How to Imitate Caddisflies

(This story appeared in the April-May 2019 issue of Fly Fisherman magazine and was originally titled "Activate Your Caddis: How to add movement to your flies for presentations trout can't resist".)

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Mayflies and stoneflies seem to have celebrity status in the world of aquatic insects, but maybe that’s because they make only occasional appearances and with great fanfare. Caddisflies, on the other hand, seem undervalued and underappreciated by fly fishers, which is a bit of a conundrum. Trout depend heavily on these blue-collar insects as a year-round food source, and successful fly fishers consistently use active caddis strategies as part of their repertoire.

Caddis are found in just about every river and stream in the country. Some members of the caddis family are pollution tolerant, and they often live in streams where many mayflies and stoneflies can’t survive. One of my first duties working for the Pennsylvania Fish and Boat Commission years ago as a fisheries biologist aide was to seine for bugs in streams contaminated by acid mine drainage. Caddis larvae were by far the most prevalent bugs in the samples.

These were streams with orange-colored rocks stained by iron ore and heavy metals, and the water was discolored. Most people would guess them to be dead. However, our electroshocking surveys found small populations of native brook trout. These trout had to be eating caddis. For me, this was an eye-opener about how tolerant some aquatic insects can be to poor water quality.

This lesson was again proved several years later when I began to fish European waters. My time with Fly Fishing Team USA took me to a handful of European countries. While some of the waters we fished were pristine and full of bug life, there were also rancid ditches full of sewage, stocked fish, and caddisflies. However unspoiled or putrid the waters we fished, caddis were usually on the trout’s menu, and it paid to know how, where, and when the trout fed on them.

And this isn’t knowledge that only trout fishermen need to know. Many warmwater streams that are home to bass and sunfish are also loaded with caddisflies, and while I’ve sometimes seen mayflies and other common insects hatch on these warmer waters, caddis make up a large percentage of potential match-the-hatch scenarios here, too.

Some of these warmwater fisheries are also badly impacted by acid mine drainage, yet I’ve seen the water appear to boil with rise forms during massive caddis hatches on these “impaired” streams.

Great caddis hatches are not just a trout stream occurrence, and while you don’t need to be a professional entomologist to be successful on the water, you should understand their habits and life cycles.

Meet the Caddis Family

There are 20 caddis (Trichoptera) families in North America alone, and more than 1,400 species. Caddis go through a complete life cycle of larva, pupa, and adult, and all these stages can provide excellent angling opportunities.

Larvae. There are three broad classifications of caddis larvae types: 1) Primitive caddis (aka free-living or free-ranging caddis) that do not build a case or net. Instead, they cling to substrates, much like many mayfly and stonefly nymphs; 2) Tube case makers that live in a case they build from bits of vegetation, sand, gravel, and debris; 3) Fixed-retreat caddis that build similar shelters or nets. These types of caddis feed outside their shelters but can retreat to them.

Take the time to pick up a few rocks or seine the stream bottom to see what types of caddis larvae are most common in your waters. Keep it simple. If you notice many bright green, free-living caddis larva, fish a naked bright green larvae pattern. If you find a bright green caddis larva protruding from inside a case, then fish a darker-bodied nymph with a tiny bright green head, like a dark version of Sexy Walt’s Nymph with a bright green thorax.

Even free-ranging caddis are not great swimmers. They cling and creep along the stream bottom, so a dead-drift presentation is often the best approach. Depending on stream conditions, both suspension and tight-line nymphing systems are effective for drifting larvae near the stream bottom. My best results occur with medium to heavily weighted Czech- or Polish-style caddis larva patterns. Their sleek, dense designs descend quickly and stay near the bottom throughout the presentation. Most of my favorite larva patterns are quite simple, however, imitation becomes much more important for the pupal stage of the caddis life cycle.

Pupae. All caddis larvae create a cocoon-like housing where they commence their pupal stage. Tube case makers simply close the end of their tube before pupating, while primitive and fixed-retreat caddis have more work to do. Depending on the species, the pupal stage may take several days to several weeks before emergence. When ready, most pupae will begin emerging to the surface. And it’s this stage that makes for some of the most exciting fishing.

I break down caddis emergence fly presentations into two segments. First, the journey of the pupae from the stream bottom toward the surface, and then the period where the pupae remain in or near the surface film. There are at least two different tactical approaches to mimic both ascending pupae and surface-slowed emergers.

Because most pupae begin their emergence near the stream bottom, then travel toward the surface, I believe it’s important to fish this emergence from bottom to top. In a full-blown caddis hatch, trout may be feeding at all depths, so develop a plan that begins with your pupa imitation near bottom and finishes near the surface. A dead drift, followed by a swung presentation, is one way to fish the caddis at all levels.

As Jim Leisenring and Frank Sawyer taught us years ago, an induced presentation (lifting or pulling your nymphs upward), is an excellent trigger for active fish. This Leisenring Lift allows you to mimic the natural insect’s ascent to the surface.

