Ditch at Big Spring Creek, Cumberland County Pa

[albud1962]

All the aquatic vegetation at the ditch is gone. Not sure what happened there, it was pretty thick back in July. The bottom is pretty barren and the trout are exposed to avian predators. A heron was circling as I took pictures. Anyone have ideas what happened here?

 

[JackM]

Could be a completely natural phenomenon.

 

[Dave_W]

Beats me. The ditch water level was temporarily dropped a bit recently for survey reasons but this should not have had any impact on aquatic vegetation.

Broadly and relatively speaking, water levels and vegetation densities across the CV streams have really been up and down in the last year. Some of this is just natural and a drop down of weeds can have positive impact by clearing sediment. I think lower flowing aquifers from last year's weather patterns may have played some role.

I don't think we're seeing some sort of major change in vegetation across the CV streams. Generally speaking, the CV streams, and the ditch in particular, seemed to me to have a good bit less weeds back in the 1980s than they do today. But we shouldn't be surprised to see some fluctuation.

 

[albud1962]

Dave
It was only at the ditch. Below the bridge things looked great.

 

[troutbert]

It could have been caused by an herbicide.

Herbicides are very widely used. And there are many ways they can get into the water.

 

[redietz]

Could it have been deliberate? I've long thought that the filimentous algae in the Ditch was just locking up the nitrogen left over from the hatchery and preventing the growth of more typical spring creek flora like water cress, watercrowfoot and elodea.

I do know that since they finished the bridge repair, I've seen fewer and fewer fish in the ditch, and earlier this year it looked like there was no suitable spawning area in it at all.

I could be way off base, but if this is one time shot, I'm viewing it as a positive.

 

[nymphingmaniac]

FWIW I was talking along Spring creek this weekend near Benner Springs and I commented that the amount of vegetation was surprisingly low. Historic lows. If there is a connection, IDK

 

[Chaz]

They really should restore the flow of the creek by removing the dam at the end of the ditch. All it does is block fish movement and create a fake stream environment. I realize that I may be the only person in the universe that feels this way, but it's so un-natural I can't stand the way it looks.
As for spawning habitat it'll be just fine.
I looked at the flows and the only time there is an obvious change in flows was on August 17, probably the day they did the survey. That doesn't rule out another impact, it's just the most obvious.

 

[LetortAngler]

I like the dam for one reason. It gives the ditch DEPTH which gives the trout security, and it is pretty much already at the immediate headwater. Maybe the spawn is better with the dam.?
It is after-all the last remaining spring creek that has a class A pop of brookies in the state.
I would hate to jeopardize that over a small dam removal.

I was there last weekend, and the ditch still has no aquatic veg, other than one big bed of elodea a few feat down from the hill side where it emerges.

 

[albud1962]

I noticed a similar phenomenon at the Rock on Spring Creek, The conditions exactly the same.

I had some video of the ditch last year at this time and there was ample vegetation. My recollection was last year's summer was harsher than this year. Still a mystery

 

[troutbert]

I recently walked along Spring Creek downstream from the Benner Springs hatchery. There was plenty of aquatic vegetation on the streambed. I'm not sure what it's called. Maybe elodea?

 

[SteveG]

I'd also love to see the dam at the ditch gone. It makes it too artificial, and who knows, it could be promoting the filamentous algae.

 

[Chaz]

LetortAngler wrote:
I like the dam for one reason. It gives the ditch DEPTH which gives the trout security, and it is pretty much already at the immediate headwater. Maybe the spawn is better with the dam.?
It is after-all the last remaining spring creek that has a class A pop of brookies in the state.
I would hate to jeopardize that over a small dam removal.

Actually there are other Class A brookie streams that are spring creeks. People just don't talk about them.

 

[SteveG]

And anyone who believes that some magical historic strain of brook trout exist there, needs to take into consideration how long that place has been stocked. Not to mention that's it's still stocked with them lol. If there's any historic dna left in the brookies there, it's likely a miniscule amount.

 

[tomitrout]

I actually think it would be neat to raise the dam, create a true mill pond like back in ye olden days of yore and see how big of a brook trout that stream could grow...

 

[SteveG]

If they try that, I'll happily plant some browns from the Letort in there.

 

[LetortAngler]

So, even if a geneticist/biologist was able to obtain data showing the brookies are not 100% hertitage strain (which is most likely, but not yet conclusive) I personally wouldn't deem them any lesser than a pure strain Brookie.
I don't think these fisheries can afford favoritisms over one type of trout over the other. After all, most of Big Spring below the C&R area is about fishless the whole way to the Mill, other than early season stockings. A stream of this quality should not have to rely on planted trout.
For me, what it boils down to is that upper Big Spring remains a stronghold for wild brook trout -pure or not. Even if there are a handful of other limestone/influenced streams that have Class A brook pops, some of them that I've visited, and each as valuable as any limestone stream, but not comparable to Big Spring which is (in fishermens lingo) a "true spring creek".

 

[SteveG]

Here's the rub regarding a supposed heritage strain (of anything). Genes constantly change with each successive generation due to a variety of factors. There isn't a "pure" brook trout strain, it's either a brook trout, or not.

Some think there are Loch Leven or German brown trout strains in the wild, but only a brown trout born in Loch Leven, is a Loch Leven brown trout. A wild brown trout born in Pennsylvania, is a Pennsylvania brown trout. Even clones of Loch Leven trout are Loch Leven, unless they're raised there. An organism's environment weighs heavily on it's genetic makeup.

 

[salvelinusfontinalis]

Steve,

I have to disagree. Genetics are genetics regardless of geographic location.

I can take an Irish couple from Ireland and move them to America. The baby born May be American but it has Irish genetics.

 

[Chaz]

Gens do not change with every successive generation. It sometimes many generations to change. Of course it depends on what your definition of changing genes is.
For instance a stream with a high genetic diversity of genes is preferable to a it having a low diversity. And it is much better across the Commonwealth to have a high diversity of genes in brook trout. They presented information on this at the Wild Trout Summit and one stream came to mind that they talked about having a high genetic diversity is Elk Run. It's an important tributary to Pine Creek. Any stream with a low diversity of genetic diversity is vulnerably to having it's population wiped out by a single even.
Edit: I should probably rephrase that, the genes change but the DNA takes a very long time to change. Genes change but it's important that the ones that fire are the important ones.