Triploid trout

[killperch]

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[fish1on]

Interesting post...I will have to educate myself more before I can give you my opinion!
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[superslammer]

That is a very interesting point you have made. I went to the F&G website and read some of the articles and studies about triploids. It seems to me that they might be less aggressive. I agree with your comment that it probably is fine to stock genetically altered triploids in waters that contain native endangered species of fish. All the other waters, I think, should be stocked with diploids. This gives those waters a chance for the fish to reproduce on their own and make for a more aggressive fish to catch. "Up with diploids, down with triploids." Nice quote killperch.
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[hpb]

Many waters will not support natural reproduction and that's why they are stocked in the first place. I have read quite a few studies out here about much of what you are asking and the answer in short is that isn't isn't a pull the rabbit out of the hat deal- they have legitimate scientific date to back their decisions. Whether we as the public understand that or not. I relaize that they are providing something for the public and we do foot the bill for it but I don't think they have to explain every decision that they make in the newspaper, I don't want my money wasted that way. I would venture that all the reasons for the decisions are out there if you write or email the F and G and ask. I have many times and there has always been a response back to me.
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[windriver]

I may be mistaken but from what I understand the triploids do not spend their energy spawning and so put on weight faster then normal trout. I will ask BSflies about this but I believe one of the reasons that the brooks and hybrids in Henry's are growing so fast is because they are triploids and they do fight hard.

Windriver
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[bsflies]

I do not think that sterile fish fight less than fertile trout. Over the years of fishing and landing both, I believe that fish fight against pressure and that pressure on the line causes the fish to fight hard or less. Many times I have hooked fish, given them slack and they stop fighting and lay on the bottom of the lake.

This is why when fighting a large fish I try to give as little pressure as I can so that they will stop fighting the pressure. I do not believe that spawning makes fish more aggressive. Also last year on Henrys Lake the three year old triploid brook trout were about two inches longer and had a larger girth than did the diploids.

My experience with catching triploids has been that they break me off as quick or quicker than diploids - but of course I do not know which it was because they do not let me look at them up close and personal.

Keep the triploid program at Henrys Lake. Since they have been being planted there we have been catching more huge fish than we ever have before.

Good Luck - can hardly wait until June when I can wrestle with these hogs.

Bill
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[killperch]

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[windriver]

The Henry's Lake triploid program has been seriously in existence for about 4 years. It has only been the last two years that all hybrids are triploids and last year was the first year that all brook trout were triploids. So like you say the data is still coming in.

I think you are correct when you say that the Henry's Lake cutts do not get as big in other lakes. The cutts are all diploids and so the phenominal food base in Henry's does account for their larger growth.

The one thing that we are forgetting when we are talking about Henry's is that if we want the large hybrids and brooks, regardless of whether they are growing faster or slower then normal, then they have to be triploid if they are in a cutthroat watershed.

I for one like the diversity in multispecies fisheries including Henry's and if we do not want to invoke the wrath of the Endangered Species Act then we should keep stocking sterile brooks and hybrids in Henry's, Kokes in Ririe etc...

Good Fishing To You ALL
Windriver
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[hpb]

First- I don't know- so someone educate me- are there triploid cutts in Henrys? I don't think there are. Now there are cutts/bow cross- no rebreed, grow quickly because energy is diverted from egg production to growth- fish fight like maniacs because of the bow in them. You can't put bows in if you want to keep a pure strain of cutts and that goes for any lake that has tribs with cutt populations. Anywhere that you can bows breed with cutts you have to stop it. Look at the South Fork of the Snake. ( Bow elimination) If you don't then you have the Feds stepping in and telling you what you WILL be doing to protect the cutthroat, not what you Should be doing. There are a multitude of reasons for some of this and some are political and finacial.
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[killperch]

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[BrianID]

IMO triploids are a good thing for us fishermen. It is proven that triploids typically have slightly better growth rates. One reason that I have heard the F&G plant only triploids now is that it is easier to raise just one instead of two different rainbows. Having both triploids and diploids to managed for planting would take more planning in raising and planting than just raising triploids.
I could be wrong but I think the strain of rainbow is much more important than the Diploid/Triploid factor. Post up a link to those articles that say Triploids are less aggressive. From my experience the fight of a fish is strongly correlated with water temperature. I have notice that the recently planted diploid trout the F&G had donated by fish farms bite bait much better after they are planted than the Triploids the F&G plant. It may be the strain of rainbow or what they were feed before being planted.
Anyway, good post. You might be right that diploids could be better for us fishermen. If you have some more information about why diploids are more aggressive than triploids I would like to see it.

hpb,

None of the cutts the F&G plant are Triploids.
It may have not been the point that you were trying to get across but elimination of rainbows in the South Fork isn't a realistic goal. The F&G are just trying to reduce the number of rainbows. The F&G can't even eliminate rainbows from small reservoirs let alone a large river.
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[hpb]

Discussion is a good thing and this is a good topic for anglers to get their thought process going. I think that hatchery costs also play into the equation where there isn't enough resources to do everything and the most beneficial over all must be the course you take. I think a lot of lakes it would not matter if you planted non sterile fish because the lake does not have the habitat to have successful spawning anyway. The common thought is that bows are not native and shouldn't be able to spawn, cutts are native and they should be brought back everywhere within their native range. I personally do not buy into that thought wave because we as humans have destroyed much of their original habitat and to think that we can bring them back everywhere is foolish. Here is one example. The Bear river narrows below Oneida Res. The push is to bring back the native cutt and I know that the Feds and Pacific Power money have something to do with this thought wave. Sorry just not buying into that river ever being able to support a natural cutt spawn every again. A few years back it was an amazing bow and brown fishery and now it isn't. There are places that where the fish in the system that are doing well now are the fish that should be promoted and nutured. Those places are the ones that we screwed up as humans and we can't bring them back to their natural state. There are places that we should do everything that we can to preserve them or bring them back if it's possible but it's not every water. Humans aren't going away soon or reducing their numbers and we have to deal with it logically.
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[hpb]

