Bitterroot River Fall Fly Fishing

Best Flies For September Fishing In Montana

September fly fishing in Missoula is arguably the best time of year. The water is low, reaching prime temps with longer, cooler nights with the most comfortable wading of the year. The bugs are diverse in size, ranging from size 6 hoppers to size 22 Blue Winged Olives. Subsurface, the nymphing is excellent with so much insect activity, while the streamer fishing comes on as September progresses. It doesn’t matter what type of fly fishing you’re looking for, if you’re in Missoula in September, you’re going to find it. Lets take a look at some of the best flies for September fly fishing in Montana.

Hoppers

September starts with the same flies as you’ve been using since August 10th. The grasshoppers have established, with fish on the prowl looking for a big, easy meal. Missoula hopper fishing starts in late July and depending on weather, may last into November! That’s over 3 months of fish seeing naturals, and their imitations. September is a good time to do a little experimenting with different hopper variations. We carry Pav’s Hopper in 5 different colors, and variations on the Morrish Hopper in 4 different colors. We have gray hoppers, blue hoppers and many pink ones. Why do they work? No idea, but they do. We watch Missoula’s best fly fishing guides shop every morning, and in September they will be looking for full fly bins. The theory is no one is buying them, so the fish haven’t seen too many. Think about expanding your hopper game in September to show the trout

something new and different.

Tricos

The same can be said for Tricos. In early September, you can almost set your watch by the trico hatch. The fish have been looking at naturals for almost a month, and they can get a bit snotty at this time of year. Think about some Trout Hunter tippet in 5.5X. Trout Hunter tippet is much softer than Rio, and allows your bug to float more naturally. The half sizes of tippet provide more stealth without sacrificing as much strength. Move to trico cripples and emergers, like the Sprout or the Quigley Cluster Midge. Ron’s Trico Spinner will produce consistently as well, though by this time of year he is way tired of tying them! Be ready to drop down to a size 20 as well, so make sure you’ve got your readers when you hit the water.

Blue WInged Olives

We’re all waiting for the magic moment in September- the first real rains of fall. If we’re lucky, the rain comes in about September 10th, and the entire complexion of fly fishing in Missoula changes. The weather change brings cooler temps and some clouds. The tricos trade out for Blue Winged Olives. Same size- different color. The week after the rains will prove to any angler that fish can see color! If you fish a trico through a BWO hatch or vice versa, you’re not going to be anywhere near as successful as you could be. Look for the classic figure 8 of a trico spinner cloud above the water, or get your nose close to the water and check what’s floating by. It makes a big difference!

As the BWO’s start, the basic patterns will work. A simple Parachute BWO or Comparadun will take fish consistently at the start of the hatch. But as the BWO’s extend through September, growing in numbers, the fish get a lot more selective. The Last Chance Cripple or Quigley Split Flag Cripple will start to be more effective for fussy trout. Again, shift down with your tippet size to give your fly the best chance at a drag free drift. Watch rise forms very carefully when BWO’s are on the water. Many fish focus on emerging nymphs, and while you’ll see concentric “rise” rings, it’s the fish’s back that breaks the surface, not the mouth. Drop an unweighted Size 18 Pheasant Tail about 4 inches off the back of your dry and watch your catch rate skyrocket.

Mahoganies

In the middle of the month, the Mahoganies start to make their annual appearance. This size 14 mayfly is tough to miss on a Fall afternoon, and provides a steady hatch for the next 3 weeks. The Parachute Pheasant Tail, Purple Haze or Brindle Chute all in size 14-16 are excellent choices at this time, with the Brindle Chute out performing most other flies when the Mahoganies are on, especially on the Bitterroot River where it was invented. Again, as the hatch progresses, start to get a bit more technical with your flies. Bring some Last Chance Cripples or Sparkle Duns when the fish are ignoring your standard fare.

October Caddis

At the end of the month, you can start looking for the October caddis to appear. If you think you can’t miss the Mahoganies, you REALLY can’t miss the October Caddis. This size 8-10 orange caddis is a favorite of fish on the Blackfoot River, Bitterroot River, Rock Creek and the Clark Fork River. If you see one, tie one on. The fish are looking for them and will eat even when the naturals aren’t strong. Both the Orange Elk Hair Caddis and the Orange Goddard Caddis will float a small dropper as well, so make sure to utilize that option as well. The Birds of Prey October Caddis Pupa is deadly subsurface, and if you’re not getting the action you’re looking for on top, get down with the pupa to bring your fish count up.

Nymphs

With all the hatches across Missoula’s rivers, the nymphing can be off the hook! With lower water levels the droppers are shorter and easier to control, especially on the Bitterroot River and Rock Creek. Don’t be afraid to go small. Early in September, the SR Bullet Black in a size 18 is a great trico nymph. When the weather changes the rivers to BWO’s, switch to an SR Bullet Olive and keep raking in the fish. A Pheasant Tail Jig will outperform most anything for the Mahogany nymph, and don’t forget the October Caddis Pupa. It should be said again, if fish aren’t eating on the surface, they’re eating underneath- dry flies get the ink, nymphs get the fish. Especially at the end of the month, when the cold weather tells the fish winter is coming, and they need to eat.

