Matching the Hatch: Midges

Matching the Hatch: Midges

May 28, 2014 2:11 pm Published by Leave your thoughts

Stomach sample full of midges

Midge Hatches on the Bighorn

Here on the Bighorn the midge is the first significant emergence of the year and accounts for the first opportunity for anglers to find consistent dry fly fishing. Along with increased surface activity, anglers can find trout more actively feeding sub-surface on midge larva and pupa.

Midges go through a process of complete metamorphosis, similar to that of the caddis species. Successful Bighorn anglers will fully understand the larva, pupa and adult stages of this emergence and the fly patterns that imitate each of them.  Anyone fishing the Bighorn in the winter and spring should have sound knowledge on every aspect of this emergence.

Hatch Times

Midges are one of the most prolific aquatic insects found in the Bighorn River. While available to the trout year round,  midges are of the most importance to the angler in late winter and spring. Daily emergences occur from February through May depending upon water temperatures. Single midges typically begin emerging early to mid morning. By late morning into the early afternoon mating midges will begin to form midge clusters on the surface of the water.  Midging fish can be found well into the evening during the heavies hatches.  Many times these midge emergences will coincide with Blue Winged Olive emergences here on the Bighorn. At times you may find yourself fishing a BWO pattern in tandem with a Midge imitation.

Midge Size and Color

Here on the Bighorn Midges can range in size from 16 – 24, giving angler’s reason to both love and fear them. Earlier in the emergence you will find them in larger sizes. As the emergence peaks in intensity, the size of the insect typically starts to diminish. Regardless of the size of the insect present, trout will selectively feed on any one size and/or color at any give time. Be prepared with an assortment of patterns in a wide variety of sizes and colors for each stage of the emergence. Throughout this size range – 16 – 24, midges can be found in a variety of colors such as black, red, olive, cream and root beer.

Stages of Emergence

Assorted Midge Larva

Assorted Midge Larva

Larva: The larva is the first stage of the midge emergence and available for trout year round. The larva have tube like bodies that feature pronounced segmentation that your imitations should represent. Here on the Bighorn the midge larva is fished religiously behind either a scud, sowbug, or worm. When taking either a stomach or seine sample, you will notice that the midge larva will appear in a variety of colors. Fishing the right color at the right time is crucial to success. This is where a stomach pump is very useful.

Best Midge Larva Patterns:

Zebra Midge – Black, Red – This old standby is a must have on the ‘horn
Dill’s Cream Midge
Red Stretch Tube Larva – When red larva are present this is the fly to have
Black Beauty
Yong Midge

Midge Pupa

Midge Pupa

Midge Pupa: When the midge larvae reach maturity they will form wing buds and turn into midge pupa. The newly formed wing buds trap gas bubbles that aid the pupa in ascending to the surface. The trout key in on these ascending pupa most often, making the pupa stage of vital importance to nymph fisherman. Midge pupa range in a variety of different colors, similar to those found in the larva stage. Colors such as black, brown, and olive are common on many patterns that we fish here on the Bighorn.Once reaching the surface, Pupa at times can struggle to break free through the surface film because of their small size leaving themselves subject to an easy meal by eagerly waiting trout. Bighorn trout key in on emerging pupa below the surface film. Fishing a midge pupa 10 to 12 inches behind an adult is an effective method, and imitates the midge in the surface film rather well.

Best Midge Pupa Patterns:

Rootbeer Midge – A must have for fishing the Bighorn in spring
Juju Midge
Jailbird Midge
Copper Ribbed RS-2


Midge Adult

Midge Adult: While small in size the intensity of midge emergences on the Bighorn bring trout to the surface eagerly making for exciting dry fly fishing . Sizes 18 – 22 dry flies can put fear into many anglers, but midge fishing makes for a fun and challenging day on the water. The adults will emerge in soft water such as seams and long flats, often becoming heavily concentrated. When the time comes for the males and females to mate they do so on the surface of the water, often skittering and tumbling across the surface. At this time you will find trout slashing on the surface to nab these insects. Fishing midge cluster imitations provides great opportunity for the angler.

When fishing Midges it is not uncommon to have a tandem dry fly setup, with either a midge cluster or baetis pattern as the lead fly, to help you better see your flies on the water. Often the most effective midge imitations sit low in the water and are difficult to see. The key to being successful fishing midges on the surface is being an accurate caster. Unless trout are slashing to those clusters they usually feed in rhythm in one spot.

Best Midge Adult Patterns:

Parachute Adams
CDC Transitional Midge
Skittering Midge
Griffith’s Gnat
Twilight Midge



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This post was written by Bighornangler

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