Brian; but they are trying everything possible to eliminate them- high flows during their spawn, no limits- keep and kill. My real point though was just showing something where they do not want a breeding fish and why.
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[killperch]

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[killperch]

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[hpb]

[font "Helv"][size 2]http://fishandgame.idaho.gov/cms/fish/fishplan/BearRiver.pdf[/size][/font]
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[bsflies]

On this subject, I contacted personell of the Fish and Game Dept. They reported that an important concept is being left out of this discussion. That is that different systems often have very different results. What happens in one body of water may not happen in another body of water. After several studies of triploids, the performed well in some and poorly in others.

The growth of the triploids in Henrys might be the increased growth rate - or it may be that the triploids have a longer life, thus allowing them to live longer. In notes that I have taken after several interviews with F&G, it is hoped that the triploid brooks will have a longer life span in Henrys. Because triploids do not spawn and do not go through the stress of spawning, this may also increase this growth. There are studies planned that will examine the gonad (sex organ) developement on these fish in Henrys.

This has been a great discussion and an enlightning one. Thanks killperch for starting it.

Bill
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[BrianID]

I don't really have the time to look into the articles your talking about until next week. I will also try to find some other research done on triploids vs. diploids. I'll come back and comment if I find anything interesting.
By the way, good topic.
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[killperch]

Thanks for all the input. It is interesting to see how other fisherman feel. I deleted my posts due to an inenvertant attachment. Thanks everyone and try to read some of the research on the F&G website, very interesting.
killperch
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[BrianID]

[black]Here’s what I found after reading several research reports on the F&G website as well as some from a google search. [/black]
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[black]I still couldn’t find any reports with conclusive evidence showing diploids are more aggressive than triploids. At the moment I’m not convinced that diploids are more “hook friendly” than triploids. Diploids do seem to be more vulnerable to fishermen during the spring spawn. This may be a good thing or a bad thing depending on who you talk to. [/black]
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[black]I have read several studies that show different strains of rainbows are more aggressive. One thing that I do believe without question is that a hatchery rainbow trout planted when it is 10”-12” is more aggressive than a wild rainbow trout in similar conditions.[/black]
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[black]It would take some very solid data to convince me that diploid rainbows pull harder than triploids. Some of the hardest pulling rainbows that I have caught are triploids. I’ve caught triploids out of several places that pull just as hard as a smallmouth bass of similar size.[/black]
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[black]At Henry’s Lake I have noticed a big difference after the F&G started planting triploids. Some of the fishing techniques that worked well for me in the 90’s just haven’t worked very well the last few years. I don’t believe this change has to do with the diploid/triploid factor. I believe it has to do with less fishing pressure, less fish and more forage available per fish. [/black]
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[black]Below are some of my comments on the two studies I found most interesting. The results from these two studies contradict each other, which backs up what bsflies said "[font "Verdana"][size 2]What happens in one body of water may not happen in another body of water."[/size][/font][/black]
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[black]#1 In this report the fish were caught by gill net and electrofishing. It doesn't mention anything about rod and reel catch rates. Here’s some quotes from the report. [/black]
[black]“In both reservoirs, relative survival was significantly higher for triploid fish. The final catch proportions (triploid:diploid) were 1.4:1 in Treasureton and 1.9:1 in Daniels”[/black]
[black]“At age-1, mean length and weight values were similar for the triploid and diploid fish. During the second year, however, diploid growth was significantly higher than triploids. The trend reversed as the diploid fish reach sexual maturity. Age-3 and older triploids caught or exceeded diploid fish in length but not weight.”[/black]
[black]“Triploid rainbow trout demonstrated a benefit in relative survival, but no consistent growth advantage was found.”[/black]
[black][url "https://research.idfg.idaho.gov/Fisheries%20Research%20Reports/Volume%20130_Article%2008.pdf"]https://research.idfg.idaho.gov/Fisheries%20Research%20Reports/Volume%20130_Article%2008.pdf[/url][/black]
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[black]#2 This study showed a significantly higher (1:12) rod and reel catch rate for diploids in high mountain lakes around McCall. According to gill net samples, diploid survival was 4 times greater than that of triploids. The sample size for the 12 to 1 rod and reel catch ratio was only 13 fish. The small sample size makes the rod and reel catch ratio statistically inconclusive. Growth rates comparing triploids to diploids in these high mountain lakes showed no statistical difference. The only conclusive data this report showed was survival of diploids was better than triploids for these lakes during the years sampled.[/black]
[black][url "https://research.idfg.idaho.gov/Fisheries%20Research%20Reports/03-44%20Kozfkay%202002%20Hatchery%20Trout%20Eval.pdf"]https://research.idfg.idaho.gov/Fisheries%20Research%20Reports/03-44%20Kozfkay%202002%20Hatchery%20Trout%20Eval.pdf[/url][/black]

Anyway that is my 2 cents. Don't forget to post a link for the rest of us if you find interesting research on this subject.
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