Streamers

The same weather that moves trout to nymph hard also moves fish to eat streamers. When the days start to get cooler and shorter, a great way to start the day is working a small to midsize streamer around the likely areas. If your streamer choice is comfortable to cast on a 5-6 weight, it’s proabably the correct size. This is conventional wisdom, but there are exceptions. In the big water of the lower Clark Fork River and the lower Blackfoot River (which is now bereft of tubers due to the cold) a big streamer run deep will still work its magic. If you’re a streamer-maniac, the last week of September can be prime time, moving bigger fish looking to take in a few calories before the real weather gets here. Pick your spots to run the Mongrel Meat or Sex Dungeons, or go smaller with a Baby Gonga or Dirty Hippie.

Final Thoughts

Whatever you’re looking for when you head to the water, September fly fishing in Missoula has the answer. Whether you want technical dry fly fishing, prospecting with dries, focused Euronymphing, Hopper/dropper or streamer action, somewhere on Missoula’s diverse rivers you’re going to find it. The weather is relatively mild, the wading is easy, the rivers are at good flows and better temps, and you can expect good days on the water. If you live here, carve out some time to fish during some of the year’s best fly fishing in Missoula. If you’re traveling from out of town, get ready to see some of the best fly fishing Missoula has to offer. We’ll see you in the shop, or hear from you online! 

Missoula Montana Guided Fly Fishing Trip

Come enjoy a day on the river with Missoula’s best fly fishing guides. We float the Bitterroot River, Blackfoot River and the Clark Fork River. All gear, lunch and transportation provided.

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Montana Guided Fly Fishing Float Trip
BWO Mayfly

Technical Dry Fly Fishing

. . . . .to fish fine and far off is the first and principal rule for trout angling

                                                                           Charles Cotton  1676

Fishermen were not always so adept at distance casting . . . . they were great skulkers and sneakers.

                                                                           M.R. Montgomery  (from Hooked by Raye Carrington)

Before we go all tech, lets get some basics under our belt. There’s no question that being further away will spook fewer trout. In direct contrast, the longer a cast, the less accuracy and control we have. The art of dry fly angling is finding the happy medium between not spooking the fish, yet having the control and accuracy to place our fly where we need it in a lifelike manner. This comes from practice. You’re going to surprise a few fish as you learn how to get close. We’ve gotten very adept at judging trout size by the V-wake it makes scooting to safety! Like all dry fly fishing, this is the first conundrum to solve. How far is fine, how close is accurate!

You’ve found a pod of fish, 25 strong, and they’re rising! Yay. It’s Ticos and you recognize that! Yay! Yay! And you knot on your favorite Trico and chuck it out there! Boo! Boo! Chuck it and chance it RARELY gets it done! Spend a minute, watch the rise forms. Check out the path the naturals are taking to get a feel for the currents. PICK A FISH. CAST TO THAT FISH. Focus on what you’re doing, and make the first cast count. Chuck and chance has the potential to spook a lot of fish, and put down the pod. Pick a fish on the edge of the pod, and pick that one off first. Then fish your way into the interior of the pod. Think before the excitement takes you.

One more thought on pods of fish. After you’ve been fishing a pod for a bit, you’re going to figure out the fish are pretty focused on one hatch stage. Good on you if you’ve figured it out! But if you haven’t, paying attention to the rise forms will be most important. Look for new entrants into the pod- a rise where there wasn’t one 30 seconds ago. Cast to that fish immediately. That fish has just arrived, and hasn’t had time to get focused on anything too specific. You have a good chance of taking the newcomer before it gets too wrapped up in what all the other fish are focused on.

You’ve made a bunch of casts that you thought were good, but nothing’s taken your fly. The casts weren’t as good as you thought- that’s what the trout have told you! Move your feet. Find a different place to stand. Change your angle and delivery. There is NO SUCH THING as a little drag when it comes to fishing, and even if you can’t see it, the fish can. It’s called micro drag, and it’s a killer. Changing your position will change the drift. Maybe it’s better. If it’s not, move again until you find the place where you can get a drag free drift. You are not a tree- you have feet. Use them!

Sometimes you find yourself in a position where you need a long cast, maybe even 50’. Often there’s some breeze, or other detriments to casting. It’s tough to power out a long cast and have the fly land with slack line. George Harvey designed a leader for this very situation. To build a good replica of this leader, start with a 7.5’ 2X leader. Knot on about 2-3’ of 3X tippet, and then add 3’ of 5X tippet (Adjust tippet and midsection sizes to suit your fly size). What this provides is an energy sink in the middle of your leader. So no matter how much energy you put into your cast to straighten the line, the leader will NOT transfer that energy to the tippet. So your fly, even at a distance, will land with some slack in the tippet, providing a drag free drift at the end of a long cast. You may have to fiddle with tippet and midsection lengths- it’s worth it to get it right and get the drag-free drift.

