Wild Rainbows

[drakeking412]

After a recent trip to Montana where rainbows are infested everywhere and spreading I have a question, why don't we have a stronger presence of wild rainbows in our state? I know of a few streams where they naturally reproduce but they're few and far between and the relative fish size is usually small. With all our rainbow stocking in state why haven't we seen more wild rainbows? Do the browns really just out compete them entirely and is that couple degrees of hardiness the browns hold the upper edge? I'm not really a rainbow guy myself but I do like a clean white tipped rainbow from time to time.

 

[lycoflyfisher]

Well they are a non native species to Pennsylvania, so many anglers would rather not see reproducing populations spread throughout the commonwealth.

Depending on the genetic stock the fish are from, there are challenges with the timing of their spawn. If they do indeed spawn in the spring, the highly variable flows we typically experience March - May is not conducive to rainbow trout reproduction.

 

[Out4Trout]

I wonder the same thing. I spent 15+ years in Colorado and there were many places to catch wild rainbows. As far as the high water in spring in PA, you should experience the runoff out west, puts our little high water issues to shame and the wild rainbows manage to make it through just fine. I have also fished many streams in Colorado with a good population of wild browns and wild rainbows, I will admit the rainbows were less common but did exist in the same waters just different holding locations.

 

[jifigz]

I think wild rainbows are more common and widespread in PA than many believe. I also feel, from reading numerous sources for many years, that rainbows can tolerate the same temperature browns can for the most part. I have turned up wild rainbows in quite a few streams in my area. I couldn't care less if wild rainbows get well established and thrive. Brook trout are never coming back to our bigger streams like Penns and the Little J, browns are already thriving and invasive and non-native, so what would it hurt to have wild rainbows as well? As long as they don't colonized our mountain headwaters and push the brookies out then who cares?

I do think they exist more than people give them credit for and the dominance of browns probably keeps them from truly taking over a stream....or most streams, at least.

 

[JeffK]

Over in NJ, studies a long time ago showed the sudden drop in pH from snow melt was an issue. Out East snow is frozen acid rain and there is an acid pulse when rainbow fry are vulnerable; the fall spawning browns and brookies are more developed in the spring and can tolerate the pulse better. (at the time air coming from the West into NJ didn't meet clean air specs so NJ had no shot at meeting reqts) The NJ wild rainbow streams have an outflow from a lake that buffers the pulse or some limestone influence. However, more people are seeing wild rainbows now. Maybe the snow free winters of late have lessened he acid pulse?

Another hypothesis was that some streams got rainbows earlier that were directly related to their wild ancestors in CA. For a 100 years or more stocked rainbows are more like domestic animals bred to be raised in a hatchery. (read An Entirely Synthetic Fish). Even one generation in a hatchery lowers wild characteristics and lessens breeding success in the stream. The first fertilized eggs though came right from CA and were closer to the wild strain. The Delaware River wild rainbows mythology has the early CA rainbows as their source when an Erie RR locomotive broke down and Dan Cahill tossed the fertilized rainbow eggs into the Delaware rather than letting them perish. However, since records back then were poor research in the matter is tough.

 

[PennKev]

Out4Trout wrote:
I wonder the same thing. I spent 15+ years in Colorado and there were many places to catch wild rainbows. As far as the high water in spring in PA, you should experience the runoff out west, puts our little high water issues to shame and the wild rainbows manage to make it through just fine. I have also fished many streams in Colorado with a good population of wild browns and wild rainbows, I will admit the rainbows were less common but did exist in the same waters just different holding locations.

This is very true, however the timing of runoff in the west can be months later than our spring high water events. The timing of the high water in our streams may not be suitable for very successfull spawns, even though it is not as severe as what is common on western rivers and streams.

The acid rain/snow theory posted here may have some merit also. Water chemistry cannot be overlooked entirely and if chemistry is particularly bad for spawning success at the very time the spawn is occurring, I could see it being a problem.

I also agree that wild rainbows are more wide spread than what is generally thought. However, robust populations are very uncommon compared to browns and brookies.

Wild ainbows are much more common as you go south along the Appalachians, , having displaced brookies in many areas. I think it would be interesting to compare spring flows, temps, and water chemistry in some of those streams with what we have in PA and see what is different and what correlations there are with strong rainbow populations.

 

[silverfox]

jifigz wrote:
I think wild rainbows are more common and widespread in PA than many believe. I also feel, from reading numerous sources for many years, that rainbows can tolerate the same temperature browns can for the most part. I have turned up wild rainbows in quite a few streams in my area. I couldn't care less if wild rainbows get well established and thrive. Brook trout are never coming back to our bigger streams like Penns and the Little J, browns are already thriving and invasive and non-native, so what would it hurt to have wild rainbows as well? As long as they don't colonized our mountain headwaters and push the brookies out then who cares?

