Fishing the iconic Salmonfly (Pteronarcys californica) hatch on the Fifty-Mile Riffle is an epic experience to say the least. Snow-capped mountains and lush green hillsides frame a robust river flush with the bounty of early season snowmelt. Tremendous browns and rainbows rise eagerly to engulf massive insects from the surface. It’s the stuff of legends.
Though, like many phenomenons, they are all too often elusive. One day you’re a bit too far upstream of the hatch, the next day you’re too far behind it. Sometimes you’re right smack in the middle of the hatch, but the fish have seen too many bugs and reject your fly as if to say “sorry Sucker, better luck next time”.
Every so often, when the stars align, you get to watch in amazement as big trout erupt on your dry fly, and tear upstream in a violent and powerful run. On days like these you can do no wrong, it’s as if every trophy trout in the river has been waiting all year just to eat your fly. Though, sadly, that’s not the norm. The reason those epic days are so special is because they so rarely happen.
I’ve spent many days watching perfect drifts go unrewarded during the Madison’s salmonfly hatch with perfectly presented stonefly imitations. Over the years I’ve been forced to look past the obvious attraction of the Hollywood Hatch, and look deeper for other ways to feed these crafty trout. More times than not, the answer has been with Arctopsyche grandis.
Arctopsyche grandis is a large (size #8-10) chocolate-colored caddis that is conveniently at its peak of activity on the Madison River when salmonflies are hatching.
A. grandis are predominantly nocturnal, but at their peak abundance, the sheer volume of insects provides an ample supply of unlucky individuals who fall or get blown from stream side vegetation into the drift. Just like Salmonflies, Arctopsyche adults can be seen fluttering haphazardly across the surface, especially close to the banks, on windy afternoons.
Conveniently, many of the Madison’s best brown trout occupy those prime lies along the bank, hunting opportunistically for any and all insects that come their way, not just the immense stoneflies.
I generally prefer to present a single dry fly to these sneaky bank feeders. I like a 10-12 foot leader (depending on wind), with a long 2-3 foot tippet section of soft monofilament. When casting from the drift boat, I find a downstream presentation with a reach cast to be the most effective. When wading, I like to approach from below my target, fishing upstream with an elevated pile cast and a slight reach to the bank side.
Dry fly patterns like a size #10 Royal Stimulator, #10 Micro-Chubby, or #10 PMX are all great searching patterns when Arctopsyche are active. All of these flies are also great imitations for the multitude of smaller stoneflies which are present at these times.
When dry fly fishing isn’t producing, often in the week or so leading up to the hatch, larval imitations of A. grandis can be seriously effective. These large larvae are found in size #8-10 on the Madison with a bright olive body and a dark brown head. Nymph patterns like the BSA Beadhead Caddis Pupa, and a Tungsten King Prince are a great choice.
Don’t get me wrong, on days when the infamous fish on the Madison are crushing Salmonfly dries I will cast them until my arm falls off. But when they’re not, you will most likely find me fishing an Arctopsyche imitation….with a bent rod.
So, keep an eye out for these large, chocolate-colored caddis the next time you’re fishing the Madison during stonefly activity, and keep their imitations on deck if you’re watching too many of your own perfect drifts with a Salmonfly go unrewarded.
Years ago, Gary La Fontaine tied the original buzzball on the Missouri River. Some say this fly looks like dead and decaying matter often seen floating in back eddies and that Gary tied the fly for midges shucks while hanging out at the Trout Shop in Craig. The hackle points touch the water in numerous places, making this fly buggy as all get out. I can’t really remember exactly when I came up with my version of the buzzball, but it was on the Missouri river in July during a caddis, probably around 2006 or so. My boat was on anchor in between the Trestles and we had fish eating caddis about 20 feet away. They wanted the buzzball but it was hard to see, the night before I had tied in a compara dun wing along with a trailing shuck so we tested the variation. It drifted through the pod and fish moved out of their lane to eat our buggy bug. A few springs later, our buddy Jake Chutz at Montana Fly Company coined the name “Comparabuzz” after the two of us spent a few days fishing midges on the Missouri. I tie this fly in several color combinations and have fished it all over North and South America with the great success. Our friend and fellow guide in Esquel, Martin Weaver, called me before my trip to Argentina cancelled (I am supposed to be down south right this very minute) to make sure I had tossed in a few dozen of these for him; this is one of his go to flies on Rio Tecka.
Originator: Joe Moore, BSA Co-owner
Hook: MFC Model 7000, TMC 100 or equivalent, #14, 16, or 18
Thread: Unit Thread 8/0 Black
Tail: Sparkle Emerger Yarn, Brown
Wing: Deer Hair or Widows Web, Light Tan
Hackle: Brown and Grizzly
Color combos – these all work well for midges, caddis and mayflies. Smaller stone flies as well.
Aquatic, stream-side entomology can be intimidating. There’s all that Latin to remember, and just when you start to feel like you know what you’re talking about, the taxonomy changes, and there’s more Latin to learn.
Luckily for fly anglers, trout don’t speak Latin and they could care less about taxonomy. A strong understanding of the behavioral characteristics, and the habitat requirements of different insects is far more valuable to the average fly fisher than the ability to differentiate between Baetistricaudatis and Baetisbicaudatis or distinguish posterolateral spines from gills.
Few insects exemplify this more than Rhyacophila (Rhy-uh-co’-fil-uh) caddis. This unsung hero of the caddis family is vastly important on Yellowstone Country rivers like the Madison and Gallatin. Yet, how they live, and where they live in our waters is a mystery to many anglers.
