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New study on steelhead genes - "...up to 40% come from wild trout..."

5K views 73 replies 28 participants last post by  Jim Wallace 
#1 ·
Very interesting article:
http://oregonstate.edu/ua/ncs/archi...w-trout-critical-health-steelhead-populations

1-31-11

CORVALLIS, Ore. - Genetic research is showing that healthy steelhead runs in Pacific Northwest streams can depend heavily on the productivity of their stay-at-home counterparts, rainbow trout.

Steelhead and rainbow trout look different, grow differently, and one heads off to sea while the other never leaves home. But the life histories and reproductive health of wild trout and steelhead are tightly linked and interdependent, more so than has been appreciated, a new Oregon State University study concludes.

The research could raise new challenges for fishery managers to pay equally close attention to the health, stability and habitat of wild rainbow trout, the researchers say, because healthy steelhead populations may require healthy trout populations.

In a field study in Hood River, Ore., researchers used DNA analysis to determine that up to 40 percent of the genes in returning steelhead came from wild rainbow trout, rather than other steelhead. And only 1 percent of the genes came from "residualized" hatchery fish - fish that had stayed in the stream and mated, but not gone to sea as intended by the hatchery program.

"It used to be thought that coastal rainbow trout and steelhead were actually two different fish species, but we've known for some time that isn't true," said Mark Christie, an OSU postdoctoral research associate and expert in fish genetic analysis. "What's remarkable about these findings is not just that these are the same fish species, but the extent to which they interbreed, and how important wild trout are to the health of steelhead populations."

This research, just published in the journal Molecular Ecology, was based on a 15-year analysis of 12,725 steelhead from Oregon's Hood River, each of which was sampled to determine its genetic background and parentage. It was supported by funding from the Bonneville Power Administration.

The study reveals a complex picture of wild trout and steelhead intermingling as they reproduce. A steelhead might be produced by the spawning of two steelhead, two wild trout, or a returning steelhead and a trout.

Rainbow trout are small to moderate-sized fish in most rivers, but if that same fish migrates to the ocean it can return as a huge steelhead weighing 30 pounds or more, prized for sport fishing. Researchers still don't know exactly why some trout choose to go to the ocean and others don't, although they believe at least some part of the equation is genetic.

Studies of rainbow trout and steelhead have been undertaken, in part, to better understand the implications of hatcheries. Including all salmonid species, more than one billion hatchery salmon are released into Pacific Northwest streams each year. And because hatcheries produce fish that are less able to survive and successfully reproduce in the wild, there is concern about hatchery fish mating with wild fish.

"One implication of this study is that the genetic contribution by wild trout is diluting the input of genes from hatchery fish to the wild steelhead population," said Michael Blouin, an OSU professor of zoology and co-author on this study.

"The genetic influences of hatchery fish on wild steelhead populations are still a concern," Blouin said. "But the good news from the Hood River is that the hatchery genes are being diluted more than we thought, and thus may not be having as much impact on dragging down the fitness of the wild steelhead."

The genetic influence of wild rainbow trout, the scientists said, is roughly cutting in half the genetic input of hatchery fish that reproduce in the wild - a mitigation of their impact that's of some importance.

The scientists cautioned that results from one river might not be representative of all steelhead populations. Nevertheless, Christie said, "The importance of trout in maintaining steelhead runs should not be underestimated.

"They can act as a healthy genetic reservoir and preserve reproductive populations during years when ocean conditions make steelhead survival very difficult," he said. "So a good way of looking at it is, whatever is good for wild rainbow trout is also good for steelhead."

Worth noting, the researchers said, is that most other salmonids, such as coho or chinook salmon, do not have this type of fall-back system to help produce fish with a higher capability of surviving. As such, they may be more vulnerable than steelhead to the concerns about genetic weaknesses produced by hatchery fish.
 
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#42 ·
I apologize if this has been mentioned earlier, but I didn't actually have time to read all of the posts here.

If anyone spends any time fishing the Deschutes River down here in OR during the spring, no doubt they will have noticed that many of the redds are highly visible. just about all of the time there is a mix of redbands and steelhead. It's not really a shock to see a single steelhead on a redd with several redband trout and vice versa (Every year I witness this). So it stands to reason that they do indeed interbreed.

now, if we can just get the damn guides to stop sending clients over to dredge the water right on top of the redds so they can get into fish (I'm tired of getting cursed out every time I point this out to them)....but that's for another post.
 