I do think they exist more than people give them credit for and the dominance of browns probably keeps them from truly taking over a stream....or most streams, at least.

I think a lot of people care. That's the attitude that has gotten us to where we are. People have spread non-native species all over the world, and now we're dealing with the consequences. Non-natives have an impact beyond trout. When you disrupt the natural balance of an ecosystem, there can be widespread consequences.

I'm personally happy that rainbows haven't become more established in the wild here and I hope it stays that way.

 

[Mike]

RT are almost exclusively fall spawners in Pa. Winter water temps are too cold for most RT eggs or fry to survive. Exceptions where populations have been produced are some limestoners where water temps do not drop to critical levels in winter and a few western Pa freestoners that were stocked with spring spawning RT in the 1930’s.

 

[troutbert]

In those western freestoners the rainbows do compete with the brook trout.

If those rainbows were more widely distributed in freestone streams in PA, the brookie populations would suffer.

The reason there are not more rainbows in PA has to do with the genetics of the rainbow strains.

Not acid rain and snow or runoff or anything else.

There has been an expansion of wild rainbow trout in limestone streams in PA in recent years, because of stockings of rainbows by fee fishing operations. They don't get their rainbows from the PFBC, they get them from other sources, so the genetics are different.

 

[jifigz]

silverfox wrote:

jifigz wrote:
I think wild rainbows are more common and widespread in PA than many believe. I also feel, from reading numerous sources for many years, that rainbows can tolerate the same temperature browns can for the most part. I have turned up wild rainbows in quite a few streams in my area. I couldn't care less if wild rainbows get well established and thrive. Brook trout are never coming back to our bigger streams like Penns and the Little J, browns are already thriving and invasive and non-native, so what would it hurt to have wild rainbows as well? As long as they don't colonized our mountain headwaters and push the brookies out then who cares?

I do think they exist more than people give them credit for and the dominance of browns probably keeps them from truly taking over a stream....or most streams, at least.

I think a lot of people care. That's the attitude that has gotten us to where we are. People have spread non-native species all over the world, and now we're dealing with the consequences. Non-natives have an impact beyond trout. When you disrupt the natural balance of an ecosystem, there can be widespread consequences.

I'm personally happy that rainbows haven't become more established in the wild here and I hope it stays that way.

So, to directly reference my first post, if browns are already established and clearly control the waters, why would you care if rainbows started to occupy some of the space the other invasive species already controls? I said as long as rainbows don't push out brookies in their streams.

I am all for limiting and stoping invasive species where possible.

 

[Swattie87]

troutbert wrote:

There has been an expansion of wild rainbow trout in limestone streams in PA in recent years, because of stockings of rainbows by fee fishing operations. They don't get their rainbows from the PFBC, they get them from other sources, so the genetics are different.

There are Rainbows, capable of reproducing and well established in PA freestone systems too. The one in particular in western PA is well known. Fortunately they haven't really spread beyond that one watershed, though they have big river access and in theory could. FWIW, I much prefer the Browns in that watershed...

I stumbled on another in NC PA that was quite concerning, given its location. A private "pay to fish" operation has stocked a certain strain of Rainbows that are clearly capable of reproducing, and are seemingly doing it quite well. I've still caught more wild Browns and Brookies, but I've caught many dink, fully wild looking Rainbows, well above the private water on public land, along with several legal sized wild looking Rainbows. I find it unlikely the pay to fish outfit is stocking them that small, or that far upstream. They're in a watershed with a lot of prized Brookie strongholds. I struggle to understand why this is allowed to happen. The outfit even advertises that they do this. The stream is listed as an unstocked, Class A Brook/Brown mix. Last time I was there was in season, so I creeled the two legal sized Rainbows I caught and gave them the old lemon/butter/onion treatment. I can't say I've caught wild Rainbows elsewhere in this watershed, but I can verify the ones I caught in this one stream can swim, and came equipped with fins.

Wild Rainbows in PA, while a novelty, are not a good thing.

 

[Prospector]

Here is an old thread where Mike explains why there are few PA streams with Wild Rainbows. Consistency in water temp ranges. I was getting a broken link when I tried to insert the whole thread. So here is Mike’s post

It’s one of my alltime favorite posts since it explains the question we all ask. With all the rainbows being stocked in PA, why so few wild rainbow when there are so many streams with wild brook and brown trout.

Mike...3-21-2014.....
The subjects of limited RT reproduction in Pa and temperature sensitivity come up periodically here. Yesterday, I happened to be doing some research and stumbled across two scientific publications that refreshed my memory. Here is the long and short of it:

Primary limits on reproduction: Water temps that are too warm (higher than 56 deg F) or too cold (42 deg F or lower) limit or prevent reproductive success, despite the fact that RT adults survive quite well at higher temps. These temps that affect reproductive success fall well within the range of typical Pa freestone temps, but not limestoner temps near their source. Eggs will not develop normally in the fish if constant water temps of 56 deg F or higher are encountered. Temps not exceeding 54 deg F are preferable for a period of at least 6 months prior to spawning. How many streams in Pa do not exceed 54 deg F during the summer? Likewise, excessive losses of eggs occur during incubation in the redds if temps fall below 42 deg F. Think about Pa winters, which explains why fall spawning of Pa rainbows is not a good strategy.