Where you stand in relation to the fish makes a lot of difference in your presentation. If you’re standing directly below a rising fish, you will be dealing with much less current on your line. It’s easier to control the drag from that position, but easier to line the fish. As you move to a position 90 degrees from the fish, you have greatly lessened the chance of lining the fish, but added so many additional currents you have to fight and adjust to for that drag free drift. Find your happy spot, where you can get to your chosen fish with a minimum of drag without lining the fish, and go from there. Every time you move your feet, you change the effects of the current on your fly. Watch your fly very carefully to see if it’s dragging. If the fish aren’t eating it, it’s probably dragging!

The crafty dry fly angler will sometimes move above the fish, and go for the downstream delivery. This has it’s own set of problems, not least that you’re so much more in the line of sight. The big advantage is the fly gets to the fish before the leader, providing a more lifelike presentation. It also gives you first shot at the fish at the top of the pod, which is often the largest. Again, drag control is paramount. Cast just above your targeted fish, and “check” (stop it somewhat suddenly, above the surface) the cast so it lands with some slack. Allow the fly to float over your intended fish. If it eats, classic angling has you say, “God Save The Queen” before striking. This allows the fly to enter the fishes mouth before striking, and lets the hook actually hook something! When fishing from below or the side, the hook is dragged through the mouth, and hooks as it goes by. From above, the fly will just slide out if you strike too quickly.

If you’re having trouble with upstream presentation accuracy, use the Montana mend. This drives Easterners crazy, but it really works. Cast the fly about 8’ beyond the fish, and then swing your rod upstream, pointed at the horizon or slightly above. When the fly is in line to float in the path you want, quickly lower the rod tip. You may need to add a mend as well.  If the fish doesn’t eat, patience is the name of the game. If you rip the fly off the water to cast again, you stand a good chance of spooking a lot of fish. Let the cast drift out of the pod, as you control the swing with your rod tip. When it’s clear of the risers, then gently, gently start the process again.

You make all these adjustments because you don’t just need a drag free drift, you need an accurate drag free drift. Trout have established feeding lanes, and they’re not going to leave them to provide you with a bit of sport. The feeding lanes will vary by the size of the bug. The green drake, with it’s massive mayfly size, is worth ranging a bit left or right to eat, as the caloric return is worth the extra expenditure of energy. But if you’re fishing tricos, a trout’s feeding lane may be 4” wide. You need to get your fly in the lane before the fish will eat it. With no drag. So accuracy counts. Which is why it often pays to be a great skulker and sneaker!

Drag-free drift. So easy to write, so difficult to achieve! We all talk about mending, but for the wading angler, mending can be difficult. Moving the line on the water near feeding fish can create panic, and ruin the fishing. Knowing the casts that can provide an aerial mend (a mend created in the air prior to the line hitting the water) can be invaluable in dry fly presentation. While many casts exist to provide that, we find you really only need two for 90% of your dry fly situations. The reach cast, which can be done to the left or the right, will place the line on the water either above or below its normal landing spot, providing a mend before the cast has landed. This will take some practice, as you’re working with more line, and the physical reach definitely affects your accuracy.

The other cast we use a lot is the steeple, or puddle cast. Stretch out more line than you need, and throw your cast high above the fish. The cast will straighten, and then fall in a heap above the fish. Yes, wind will really affect how this cast lands. Make too much slack, and the fish might eat and you won’t be able to set the hook. But at least the fish ate, and that’s a start! It’s all about the drift!

We’re saying that again, it’s all about the drift. From the moment you see the first fish rise, you’re on top of your game. Choose your fish, and move your feet to get the correct drift. Move again if it’s not working. Vary your presentation, and use the different casts to get a longer and better drift. Adjust your leader as needed, again to give the fly a drag free drift. Yes, it’s good to read this stuff, and have the intellectual knowledge to hit the stream. Knowing some solutions will really help when the angling gets tricky.

However, there’s nothing like being on water, and  actually practicing these things to make you better. There will be some bumps in the road, no doubt. Which are made much more aggravating, as it looks like every rising fish is giving your fly the fin as it floats (drags!) by. That can scramble your brain! Sometimes, in the heat of the moment, when the fish are ignoring your offerings while rising right next door, it pays to take five. Step back to the bank, or turn so you can’t see the action. Reassess, and pretend it’s happening to your buddy. What would you tell them to do? Chances are the same advice will work for you, if you just take the time to think it through.  Chuck it and Chance it? That’s for the other schlubs. You’re about to start making the smart moves to make you a better dry fly angler.

Insect Biomass

Let’s start out with a few definitions. Insect biomass, for our purposes, is defined as the weight of all insects in a river at any specific time. Carrying capacity is defined as the maximum amount of life that can be sustained in a river system during the harshest conditions. Carrying capacity is always the nadir of population, as the harsh environment removes those less able to adapt to the conditions. That’s enough to be getting on with- more will be forthcoming.

