Rubber with a great natural feel: .22 ACP (Alluring Caddis Pupae)

To be honest, a nymph is not the first thing most of us think about when reading "rubber with a great natural feel". But this is the case for Henk, my genius stone loach. Henk lives like a genuine oracle in a hollow cow bone in our fish tank. In this honey hole he helps me judging new flies (without a hook point of course). Most of the time he spits the hard nymphs out faster than Clint Eastwood can draw his .44. But Henk surprised me with the .22 ACP nymph. He sucked this nymph like a lolly pop! Over and over again. The magic ingredient was a small soft squirmy detached body.

And now for something completely different...

Henk's divine lolly pop revelation made me reconsider fly design. The soft feel could perhaps result in less fly throw ups and more hookups. The soft feel of the detached body was a must have feature! The next step is to minimise the necessary hardware (steel hook shank, beads) as much as possible to keep the soft natural feel. A short grub hook size 22 (as a minimum) seemed adequate for further experimenting. A short shank is also important for not compromising movement of the body. Remember to use as little steel as possible for this chewing tobacco. The ACP is technically a detached body fly. In this concept the hook shank's only duty is to connect the body, thorax en legs. A size 22 hook (or little larger) fits that bill. But for a 15 mm caddis pupae a hook size 18 is perfect for a furry replica. A small hook keeps the steel as limited as possible and the weight to a minimum. This nymph floats because of the squirmy body and CDC. It’s an all round river and still water pattern, so a lead shot on the line is necessary to sink it. Otherwise fish it as a wet subsurface emerging caddis fly (without polluting floatants).

Henk judging a new ACP

Game of nods: movement is improvement

An accurate observation of the importance of movement is well written in "In the ring of the rise" by Vincent Marinaro. He writes in 1976 lively about a house fly ("a very interesting creature") and the behaviour of the un-catchable trout. In desperation he began to play the game of nods: this is tying a lot of flies with only slight differences in each of them. Each fly is cast and observations are made. A trout showing interest to a fly nods his head prior to a closer inspection. "At the end of the game all the highest rated variations are combined into one desirable en successful pattern". After lots of observations, house fly tyings and refusals, the only successful housefly had antennas that trembled while the trout was close by. Moving lures and flies get the attention of fish. But attention is just the first step in seduction. To trigger a strike, the movement of a micro part of a fly (antenna, legs, body) can perhaps make the difference! Movement is improvement.

Lessons from Lafontaine's Sparkling pupa

A good fly is not just a piece of a soft rubbery body (is it?). There are more triggers on body parts to consider. Unravelled thoughts about triggers on pupa's are found in Bob Wyatt's recommendable investigation of the well known Lafontaine's Sparkling pupa (Fly fishing & fly tying, July 2005) and a few months later by even recommendable Oliver Edwards article "Caddis contrasts and conundrums" (Fly fishing & fly tying, November 2005). Both concluded that the success of this fly was perhaps not because of the alleged "sparkle air bubble effect" and that more research was needed. Bob argued that the success of the fly had to do with translucency and flash (visibility & attention) among other things.

The article of Oliver Edwards showed some fine improved and inspiring versions of a pupae (Ascending caddis pupa/Swimming Rhyacophila Pupa). Also green bugs as the one rowing in my tank. And also on a more or less straight hook, because the abdomen of the swimming pupae is also straight. Two extra trigger features were emphasised: big swimming legs (like corixida) en wing buds. "But remember", Oliver writes, " they are only effective during an emergence when fish are switched on and eagerly intercepting the ascending pupae".

However, Kent Klewein writes something else about pupae. In his article (The Only Two Caddis Pupa Patterns I Really Need to Carry) on www.ginkandgasoline.com he maintained that "trout concentrate their efforts feeding on the pupa stage of the caddisfly the most, and pupa imitations can catch fish throughout the entire hatch. The reason for this is because the pupal stage is one of the most vulnerable and helpless stages of the caddisflies life-cylce and it’s one of the easiest times for trout to feed on them. Furthermore, their emergence period puts them in front of trout longer than any other stage in their life-cyle".

This leaves me confused. A (sparkling) pupae is probably once more no silver bullet, even on a .22 ACP! But fly fishermen don't need silver bullet flies or holy grail flies Malcolm Greenhalgh writes in his Fly Fisher's handbook: "Otherwise the fascination of inventing and testing new patterns will be gone for ever". So let’s toast to all bad flies.

Caddis colour sorcery 

But here is more confusion on the caddis scene, this time about colour. I found out from my fish tank experiments that a pure white caddis larvae (Limnephilus Flavicornis, a still water caddis species) can for instance transform in green or yellow pupae and flies. That's pure magic. It appeared that when caddis larvae pupate they can change colour and swim or crawl as a green of yellow (not white) protein snacks to the surface. To find out more about caddis flies, a must read is the article "Sedge Edges" from David Calvert and Stuart Croft in Fly tying & fly fishing, issue August 2003. And if you like to experiment with Dutch language, the book Wondervliegen 2 by Leon Janssen is also highly recommendable.

