Fly Fisherman Throwback: A Case for Caddis

Editor's note: Flyfisherman.com will periodically be posting articles written and published before the Internet, from the Fly Fisherman magazine print archives. The wit and wisdom from legendary fly-fishing writers like Ernest Schwiebert, Gary LaFontaine, Lefty Kreh, John Voelker, Al Caucci & Bob Nastasi, Vince Marinaro, Doug Swisher & Carl Richards, Nick Lyons, and many more deserve a second life. These articles are reprinted here exactly as published in their day and may contain information, philosophies, or language that reveals a different time and age. This should be used for historical purposes only.

This article originally appeared in the May-June 1981 issue of Fly Fisherman magazine. Click here for a PDF of the print version of "A Case for Caddis."

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I doubt that any insect, aquatic or otherwise, has attracted more interest among fly fishermen over the past few years than the caddis. The importance of this widely distributed stream dweller has been brought to light in the recent works of Gary Lafontaine, Ernest Schwiebert and Leonard Wright, among others, and it seems safe to say that with regard to the caddis, few stones have been left unturned.

The widespread effect of the "caddis explosion" is manifested in a variety of fishing techniques developed to represent the behavior of the stages of the insect's life cycle. Skittering, fluttering, twitching and the "sudden inch" are terms that have found their way into the vocabularies of many fly fishermen.

For the fly tier the caddis has opened the door to a new generation of fly patterns. Materials, mainly modern synthetics that were heretofore unheard of as useful to fly-tying, have been used in an array of realistic and effective subsurface patterns. Latex, Swannundaze and acrylic sparkle yarn are examples of synthetic materials that, in the hands of innovative fly tiers, are being transformed into larva and pupa imitations that almost look better than the real thing.

As if the advancements in imitating the immature stages weren't enough, the number of adult caddis variations is even more impressive and seems nearly as numerous as the tiers themselves. Elk wing, delta wing, spent wing, tent wing–the list of dry flies goes on and on.

The facts speak for themselves; the caddis has rapidly attained a status equal to the mayfly in angling importance, and rightfully so. It is surprising, however, that despite this overwhelming awareness, there is still one important element that has failed to receive enough attention: the caddis case.

While not all caddis species share the characteristic, during the larval stage many·of these aquatic insects construct their own miniature dwellings that serve as shelter and camouflage during a substantial period of their lives. This enclosure, or case, is constructed of small bits of stream-bottom debris, such as sticks, leaves or tiny stones cemented into a cylindrical shape with an adhesive secretion from the larva's body. Trout, opportunistic creatures that they are, recognize that these cases contain a worthwhile food item, and lacking the ability to extract the little morsels, they consume the larva case and all.

If you have ever examined the contents of a trout's stomach, you've probably seen evidence of caddis cases. The cases may be found intact or broken into small pebbles or bits of twigs–all that remains after the larva and case have been broken down by digestive juices.

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That trout consume occupied caddis cases is fairly well known. But there are those who contend that imitating and fishing casemakers is a waste of time. They point out that the casemaker spends most of its time hidden among rocks or submerged vegetation and is relatively unavailable to trout. Keep in mind, however, that all immature aquatic insects share this self-protective trait. I don't know of any insect that voluntarily offers itself to a foraging predator. A basic difference that should be considered is the casemaker's lack of mobility. Burdened by its cumbersome case, the casemaker is probably more vulnerable to predation than insects that are able to scurry or swim to safety.

Gary LaFontaine, whose knowledge of caddis behavior probably exceeds that of any of the angling entomologists I've met, contends that caddis larvae drift freely in the current and may be even more important to trout than their noncasemaking counterparts. Casemaker larvae are worthy of attention from fly fishermen.

Late winter and early spring is a quiet time in Yellowstone country, and the great rivers of this area are normally reserved for those fortunate enough to live here. The marvelous hatches of the Madison, Yellowstone and Snake rivers, along with the hordes of anglers that accompany them, are distant memories of another season. It is a time when the trout of these streams, if they are to survive, must direct most of their attention to immature insects that dwell toward the bottom.