#44 ·
#46 ·
I saw David speak this fall at the salmon summit in b'ham, bought his book and enjoyed it. Erveryone should read this book!
 
#45 ·
Leroy-

My original post was referring to this post of yours:

“The genetic influences of hatchery fish on wild steelhead populations are still a concern,” Blouin said. “But the good news from the Hood River is that the hatchery genes are being diluted more than we thought, and thus may not be having as much impact on dragging down the fitness of the wild steelhead.”

Could this mean that everyone may have to re-think there adamant hatred for hatchery programs and hatchery fish and dams ? Wouldn't that be a bitch if every yuppy blog had to drop that mantra ?????????????

By referring to the two studies and their results, I had hoped to illustrate:
1) the trout/steelhead study did not find that hatchery fish were any fitter than previously thought.
2) The previous study done with the same data is one of the most well-known examples of low fitness of hatchery fish and their offspring.
3) None of the studies address dams and their affects on population productivity.

Your original post quoted above seems to imply that the results of the trout/steelhead study should make people reconsider their thoughts about the poor fitness of hatchery fish or the effects of dams. Given the content of the body of research you are referring to, neither of the conclusions are accurate or appropriate. If you have issues with the methods or findings of either paper that you would like to raise, I am all ears.
 
#48 ·
There are problems with the Hood River study, Araki et al. 2007 paper in Science, where everyone gets the 60% figure they like to bring up. 1)If you go through the paper's data in the appendix, as I have, you find that the relationship is not strongly significant, only p=.1 for 1 tailed test. Doesn't hold up at all for two tailed. Could have been a stronger correlation if they had another point, but they don't. 2) The impression of a fit to the decrease in fitness per generation curve is increased by selection of data from other studies, while ignoring data from other studies that don't fit the line. But apparently a pretty graph like theirs that fits a popular perception gets you published in Science. See Berejikian's slides at http://www.ykfp.org/par09/ppt/sessiona/day2/html/Berejikian/siframes.html, particularly slides 6, 7, and 8. 3.) The dam on Hood River is out now, so there aren't going to be any more points.
 
#50 ·
Hey Paul,

I really want to believe you, but I would also like to have a formal rebuttal paper to read. You know you can publish this re-analysised data or simply point out the experimental flaws back to Science or Nature! Or better yet, make them retract their published paper from Science! This is how science work right?! We can have all kind of conclusions and opinions, all welcome. But most importantly, what is your evidence? if your evidence strong enough? This research use more sophisticate fitness model and yield multiple evidences about the reproductive fitness. Not just a single relationship you point out here. There are at least 4 papers in this series of study that all point to the same direction... who should I believe? you or this group? I strong encourage you to write up your paper and I am really looking forward to read it.

Mark
 
#49 ·
Paul-

First of all 60% was from one study in one river at one point in time...the number is likely to vary from river to river and time to time depending on the specific circumstances and chance. Regardless of the magnitude of decline, the paper reinforces what other studies such as the ones they have incorporated, show, which is lower fitness of hatchery fish reproducing in the wild relative to wild fish.

Second of all, the Araki paper and others passed peer review...Barry's powerpoint did not. Barry's powerpoint is very deceptive because many of the hatchery programs that he shows having similar fitness over many generations are integrated programs where during those generations a large % of the fish spawning in the wild were of hatchery origin, thus likely dragging down the fitness of the wild population...the very design of integrated hatchery programs is to maintain similarity of wild and hatchery fish...this maintains the fitness of hatchery fish in the wild because new wild genetic material is constantly being incorporated into the hatchery genepool, but, as a result of hatchery fish constantly spawning in the wild, and in many cases outnumbering wild spawners, the fitness of the wild population decreases, resulting in similar fitness of hatchery and wild fish over time, but utimately, lower fitness than what the fitness of wild population would have been if it had been left alone.

Looking at slide 8 in Barry's talk, he notes, "Ford et al found no difference in lifetime reproductive success of hatchery and natural origin coho salmon after about 13 generations of hatchery operation in Minter Creek. However, the naturally spawning population was clearly dominated by returning hatchery produced fish, so the comparison made in this study may reflect as little as one generation hatchery effects."

