Why Not Stock Only Rainbows?

[Sylvaneous]

Are there any good reasons why not to stock only rainbows? I had heard they like to move more than browns, but really, do we have much more besides anecdotal evidence and isn't it different on some streams? My main stocked water is Oil Creek, which, like most all our stocked waters, only just gets too warm most summers. If Oil Creek (and many others) waters never got over, say, 78, it would hold on to its rainbows. Browns are done by that point. This year, I have caught rainbows almost exclusively there. If rainbows are, indeed "chickens with fins" why wouldn't Oil creek or Penns, that has wild brown and brookies within their watersheds be stocked, where they are, with only rainbows?

Syl

 

[redietz]

Browns are much more heat tolerant than rainbows, and in my experience adapt to stream conditions vs hatchery conditions more readily.

Then there's the fact that some of us plain don't like stocked rainbows and would take up bass fishing if they were the only choice.

 

[dryflyguy]

I'd also agree that browns seem to tolerant adverse conditions well.
I know quite a few streams with lots of wild brownies, that regularly get into the '80's over the summer. I don't bother them then.
But when I go back on the fall - and water temps have cooled - they're back. They find somewhere to weather the heat.

Just check the WT stream listings for the state. There are a lot more streams that hold wild browns, than wild rainbows.

 

[Dave_W]

Sylvaneous wrote:
Are there any good reasons why not to stock only rainbows?
Syl

I've always assumed that 'bows were a bit cheaper and perhaps grew a bit faster. Contract hatcheries seem to raise mostly 'bows too. In fact, if you look at the PFBC's stocking info, they do in fact stock a great majority of rainbows. My guess would be that the only reason they still stock browns and brooks is mainly a matter of social policy and tradition. Perhaps in the case of STs, acidic streams may have something to do with it too.

Personally, I'd like to see the agency stick with all the species and also believe that browns are better suited to most special reg waters, esp if there is little or no natural repro.

If it is a matter of not mixing stocked fish with wild, then perhaps a case can be made for 'bows only and this is done in some waters. Honestly, however, I don't think the PFBC believes the average, traditional angler in PA is going to care much that he is catching stocked BTs in a stream with wild BTs, or whether they would even know the difference.

 

[Mike]

I am not addressing the question, only one comment about which species "run." It is the BT and ST that run; the RT are significantly less likely to run. Yes, the study was done on Pa fish as part of the larger trout residency study.

 

[jifigz]

It certainly wouldn't bother me if the commission only stocked bows, but there are a few instances when I think that it should also still produce and stock a very small number of browns and brooks.

Personally I don't think that any water with a wild population of any of the three species of trout that ranks as Class B or better should receive any stocking. Secondly, I think that streams that have the potential to support a wild population should be stocked with either Browns or Brooks as they seem more likely to take hold in our waters than do rainbows. I have heard before that stocking to establish wild populations isn't the aim of the commission and yada yada yada. Whatever, I don't see why that isn't the aim of trout stocking within the commonwealth. Where does everyone think our wild brown populations got their start anyway? I say stock streams and once a significant wild population has begun to take hold, stop stocking. I know many across the state, but probably not this forum, will disagree with me, however.

 

[pcray1231]

They came from stockies, but back in the 20s and 30s, when hatcheries were a fairly new thing. Over the many generations of growing fish in a hatchery setting, they have unnaturally selected for genetic traits which are deemed good for growing a fish in a hatchery. Unfortunately, these traits are the exact opposite of what leads to success in the wild. Heck, the rainbows even breed at the wrong time of year!

Stockies certainly try to breed. But their success rate is low. If they do reproduce, their offspring are also less likely to breed successfully. It'll take a number of generations before any descendents are approaching the viability of wild stock.

Further, virtually every watershed has wild browns and brookies somewhere. Just like stocked fish, wild fish travel.

Meaning, if the stream is becoming favorable for natural reproduction, there is typically wild seed stock available, and if anything, you don't want stockies competing in stream with those fish, or worse, breeding with them and contributing inferior DNA to the next generation. And that's why, in some cases, the PFBC avoids stocking a species when the same species is present wild in the stream. It's also one reason to favor rainbows, as there's less chance of contaminating a budding or existing population.

In rare cases where the stream is capable but there's no feedstock, such as above a waterfall or physical barrier, you'd be better off transplanting wild stock from elsewhere.

 

[bigjohn58]

Fishing Creek in the Mill Hall area is mostly only stocked with rainbows with the occasional brookie. This way they don't really interfere with the wild browns especially since it is kind of a larger trout stream. To me it works pretty well and the rainbows have little issue holding over. The brookies on the other hand are often dumb and caught out in very short order by the countless meat hunters that frequent that stream.

 

[jifigz]

pcray1231 wrote:
They came from stockies, but back in the 20s and 30s, when hatcheries were a fairly new thing. Over the many generations of growing fish in a hatchery setting, they have unnaturally selected for genetic traits which are deemed good for growing a fish in a hatchery. Unfortunately, these traits are the exact opposite of what leads to success in the wild. Heck, the rainbows even breed at the wrong time of year!

Stockies certainly try to breed. But their success rate is low. If they do reproduce, their offspring are also less likely to breed successfully. It'll take a number of generations before any descendents are approaching the viability of wild stock.

Further, virtually every watershed has wild browns and brookies somewhere. Just like stocked fish, wild fish travel.

Meaning, if the stream is becoming favorable for natural reproduction, there is typically wild seed stock available, and if anything, you don't want stockies competing in stream with those fish, or worse, breeding with them and contributing inferior DNA to the next generation. And that's why, in some cases, the PFBC avoids stocking a species when the same species is present wild in the stream. It's also one reason to favor rainbows, as there's less chance of contaminating a budding or existing population.