Patience, determination and mastery of a technique known as "bottom nymphing" are essential to successful off-season angling. The object is to keep the fly as close to the bottom as possible and moving at the same speed as the current or even slower. Natural movement of underwater residents, including both fish and insects, is slowed by water temperatures chilled by frosty nights and the beginning of spring run-off. As a rule, any erratic behavior in the angler's offering is met with disdain by even the hungriest trout. To put your fly down on the bottom in a position acceptable to the trout, you must cast a weighted imitation upstream and, keeping a tight line, follow the course of the drift by focusing your attention on the point where the line enters the water. The slightest hesitation or twitch in the line is the signal to strike, as the take is likely to be gentle.

Some anglers like to use short leaders and full-sinking or sinking-tip lines to get the fly down where it needs to be, but I prefer a floating line and a fairly long (eight to twelve feet) leader. The amount of weight required to get the fly down and keep it there varies according to stream depth and current speed, and you may have to add weight using lead strips or small split-shot on your leader.

Once perfected, this technique can be extremely effective, but it is not always as simple as it might sound. Selection of the proper pattern is particularly important. Since the object of the trout's attention is concealed beneath the surface, a thoughtful process of fly-pattern elimination has become the standard procedure. A reasonably thorough knowledge of the stream's insect population is helpful, but on more productive waters the possibilities can seem almost endless. Keep in mind, however, that the trout is a predator, an opportunistic creature who, much like the cougar that singles out the weakest member of a deer herd as its prey, recognizes vulnerability and concentrates its efforts upon the prey least likely to escape. The casemaker caddis larva is one of the most defenseless of the many stream-bottom organisms trout eat. Its vulnerability should be considered when you're trying to decide on the right fly.

An experience I had while fishing the lower Henrys Fork several years ago provides a graphic example of how trout can key on casemakers despite the presence and apparent availability of other insect forms.

It was early April, and according to the calendar spring was underway. A trudge through two hundred yards of knee-deep snow to reach the river and the great banks of ice that lined the water's edge were harsh reminders of winter's reluctance to depart. Huge flights of northbound waterfowl and a midday sun that warmed the water's surface gave hope for a changing season.

The Henrys Fork ran cold and clear over a clean gravel bottom, and a sparse hatch of early Baetis was·on the water, the first of a multitude of mayflies that would appear in the ensuing months. The trout were small but enthusiastic, and I was having success fishing a #20 Quill Gordon on a choppy, thigh-deep riffle.

I was content until I began to notice flashes of red and silver well beneath the surface, an indication that the riffle's larger inhabitants were directing their attention at something on or near the bottom, not at the tiny mayfly duns.

Retrieving the line, I clipped the fly from the 5X tippet and modified the leader to accommodate a large, weighted stonefly nymph. The pattern had proved its worth on many occasions, and I confidently extended twenty feet of line, dropping the nymph well above several feeding trout. Holding the rod tip high and stripping the slack out of the line, I tensed in anticipation as the fly bumped along the bottom. The fly completed its drift untouched. I repeated the process; again there was no strike. A dozen more casts met with the same indifference, and a change to a peacock-bodied favorite didn't help.

Finally, on the fourth or fifth cast with a #12 Gold­ Ribbed Hare's Ear, I detected a slight twitch in the line and instinctively raised the rod tip. Instantly a scrappy sixteen-inch rainbow shot from the bottom and cart­ wheeled into the air. The battle was brief but spirited, and a few minutes later I was admiring a surprisingly well-conditioned trout. Its distended belly showed me that it was having no trouble finding adequate nourishment.