If you look at the graph, there are two pieces of information being tracked. One is the fluctuating aquatic insect population over the course of a year in a river. Overlaid on that is a record of the fluctuating insect biomass over the course of a year in a river. These two pieces of information are critical to understanding the feeding habits of trout in a river.

Let’s follow the line created by the insect biomass in a river. You’ll notice it’s rising in January, and continuing through mid-March, when the insect biomass in the river is at it’s highest. Following the insect population line, you’ll see the insect population in the river is at it’s lowest. Reasoned out, the biomass has peaked because insects have been growing since they hatched, providing more biomass to the river. The insect population is correspondingly low. Few insects are added to the population over the winter, and natural selection and predation has brought the insect population to its lowest point.

And then the first hatches of spring occur. BWO’s, March Browns and Skwalas. As the insects leave the water to reproduce, biomass is depleted. Correspondingly, as the eggs from the spring insects hatch, the insect population begins to rise. However, these new insects are so small, they add little to the biomass of the river, only the population.

As you follow the two informational lines, they diverge until insect populations are at their highest in mid July. Which makes sense, as the bulk of the insects have emerged, and the corresponding eggs have hatched, pushing the population to its zenith. But these newly hatched insects are microscopic, with minimal biomass. By the end of July, the insect biomass in a river is at its lowest point.

These are some of the ramifications of this information. Ever wonder why winter nymphing is so good? With maximum biomass, the trout have access to the most food they will see all year. Jump to July, and the low biomass means food is at its minimum. Combine minimum biomass with the warmer water temps, and you’ve now established the carrying capacity for a river. These are the harshest conditions a river fish faces, and not all fish will survive these critical conditions.

The slash of a fish to a hopper, big fish rising to tiny tricos, the effectiveness of ants and beetles. Behaviors explained by this graph. With such a paucity of food in the river in July and August, fish are willing to be a bit less selective in their eating habits, and range a little farther from feeding lanes to take available food. When a sparkly purple and black thing floats over their heads, there’s a better chance the trout will eat it, because they’re hungrier now than they were in June.

As the natural cycle of insect growth moves on, the biomass of the river begins to recover in late August. Water temperatures drop in September, and the harshest period of the year has passed. The carrying capacity has been established for another year. The insect population will continue to fall, while the biomass rises until we hit March again, and the cycle starts again.

Few anglers use a nymph in a size 18 or 20. Yet this graph clearly shows there are smaller nymphs available throughout the year. As anglers, we get so focused on hatches that we sometimes forget to mimic the most abundant food form, which is small nymphs. The larger trout may not be exactly where you think they should be to take the “prevalent” insect. They may be in a prime location for size 20 nymphs, hoovering up the most abundant food source in the river. Another thought- because many stoneflies are on a two or three year life cycle, stonefly nymphs are always available to the trout. The rubberlegs we all fish so heavily in late spring is still just as effective in the summer and fall, because of the 365 presence of stonefly nymphs.

An understanding of the cycles of food sources in a river can help us understand some fish feeding behavior, and help explain why you can catch huge trout on tiny nymphs. It also may explain the Royal Wulff and Hippie Stomper’s success. Not a truly natural color or shape, but when the fish are hungry, those flies look enough like food to get eaten. Armed with a little knowledge, you may find your catch rate going up in all seasons as you match your tactics to the food source.

Trico Spinner Fly Fishing

The Lowdown on Cripples, Duns, Spinners and Emergers

So much gets written about matching the mayfly hatch. And rightfully so, because when the hatch is at its most intense, the fish are the most focused. They can concentrate on one very particular phase of the hatch, or in one spot on the water column, and if you’re not there, well the trout aren’t going to change their feeding to make you happy!

Trout have an IQ of 4. We use this to set up this example of how a trout feeds during a hatch. Imagine a person with an IQ of 4, standing in front of a conveyor belt, which is bringing things by. Apples, cherries, tomatoes, strawberries, red seedless grapes, raspberries and radishes.  All similar, but different. And all of a sudden, many cherries are coming past and the person at the conveyor belt eats one. It’s good, and they eat again. Imagine the focus needed with a 4 IQ to concentrate on finding cherries. It takes all they’ve got. They lock in, and everything else is out of the picture.

That’s a trout in a feeding lane. They’re on a fly, concentrating for their lives, and nothing is going to break that intensity. As anglers, we might put on a tomato- hey it’s close! But it’s NOT a cherry. It goes by. Same with a raspberry, or cranberry or strawberry. You need to be exact, because the fish isn’t coming out of their little cone of concentration to think of anything else. They don’t have the brain power.

Now, so many cherries are coming down the conveyor belt that some have stems and some don’t. Some are solid red, and some are red/yellow. Again, the person at the conveyor belt gets focused on stems, or no stem, and the feeding process becomes that much more complex. All of a sudden, the person pulling food off the conveyor belt is only eating cherries with no stems that are red/yellow. Yes, there are other cherries going past, but now the focus is tighter, and the food source has become more limited. We think that’s the simplest way to understand what’s occurring during a strong mayfly hatch.

