Penn's Creek Summer Recon

[barbless]

Spent an afternoon at Penn's doing something I've wanted to do for a long time- swimming it with a mask on, to get that ground-level view and do some fish spotting. I was on lower Penn's in the C&R section.

The fish spotting was pretty marginal. Which was to be expected, I suppose, given the water temps (around 70 degrees) and the low water (around two feet lower than it was this past May.) But it was definitely educational.

The only trout I spotted were in one thermal refuge that I found. ( do not think that the locals will treat you kindly if they find you fishing one of these.)

For what it's worth, the trout did not look like they were in a feeding mood. They looked more like mammals in aestivation (summer hibernation), or maybe like commandos breathing underwater through a straw in a rice paddy until the coast is clear.

fwiw, I saw no anglers on the stream.

The most plentiful "fish" were these guys. By far. The creek is crawling with them. I've never seen so many in one place.

Since I've heard that PA has an invasive crayfish problem, I did a search to see if Penn's was one of the affected waters.

What do you know- it is:

http://blog.pennlive.com/pa-sportsman/2013/07/invading_crayfish_are_eating_our_water_systems.html

"...Other waters with documented non-native crayfish take-over are Yellow Breeches Creek in Cumberland County; Spring Creek, the home of the world-famous Fisherman's Paradise near State College; Penns Creek in Centre and Snyder counties; and Valley Creek in the southeastern corner of the state...."

"...When crayfish invade a new ecosystem, the first impact is a replacement of the native crayfish species that naturally inhabit that water. The aquatic plant community is the next thing to go, and in some waterways that decline has been as much as 90 percent.

Next populations of mussels, snails, caddisflies, midges and other invertebrates decline as the exotic crayfish eat them. Amphibian populations laying their eggs in the water that's been invaded, and then the fish, "especially the nest builders, are impacted.

Invading crayfish also bring unnatural crowding to their new home. While the norm for native crayfish species might be one or two per square foot of stream bottom, an invasive species like the rusty crayfish may be found at more than 20 per square foot. "They can literally stack up on top of each other," he noted..."

"Commission staff plans to bring a proposal to the commissioners at their October meeting to ban all possession and transportation of any crayfish unless the head of the animal has been removed."

I'm fine with outlawing live crayfish for bait in PA. At the same time, I'd like to see the bag limit on crayfish with their heads removed lifted in all of the invasives-affected waters. (current possession limit is 50 per day.)

Crawdads are tasty. At this time of year, it would be no trick to seine out 500 of them from a few hundred yards of stream, and trap another 500 overnight from the same stretch, using a cage and a few sucker fillets. More than enough for a fine community crawfish boil.

As for the actual finfish in the stream: lower Penn's seems to turn into a first-rate smallmouth bass nursery in the summertime. Lots of young-of-the year and 1-2 yer old fish (4"-9").

The only big fish I saw were some huge lunk-headed suckers, and one big smallmouth in the deepest pool where I snorkeled.

The usual rap on fish reactions to human swimmers is that they're unconcerned, and that they usually just go on about their business. Not so in Penn's- every large fish I spotted bolted away at top speed. Probably had something to do with the low water- average depth in the pools and runs was less than 3 ft.

I'd like to go back and do this again some time, on a hot sunny spring afternoon with water temps at least 5 degrees lower, water levels 2 feet higher, at a time of day when fisherfolk are scarce.

 

[McSneek]

So did you see many trout outside of the thermal refuge you found? I would think that although the water temps were/are marginal they have certainly been worse in other summers and many fish would have stayed in the usual spots this year. I'll probably fish Penns once or twice in late Sept. or early Oct. When I go up in the fall I'm always suspect that fish have moved out of a lot of the areas you find them in the spring.

BTW - I think it would be hilarious if you popped out of the water in full snorkle gear in front of some unsuspecting fisherman.

 

[barbless]

(Beware: data dump. And I do use page breaks, because it makes more sense to me than doing six posts in a row.)

The trout may have been there, but they must have been way ahead of me. Other than that one spot I found, I didn't see any- except for one small jumper about 6" in the pool near the east end of the Poe Paddy tunnel, that was most likely a brownie.

The low water and slower current flow makes Penn's look clear in the summer. It's easy to spot fish swimming or holding above the river bottom in the sunlight. But undeneath, it's surprisingly cloudy. So chalky that it's downright hazy. Only a few feet of visibility. I snorkeled a warmwater lake in Maine this summer that was much, much clearer. That also might help explain my lack of success. But I didn't see any trout while snorkeling. None. Zero. I had the distinct impression that they were on summer vacation. If any trout were where I was snorkeling, most likely they were tucked away on the bottom, laying very low in the daylight and the afternoon heat. Panting for breath, while the crayfish cavorted around like they owned the place.

Penn's is actually looking pretty good, compared to some other summers when I've been up there. I tested water temps to be right at 70 degrees in the main stretch of the creek. I've measured August water temps in the same stretch between 74 and 78 degrees in other years. But the creek is still too marginal to fish for trout, in my opinion. The bass fishery downstream where the pools have some depth must be great, though.

Cherry Run was running at about 63 degrees, and very shallow. (No, the thermal refuge pic is not from the mouth of the run.) The trib does add some steady running cool water for around 100 yards downstream. But it was literally too shallow for me to even attempt snorkeling there.