As I freed the Hare's Ear from the trout's lower jaw, I noticed several strange sticklike objects collected in its gillrakers and around the opening of its throat. Reaching into its mouth, I caught one of the objects in the jaws of my hemostat, and after releasing the trout I held it up for a closer inspection. Caddis cases! The trout had been gorging itself on casemaker larvae. This explained its lack of interest in my earlier offerings.

Resuming my casting, I again probed the depths of the riffle, and while the results were short of spectacular, several more good fish fell prey to the Hare's Ear over the next few hours.

It was a memorable day, not that I had taken many trout, but I had gained valuable insight into another of the many complexities of trout selectivity. Driving home that evening I pondered the day's events, and my thoughts kept returning to the pattern that had finally done the trick on those finicky rainbow.

The gold-ribbed Hare's Ear is one of our most popular nymph patterns. Simply constructed of the bristly fur from the face and ears of the European hare and ribbed with fine gold tinsel, it represents nothing specific, yet has probably accounted for more trout than any single subsurface artificial. That the Hare's Ear bears more than a slight resemblance to a caddis case is probably coincidental, but I suspect that more than one trout has mistaken it for that very thing. It is also possible that many anglers who have frequent success fishing a Hare's Ear are, unknowingly, imitating the casemaker caddis.

To my knowledge, there have been few flies designed specifically as casemaker imitations. But although I don't recall the author's name or the publication in which it was published, I do recall an article a few years back that dealt with fishing casemaker patterns.

The article told of trout that displayed a fondness for encased caddis larvae. The writer's caddis case imitation wasn't really an imitation at all. He attached the discarded case of a real caddis larva to a hook–a solution which, while possibly effective, leaves something to be desired. I have, however, seen several casemaker patterns that conform to more conventional fly-tying methods, including one designed by Howard West of Scientific Anglers/3M. A few years ago Howard landed one of the best rainbow I've seen taken from the fly-only water of the Harriman Ranch with this pattern, and he claims it has produced well for him on several of his favorite Midwestern streams.

Another casemaker pattern that does a commendable job is the Peeking Caddis. Originated by George Anderson of Livingston, Montana, the Peeking Caddis is a two-part fly that represents a caddis case with the larva peeking out. George is an excellent fly tier and an exceptionally observant fisherman who takes a commonsense approach to both endeavors.

"There's no question in my mind that occupied caddis cases rank high on the list of stream-bottom organisms that trout consume," George told me after a day's fishing on Montana's lower Madison. "The key to tying an effective imitation lies not only in imitating the case but in convincing the trout that it actually contains life."

My observations lead me to agree with George, and the patterns in which I have the most confidence share the two-part characteristic of his Peeking Caddis.

There are many tiers, myself included, who believe that the reflective quality of tinsel, in combination with the translucency of natural fur, produces a subtle suggestion of life that can be almost essential to successful subsurface artificials. In many conventional nymph patterns, tinsel, in either flat or oval strands, is used to create a segmented effect. Casemakers, however, don't have segments, a fact that caused me considerable frustration in my early efforts at creating a workable pattern that would eliminate segmentation yet retain the attributes of tinsel and fur.

Eventually I discovered that by covering an underbody of tinsel chenille with a sparse layer of fur dubbing an impressively realistic case would result. The trick was to apply just enough dubbing to allow random bits of tinsel to protrude from the fur overlay.

When it comes to wet flies it's always a good idea to observe the fly underwater. Wet tests can give you a good indication of whether the fly accomplishes the effect you want. When submerged, the new caddis case exceeded my expectations. Its exposed bits of tinsel produced just the right amount of flash, while the remainder-covered by a thin veil of fur produced a definite, yet subdued, reflectivity that was unapparent when the fly was dry. The two levels of reflective intensity, along with the spikey hare's ear dubbing combined to produce an impressive representation of the casemaker's handiwork.