I use a tight-line or Euro rig with a heavier fly at the end to keep the entire rig under tension. A tungsten beadhead pupa is often my first choice for the point fly. I add droppers farther up the tippet and tie in unweighted traditional soft-hackles or wet flies that flutter in the current as the flies initially dead-drift, then swing and swim upward at the end of the presentation. This is when unweighted patterns with lots of movable materials tied on droppers (not off the bend of the hook) consistently outperform weighted patterns.

When I was 13, I saved my birthday money and purchased Gary LaFontaine’s book Caddisflies (Lyons Press, 1989), which is when I was first introduced to his Sparkle Pupa. This was a game changer in my nymphing efforts, especially for caddis hatches. While I still fish a modified version of LaFontaine’s original bubble-shaped Sparkle Pupa, I’ve taken many of his principles and modified them to meet my own tying and fishing needs. I generally incorporate a soft-hackle theme into all of my pupa patterns (weighted and unweighted) and use CDC, ostrich, and emu feathers to create movement on both the drift and the swing.

For my heavy point fly (the anchor fly) I use variations of a soft-hackle with a slotted tungsten bead and jig-style hook. The beauty of jigs is the motion you can add to the pattern, especially with longer Euro nymphing rods with softer tips. Twitching the rod tip or tapping the rod blank with your index finger wiggles the rod tip ever so slightly, sending vibrations down the leader and into the fly. I first learned about this rod tap from some friends who use longer tenkara rods. That little rod tap with a jig hook can create an active presentation (drift or swing) that trout can’t refuse. When you’re fishing, think of yourself as salesperson. Make your pupa come alive and move like the natural. Sell it to the fish!

As much as I enjoy fishing traditional down-and-across, wet-fly tactics, fish need to be active for this method to be successful. A down-and-across approach puts tension on line and leader, which keeps the flies higher in the water column. This is an excellent choice when fish are looking up, caddis are hatching, and the trout are willing to chase insects.

When I notice adult caddis breaking the surface, one of my favorite techniques is to eliminate the dead-drift presentation and just hold a brace of wet flies or soft-hackles directly downstream of my position. The line tension keeps the flies near the surface.

I position myself to hold the flies right in areas where I’ve seen trout rise, especially splashy rises that may indicate trout focusing on emergers.

However, earlier in the hatch or when the fish aren’t chasing and splashing, I keep my flies closer to the stream bottom, where trout are likely to feed. This is the fundamental principle of all fishing—present your flies at the level of the fish. As the hatch progresses, I switch gears and work higher in the water column.

Local Knowledge

For many years I struggled to adequately understand and imitate caddisflies. Reading the right books is a good starting point, and I highly recommended Paul Weamer’s excellent The Bug Book (Headwaters Books, 2016) and Caddisflies (Stackpole Books, 2009) by Thomas Ames, Jr. It’s also important to speak to local anglers, guides, and fly shop staff members. They have detailed, essential hatch information that can fill in the blanks for you, especially as it pertains to their waters. If you ask the right people the right questions, you will save hours of struggle on the stream. Here are a couple of helpful tips I’ve picked up from local experts.

My friend Torrey Collins told me that small black caddis (Chimarra spp., see image #1) are very important on his home water, Connecticut’s Farmington River. Their diminutive size (#18-22) and dark color often make it difficult to notice them. And Torrey believes that a lot of anglers miss fishing one of the most productive caddis stages—the pupa. Many anglers fish the Farmington because of its excellent dry-fly opportunities. They stand and wait for risers along flat water, but many of river’s large trout position themselves near the heads of runs to feed on subsurface pupae. These same fly fishers often report that the trout didn’t react to the caddis hatch, but quite the opposite is true.

Collins also says the Farmington has an atypical caddis the locals refer to as the Winter/Summer Caddis (Dolophilodes distinctus). As the name indicates, these caddis hatch through much of the year. In the summer, emergences are similar to those of most other species: Larvae pupate and then males and females rise to the surface (some species crawl out of the water) to commence mating on land as winged adults (see image #3). But in the winter, all the adult females are wingless, or with only dwarf wings incapable of flight (see image #2). Their pupae rise to the surface, breaking the meniscus, and then the adult females run across the water’s surface to meet the winged males, which have congregated along the banks. Successful fly fishers notice this behavior and twitch, strip, or drag their caddis (pupa or dry fly) along the surface and toward shore.

Anglers in New York and Pennsylvania rave about the October Caddis emergence (Pycnopsyche spp., see image #4), which usually begins at twilight, or after dark, and keeps big fish looking up after dark. Once the hatch is in full swing, you can also use an October Caddis dry during the day as an attractor, fished along logs and tight to undercut banks.

