Graduate School Stoneflies

By Jeff Morgan

When winter first starts to wane, it's time to stock your fly boxes with stonefly patterns.

While a better understanding of entomology has advanced fly tying in many areas, stonefly patterns are pretty much the same as 20 years ago. This month's article will deal with the big stoneflies: salmonflies and golden stoneflies. Next month I'll cover patterns for smaller stoneflies.

My approach to big stonefly patterns is two-pronged: make them as realistic as possible, but don't expend any more time, effort, or cost than it takes to tie standard patterns. Tying quickly is important because stonefly patterns are fished in rocky, pocket water and under the trees, and they draw hard strikes from fish. And that means you're going to lose flies. So the more time you save tying, the more time you have to fish.

One way to save tying time is to avoid "gimmick" patterns. An example is the Seducer, a variation of the Stimulator . This pattern adds KrystalFlash and synthetic fly wing under the elk hair wing. The palmered hackle and dense overwing obscure the view of two underwings, making the "fish view," almost the same as on a standard Stimulator. Patterns such as this waste money and, more importantly, tying time, so don't fall into the trap of just copying what you see promoted.

Nymphs

Large stonefly nymphs are unique: they occur almost exclusively in swift, rocky water. In this type of water, trout are forced to make feeding decisions quickly. When a large piece of (potential) food comes by, a trout doesn't have time to count wingcases or abdominal segments. When tying stonefly nymphs, function (how the fly fishes, how durable it is, what role it fills for you) is more important than exact imitation.

With that said, you simply cannot snub basic entomological reality. Chiefly, those bright yellow and golden yellow "golden stonefly nymphs" need to go in the trash. There just aren't any stonefly nymphs of that color, except the tiny perlid stoneflies (Alloperla, Isoperla). Natural golden stonefly nymphs have a dark, nearly black back, and a lighter underside.

For big stoneflies, colors should be black for salmonflies and black-over-yellow for golden stones. I also carry a few salmonfly nymphs in a very dark chocolate brown, which matches the naturals on some streams.

When stoneflies are in your hand, they act sluggish, but when drifting they do one of two things: curl up until they make contact with the bottom, or rapidly move their legs as they try to grasp the substrate.

I try to match both of these behaviors. For the rapidly moving legs, I use black superfloss, which jiggles at the slightest movement. For the curl, I like a radically curved hook like the Mustad 37162. While I am infatuated with Dai Riki hooks, their stonefly nymph hook (700B) has a nearly inperceptable curve once the fly is finished.

Functionally, stonefly nymphs pose headaches for anglers because they can be laborious to tie and you can lose many every day due to hard strikes and hang-ups. In my younger days as a commercial tier, I got an order for 60 dozen Kaufmanns Stoneflies It was worst order I ever took, and I have spent the last 7 years trying to develop alternatives to that dreaded pattern.

Two things that I use to help accelerate the tying of stonefly nymphs are a body-stretch abdomen and a sparkle chenille thorax. This eliminates the dubbing, which is quite time-consuming on large patterns. It also has a more realistic effect, matching the hard exoskeleton of the natural stonefly nymph.

For the wing cases, I favor raffia (or swiss straw). It is more durable, simple, and realistic than turkey quill. The raffia must be treated with Flexament before use (preferably twice), which keeps it from absorbing water. When the fly is finished, I often add one more coat of Flexament over the wingcases. This yields a durable wingcase that matches the proportions and color of the natural. (If you look at a natural, you will see that salmonflies have dark wingcases that are nearly the same color as the abdomen. Turkey quill, in contrast, is an unnatural brown which contrasts with the near-black of the natural. It wouldn't be a big deal, if turkey quill didn't take longer to work with and fell apart so quickly.)

Two things that you may notice about the Rocky Nymph is that it is not flattened and that it doesn't use bright beadheads. While golden stone nymphs can be flat, salmonfly nymphs are round. I have always done better with round patterns, possibly because flattened imitations can tumble and spin when they drift. Secondly, I only use dark beadheads with these nymphs, as stonefly nymphs don't have an "air bubble" or any other anatomical structure that the gold bead would match. A properly sized black bead approximates the head well.

