trying to leave. When those screens are pulled and the smolts are allowed to leave what typically seen is that 10 to 15% of the fish leave in a few days and then the out migration essentially stops until well into early May when there is pretty much a mass exit of smolts over 10 days or so. The State's guidelines call for some specific size and condition goals for the fish to be release and calls for the fish to be released in early to mid-May. On the whole the various studies as well as extensive experience has shown that following those guidelines result in the highest number of fish smolting and leaving the river in a very short period of time (often migrating from Marblemount to Mt. Vernon in just a couple days) as well as reducing the numbers of precocious males and hatchery fish that become resident fish.

    Are those guidelines prefect? of course not but for most situations and most years on the whole it works the best. To my knowledge the various folks (HSRG, FEds, etc) that have reviewed those guidelines have endorsed them. Here on the north Puget Sound rivers there is an added benefit from the early/mid-May releases and that is the start of the spring run-off. On rivers like the Skagit some of highest average daily flows accure in May and June. The snow melt not only speeds the smolts on the way it also creates a difficult environment for those fish that do not smolt reducing the likelyhood that they will become residals.

    For whatever reason it seems that the summer fish are more likely to produce a lower % of smolts than the winter fish.

  18. I know what you're saying.... But smolt release timing is based on S. Washington, and not the northern rivers. Optimum SMS reads timing should be determined on a watershed to watershed basis. NO GENERALIZATIONS
  19. That should read smolt release. Damn phone

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