 

Caddis trio: transition from larvae (left) to pupae to adult (right) (L. Flavicornis)

So yellow-green can be a good colour for imitating vulnerable hatching caddis nymphs (and some case less larvae). Pupae colour is still a riddle to me. Along the stream we can observe (cased) caddis larvae en adult flies, but see almost never pupae. Most caddis pupae are seen from spooned trout. But another clue for pupae body colour is perhaps the colour of the body of the adult caddis fly. I found out that green-ish bodies from adult flies matched with bright green caddis pupae. That seems logical. To crack the caddis code: there could perhaps be a relation between body colour of an adult and the body colour of a pupae, but not the colour of a larvae. So check the body colour of your favourite caddis adult and use it for a bright pupae nymph. But there is also enough empirical evidence about (hot) orange or red bodies.....so that is perhaps also an option for a pupae pattern. I use green for my .18 ACP but have to test it for effectiveness. That is the big problem for fly ideas in the closed fly fish season: you can only try and test them a few months later. In my fish tank the red ACP (not the green one) triggered an instant attack from Henk’s neighbour Han Solo Stickleback…so I tied a few reds too.

Nymph gynaecology

Besides colour triggers, Vincent Marinaro’s house fly research taught us that minimal motion can be an important trigger too. So why not use that and try to make a squirmy body livelier like a young Elvis on stage? Completely superfluous you might think because squirmy is flexible enough. Perhaps as a 50 mm worm tied on a canon ball, but not at the scale of a 15 mm free floating small caddis pupae!

I figured out a cunning trick and partially snip (with a sharp pair of scissors) the diameter of the squirmy body in segments, leaving only 0,5-1 mm of material in tact. Do this at several places with such an accuracy that makes a gynaecologist jealous. This weakens the short squirmy body resulting in more liveliness and a segmented look. The segmented effect can be enhanced by colouring the cuts with a dark marker pen (see pictures).

 

Cutting and colouring the squirmy tail

Remember that in a drag free drift (a fly fishers Walhalla), nothing is pulling on your fly, so nothing is moving. Even CDC is motionless under water. I cut the squirmy body up because I want maximum possible fly action by the tiniest movement of a dorsal fin or belch from an inspecting suspicious fish. This is especially the case in still water were Rudd or Ide can inspect flies. The squirmy cutting won't make your fly less durable. This stuff is so strong and elastic that this bit will hold the body intact while giving it the maximum lively appearance. The body is now ready and is the main component of the ACP concept (Alluring Caddis Pupae). For the name: a hook size 22 makes a ".22 ACP", a hook size 14 a ".14 ACP" and so on.

To attach the squirmy stuff to the hook shank is actually quite simple. But please stop turning squirmy stuff around hook shanks like it is chenille. Just drive the hook through the squirmy stuff like a worm or a plastic shad on a hook and tie in. For nymphs e.g. caddis larvae that are curved (not like straight swimming caddis pupae) you can try to make the body in an angle by experimenting with stringing the squirmy on the hook. Ideally the body is following the hook bend. This causes the hook point pointing upwards, resulting in less bottom snags. I found out that with a little flame one can easily shape the squirmy in the right shape.

Key contemplations for ACP fly engineering

The highlighted soft natural feel (very slowly pronounced) in this article is a neglected component in our thinking of fly triggers. This is perhaps also the case for “micro-movement” (Vince his house fly antennas). But because there are no more letters to add to our known GISS mnemonic (General Impression, Size, Shape), we have to remember these. My schedule of requirements for engineering the ACP fly contains the following requirements for the body, wing buds, swimming legs and antennas:

• General design: extended body with a small short shank hook and no bead (use a shot on the tippet).

•  Soft feel & micro movement: a body made of segmented squirmy worm, wing buds made of nylon lady stockings (my friends insists using parts from old crotch sections…I don’t care) and legs/antennas made of thin rubbery legs (no stiff feathers). I found out that soft fly parts result in better hook ups because fish can suck flies more easily and deeper (unhooking is a little more difficult: barbless hooks by default!).

•  Translucent colour: a squirmy worm body and a CDC thorax (mainly for trapping shiny air bubbles and also for movement).

• Knotting: I consider the first 30 cm on a tippet as a part of the fly. So please use a flexible tippet and a loop knot for maximum micro movement. Not a standard clinch knot which is impeding action. And if you use leader/tippet rings: also use the loop knot there! I sometimes develop a sudden Tourette's syndrome while tying small flies to a leader in the middle of a stream. I can prevent this with my favourite loop knot: the easy “perfection loop”. It is explained on the web in an excellent Tightline video. Last important thing about nylon: take any nylon you find home!