I would also point out that although there is alot of noise in the data, the mean value for fitness even for supplementation programs is significantly lower than for wild populations.
 
#52 ·
Actually, Yahina, the papers that I have read on precocial parr (in Atlantic salmon in eastern Canada before the end of their commercial fisheries) was in males, not females (this phenomenon is also being studied for chinook in the Columbia River system; it appears to occur in both wild and hatchery-released males). Because female reproductive success is so tied to number of eggs produced, being precocial (and producing a pittance of eggs) is not an effective female strategy; it is best to go out to sea where there are abundant food resources and to chance the gauntlet of predators and nets on the slim chance of returning to the spawning grounds as a very large, very ripe mature female. In the case of precocial males, over half the body mass of these little guys were testes; sperm are cheap. As the likelihood of returning via the anadromous pathway dropped, the percentage of precocial male parr increased (see Introduction to http://jhered.oxfordjournals.org/content/92/2/146.full) for example.

Steve
 
#53 ·
Steve,

You are absolutely right!

mature male parr is rare, mature female parr is even "rarier". The paper I have read is in Atlantic salmon in France 1985. they found about 17 % male parr could potentially produce sperms... and only 6% females parr have eggs, but most of them are not viable...

Sorry for the confusion. I just want to stress the point that even the female could have mature parr form. It is rare in the rare...
Thanks for the good description. I agree with you Steve.

Mark
 
#56 ·
I find this all very interesting in view of what has changed on the stilly over the years. Back when spotting a school of fifeteen to thirty or more summeruns in a drift was not unusual, like the seventies. The resident trout fishing was pretty good. I even had a partner who would go with me two three times a week and almost always just trout fished. In years past I was always greeted with the response that these were just smolts but of course the difference between smolts and native fish is quite obvious. He would often have good days on 8-12" fish from June on into October. There was even back then a pretty decent green drake hatch that would even get me to trout fish. The river here in front of these my house used to have a good population of trout and also smolts and small salmon at times. We had good hatches with the caddis larva thick as fleas. Now for many years that has been gone , the steel heading went bad about the same time the trout went away along with the insect life. All we see anymore is dogs, silvers and humpies and not too many of those. These changes would seem to reinforce this study. Of course that a river with a food supply that is gone has problems I guess is not rocket science or even marine biology.
 
#62 ·
which part is stupid. closing the program? or moving it to another river?

fyi, the decision was not based solely on the hood river study. anyone who went to the two public meetings in forks or read the data presented by wdfw and conservation groups would know that the hood river study was one small riffle in a river of science that shows broodstock hatcheries (and snyder creek specifically) are bad for wild fish stocks.

we can have a conversation about the place for hatchery fish, but we cannot pretend that they somehow help wild fish and/or wild fish recovery.
i attended both meetings in forks. The state didnt consider anything that was discussed at the first meeting.Show me where there has been reasearch done that shows either way weather or not the wild fish are being negatively impacted by broodstocking on the Sol Duc. ( Not trying to challenge you) I would just like to see it. If broodstock programs are so bad why move it to the Calawah or Bogie. Also the concept of a wild gene bank river is a great idea but the wdfw admitted that harchery fish from the bogie do go up the Sol Duc. I would argue that the river that should have been considered for a wild gene bank river should have been the Hoh river.

If broodstock programs are so bad than why is it that the Hoh tribe stopped planting chambers fish and went to a broodstock program.

I would also argue that NOAA doesnt agree with you about hatchery fish being used to rebuild wild fish runs. There are captive breeding population hatchery programs being implemented in a lot of places.
 
G
#59 ·
Okay I understand you guys love your studies but I have to ask. If the hatchery fish are so weak and disrupt the natives how do explain the Clearwater or Grand Ronde who have strong runs of both natives and hatchery fish? Why is it that the dams haven't decimated these runs? I don't understand.

Talked to a side drifting guide couple of days ago who with two clients caught 11 and 8 were natives at Heller bar in a 6 hour trip last week . He said the day before was slow 8 fish but they were all natives. When was the last time you heard of that on the Skykomish or Skagit? What happened?
 