Remember, that exact imitation is not needed. I tie my flies this way because I can tie these patterns faster than Rubber Legs or other less realistic patterns. As long as you account for the major keys--basic silhouette, size, curling, and leg movement--you will do well.

Adults

The biggest difference between big stonefly nymphs and big adult stoneflies is that the adults fly around and can wind up in slower waters, even on lakes. On Island Park Reservoir on the Henry's Fork, Quake Lake on the Madison, and other waters throughout the west, it is not unheard of for adult stoneflies that hatched in the swift inlet or outlet water to wind up on the lake's surface because of high winds.

During peak emergence and egg laying activity, trout in normally slow pools or eddies see the big stones as well. While fast water fish are aggressive, fish in slower water are suspicious. They will bump, swirl at, and often, just plain refuse adult patterns--especially the high riding standard patterns that fill most anglers' fly boxes. It is for these fish that a variety of patterns, in different sizes and styles, can make a surprising difference.

With adult patterns, I try to approximate the natural colors, something that hasn't been done much in the past. Most standard salmonfly patterns are orange, but besides the hot orange between the head and thorax, where is the orange on the natural? The natural's body, even the belly, is as slate gray as it is orange. Its wings are also a dark, heavily veined gray color. How many fish have been caught on orange patterns with light elk-hair wings? Innumerable, to be sure, but how can it hurt to imitate the proper color? I carry colors that range from black to slate gray to orange, and combinations of both, and each has their moments.

Also, an adult salmonfly is a flat insect, yet many patterns have tall "downwings" over the back. I like to tie my patterns--even "skaters"--with a low floating/flat silhouette. If the fly is also tied with buoyant materials, it will fish well in both the fast water near where the nymphs emerge as well as the slow waters where vagabond adults can wander.

Another thing you may notice on these adult stonefly patterns is the big black ball on the end of the abdomens. This imitates the egg sac of the females. Like all other insects that lay their eggs on or under the water, female stoneflies are consumed at a much higher rate than male stoneflies. It may not make a difference, but anytime it takes five seconds to make a pattern more realistic, I am going to do it.

The My MacSalmon pattern is a synthesis of my adult approach. I liked the original, but some things needed to get pared down. A clipped deer hair head usually takes more time than it is worth, so that got changed into a bullethead. The body is a dark orange macramé, not the lighter orange of the original, and I will occasionally paint the sides a dark gray color. I added an underwing of Krystalflash and turned the wing into a sparse wing of dark, long elk hair. I took out the "high visibility" overwing, because it stood too tall, wasn't natural, and--let's be honest--if you need a "high vis" wing on a size 2 salmonfly, maybe you need to get new glasses. Oh yeah, the rubber legs are there just for fun.

The Low Ball Stonefly is probably my most effective adult stonefly. It floats very low in the surface film, like a trapped natural, but the thick CDC wing and foam back ensures that it doesn't sink. With the exception of the CDC wing, it is a flat bug. If you look at it from underneath you'll see why it is so deadly: the silhouette is a near-perfect match of the natural.

The Titanic Stone is what I use after the main flurry of action has passed. Most females have laid their eggs, and the trout lay content and gorged. They've been pounded by frauds for two or three weeks, and they are savvy enough to recognize that the action has passed. A big surface pattern is out of place. At this time, sunken adult stones can be effective, and the Titanic Stone fills the niche. I threw in a bead thorax because I often use the fly on sighted fish and I want to be able to control the depth better than I can with an unweighted pattern.

Tying Instructions

Click the links below for tying and fishing instructions.

Rocky Nymph
My MacSalmon
Low Ball Stonefly
Titanic Stone

Jeff Morgan has written many articles for Westfly, mostly on entomology and fly tying. He is the author of An Angler's Guide to the Oregon Cascades and Small Stream Fly Fishing.