Now let’s get to mayflies. When the blanket hatch is on, like PMD’s, Tricos or Blue Winged Olives, there are many stages of the fly coming past the trout. The fully emerged dun, drying its wings in preparation to fly off. Emergers, which are nymphs breaking their way through the surface film in preparation to become duns. And then there are the cripples. A cripple is a fly that has not successfully made it from emerger to dun. When asked, we say a cripple is simply an emerger that wasn’t capable of becoming a dun. All of these different stages of the same insect are going by at the same time, and like the person at the conveyor belt, the trout will often focus on only one stage.

Quick note. This is most prevalent in a blanket hatch. In contrast, the Green Drakes don’t often come off in huge numbers. They are a sparser emerging insect, and when they come off, there aren’t enough bugs to get the fish focused on one stage. Trout eat the insect that’s going by- dun, emerger or cripple. It takes a lot of bugs to get the fish focused on one stage, and one stage only.

The best guides in Missoula, the best anglers in Missoula and all the shop people will start with a cripple. They often don’t change from that choice, and for very good reason. Nature is a harsh place. If a trout expends 4 calories to move for food, it needs to take in more than 4 calories to survive. We’ve all seen trout come from 5 feet away to eat a hopper. Because the energy expended will be more than replaced with the caloric intake from a hopper. Contrast that with a trico or BWO. Those bugs are tiny, and the reward is much less. A trout will not range far to take in few calories. It’s a fact of nature.

A cripple, to a trout, is a stationary meal. They can’t get away. And that’s critical for a feeding fish. Once the energy is expended, the trout can’t get it back. A cripple is an insect that WILL NOT fly off just at the moment of rising. Again, we’ve all seen fish come out of the water chasing an insect. It’s trying to take in calories to offset the energy expended. It NEEDS the reward at the end of the energy use. Miss that meal too many times, and it starts to die. Not friendly, but true. When an animal is crippled, it becomes easier prey for the predator. Slower to move, easier to eat. Just what every predator is looking for. When there are enough cripples on the water to allow a trout to focus on that phase, they will often do it.

There are more than one type of cripples. You have the failed emerger, caught in its shuck with the wings ¼ to ¾ extended. A cripple may have gotten 10% out of its shuck before failure, or 90%. The wings may be almost fully extended, or maybe just a nub has come out. This is such a boon to the fly fisherman. Once an insect has completely emerged into a dun, they are all exactly alike in size and color (for the most part). But a cripple can vary in length, depending on how far it got in the emerging process. And exact size replication isn’t always as critical with a cripple as it is with a nymph or dun.

The other type of cripple is a mayfly that has emerged, but then ran into problems. Blown over by wind, or simply collapsing onto its side from the energy expended while emerging. Once a mayfly’s wings touch the water, it’s done. They don’t have the strength to pull their wings out of the suction created by the meniscus. Close inspection of the bugs floating by you will sometimes show an insect frantically beating one free wing as the other remains in the surface film. That bug is a cripple, but of the second variety.

An emerger, or a nymph that is breaking through the meniscus, is also exceedingly vulnerable at that time. It takes a moment to get to the surface, push its wings from its thorax through the meniscus, and then crawl out through the hole created to emerge as a dun. It has been likened that a mayfly nymph pushing through the meniscus is akin to a person digging through 3 feet of dirt. Not an easy task. So there are many insects just beneath the surface struggling to get to the surface, and that’s also a stage that a trout will focus on.

Vince Marinaro wrote a book on dry fly fishing called In The Ring Of The Rise. Well worth reading. In that book, he details the different rise forms created by feeding trout. Not every trout that breaks the surface is taking a bug off the surface. That bears repeating. Not every trout that breaks the surface is taking a bug off the surface. In a slow glide, on a still day when the fish are podded up, you can hear the “Chup, Chup, Chup” of fish breaking the surface and taking flies. If you look closely at those rise forms, you will see tiny air bubbles coming from around the take point, A tiny bit of air gets trapped in the trout’s upper jaw, and the bubbles escape when the jaw goes beneath the surface. Chup is the sound it makes.

If only we had a dollar for every time we cast over fish that were breaking the surface but not taking from the surface! We wouldn’t be writing this blog. We’d be retired, and hiring the best guide in Missoula to take us fishing every day!!! When a trout is taking an emerger, it’s eating just below the surface, and its back breaks the water as Mr. Big returns to its feeding station.  And no, the trout is not going to come up that extra half millimeter to make you happy! The best way to handle this is to drop a 6” piece of leader off your dry or cripple, and tie on an unweighted nymph. The short dropper will keep the nymph at the correct depth, and you’ll start to take those “rising” trout. Look for bubbles (or the lack of) to identify those rises.

