How do you decide what fly to use? In the past, choosing which fly to tie on always presented me with a quandary. I would fill my fly boxes to overflowing with flies of every size, color, pattern and shape and tie on whatever fly previously had been effective. Then, after hours of pounding the water and not getting hit, I would randomly select another fly and try again. If I was lucky enough to be with buddies who were landing fish, I’d ask what they were using and switch to that fly. Sound familiar?
Back then, fly selection was confusing and seemingly dictated by an indecipherable number of variables. When I wasn’t getting hit, I would sometimes empty my entire fly box switching flies trying to discover which fly worked the best. While fishing with Denny Rickards, he would tell me that he lets the fish dictate what fly to use. How to do this initially eluded me. Over the years, I dedicated myself to the quest for understanding why and when to use which fly.
Now my fishing buddies ask me what fly I have on. I let them know and provide them with samples of the fly while silently reminding myself, “this is what the fish told me they wanted.” To know how to do this, you must understand the relationship between the trout’s feeding behavior and the conditions. Gaining this knowledge peels back the layers of mystery in fly selection, and its lessons are applicable to any lake whether you are using dry flies, nymphs or streamers.
Is it important to match the hatch? Fly fishing anglers have long followed the tradition of matching the hatch, especially while fishing rivers. However, in stillwater environments, it has been my experience that when fishing dry flies, the fly does not have to be an exact imitation of the natural. I have found that an approximate representation of the natural is sufficient in size, color and shape. Size is the most critical element, because if the size of the fly does not approximate the natural, it will likely be refused.
When trout are selectively feeding on the adult stage, they will not take time to stop and evaluate whether the fly is an exactly match to the natural food source. If the fly looks like food and behaves like food, trout will eat it.
When trout are focused on the adult stage of the insect, insects in the nymph stage will go unnoticed. The only time during a hatch that I have found that trout take a nymph is just before and near the end of a hatch. I experienced this just before an epic mayfly hatch while fishing a lake in Wyoming.
Using my callibaetis nymph patterns, I had just landed an 18-inch trout. The bite stopped as soon as the mayfly hatch started. Using an Adams dry fly pattern, I hooked a fish on every cast. This lasted 10 minutes and I landed three 20-inch trout. The feeding frenzy was cut short when windy conditions forced the adult insects off the water. Immediately, the trout stopped feeding on the Adams dry fly, but were lured again when presented with the nymph pattern.
Since ninety percent of the time trout feed below the surface, it becomes a dilemma to know which insect stage of development the trout are feeding on. For example, take standard patterns like the prince nymph, pheasant tail, hare’s ear and zug bug – all nymph flies used for years. The reason they work is because these are all patterns which suggest various aquatic insects in pupae form. (midges, caddis, mayfly and damsels). It is not the insect, but the stage of the insect that our flies imitate.
If the fly imitates the natural undulation and movement of an aquatic insect, the trout will see it as food and react. Whether it is a chironomid, streamer or aquatic insect, it is the movement of the fly that triggers the response.
How do you determine whether to use a chironomid, streamer or aquatic insect pattern? The answer to this is based on several factors. I will cover three: water conditions, time of year and time of day.
A. Match the fly to conditions
Keeping an eye on barometric pressure trends is important as it indicates changing weather conditions. Weather factors like rain, wind, sun, and temperature impact conditions under the water and subsequently affect the trout’s feeding behavior. When conditions change, changing flies may be indicated.
Prior to a change in weather conditions, trout seem to sense a change. For example, while fishing Crittenden Lake in Nevada, before an incoming storm arrived, the trout started feeding more aggressively. Using a grey callibaetis, I successfully landed several 20-inch trout. When strong winds arrived, the bite fell off. I switched from a small aquatic fly to a seal bugger because the seal bugger, when retrieved, creates an undulating movement. The movement of the fly grabbed the attention of two more trout I was able to land.
A change in weather conditions impacts water conditions and subsequently affects the feeding behavior of trout. The following guidelines outline how to select the fly relative to weather conditions.
Cloudy Skies – If trout are making surface rings, use small aquatic patterns (e.g. the stillwater nymph or callibaetis nymph).
If there is no visual surface activity, use suggestive flies like a seal bugger.
Trout perceive that it is safer to move out of their protective cover to feed under cloudy conditions.
Windy with incoming clouds – Surface ripple will also provide protective cover so trout feel safer to feed. Use small aquatic flies like the stillwater nymph. Active feeding behavior can precede an incoming front, and in many cases, the bite will briefly accelerate.