In rare cases where the stream is capable but there's no feedstock, such as above a waterfall or physical barrier, you'd be better off transplanting wild stock from elsewhere.

A good argument, but how can you prove that nearly every wild brown trout stream was colonized with fish from stockings from the 20's and 30's? I am not disagreeing with you, but I would certainly bet that our modern modified browns have been the root of some established populations. Also, if a more "wild" brown trout was once in a hatchery setting that was the root of our many wild BT populations, then they could certainly once again take fish and genetic material from a wild population here in PA and have more adaptable fish to once again stock. I think that most serious anglers who love and care for fish and water could quickly identify a stream as to having potential to have wild fish in it after determining a few small details about the water. I've found wild browns, and fantastic numbers and size to my surprise, in streams that in no way ever appeared to be trout water. Brown Trout are a very successful invasive species. As Jeff Goldbloom said in Jurassic Park, "life will find a way," and I think that he is right.

I do think though that as soon as a decent population of wild browns has been discovered trout stocking should halt immediately of any fish. From there monitor the population and see what happens. Without a decrease in water quality and habitat, I would bet that in nearly 100% of the time the population would thrive after the cessation of stocking.

 

[jifigz]

Out of curiosity, is there a list of stockings within the state that go back to the 20's and 30's?

 

[troutbert]

Do you know of any streams that have the conditions to support wild trout, but that have no wild trout?

 

[Sylvaneous]

dryflyguy wrote:

Just check the WT stream listings for the state. There are a lot more streams that hold wild browns, than wild rainbows.

That has more to do with reproduction. Rainbow stockies are screwed up because they are spring spawners unlike browns and brookies. Something about the reproduction timing of stocked rainbows prevents them from reproducing. In the south, they are a menace to wild brookies because, for some reason (historical biologist needed here, if there IS such a thing) the fish they stocked at some point weren't all screwed up.

 

[Sylvaneous]

jifigz wrote:
Personally I don't think that any water with a wild population of any of the three species of trout that ranks as Class B or better should receive any stocking. Secondly, I think that streams that have the potential to support a wild population should be stocked with either Browns or Brooks as they seem more likely to take hold in our waters than do rainbows. .

I mentioned this in case there actually is some issue with stocked fish living to reproduce with wild fish in the watershed and... I'm not a fish biologist... some genetic problems like weakening the stock or spawning to produce less viable offspring.

Is that a real thing? If not, in my mind, there wouldn't be an issue with stocking browns on that level.

syl

 

[jifigz]

troutbert wrote:
Do you know of any streams that have the conditions to support wild trout, but that have no wild trout?

In my county I do not know of any streams with habitat and conditions to support wild trout that do not have wild trout. I am obviously not aware of all streams within the state. I am sure there are streams that have beautiful water and no wild trout due to human interfernce that has degraded water quality and or habitat.

What is your point, though, troutbert? As far as my opinion stated means that all of these streams should receive no stocking. I think that they would all benefit greatly from it.

 

[jifigz]

Sylvaneous,

I am well aware of the success that Rainbows have had in the southern Appalachian streams. If this was a result of "non-screwed up" fish stocks being planted there, then how did our few Class A rainbow trout streams get started? Did we get only a handful of "non-screwed up" fish stocked only in the northwestern corner of our state? And why are the rainbows "screwed up?" They are a naturally spring spawning fish and maybe just don't quite do as well here in our streams. And maybe healthy established populations of wild browns further hinder their spawning succcess. I do, however, believe that there are more wild rainbows spread across our state than many people believe. They are obviously overshadowed by the more abundant wild browns, but I think that they are there.

I am also sure that some browns hold over and successfullly contribute their genes to the stock of wild browns in a stream. I think that it is silly to assume that this never happens.

 

[troutbert]

jifigz wrote:

troutbert wrote:
Do you know of any streams that have the conditions to support wild trout, but that have no wild trout?

In my county I do not know of any streams with habitat and conditions to support wild trout that do not have wild trout. I am obviously not aware of all streams within the state.

What is your point, though, troutbert?

You proposed stocking trout in order to establish wild trout populations.

To do that, you would have to find a stream with the right conditions to support wild trout, but that has no wild trout presently.

You said you don't know of any streams like that. I don't either.

I'm skeptical that there is any significant stream mileage in PA that has the right conditions for wild trout, that does not already have wild trout.

 

[ryansheehan]

From what I understand rainbows spawn in the spring in the northern hemisphere and the fall in the southern.

 

[moon1284]

The book an entirely synthetic.fish (or something close to that) is relevant to posts like this.

The stocked fish today are nothing like the stocked fish of 100 years ago.

 

[pcray1231]

Jif, there are indeed stocking records going back that far. But perhaps less detailed. The fish commission had a train car and carried mostly fingerlings/fry, as adult stock of the day were too hard to raise (more wild, would ram into concrete raceways, fight in crowded environments, run from humans there to feed them).

Often they'd just give out fry to locals to stock where they wished.

The genetic origin of stocked strains that could be raised to adulthood was mostly carried out in the Midwest through mixing of various strains and selective breeding. Selective breeding can drastically change traits in a short period of time. Look at dog breeds. A Chihuahua and great Dane are the same species of animal!

 

[fayettenamese]

I know of a few streams that could support wild trout but do not. Physical barriers close to the mouth are the culprit. Between the waterfalls and the mouth, wild trout exist yearlong. There are miles of habitat above the falls on each of the streams. In time, nature will take care of this and move some fertilized eggs above the falls, but that may take a few centuries.

I am sure that there were historical populations of wild fish above the falls on the streams I am referring to, but man degraded the water, kiiled the fish, and they have recently started to repopulate upward from the mouth.