One of the most educational things I learned from swimming the creek with a mask on was how it's possible for the creek to seem to be holding only a few fish in a 100-yard stretch, only to come alive during a hatch with trout rising every two feet. They're hiding under the rocks. Not beside them, in front of them, or behind them- those are only the ones you see. The boulders of Penn's are all jumbled around next to each other, and they typically have large crevices dug out in the gravel along their bottom edges by the current. That isn't obvious when viewing from above the surface, so it's easy to get the false impression that the most of rocks are just sitting more or less flat on the river bottom, partially buried in sand and gravel. They aren't. Almost all of the rocks are laying on top of the river bed, with their undersides as irregularly shaped as their tops. And they're all jumbled and loosely wedged against each other, which creates even more hiding places for the fish.

I guess that explains a few things about nymphing on Penn's, and other streams like it- like how it's possible to get so close to the fish, and catch them from only a rod length or so away. Many of them are sheltered underneath a ceiling of rocks, and they can't see you, just like you can't see them. What scares them more is the sound of wading, and stepping on rocks. Especially loud, fast, clumsy wading.

I've often scared fish in boulder-strewn runs and riffles from right underneath my feet, and I've wondered why they didn't flee sooner- now I'm thinking that it's because they couldn't see me just like I couldn't see them, and so they paid me no mind until I practically stepped on them. That also may explain how it is that there are a quite a few fish in 6" of water in springtime water conditions- with the cooler water and stronger current flow, as long as they can find a rock to hide under, they're fine.

The fact that the trout are mostly hiding underneath the boulders also helps explain why getting the right weighting for nymphs and wet flies is so important- most of the time, the fish aren't going to move up for food, at all. It has to come right past them, crawling along the bottom. They might move a foot or so along the stream bottom to grab drifting nymphs and larvae, but they don't even see anything that isn't in the lowest water column. I think that's why most of the nymphing advice in this forum recommends placing weight very close the fly, like 3"-6". That's just enough distance that the fly looks like it's drifting free, while the shot looks like gravel tumbling along the streambed at the speed of the current.

 

[dryflyguy]

I've always wanted to do this during a nice hatch, and fish are rising well to them. But that would most likely have to be done in springtime - when the water's cold. Anyway, I'm sure it would shed a lot more light on what the fish really see.
One of these days...................

 

[McSneek]

Ozzie Ozefovich's (sp) underwater video of trout feeding supports your comment that the water is cloudy. His video shows a stream that on the surface is absolutely "gin clear" but when he puts the camera below the surface it's much different. Murky as you say. The trout in his video often mouthed and rejected non-food items I think simply because they couldn't see clearly what every thing drifting by them was. Better to inhale it and eat it if it happens to be real food than let it pass by.

I agree that fish would prefer some overhead cover as well.

 

[barbless]

I've always wanted to do this during a nice hatch

I'd like to do the same thing. As much to learn what the bugs are doing as the fish.

I saw no drifting insect life during the time I was looking around with my mask on yesterday. But I did get some idea of what the fish must be seeing in that milky water- they see what's near to them, like within a 1'-2' radius. Since fish have eyes that face to the side rather than in front, feeding trout like to fin around in place to move their heads and widen their field of vision. If you put something that looks like a tasty food item inside that circle, the chances are very good that they'll notice it and try to grab it. They won't turn tail and chase it unless it's something big, like a stonefly or minnow (streamer). But if they see it in front of them or beside them, they'll go for it.

That circle of feeding territory is actually pretty tight. And the trout undoubtedly miss some of the bugs that drift by them. I'm guessing that this explains why it's worth it for a nympher to comb through a run or riffle thoroughly. Especially in a place like Penn's. The trout are there. The most important trick is to get the right balance of weight to tumble along the bottom so the nymph is right around nose level with the fish.

 

[barbless]

McSneek, here's my attempt to take an underwater picture of the thermal refuge, using the "underwater" setting on my camera, from the same distance as the picture I took above the water:

That's a point and shoot, from no more than 3-4 feet from the fish.

I went into my photo editing program to try and get something usable. Zilch. Nothing worked. (It did pretty well to bring out the detail on the photo I took from above, though.)

 

[JF_]

barbless,
thanks for posting all that info, it was really interesting.
John

 

[pcray1231]

Yeah, thanks. This is something that all of us tell ourselves we should do. And we really should just go out and do it. But we never do.

A sort of tangent, but this gets me thinking. The general rule of thumb is that other than a large baitfish or something, a trout in a fertile waterway won't move far for a meal. You gotta put it right in front of them. While a trout in an infertile freestoner will move clear across a pool to hit a small dry fly, much more aggressive.

We usually attribute that to availability of food. Food more available = fish don't have to waste as much energy and can stay put and wait for food to come to them. When food is less available, they have to go after what they can get. But how much of it has to do with clarity, rather than aggressiveness? i.e. more fertile waters are simply cloudier.

I don't know the answer. Your findings here just got my mind going a little, and I typed it.

 

[pcray1231]

You're last picture also shows why BLACK is such an effective color for streamers. We consider whites and silvers to be "brighter", but in a limestoner, are they really?

 

[Fishidiot]

Neat! I've done some snorkeling on warm water rivers such as the Juniata, mainly to try to get a better feel for the under water environment for art projects. I've had much better success doing this in shallow salt water where things are usually much clearer than PA rivers.

As for the crayfish, the one in your pic appears to be a rusty but I'm not sure. This time of year, crayfish - probably the invasives - can be incredibly dense, so much so that each step you take can drive a dozen. Their numbers can be almost unbelievable in some waterways by mid summer.
Maybe it's time for the first annual PAFF Crawdad Jam!

 

[barbless]

A Crawdad drive. Set up the seines, shoo'em downstream, sort the fish out, divvy up the catch.

I doubt that seine nets would be legal, come to think of it. But it would be no problem to limit out on crayfish in Penns by other means, like fine mesh frog nets or a few chicken carcasses on the end of a rope.

 

[Hook_Jaw]

lmao