This does not necessarily explain two streams in the Allegheny drainage, but to my knowledge those are the only two freestone exceptions with substantial multiple year classes of fish that have been found in Pa. and I don't have enough knowledge of those to express an opinion as to the local effects that allow them to be exceptions. Additionally, I don't know whether or not they still support wild RT pops. I think, however, that the first paragraph above provides good guidance with respect to what the problem probably is with RT reproduction in Pa.

Warm RT fisheries: As for adult RT survival and fishing, one study of a formerly very successful fishery in which water temps over the years gradually increased due to urbanization revealed that water temps that exceeded 68 deg F resulted in substantially more mortality than did the C&R fishing that was occurring over those fish during those warmer water temp periods. The fishery declined. So water temperatures alone, just like the ones we see annually below Blue Marsh Dam during the summer in the Tully DH Area, were enough to cause considerable mortality.

 

[salmonoid]

Figured this wouldn't be a legitimate thread without a photo of a fish of the titlesake to enter in the stocked vs. wild debate.

I caught this opening day this year from an ATW in York County. A few rainbows do hold over into the fall most years, although they look pretty spindly. The stream also has a pretty good head of wild brown trout in it.

The next stream south from this has also produced rainbows, but nothing colorful or in good enough fin quality to warrant anything but a stocked look from me. That stream is not stocked but I suspect the fish escape to it from the big river when it gets too warm.

 

[MarkC]

Callicoon creek (an upper Delaware trib) is an unspectacular freestone stream: high and turbid and flood prone in the spring, just about dry and hot in the summer, yet it is obviously a spawning trib for the Delaware rainbows. It holds baby rainbows until it is too warm then I assume they go down to the main river; you can often find pods of 50 or more silver bullets rising on the lower river when the tribs dry up.

Perhaps they can spawn in a less than ideal tributary if they have a big, stable river to drop back to.

Mark C

 

[Wild_Trouter]

Wild Rainbows are actually more common than most think. There are several streams in SC/NC PA that I fish and it is very cyclical for the reasons already cited. When things come together, you may have a small population of fish for a year or two (maybe three in some cases) and then they disappear for a time. At some point the cycle begins again, but in these particular streams, there is never a constant population. I shared some of my findings with Jason Detar of the PFBC. Some of the streams are limestone and there is one that is completely freestone. I love all wild trout, but largely agree that I would not want to see them colonize a stream that already had a viable (or capable of producing) wild brook trout fishery since we have lost so many wild brook trout streams already. For streams not suitable for brook trout for whatever reason, I'm in favor of letting Mother Nature decide whether rainbows or browns rule the day.

 

[marcq]

I’ve only caught them in limestone creeks. Big spring being the best I’ve fished but I’ve also caught a hand full of tiny rainbows in the little Lehigh that had to be wild. Wild rainbows are awesome. I wish more streams had them.

 

[moon1284]

I'm not real crazy about wild rainbows. We have a ton of them in WNY. They have a short lifespan and don't get much bigger than 12-inches, upper delaware aside.

Wild rainbow populations that connect to large lakes (erie, Ontario, or finger lakes) are cool.

 

[marcq]

These are the kind I like targeting. Limestone creeks using sculpin patterns.

 

[moon1284]

Yup those are awesome

 

[silverfox]

jifigz wrote:

So, to directly reference my first post, if browns are already established and clearly control the waters, why would you care if rainbows started to occupy some of the space the other invasive species already controls? I said as long as rainbows don't push out brookies in their streams.

I am all for limiting and stoping invasive species where possible.

jifigz wrote:

I am all for limiting and stoping invasive species where possible.

So why promote increasing the presence of another non-native species?

Compounding a problem doesn't seem like a sound argument to me.

Of course, I'm an extremist. I'd rather a river be native, even if that means there are no trout than it be artificially maintained as a non-native trout fishery. You mentioned brook trout never "coming back" to Penns. You do know that they are in Penns and have been forever right? I don't know for certain whether they're residents or if they only use it for migration, but I've caught them in the mainstem.

I'm not trying to push my beliefs on everyone, just pointing out that there are people out there who take a hard line on the non-natives. I'd personally dump the rotenone in the Letort if I could, but I'll fish for the euro fish while they're there. I do find it interesting how accepting PA is of non-native species while states out west take the opposite approach.

Timely point of reference: https://k2radio.com/yellowstone-to-biologists-eliminate-non-native-brook-rainbow-trout-in-gibbon-river/