G
#61 ·
fishing success is not always the best indicator of abundance.
Uh huh well I'm not talking about "always" I'm talking about the Clearwater and the Grand Ronde right now. Lot and lots of natives every year since I moved here 14 years ago. I came from fishing the puget sound and the peninsula rivers and am amazed at the numbers of fish per day the good fisherman can produce consistantly every year. Sure they aren't as fresh as a Hoh fish but to deny their numbers is just laughable. The Hoh has no dams and is too green to fish by anglers most of the spring and yet the numbers of Steelhead when it does come to shape are disgusting low compared to even the 30 years ago.

Why the success of those fisheries? Come on guys what's the deal?
 
#64 ·
i know the general response to this has been in another direction, but what popped into my mind initially upon reading this were fresh doubts about the reclassification of rainbows from s.g. to o. mykiss. i'm not an expert on the reasons for the change but it seems like this phenomenon is unique to rainbows/steelhead within the genus they are currently classified in, and it seems like a very significant distinction. the other species in that genus can exist in a landlocked state, but (correct me if i'm wrong) i've never heard of a population of any other pacific salmon besides o. mykiss inhabiting a stream except for landlocked fish spawning in inlets or outlets.

not saying salmo was the correct genus cause i don't know anything about that either, and maybe behaviors are not a factor in taxonomy, only physical traits? i don't know. but based on the article, it seems like behaviorally, rainbows have as much in common with bull trout (a char, obviously) as they do pacific salmon.

like i said, i'm not an expert so i'm just asking. i'm sure the many experts here can help educate me.
 
#66 ·
Fifafu,

Your 14 years is little more than a snapshot in time. After the Snake River dams (Ice Harbor, Lower Monumental, Little Goose, Lower Granite, Hells Canyon, Oxbow, Brownlee, and Dworshak on the Clearwater, the Snake River salmon and steelhead populations plummeted, with many being extirpated. The large runs you see now are only large relative to the time when they were nearly lost. The pre-dam runs were far larger. The current run sizes are the product of stocking millions - that's millions not thousands - of hatchery smolts. The better than average contemporary returns are the additional product of spring spill and above average ocean survival.

As bad as hatchery fish can be for wild populations, inland hatchery summer steelhead appear to survive better in the natural environment than their coastal Chambers Creek hatchery winter runs do. That is most likely because the spawn timing of the inland hatchery summer steelhead is about the same as the wild fish. That puts them a step ahead of the Chambers fish. All the other hatchery disadvantages still apply, but as hatchery fish survive in the natural environment, the subsequent generations apparently survive better, almost as well as wild fish with no hatchery heritage, as near as I can tell from reading some of the genetics study reports.

An important point is that these current wild inland steelhead runs are not large relative to the size of the respective river basins. The Grand Ronde is a much larger basin than is the coastal Hoh River, not to mention that the productivity per unit area of the Ronde is likely significantly greater as well.

Coastal and Puget Sound river steelhead are not having as good ocean survival as Columbia stocks, but that is a relationship that can and does flip from time to time. And has been discussed here considerably, PS river steelhead seem to be at an all time low for ocean survival.

I hope this added perspective helps you better understand the factors influencing steelhead abundance.

Dflett68,

Rainbow and cutthroat were moved from the genus Salmo to Oncorhyncus because improved genetic analysis (DNA) shows them to be phylogenetically linked to the Pacific salmon species more than the earlier Salmo species - Atlantic salmon and brown trout. And you're right, fish behavior isn't a factor in taxonomy. It's about body structure and meristics.

Sg
 
#71 ·
Dflett68,

Rainbow and cutthroat were moved from the genus Salmo to Oncorhyncus because improved genetic analysis (DNA) shows them to be phylogenetically linked to the Pacific salmon species more than the earlier Salmo species - Atlantic salmon and brown trout. And you're right, fish behavior isn't a factor in taxonomy. It's about body structure and meristics.

Sg
Thanks SG. Seems like you can almost just look at rainbows and cutts versus browns and atlantic salmon and see they are more like Oncorhyncus than Salmo, so I can see how the existing genus was deemed inaccurate. But at the same time it seems like they have nearly as many distinctions from the other members of Oncorhyncus as they do from those of Salmo. Of course, I don't know phylogenetics or meristics are, and I'm too lazy to look it up at the moment, so I'll trust the taxonomists. But I will also publicly note, as I have privately, your obvious feelings of nostalgia for the old Salmo G, which I share.
 
