Nice Triploids!

[Mike]

Got to see the Triploid RT from Tylersville State Fish Hatchery the other day as they were being stocked in some sections of Jordan Ck, Lehigh Co. I think the average size trout were the nicest average size trout that I have ever seen stocked preseason. Variability in size was very low, which was important in formulating my opinion. Most seemed to be 10.5-12 inches and plump.

 

[Dave_W]

Mike,
I'm sure I'm not the only reader who is in need of some basic background info on this matter. I have read about triploids in other state's and programs and I know a bit about them, but was unaware that PFBC was stocking them in PA.
Anyway, what are the short answers to the following:

1. What is a "triploid" and what advantage does raising them provide?
2. How widespread is this in PA and when did it start?
3. With respect to size or other issues, what can anglers expect to be different with triploids?
4. Is this done for STs and BTs? Other fish species?

 

[outsider]

Never heard the term before. Thought they might be 3 headed fish which would give you 3:1 odds to catch one.

 

[ryansheehan]

Dave_W wrote:
Mike,
I'm sure I'm not the only reader who is in need of some basic background info on this matter. I have read about triploids in other state's and programs and I know a bit about them, but was unaware that PFBC was stocking them in PA.
Anyway, what are the short answers to the following:

1. What is a "triploid" and what advantage does raising them provide?
2. How widespread is this in PA and when did it start?
3. With respect to size or other issues, what can anglers expect to be different with triploids?
4. Is this done for STs and BTs? Other fish species?

It means they're sterile. Can't speak to the other questions but you can draw your own conclusions.

 

[sandfly]

1- triploid is a rainbow genetically change to be more aggressive and grow faster.
2--not very mostly in the southeast and south west counties with lakes
3- fighting ability, firmer meat.
4 No can only be done with rainbows

 

[Dave_W]

outsider wrote:
Never heard the term before. Thought they might be 3 headed fish which would give you 3:1 odds to catch one.

Now this is what we need - three times as easy to catch, er, "utilize" that is. int:


Yes, Ryan is correct - they're sterile and, it has been my understanding that this fact means they grow a lot faster since their metabolism does not get focused on reproductive growth. There was a controversy some years ago about triploid rainbows out West that were coming from the same lake and were world records and whether they qualified for such status. Sometimes they're called "frankenfish" and other terms.

I don't really have an opinion on 'em one way or another, but am interested in learning more about their use in PA.

 

[ryansheehan]

sandfly wrote:
1- triploid is a rainbow genetically change to be more aggressive and grow faster.
2--not very mostly in the southeast and south west counties with lakes
3- fighting ability, firmer meat.
4 No can only be done with rainbows

From what I understand they are not genetically modified. It's just 3 sets of chromosomes instead of 2. I read a little piece about them on the web a little while ago will find and post.

 

[ryansheehan]

Here

 

[PALongbow]

I would like to see stocked trout that are harder to catch. a lot less of them would end up in freezers....

Ron

 

[FarmerDave]

sandfly wrote:
1- triploid is a rainbow genetically change to be more aggressive and grow faster.
2--not very mostly in the southeast and south west counties with lakes
3- fighting ability, firmer meat.
4 No can only be done with rainbows

Your number 4 is only have right. It hasn't happened in PA, but it can be done.

Triploid simply means three sets of chromosomes rather than 2, resulting in a sterile fish.

In a nut shell... By applying pressure to the fertilized egg at the right time (s), the egg retains the third set and developes into a sterile fish. Not a hybrid, just sterile. It isn't all that difficult, and I'd imagine that it can be done with just about any fish. Can and apparently has happen naturally with rainbow trout.

The white amurs I purchased for my pond were sterile triploid. Way cheaper than surgical neutering. ;-)

Triploid brook trout have also been produced, and studied for possibly stocking in western mountain lakes instead of diploid brook trout which are displacing native trout. I don't know all the details.

Seedless watermelon are also triploid.;-)

Edit: I posted that before Ryan posted a link to much of that info. But I didn't delete my post because I know it can and has been done with brook trout as well.

 

[Zak]

Interesting.....I like bigger fish but I'll miss my holdovers if they end up being easier to catch. My guess is they will act just like every other pressured trout and get a little finicky.

 

[JimKennedy]

Back in the 1970s, grass carp and bighead carp were billed as triploid and sterile. They were stocked to control out of control water grasses. Evidently triploid does not equal 100 percent sterile, as evidenced by the proliferation of these beasts.

 

[KenU]

Naturally reproducing rainbows have displaced native brook trout all thru southern Appalachian streams. So far they have only been able to establish populations in a few PA streams. I would like to see triploid rainbows stocked anywhere they could threaten native brook trout. As far as I know rainbows do not displace brown trout. In addition, stocking only rainbows would make it a lot easier to distinguish between stocked and wild trout during surveys. This would also make it much easier for anglers to distinguish between wild and stocked trout: a question frequently raised on this site.