The use of a tinsel chenille underbody and a dubbed fur overbody need not be limited to caddis cases. Its unique effect can be used in other subsurface patterns for both lake and stream. Tinsel chenille comes in gold and silver and, to my knowledge, is available in only one size that is roughly equivalent to medium-size, conventional chenille. Since casemakers vary in size, one might think that this material would be limited to use in larger patterns. Fortunately, however, after the chenille has been applied to the hook shank, it's simple, using sharp scissors, to trim and shape the underbody to the desired size, allowing the material to be used in patterns down to #16.

When imitating larvae that build leaf or stick cases I like to use the coarsest mixture of fur possible to imitate the rough, bristly cases that characterize this type of caddis. In addition to the hare's ear blend described, squirrel-body and seal fur make good caddis-case dubbing. The soft, translucent fur of muskrat, beaver and otter works better for imitating larvae that build heavy stone cases, and interesting effects can be created using fluffy fibers stripped from a marabou plume.

Adding the occupant to the pattern is a simple matter of dubbing a band of fur (usually green, yellow or white) directly ahead of the case to simulate abdominal color. Add to this a half-dozen dark partridge or grouse fibers for legs and a pronounced head of black fur. The ratio of case to larva can vary, but I've found that two­ thirds case and one-third exposed larva is a good rule of thumb.

Casemaker caddis are present in many streams through­ out the year, and successfully fishing the imitations of this important insect need not be limited to a particular season or method. The experience I described involved a situation requiring a deeply and slowly fished fly, but I have also seen trout respond well to an unweighted pattern fished dead-drift and just beneath the surface. By varying the amount of weight, you can fish the fly at different depths. The casemaker cannot propel itself in the current, so the artificial must be drifted drag-free for a natural presentation.

Trout fishing is a complex endeavor, and no fly pattern can lay claim to being the sure-fire answer in every angling situation. But if on some occasion you find the fish totally unresponsive to your favorite nymph pattern, the solution may well be a case for the caddis.

Fly Tying: The Casemaker

If you're interested in tying casemakers you should go to waters you plan to fish for information needed to imitate them. Size, case type and larval colors are the three items of greatest concern, and accurately imitating them should produce the results you seek.

The patterns and techniques described are based on the experiences and opinions of only a few anglers. There is no reason why any number of materials and techniques can't be put to effective use. However, the most widely accepted fly patterns (by both trout and angler) are a composite of effectiveness, dur­ ability and ease of tying. The casemaker fits all three requirements.

Variations in type and color of dubbing used for the case and the larva can be used when a specific imitation is called for. I normally tie the fly on a heavy, 3XL hook such as Mustad's 9672, but the curved-shank style, which has gained recent popularity, also works well.

• HOOK: 3XL, heavy wire. THREAD: Black.
• CASE UNDERBODY: Gold tinsel chenille.
• CASE OVERBODY: Fuzzy mixture of fur from hare's mask.
• ABDOMEN OF LARVA: Beaver belly dyed bright green.
• LEGS OF LARVA: Six to eight brown partridge fibers.
• HEAD: Beaver belly dyed black.

Starting at the eye of the hook, cover the shank with close turns of tying thread. If the fly is to be weighted, add 8 to 10 turns of .015-diameter lead wire and give it a good coat of head cement. Form a four-inch loop in the tying thread and place it out of the way in the material clip. Tie in a four-inch section of tinsel chenille and, working forward, cover the rear two-thirds of the hook shank to form the underbody of the case (see photos 1 and 2).

Using the dubbing-loop method, cover the underbody with a sparse layer of fur. Remember to space the turns of dubbing just enough to allow random bits of the tinsel to show through (see photos 3 and 4).

Form the abdominal portion of the larva by dubbing a band of green fur directly ahead of the case, followed by the partridge-fiber legs (see photos 5 and 6).

Form the larva's head with black fur. Complete the fly with a well-lacquered whip-finish (see photo 7).

René Harrop has lived on the Henrys Fork of the Snake River all his life and has fished his home waters for more than 25 years. A noted fly tier and artist, he lives in St. Anthony, Idaho.