While we’re on the subject of critically watching rise forms, we’re going to talk about spinners. A spinner is a spent mayfly that has returned to the water to die. The classic form is both wings flat against the water, like a cross, though many spinners will have both wings flat on the same side, and their body curled around their wings. Again, the spinner is a stage of life where it CANNOT escape. The rise form to a spinner is very distinct. It looks as if the trout is coming up and just kissing the surface. Very subtle, very gentle. The PMD’s and Ped’s generate a lot of spinners, and once you’ve started to study rise forms, and see the differences in them, the spinner rise will be quite noticeable. Have some spinners with you, and all of a sudden those fish that went begging are in your net.

Duns. Spinners. Emergers. Cripples. We bandy those terms about like it’s general knowledge, but trust us, that information was hard won. It’s attention to detail that gets you to that point. Learning how trout operate and feed takes time on the water. Watching different rise forms is not easy. It’s tough to take a step back and think when you’re surrounded by trout breaking the surface in a feeding frenzy. But if you take 3 minutes to just look, if you’ve prepared your fly box with the different stages of a mayfly’s life cycle, adding in the failures known as cripples, you’re going to start talking more about how many fish you caught, and less about how many fish were rising!

Best Flies For August Fishing In Montana

When you study rivers and their make-up, you learn the month of August defines a rivers carrying capacity. For our purposes, carrying capacity is defined as the amount of trout biomass, or the total weight of the trout population, a river can support throughout the year. August sets carrying capacity as the most difficult time of year for the trout. Missoula’s freestone rivers- Rock Creek, the Bitterroot River, the Big Blackfoot River and the Clark Fork River– are at their lowest and warmest points in the heat of the summer. Competition for holding lies and food is intense at this time, and fish that can’t locate homes or food won’t make it to the September rains. August is the month when rivers in Missoula make their statement about how the fishing will be for the next 11 months.

This is both good and bad for the angler. Obviously, a scorching August makes trout habitat more difficult to maintain, with trout under considerable stress in Missoula and across Montana. But competition for food and space has a considerable upside for the angler as well. The trout are hungry, and food is scarce. The fish are willing to roam farther from their feeding lies to eat, and certainly less selective. A well presented fly will often take fish even if it’s not an exact match, due to lack of food present in Montana rivers.

Trico

Except for the trico hatch!  The tiny trico is the only aquatic hatch to come off with any regularity in the month of August, and when it comes off, it’s a blanket hatch. Trico-maniacs are dedicated anglers, focused and intense about being on the water when the tricos both hatch and fall. The trico is one of the few mayflies important to the angler that hatches at the same time the spinners fall. It is also the only hatch where the males and females differ significantly in color. For the hatch matching dry fly angler, the trico is paradise masquerading as sheer torment. At any given moment, you have male and female spinners, male and female duns floating as well as male and female cripples on the water. Tricos hatch in such great numbers that the water is covered with insects, with extremely selective to the sex, stage and size of the fly.

No other hatch offers this diversity in fly possibilities. A book has been written about meeting the trico hatch, providing strategies and ideas on how to approach this complex blanket hatch. The most important is make sure you have a wide variety of flies when you go to the water. We know, sounds like thinly veiled sales pitch, but it’s true. Our favorite trico pattern in the shop in the shop is Ron’s Trico. This simple pattern has been a top producer for as many years as Ron Beck, the Missoulian Angler’s longest tenured employee (and dedicated trico-maniac), has been tying them. The Trico Sprout is also an excellent cover for the cripples that are always present, while the Female Comparadun will work as a full floating dry, or as a cripple if you choose to dress only the wings. 5-6X tippet is the norm for these size 18-20 flies, and with the low, clear water a decent cast is imperative. Tiny flies mean narrow feeding lanes, so your cast needs to be on target, drifting correctly and be the stage, sex and size the trout is looking for. As we said, a hatch matchers paradise.

Terrestrials

But it’s not always so tricky in August. The Spruce Moths will be out in full force in the first two weeks, and trout feast on them as they come down to the water. Clocking in at a size 10 or 12, these flies are easy for the trout to find and easy for the angler to see. Again, Ron has created our best Spruce Moth imitation, the Mangler Moth. Made from spun and clipped deer hair, it perfectly mimics the mottled color of the Spruce Moth and floats like a cork. We also really enjoy the Spruce Almighty, with its lower floating profile, and the parachute Spruce Moth, which is the easiest of all our imitations to see. No need for super fine tippet on these guys, 3-4X will get it done when the Sprucies are coming off.

August is terrestrial time in Missoula and throughout Montana. Ants and Beetles are active all day with the heat, and consistently finding their way on to the water. Many times the random rise you see close to the shoreline is to an ant or beetle, and it’s the rare trout that won’t take either if they’re looking up. Again, with less access to food in the rivers, ants and beetles become a critical part of the trout’s diet. The Ant Acid in Purple or Red have proven to be extremely effective, as well as the foam beetle. Take your terrestrial fishing to the next level and try a Sunken Ant along the shoreline. Ants aren’t designed to float, and trout take them anywhere in the water column.