 

[OldLefty]

Actually, a prolific rainbow population can have a severely limiting effect on browns. I know that, when I fished southwestern Va. a lot back in the day I had conversations with some biologists about this. There was an effort to try to address this by stocking the daylights out of a stream with brown trout fingerlings. This stream had a sparse population of wild browns but the rainbows kept the brown trout numbers down.

 

[KenU]

All the more reason to stock triploids. It is well known that rainbows haven't been able to establish populations in PA streams, but they have displaced brook trout in the southern Appalachians, so there is the possibility that could happen here as well.

 

[FarmerDave]

JimKennedy wrote:
Back in the 1970s, grass carp and bighead carp were billed as triploid and sterile. They were stocked to control out of control water grasses. Evidently triploid does not equal 100 percent sterile, as evidenced by the proliferation of these beasts.

I don't think they were "billed" as triploid until about the mid 80s.

The problems are:

1. Grass carp were first introduced in the US in 1963. Producing triploid versions were not developed until about 20 years later. It was believed that grass carp "rarely" reproduced outside their native range. This might be true, but unfortunately "rarely" does not equal never. Most states prohibited it, but the problem is, "most does not equal all.

2. I think for a time, some were sold as surgically sterilized. But there is a problem with that, too. A study was done in 1983 (masters thesis by someone at UCF) where several grass carp (juvenile and adult) were surgically sterilized. After 6 months, 59% of them regenerated the tissue and were able to reproduce and each female could product 20K eggs.

3. Techniques for easily making triploid grass carp were developed (in 1984?) are not 100% effective, meaning that some that were supposed to be triploid were likely not. So, each one has to be tested. But are they? They likely are now, but damage was done.

etc etc

I am not a biologist.

 

[geebee]

FarmerDave wrote:

sandfly wrote:
1- triploid is a rainbow genetically change to be more aggressive and grow faster.
2--not very mostly in the southeast and south west counties with lakes
3- fighting ability, firmer meat.
4 No can only be done with rainbows

Your number 4 is only have right. It hasn't happened in PA, but it can be done.

Triploid simply means three sets of chromosomes rather than 2, resulting in a sterile fish.

.

the majority of stocked trout in Europe are triploid - brown, bow or blue. they also in one or two places create triploid atlantic salmon where the wild Salmon runs have disappeared due to lack of spawning habitat ( due to dams largely).

they do grow quicker and are usually used in small commercial ( pay as you go) Stillwater fisheries, to supplement the natural stocks on large reservoirs, or on places like the Test and the Itchen, where they introduce 'pellet pigs' on some of the more expensive beats of a size that the natural river could not produce, typically fish of 3-5lbs suitable for the hero shots, which are then killed after a short time in the river and replaced with more fish.

thankfully, some beats are changing back to wild fish only due to customer preference.

I've caught hundreds of Stillwater triploids in the UK and Ireland myself, my opinion is that they don't fight as well as wild fish or holdovers here in PA.

in the size that Mike mentioned I see no issues, that's the size many UK reservoirs stock at, and they fight quite hard, especially in cooler weather, but in the aforementioned pellet pigs sizes of 5lbs+ they fight like wet slugs.

A question of fat vs muscle i think. i will be interesting to see how well river triploid bows are received by the fisherman in PA.

 

[krayfish2]

Is this one of those beautiful triploids you speak of? Absolutely stunning markings on the fish. I also love how the anal fin touches the tail. You don't get to see that very often. Too bad they're sterile because I'd sure like to see genetics like this mixed in with the existing wild fish population. Reminds me of something you'd see from Montana. LMAO

I almost forgot to ask the most important question.....
Wild or Stocked?

 

[salmonoid]

krayfish2 wrote:
Is this one of those beautiful triploids you speak of? Absolutely stunning markings on the fish. I also love how the anal fin touches the tail. You don't get to see that very often. Too bad they're sterile because I'd sure like to see genetics like this mixed in with the existing wild fish population. Reminds me of something you'd see from Montana. LMAO

I almost forgot to ask the most important question.....
Wild or Stocked?

Next time, could you make sure you wet your hands and not lay it in the dirt? It wipes the slime off of them, and they are more susceptible to disease. A good triploid is too valuable to be utilized only once..

 

[Chaz]

Large numbers of stocked rainbows will always degrade a brook trout fishery, they will take the best lies in stream and because they are very aggressive feeders they grow faster than brookies. If trout are continually stocked the brookies are stunted and will disappear from the more desirable stream sections.
2 of my favorite brookie streams have met this fate.