Cloudy and stormy – Midges, seal buggers or stillwater bugs are effective when probing the depth where the trout may be feeding. Fish with darker colored flies in the top 10 feet. Clouds, wind, precipitation and abrupt temperature changes, which are consistent with low pressure, will cause trout to seek cover in deeper water and/or underwater structure and become less active. A consistently falling barometric pressure may indicate that a storm is coming. Once the barometer falls below 29.9 inches, you might as well go back to your fly tying bench because trout will go off the bite until the storm front subsides and the barometric pressure starts climbing.
Mostly clear skies – If there is surface activity, select emerger patters like the A.P. emerger, midge pupae, or other small aquatic flies, and fish in the top 2-3 feet. Trout will resume feeding in the shallow between weedy areas or shoreline areas.
Clear – Use your favorite bright flies because the bite will return to normal when the weather is recovering from a low barometer and the fish have had a chance to stabilize after a day or two. Fish the shoreline areas early and late with suggestive flies. Use your favorite pupae patterns when fishing in the top few feet.
B. Match the fly to the time of year
Fly selection must also factor in the time of year, because the time of year determines what food will be available.
In early spring or late fall, when the water is cool and aquatic food sources are scarce, chironomids and seal buggers are productive.
Summer, when the water temperature increases and aquatic insects begin to emerge, use impressionistic patterns of aquatic insects. If you see shucks in the water you know that there has been a recent hatch. It is a good place to start fishing pupae nymph patterns.
During the fall, I decrease the size of the fly because insects during that this time of year are smaller. Larger flies that worked well in the spring may now scare away fish in low, clear water.
During the winter months, due to the colder water, midges and seal buggers fished near the bottom may entice reticent, dormant trout into a reactive bite.
C. Match the fly to the time of day
Early morning before the sun is on the water and well as late in the day, seal bugger, minnow or leech patterns are productive enticing big trout cruising the shallow shoreline edges with the promise of tasty morsels of protein.
In lakes with silt bottoms, weed beds and shallow shoreline edges, hatches start mid-morning as the water temperature warms. When this occurs, I change my fly to an emerger aquatic pattern like an A.P. or callibaetis nymph.
Midday when there is high sun, trout are more reticent to come out of their protective cover to feed. This was illustrated when my fishing buddy and I were fishing a lake in Central Oregon during a clear summer day. The day was sunny with just a slight ripple on the water. Water temperature was 56 degrees in the channel. We both fished the same shoreline, the same pattern (an orange stillwater nymph), and the same retrieve and line. However, he was successful in landing three brown trout, while I did not even get a nibble.
The reason why was due to the time of day. I fished the channel three hours earlier when the sun was high in the sky. He fished the channel late afternoon, when the sun was low. The lower light conditions later in the day enticed the browns to move out into shallow shoreline areas to feed.
When do you change the fly?
If you are doing everything possible and still not getting hit, when do you change the fly? If you face any of the aspects included in what I call the “trifecta of doom” which is a north wind, low pressure, or a full moon, changing the fly will not make a difference. Trout will stay sheltered and uninterested in eating until conditions change. Under such conditions, go visit a favorite restaurant or attack your honey-do list until conditions improve.
However, when you are not dealing with any of these factors, and repeated attempts pounding the water have not yielded a hook up, one or more of the following situations usually exist:
- There are no fish where you are fishing – Not getting hit is likely the indication of the absence of feeding trout. The solution is, when the bite slows, move to other areas where trout may be feeding. Fish continually move, and so should you.
- There may be fish, but the cast may have spooked the trout. Cast in a different spot, never recast in the same area, because fish will move away due to the disturbance in the water.
- You may be fishing at the wrong depth. Your fly may be moving at a depth of 6 feet, but the fish are feeding at two feet. Try probing different depths.
- You know the fish saw the fly but refused it: If you are getting repeated bumps and touches, but no takes, then you know the trout have seen the fly, but rejected it. I first change the size or the color before I change the pattern.
Remember it is not the insect, but the stage of the insect that our flies imitate. The reason that various patterns all work is that they represent various aquatic insects in pupae form.
Be aware of the current conditions, time of year and time of day, and evaluate how it will affect the feeding behavior of trout before you make your fly selection.
A fly that worked yesterday may not work today due to changes in the trout’s feeding behavior as a result of changes in their environment. Be willing to adjust your fly selection accordingly.
Change the size or the color before you change the pattern when you know that trout have seen but have refused the fly.
If not getting hit, try fishing different depths, move to another location, and avoid repeated casting into the same area before you change the fly.
Note: If there are any questions that you would like me to answer, please send them to me using the contact form. I would be delighted to hear from you.