Hoppers also make their grand entrance in August, and we all know what that means. On the hottest, windiest days, the hoppers are up and flying. As the wind buffets them about, they can hit the water with a significant splat, alerting the trout to their presence. Those monster rises mid river in the heat of the day are almost always to a hopper. Because hoppers don’t enter the water with any regularity, you have to be ready on every cast, and ready for some dry spells in between strikes. But the ferocity of the take and the size of the fish that recognize hoppers as a valid food form makes hopper fishing so worthwhile in late August. The Morrish Hopper in all its color variations has proven to be the most consistent hopper we sell. The Parachute Hopper runs a close second, followed by the Henneberry Hopper. When hoppers are on, pretty much any hopper that catches your fancy will catch the trout’s as well.

Nymphs

The phrase originated as Hopper/Dropper, and now morphed into Dry/Dropper. But the original indicator fly was the hopper, because the nymph fishing in August can be great. The fish are looking to feed, stay out of the sun and away from the surface where they’re vulnerable. You can use pretty much any nymph in your box (within reason!) but we definitely prefer the Tungsten Bead Jig Nymphs. They sink like bricks, ride hook point up to snag less, and get to where trout live and stay there. Exactly what you’re looking for in a subsurface fly! Don’t be afraid to go with a size 16 or 18 nymph. The river is filled with smaller nymphs, and while they don’t look like much to you, the trout are accustomed to these smaller flies and take them without hesitation.

Streamers

A quick word about streamers. The dedicated streamer angler has put away the 7wt rod. The giant streamers, so effective in June, are too big to effectively fish in August water But trout haven’t stopped eating minnows. Scale back your fly’s size, and the bruisers will prove just as happy to eat a big meal in August as they were 6 weeks ago. Look for a slim, smaller fly like the Sculpzilla, the Kreelix or even the Baby Gonga. If you can throw the streamer comfortably on your 5 weight rod, you’ve scaled back enough. The smaller streamers make less commotion when they land, and in clear water present a less more lifelike appearance than their larger brethren. Predators are predators, and few turn down a well presented, easily captured meal!

Attractor Patterns

August is the fly tyer’s month as well. Remember that fly you tied late at night, purple, chartreuse and orange. You looked at it the next morning and thought, “What was I thinking?!” August is the time to fish that fly, and any other attractor that strikes your fancy. Food is scarce, and trout are willing to be more liberal about what constitutes food and what doesn’t. August is when oddball flies really shine. The trout are heavily fished late June and July, and very familiar with tried and true patterns. Show them something they’re never seen, like your late-night concoction, and you’ll be surprised by the gullibility of August trout.

Final Thoughts

August is a month where getting on the water can be a challenge. Heat, low clear water and the concern for the trout’s well being all come into play. But it can be a great month to angle. Fish the edges of the day if you can, and when we say edges we MEAN edges! If you’ve never tried mousing after dark, August is the perfect time to make that plunge. The weather is grand, with big fish responding to lower light and lower water temperatures. Flashlights and a little pre-scouting are certainly not remiss if you plan to be out after dark. And this is information you won’t get many other places, because we’re more about real fishing! If you fall in after dark in August, it’s not as cold as the other months!! If you are fishing mid-day with a hopper, fight the fish hard and fast, releasing them in cold water so they live to fight another day. August gets a bum rap from so many anglers, but if you put your time in, find the trico hatch, come prepared with hoppers, nymphs and streamers, you’ll find August to be an exceptionally rewarding time to be on the water.

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Mahogany Nymph

Low Water Nymphing

In the low, clear water of summer, many anglers really focus on the surface action. Less water means less current, making a rise much more energy efficient. The fish are in clearly defined areas, and easy to prospect for. Clear water makes the dry fly appealing, and many anglers ply the surface all day, hoping for the slash to a hopper, spying the subtle sip of an ant or the plop of a beetle. Waning PMD’s, Tan Caddis and PED’s can keep your focus on top, but you’re missing out on where feeding fish are most of the time! Trout don’t like the sun- it hurts their eyes and makes them easy targets for predators. They want the bottom when the water is clear.

You see a single rise, and the adrenaline rushes. Rising fish! You stare at the rings, and wait for another rise, but it’s not happening. Missoula’s best fly fishing guides call this one and done. Whatever that fish came to the surface for, it seems to be a one off. No reason to stay and wait for another rise- it’s going to take a while to bring that fish back to the surface.

But you’ve learned something. There’s a hungry trout in that spot. An old phrase comes to mind, fish where the fish are! That fish has alerted you to its presence, and willingness to feed. Set yourself up with a nymph, and go after that hungry fish. The hard part is done. You know where it is, and know it’s feeding. Take advantage of what the trout tells you.