The most unique characteristic of Rhyacophila caddis is also the most important for fly fishers to understand. These are free-living caddis. The larvae don’t build a case, or spin a net. Rather, they roam freely on the bottom substrate of our rivers preying on other insects, detritus, and aquatic vegetation. This means that for the 30 or so weeks that it takes a larvae to mature and prepare to pupate, Rhyacophila is in the drift and available to trout making it one of the most abundant food sources in rivers where it is found.
Finding Rhyacophila caddis requires knowing a bit about their anatomy. Rhyacophila larvae have no gill structures, instead oxygen is absorbed directly through the skin. This demands water with high levels of dissolved oxygen. The cold, high gradient sections of the Madison, Gallatin, and many smaller headwater streams in Yellowstone Country have such water, and produce strong populations of Rhyacophila caddis.
The larval and egg-laying stages of Rhyacophila caddis are by far the most vulnerable to predation by trout, and the most important to imitate for fly anglers.
Larvae range in size from 14-16, and have a bright, almost neon-green and mottled-brown coloration. In absence of a shelter, Rhyacophila larvae will drop anchor lines of silk to secure themselves to rocks as they graze for food. This is a tenuous predicament in the rough and tumble waters of a river like the Madison, and a great number of larvae become dislodged, both accidentally and deliberately, into the drift.
Pupae are strong swimmers and quick emergers making them a tough target for feeding trout. Once they’ve left the water, the size 14-16 adults, with olive bodies and charcoal-speckled wings, spend little time on or near the water until females return to oviposit.
Female egg-layers dive to the bottom of the water column and lay their eggs with a string of silk on stream bed rocks. Once the eggs have been deposited, the females then drift haplessly in the current, slowly ascending back to the surface where they struggle to re-emerge from the water column and lay spent.
Two species of Rhyacophila caddis are found in Yellowstone country, R. bifila and R. coloradensis. Both species have virtually indistinguishable characteristics, and it is of no value to the fly angler to differentiate between the two.
While Rhyacophila larvae are present in the drift throughout the entire season, it is in the months of September and October, when all of our highly publicized summer hatches are gone and aquatic insects are at a premium, that these caddis are most important.
So, whether you memorize the Latin or not, be sure to remember these free-living, size 14-16, bright green caddis larvae the next time you are nymph fishing in fast water throughout Yellowstone Country, especially in September and October.
Caddis are commanding members of the aquatic insect community on all of the trout waters in and around Yellowstone Country. From April through October, there isn’t a day that goes by without some sort of Caddis activity. Of the dozen or more different types of Caddis that produce good fishing in Yellowstone Country, the genus Hydropsyche is the most important. From May through August, Hydropsyche Caddis consistently produce more quality fishing situations than all of the other Caddis combined.
There are four unique species of Hydropsyche found in Yellowstone Country, and luckily there’s no direct benefit to differentiating between them for the fly angler. All four species have tan bodies, wings that range from tan to speckled brown, and vary in size from 14 to 16.
Next to Pale Morning Dun mayflies, there is not a more ubiquitous insect in Yellowstone Country trout waters than the Hydropsyche Caddis. If you are fishing moving water anywhere in our region you can find Hydropsyche in the larvae, pupa, or adult stage.
Hydropsyche larvae are net spinners who build unsophisticated shelters out of silk that double as a food catching structure. In his groundbreaking work Caddisflies, Gary LaFontaine reports observing Hydropsyche larvae using a silk anchor line to hang in the current as a method of migration from rock to rock. LaFontaine even went so far as to experiment with white-colored tippet to imitate this anchor line.
When Hydropsyche larvae begin metamorphosis and start the transformation to pupa they seal their rudimentary case with silk and remain entrenched for 2 to 3 weeks. The adult Caddis slowly grows within the pupal cuticle until it reaches maturity. Once mature, the insect chews its way out of the sealed case and begins it’s emergence.
Emerging Caddis pupae are, most simply, a fully formed adult draped in a thin pupal cuticle filled with gas bubbles. Hydropsyche pupae ride the current near the bottom for some time before rising through the water column. Once they reach the surface, pupae battle their way through the meniscus, and struggle to free themselves from the pupal shuck. This is an epic struggle that can take several minutes, and often times it’s unsuccessful. Large numbers of crippled and stillborn pupae can be found during emergences.
The best emergences of Hydropsyche Caddis occur from mid-June to mid-August in Yellowstone Country. All of our major fisheries have robust populations of Hydropsyche, and fishing the evening emergence and morning egg-laying flights are ingrained in the rich angling history here.
Adult Hydropsyche Caddis spend 2 -3 days resting after emergence before they begin to form mating swarms. Mating flights generally occur well above the water, or around streamside vegetation. It’s not uncommon to see dense clouds of Caddis surrounding riparian willows as the sun gets low in the Western sky and the heat of the day subsides. These massive mating flights generally provide nothing more than a distraction to anglers as the insects seldom touch the water.
Egg-laying females, on the other hand, can be very important. Female Hydropsyche return to the water after mating, and dive to the bottom to lay their eggs. After releasing their eggs, the females drift in the current and slowly ascend back to the surface. There, the egg-layers fight once again to break through the meniscus and make an apparent re-emergence. Spent, egg-laying females then helplessly ride the surface currents. From the time egg-laying Hydropsyche re-enter the water to the time they re-emerge, opportunities abound for trout to prey on them. Egg-laying activity peaks in the morning and evening hours, though females can be seen sporadically throughout the day.