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3. Brachycentrus Pupal Behavior

What's known about Brachycentrus pupal behavior? I'd like to "be there" when the time comes.

Hi Paul,

On The Lower Sac, we are entering prime time for the Grannom. These guys are diurnal behavioral drifters, so a popular rig is to deeply drift a pair of nymphs to imitate both the cased larvae and pupae. Peacock Twist Nymphs and some version of the Prince are popular for the larvae (though I prefer my own cased caddis pattern) and flies like the Poopah or LaFontaine Deep Pupa for the pupal imitation. The pupa is an olive or green color, often with a dark back. On smaller creeks without much depth, it might pay to dangle a larvae off a section of white tippet working the riffle pockets with a downstream presentation against tension.

The empty cases you found are probably last years leftovers (or perhaps a few early emergers) as they stay in their cases expanding as they grow and seal them off for pupation. Once leaving them for emergence, they will drift along the bottom for some distance and then again they will drift for a while at the meniscus. They struggle a bit to get out of their shucks, but then fly off fairly quickly. Luckily they are open water emergers as opposed to migrating to the shallows or shorelines as their larger cased relatives often do.

Thanks, Kurt.

The empties I think may have been winter-killed individuals as they were afixed to rock tops as if they were actively feeding, which the live ones may not be yet; Still pretty chilly where I collected them.

I don't know about Winterkill, though perhaps a flash freeze could have caught them off guard I suppose. They are usually pretty adept at staying away from freezing water. If there not last year's castoffs or early hatchers, most likely a pack of stoneflies wandered up there and jerked them out of their cases for a feast.:) Other caddis larvae too. I've often noticed cases that would crawl around and then lock together in my collecting trays. Upon separating them later, one would be completely empty!

Paul,

Here's the Grannom Larva I was referring to. It is very heavily weighted with a full body wrap of .020 lead shoved into the black bead. The square case, moving green body, and flowing black emu fiber legs are the triggers. It works much better for me than the front mounted stiff body and leg designs that are common. I also think the head down orientation when it drifts is more natural and that could be a trigger too...

I really like this one as part of a two fly nymph rig during grannom season. Its been a real performer, often out-fishing the pupa pattern I sling below it. When the fish are working near the surface, I usually switch to the pupa I've posted before, or on occasion the dry (whenever I can get away with it).

Reversed Peeker Nymph - Grannom #14

I have had fairly good success with this...

Nice fly, John. Herl is a popular and effective case material out here too. I prefer hair only because I can shape it to the square cross-section of the natural. Is that turkey tail?

Thought I'd posted the pupa before, but guess I didn't. That was a Hydropsyche. Here's the Grannom Pupa. This one's been "fish approved" (notice the ripped wing).

Halo Pupa - Grannom #12

Kurt, pupa looks great!

I wrapped darker pheasant tail barbs over weight, dark dubbing and than cemented it.

After studying several different videos of caddis pupa rising to the surface I am beginning to wonder about adding 2 legs protruding from each side. They seem to be fairly strong swimmers. This is leg action I see...



So besides the gaseous sparkle, shape, size and color are the moving legs possibly another trigger?

Absolutely! Especially for stillwater caddis pupa and the diving hydropsychid adults. I noticed this behavior years ago when I mistook a Spotted Sedge adult for a waterboatman. The big pharates of the Limnephiloidea superfamily can look like water striders going across the water. Paul and I were discussing this in another topic not too long ago. We are both working on prototypes.

Nice flies guys. Love to see other's concoctions.

John, I've been ruminating on the pupal legs for some time.

When I first witnessed it I too thought of the waterboatman. Since then, I have been in the prototype thinking stage. I might try one idea this weekend if I get a chance and drop in some water to see how it appears. Although, my main focus is turning to a bamboo fly rod blank that I have on order, which should be here sometime next week.

Kurt & Paul, since you both seem as nitpicky and deep-thinking as me (maybe even more), let me know what you think?

http://flypatternsfortrout.com/2012/03/23/why-is-hans-weilenmanns-cdc-and-elk-pattern-so-effective/

I dunno. I guess the emerging caddis I've seen have left the shuck behind pretty quick. But...I certainly haven't seen it all.

As to the swimming pupa I tried ultra-fine rubber and it was too stiff. Going to have to be a feather.

John -

I'm with Paul on the caddis versions. Maybe it's a western thing, but I haven't had much luck with similar experiments for them, even though we do have species like the grannom that can struggle a bit to emerge. The best examples I've seen are Gonzo's, and I assume eastern trout agree or he wouldn't have put them in his book.


Paul -



Have you tried nymph legs brand? The stuff is so fine guys are using it spin-dubbed in a loop for woolly bugger bodies. My problem is the opposite with it though. It isn't obvious enough. The trick is to get the material to flow back like a bug kick yet with enough resiliency to spring back when forward motion has stopped. It shouldn't look mechanical like a stick on a hinge, but rather flow.

You know those worthless hackles that are almost all web that always seem to sneak into a pack of strung saddle? They kinda look like schlappen only stiffer. Anyway, clip an appropriate sized section out (quill and all) and tie it in under a wingcase (a size 12 should have 4 or 5 fibers to a side). if done properly, the barbules should stay married. That's what I've been working on. The jury's still out on river caddis because they haven't been tried enough, but they work great on the boatman and larger stillwater pupae. Tie a few up, Paul and pulse retrieve them in the bathtub - I think you'll be impressed.

John,

I think the reason that caddis emergers aren't often worth the trouble is because the important families that emerge in open water generally do so in runs or riffles moving at a pretty good clip and they get up and out pretty fast.

However, I wrote too broadly in my first response and would be terribly remiss if I didn't add the following. The exceptions are the excellent Brachycentridae and Lepidostomatidae hatches on our spring creeks or the slower runs and pool heads of some of our freestones. I've had excellent results with a Cutter EC-caddis (with some important modifications), to the point where it is my second favorite caddis dry to use on these waters. I had a fellow out with me just last season who landed a very choosy 22 incher on one. I wouldn't fish the Henry's Fork without them. Another gooden' is a halfback LaFontaine Sparkle Pupa, but I consider that a pupa in the meniscus rather than an emerger, per se.

BTW - The picture of the emerging caddis in that link is grossly misleading because of the lighting.

Kurt, you're right. After reading your comments I went back and read what I said again and changed it. I rushed when I did it waiting for dinner and March Madness BB games. I meant it as a possible theory to ponder about why the CDC & Elk with long trailing CDC fibers is so effective, along with other thoughts. And your example of Cutter's E/C Caddis is another example of a trailing shuck on an effective caddis pattern.

Oh, now I understand. Yes, undoubtedly it's because the CDC simulates the trailing shuck and makes the fly look alive.

Any thoughts on the Iris Caddis?

Are you talking about that X-caddis variation that has a z-lon loopwing substitute for the deerhair wing? If you are, it looks like a mayfly emerger to me. Perhaps a good fly to imitate both if an angler is looking to reduce the numbers of patterns to carry. Very buggy looking fly.

Yep, that's the one. I met an experienced angler last season on the Delaware, who absolutely swore by that fly for the apple caddis. I have yet to test it out, but have tied a few for this season. The loopwing is tied horizontally, rather than vertically as in most mayfly loop wing flies.

http://www.orvisnews.com/FlyFishing/Tying-the-Iris-Caddis.aspx