G
#68 ·
Did you not read my original post? I said they are catching natives at 3 to 1 ratio. By the way it about the same in the Hanford Reach.

What is the deal? How can they be thriving if all the hatchery fish are being planted? I'm still missing how there can be that many natives in Idaho but not in Forks? If you claim these are unclipped hatchery fish you haven't put your hands under a B-Run.

Sorry I just don't get it.
 
#69 ·
Fifafu,

A lot of hatchery fish have been caught by January, so that would increase the wild:hatchery fish ratio, but probably not by 3:1. Then you have the fact that wild fish bite better than their hatchery counterparts based on a Deschutes River creel census from a few years back. So wild fish show up in the catch out of proportion to their actual abundance. And this might be an attribute specific to the inland rivers, I don't know. But Freestone mentioned to me that the vast majority of their catch in the winter and late winter consists of unmarked fish in mid-C tribs, so the same thing may occur in the Snake and Clearwater as well.

If you read my earlier post you should know why there can be more wild steelhead in Idaho than in Forks. What is it you're missing?

Sg
 
#70 ·
Fifafu, just because more wild fish get caught than hatchery fish doesn't mean that they are thriving. It simply means that they bite/get hooked more and several studies support this. I've read that wild fish get hooked 10:1 over hatchery fish. I've had days when I hooked 10-20 fish and they were all wild endangered fish so no way in hell are they 'thriving', they're just biting...

And like salmo g says, the rivers you mentioned used to have way more fish. Think of it this way: if you are used to making $100,000 a year and then you lost your job, became homeless and had to live on $100/year for many, many years, you'd suddenly feel almost rich again if you made $1000/year. It's all a matter of perspective. The wild summer runs are still very much in trouble. Did you ever wonder how many more wild fish there might be if there were no hatchery fish?
 
G
#72 ·
If you know they are endangered why are you guys out there harrassing them? If I thought they were endangered I wouldn't pull 20 of them to shore.

Maybe the Endangered Species List is wrong. Is that possible?
 
#73 ·
The fishery is open specifically to pull out the hatchery fish so they don't spawn with the wild fish and NOAA and WDFW wants us to do this; so much so that it is actually illegal on to release the hatchery fish on the Upper Columbia and tribs. NOAA has determined what percentage of hatchery fish need to be removed and how many wild fish can be landed during the season before they shut the season down due to wild fish accidental mortality, which they just did this past weekend. It is a highly regulated and monitored fishery. The wild endangered Upper Columbia steelhead are years away from recovery as they are not successfully replacing themselves. The hatchery fish hurt their recovery chances but for reasons too complicated to explain, must continue to be planted so all we can do is remove as many of the ones that return as we can.

I, for one do, do not like to or want to catch wild endangered fish but I do want to get the hatchery fish out of the river. I did not say I landed 20 of them in a day, I said 'hooked' them. When I see that I am starting to hook wild fish, I try to get them up on top as quickly as possible to determine if they are hatchery or wild. If they are wild, I try to break them off or bend the size 12-16 hook I am using and not have to land them. If neither of these work, I horse them in as fast as possible, and I do mean horse them in. I broke my favorite steelhead rod doing this last season because I am pretty serious about doing the least harm I can while trying to get the hatchery fish out of the system. My point is do not assume a fish population is 'thriving' just because people are catching what you or they consider to be large numbers of wild fish. While our Columbia & Snake River summers runs may be larger than the Puget Sound runs, as salmo g pointed out, you are comparing apples and oranges as far as the river sytems and the number of fish that they can and should have returning. The Upper Columbia steelhead runs are still classified as at medium to high risk of extinction in the next 25 years...
 
#74 ·
Interesting stuff. i wish I would have known about this ten years ago. I released the biggest steelhead I ever caught. It was a beautiful, colored up hatchery buck in primo condition, that measured over 35" and that I landed in a smaller coastal stream that has no hatchery, but receives plants of smolts. I released it thinking that it would be great if this awesome fish was able to spawn. I had caught and bonked a similar fish the day before from the same pool, that measured 34.5" and weighed just under 14 lbs (dressed, with head intact). Man, I sure used to nail 'em with roe!
 
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