On the Upper Delaware River, Popcorn Caddis (Brachycentrus appalachia, see image #5), which are also known to some anglers as Apple Caddis, hatch around the same time as the Hendrickson mayflies (Ephemerella subvaria), and they often bring good fish to the surface in late morning. Anglers arriving later in the afternoon to fish the Hendrickson hatch may have already missed out on the day’s best dry-fly fishing.

Grannom caddis (Brachycentrus spp., see image #6) are often the first significant caddis hatches for Eastern fly fishers, often hatching in April just before or around the same time as Hendrickson mayflies. The biggest difficulty is that it’s common to see the water’s surface covered with adults without finding a single rising trout. As noted above, that’s often because the trout are feeding on pupae. Just swinging a standard-size wet fly often fails to produce during heavy grannom hatches because there are so many naturals in the water. To stand out, I swing large wets (#10-12) for this hatch, two sizes larger than the naturals.

Grannoms are also very important to Western anglers. Often called Mother’s Day Caddis (and also comprised of Brachycentrus spp.), Western grannoms generally hatch in early May. But the hatch’s timing creates a significant challenge for anglers: runoff. You’ll usually get a few days of good grannom fishing before snowmelt raises and discolors trout waters to unfishable levels. Because there are often tremendous numbers of caddis on the water, it’s important to take an active approach to get your dry fly noticed. One of my tricks is to find a rising fish, cast slightly beyond it, and use the hop & drop technique (with a weighted anchor fly) to skitter and hop the dry into the trout’s field of vision.

An Active Dry Fly

Caddisflies tend to run, flutter, and move more than mayflies after hatching at the surface, so I tend to fish dry flies with an active presentation. One of my favorite emerger patterns is called the Puff Daddy. 

The Puff Daddy is a CDC pattern I first heard about on a trip to Tennessee’s South Holston River. I like to use the highly buoyant Puff Daddy by pulling the dry fly several inches underwater, then release the tension to allow the fly to float back to the surface with a sudden rising motion. This creates the illusion of an emerger busting through the surface film as it becomes an adult. I call this presentation the “puff & twitch.” I use Loon Outdoors Snake River Mud on the final 20 inches of my tippet—just enough to force the tippet to sink during the drift. A short twitch (several inches) of the rod tip puts tension on this portion of the leader, and the sunken section pulls the dry fly under the surface. Then I put slack into the system by pointing the rod tip back at the fly, and the buoyant Puff Daddy “pops” back through the surface film.

Remember, pull the fly only an inch or two below the surface. If you pull the Puff Daddy too far under, it may not be buoyant enough to float again. Keep the twitch short. The one downfall of this approach is that you constantly need to apply desiccant. It’s not uncommon to use an entire bottle of dry-fly powder each day.

After emerging, caddisflies move to nearby streamside vegetation, and eventually mate on land. The females then return to the water to lay their eggs. Some species dive or crawl under the water to lay eggs. For instance, in August, black caddis on the Bighorn River are famous for crawling down your waders and laying gelatinous egg clusters on your boots.

Most caddis deposit their eggs at the surface, often by bouncing up and down or by dragging their abdomens along the surface to release the egg clusters. Trout recognize and key in on this active egg-laying stage. This is when l use a dapping, dry/dropper presentation I call the “hop & drop.”

The technique was first shown to me by my good friend, Chuck Farneth. He showed me how to use the dropper (a weighted nymph) to anchor the rig in the water, then lift the dry fly several inches off the water make it hop on the surface. I’ve found it’s most effective to keep all line and leader off the water and high-stick the dry/dropper, using the rod tip to hop the dry fly.

My favorite dry fly for the hop & drop is Hans Weilenmann’s original CDC & Elk pattern. It has enough buoyancy to suspend the nymph, and the CDC fibers add subtle and lifelike movement during a dead drift.

A tungsten-bead caddis pupa imitation often has just the right weight to serve as an anchor so you don’t “hop” the fly right out of the strike zone. Just as with the puff & twitch approach, you only need to lift the dry several inches off the water, and then set it back on the surface. This isn’t just a searching technique. I often use it on rising trout. You can pause the rig right in front of trout feeding on egg-laying caddis, hopping and dropping the pattern until the fish can no longer resist.

Everyone has their own approaches to fly fishing, and building confidence in your techniques is essential. Over the years, I’ve asked the right people the right questions and developed more confidence in these active caddis presentations versus static dead-drift presentations for both dry flies and nymphs. We all have our shortcomings, and for a long time, basic entomology has been one of mine, but watching and learning how these insects behave in and on the water has improved my game. I hope it does the same for you!

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George Daniel is the author of the new book Nymph Fishing: New Angles, Tactics, and Techniques (Stackpole Books, 2018). He owns and operates the company Livin on the Fly and presents schools, seminars, and private lessons across the country. Paul Weamer is the author of The Bug Book: A Fly Fisher’s Guide to Trout Stream Insects (Headwater Books, 2016) and owner/operator of Weamer Fly Fishing LLC.