Welcome to Not Quite Entomology

Welcome to Not Quite Entomology! This is a different approach to matching the hatch, or learning which insect the fish are really eating. The flies and methods to make it all work will be here as well. We hope this series will inspire you to go out, look on top of and under rocks, check the stream-side vegetation, really investigate your favorite water and learn which are your local trout's favorite foods!


More Midges - Diptera

By Jeremy Barela


With the heart of winter at our doorsteps, many fly fishers are counting down the days until they can get out and wet a line again, while others are fishing the one bug that hatches year round, the mighty midge.

Fishing the San Juan River, I have learned just how important midge patterns can be. Midges are the main staple on this and many other rivers, especially during the winter season in the southwest. Midges can be identified by one distinct feature - the fact that they have two wings. These "true flies" belong to the order Diptera, family Chironomidae.

While doing research for this article, I found that a majority of the rivers I read about have some form of midge hatching throughout the year. From the Yakima River in Washington to the Yellow Breeches Creek in Pennsylvania, midges are an abundant source of food giving trout thousands of opportunities to eat during the day.

The simplest way to find out whether midges are hatching in your home waters is to look. This can be done in many ways; a panty hose sock over your hand, some type of seine whether it be home made or purchased from a shop, or just turning over a rock. Another way of determining what is in the river is pumping a trout's stomach, but I do not recommend this method, as it can be harmful to the fish. However, by looking for this tiny bug, you can only help increase your catch rate.

The first place to look for midges is near the riverbed, where most fish are found feeding during the beginning and end of the day, or in between hatches. With no prominent hatch occurring, trout are feeding on what is most available to them.

Once an adult lays the eggs in the water, the first stage this bug can be found in is the larval form. Once they have been dislodged from the riverbed, they wiggle frantically in the current, making them an easy meal for the trout. The most effective way of fishing this stage is to use some type of weight 12-18" from your flies, helping you get your flies in the area the fish are feeding. Although this may sound easy to do, on the San Juan River, it is vital to find the exact depth the fish are feeding. Because midges are so abundant, if you do not get your flies directly in the feeding lane, you will not have much success. Trout do not expend much energy to feed on midges because more are right behind and will be much easier to eat.

Larvae can be found in various colors as well, with red being the most productive pattern I have fished. The other colors include gray, olive, cream, black and gray with a slight segmentation also present. The sizes of these range from 4-15mm (#16-26 hook size) and are also very thin. A great imitation of this pattern is the simple Red Thread Larva.

After the larval stage is complete, midges then enter the pupal stage, where tiny air bubbles are trapped in the body of the insect and help them slowly rise to the surface. Because they rise slowly, this makes them available to feeding trout once again. It may take a few tries to reach the surface, as the pupa form can bob in the current until completely riding just underneath the surface where they wait to emerge as an adult. Fishing this stage of the midge can be done in various ways; weight can be used to place the fly in a certain area, or you can fish it just underneath the surface as a trailer from an adult form.

Like the larvae form, pupae can be found in various colors such as brown, black, gray, olive and cream. There is also a slight segmentation, but the distinct difference is the prominent thorax that has formed, giving the bug a tapered look. Many pupae also go through a complete color change during this stage. Pupae are often shorter and a bit thicker, being found in sizes 4-12 mm (#18-26 hook size). Imitations for this stage of the life cycle can be a miracle midge, black beauty or trojan midge.

The next stage is in between the pupal and adult stage, which is the emergence. This is not actually a classified stage in the life cycle, but when fishing I consider it one of the most important and key times to fish the midge. Once the pupae begin their emergence from the riverbed, they shed the shuck or tube they have been developing in and ride in the surface film waiting for their wings to dry. In my opinion, because they are so vulnerable at this stage, fish key in on this stage more than any other during the peak of a hatch. You can see trout breaking the surface with their dorsal fin as they cruise along sipping on the thousands of emerging midges trapped in the surface film.

The same colors found in the larval and pupal stage can also be found in this stage. And like the pupal form, the thorax can still be prominent and a trailing shuck, segmentation and wings or gas bubble can also be found. The size is also similar to the pupal stage, with most bugs being in the 4-12 mm range (#18-26 hook size). The pattern I like to use to imitate this stage is a zebra midge with a trailing shuck made from grizzly hackle fibers to give the appearance of a segmented shuck. This can be fished with weight to simulate the rise to the surface, with a greased leader to keep the fly right at the surface, or trailing a larger adult pattern as a dry-dropper. One other way of fishing this pattern is by letting the fly swing at the end of a dead drift, to also imitate the emergence of the bug. Other popular emerger patterns that produce well are the Johnny Flash, foam-wing emerger and WD-40.

The final stage of the midge life cycle is the adult stage, where six legs have formed along with the two wings. Once the midge has left the water, their main goal is to mate and return to the water where they will deposit their eggs. Because they return to the water, they become vulnerable once again to fish feeding on adults. Another reason trout key in on this stage is because midges are found in clusters, which makes for an easy meal.

Like the other stages, adults are also found in the same colors (black, brown, gray, olive and cream) and range in size from 4-12 mm (#18-26 hook size). Adults are fished like any other dry fly pattern, but the most productive method is to cast to rising fish after timing each rise. Patterns I like to use to imitate the adult stage are cluster midges or griffith's gnats as well as biot midge adults.

Although it is fun to fish the adult stage, I always trail some type of emerging midge behind an adult to increase my chance of hooking into a trout.

Even though I have named a few patterns for each stage, there are thousands more that can be fished in the same manner that will help you catch picky trout on many waters throughout the U.S. Searching the internet for midges is as simple as looking for them on the waters you fish. A few sites I always like to turn to for such patterns are, www.ifly4trout.com www.danica.com/flytier/ as well as many others.

A great book that has many patterns with simple tying techniques is Don Holbrook and Ed Koch's Midge Magic. But the best way for you to find what midge patterns will work best on your home waters is to get your hands wet and play with the bugs! ~ Jeremy

Credits: Photos of the real insects were taken by Mike Mora of www.ifly4trout.com.

For more on Midges see: Midges - Diptera


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