Low water nymphing can be as easy as rigging up a dry/dropper rig. Pick a high floating fly and tie it on the end of your leader. Check the depth of the holding water for your chosen fish, and use 1.5 times the depth as your dropper length. If you think the water is 2 feet deep, make sure your dropper is attached to three feet of leader. We strongly recommend fluorocarbon tippet for multiple reasons. It’s much denser than standard tippet, so it sinks faster. It’s as close to invisible underwater as you can get, and it’s extremely abrasion resistant. That’s important because banging the bottom with light tippet weakens its strength. We also recommend going with the lightest indicator you’re comfortable with. Additionally, if you’ve been fishing dries on a 12 foot leader, cut your leader back a bit to control your rig. Accuracy is critical, and if you’ve built a 16 foot leader with two flies on it, it can get pretty unwieldy.

There’s a huge difference in dry/dropper fishing, depending if you’re in a boat or wading. When floating, you’re less worried about landing the fly in the water, and more worried about the floatation of the dry. With good mending, you may get a 100 yard drift from a boat, and your dry fly needs to have sufficient buoyancy to handle repeated mends. The Morrish Hopper, Plan B or Chubby Chernobyl provide exceptional floatation, recovering from the mend and resurfacing to maintain your drift.

There are two distinct ways to low water nymph for the wade fisherman. The first is to go dry/dropper, or run an indicator and two nymphs. Using a high floating fly/indicator, the angler casts to likely water, mending as needed. The indicator returns to the surface when mended, keeping the nymph at the depth set by the angler. Fish the likely spots, just as if you were in a boat, with vigorous mends, using the floatation in your fly or indicator to bring it back to the surface after mending.

This may not be the approach to use when targeting a specific fish, like our friend that went one and done 4 paragraphs ago. Often, the larger dry or indicator will create quite a disturbance when it lands on the water, alerting the fish to your presence. For targeted nymphing, use a very light indicator, like New Zealand Wool or Palsa indicators, or a fly like the Royal Wulff. The reasoning goes this way. A wading angler is lucky to get a 3 second drift. Try it sometime. Cast your dry out and count how long it floats before dragging. You’re going to find that 3 seconds is long! Aerial mends, like the reach cast or steeple cast, are critical for the wading angler’s arsenal, extending your drift to the 3 second mark!  

You’re using the Wulff as an indicator, not really as a fly. The water is low and clear. The targeted nymph fisherman may tie a size 14 Tungsten Bead Head Jig to a size 12 dry. No, it’s not going to float your nymph very well! But that’s not the point. Your fly is an indicator, and in clear water, it’s visible even if it sinks. React to any movement in your point fly, whether floating or drowned, just as if it was on the surface. The light touch won’t spook your fish, and as long as you can see your “dry” in the water column, it’s still your indicator. Stealth is the name of the game in low water. A light indicator fly might not control depth like an Airlock, but still tells you when your nymph has been eaten.

Back in the dawn of fly fishing, like pre 1970’s!, nymph fishermen fished without indicators. I know!!! It seems crazy in this day and age, but nymph fishers didn’t use an indicator. They watched for subtle movements in their leader or line tip to alert them to the “quick brown wink underwater.” Believe me, they would have used them if they could have, but they weren’t available. The first indicators were made of fluorescent orange fly line peeled from the core, and they revolutionized nymphing. They were a pain in the tuckus to use, but they made all the difference.

Yesterdays nympher would quickly recognize Euronymphing today. The old timers “high stick”, now we euro nymph. Using a long rod often extended way above shoulder height, euro nymphers keep as much line off the water as possible, controlling depth and drift with the tip of the rod. They work the best water, and after a few careful drifts, can have the fly dancing along the bottom, adjusting for structure, current speed and depth. It’s amazing to watch a good euro nympher at work- they will take fish all day long, because they’re where the fish are at all times. Euro nymphers use a variation of the lightweight indicator, and will use it on the surface or submerged if necessary to get the proper drift.

Which brings us to THE MOST DIFFICULT Missoula trout fishing you can find- sight nymphing. Lets start at the beginning. You need to be on your game enough to spot a feeding fish underwater. No gimmes here, like concentric rings of a rise. You need to spot the fish before you spook it. Then ascertain how deep the fish is, and find the best position for your presentation. You need to know exactly how fast your nymph sinks, how fast the current is moving, and then gage your cast to get the nymph to the proper depth, at the proper time in the correct feeding lane. With no drag. After that, it’s a piece of cake . . . unless the trout is focused on a specific nymph, and then you have to figure that out as well. Many sight nymphers wil pre-scout an area for feeding fish, just as a hatch matcher will find where the fish are rising. It takes some of the guesswork out of the process.

Sight nymphing makes dry fly fishing look like spinfishing. It’s a 3-D presentation to fish in clear water, with all that entails. On the Henry’s Fork, anglers often work in pairs, one on a bluff watching the trout while the other is in the water casting. The spotter relays if the drift was good, if the fish moved and any other pertinent data. We’ve not seen that done in Missoula, but there are places on the Clark Fork River, Blackfoot River and the lower Bitterroot River where that approach would work. If you’re hanging around the shop, and someone says they’ve taken some fish while sight nymphing, it will pay to eavesdrop on their conversation. You’re probably going to learn something! Do it with stealth though, just like nymph fishing in the low, clear water of summer and fall!