Short answer: midges are tiny two-winged insects, usually size 20 or smaller, with wings that lie flat over the back and long feathery antennae on males. They hatch year-round, which makes them the most reliable food source on most trout water — and the one worth learning to identify first.

Anglers often talk about matching the hatch. Among the myriad of insects that can have you scrambling for your fly box, the midge holds a special place. Tiny yet significant, identifying midges and their hatches can improve your fishing immensely.

That said, there are elements of a match-the-hatch formula I've coined that matter more than the fly itself. Two are absolutes and the others are decision-making guidelines: Observation and Presentation are paramount; Silhouette, Size, and Color are guidelines. In this guide I'll unravel the mysteries of the midge by giving you identification characteristics you can combine with the OSSCP formula.

For most waters the midge is a reliable food source all year round, and identifying one and its hatch can significantly change your fishing.

How do you identify a midge fly?

Midges are often mistaken for mosquitoes. To identify them accurately, look for the following:

1. Size. Adult midges are small, ranging from 1/16" to 1" in length — generally size 20 or smaller.
2. Wings. Unlike mosquitoes, midges have two equally sized wings that lie flat over their backs. Look for this distinguishing characteristic.
3. Antennae. Long, feather-like antennae, especially in males.
4. Body. A slender body, sometimes segmented, with colors ranging from black, brown, red, green, to cream.

The midge life cycle

Knowing the life cycle ensures you choose the right fly. This is especially important when a particular stage is what the fish are keyed on.

1. Egg. Laid in gelatinous masses on the water surface, often sinking to the bottom.
2. Larva. Resides in the substrate, feeding and growing until ready to pupate.
3. Pupa. The transitional stage, where they ascend to the surface, often visible due to their sheen.
4. Adult. Emerges from the pupal shuck, floats on the water, mates, and lays eggs.

Technical background

1. Species. Chironomus plumosus is a common midge. Its larvae are red due to hemoglobin, which gives them the name "bloodworms." For that reason, red is a common midge color to start with.
2. Preferred habitat. Midges thrive in slow-moving or still water. Areas with lush aquatic vegetation are often teeming with midge larvae.
3. Dietary behavior. Midges are filter feeders in their larval stage, feeding on microscopic algae and bacteria.

Signs of a midge hatch

Midge hatches can be goldmines if you know the signs.

1. Time. Predominantly during colder months, but midges can surprise you year-round.
2. Hatching clusters. Spot tiny insects dancing over the water? You're likely witnessing a midge hatch.
3. Surface indicators. Floating shuck piles, or shed pupal casings, hint at midge activity below.
4. Bird behavior. Swallows skimming the water are a natural alert system for a hatch in progress.

What to observe on the water

1. Rising fish. Trout breaking the surface, consuming emerging midges, is the clearest indicator.
2. Floating adults. Adults on the surface after mating is another sign of an ongoing hatch.
3. Bird activity. Birds actively feeding above the water.
4. Silvery shine. Underwater, midge pupae reflect light and give a silvery shine as they emerge.

One important caveat: seeing midges on the water regularly doesn't mean fish are feeding on them, or that the hatch is significant enough to drive trout feeding behavior. Observation of the fish matters more than observation of the insects.

Midge patterns to carry

Because of their size, flies imitating midges generally run between size 18 and 26. Match size, silhouette, and color — in that order.

Nymphs and larva

The Zebra Midge is the workhorse and it's worth carrying in more than one color, since bloodworm larvae skew red while emerging pupae often read darker. We stock the Red Zebra Midge Assortment, the Black Zebra Midge Assortment, and the Olive Zebra Midge Assortment, each with three flies in each of sizes 14, 16, and 18.

If you fish midges hard, the Black Zebra Midge dozen assortment is the better value, and single sizes are available if you know exactly what your water wants.

Emergers and attractors

The Bead Head Rainbow Warrior Midge Assortment uses a silver bead that plays directly on that silvery pupal sheen described above — a genuinely good match for the emergence stage. When fish are eating right in the film instead of below it, the CDC Midge Wing Emerger is the one, and the Midge Subsurface BugCycle carries the larva and pupa stages together on barbless hooks.

If you want one box that covers it

The Basics Collection Essential Bead Head Midge Nymph Assortment gives you 10 flies across 5 patterns in sizes 14, 16, and 18. That's the simplest way to have the whole category covered.

Fishing a tailwater in winter? Midges are frequently the only game in town, and these are the flies for it. Browse the full fly patterns collection and assortments. Because you're fishing small flies on fine tippet, stock up on 5X tippet and see all tippets.

Fishing the right stage

When fishing, consider the prevalent life stage in the water. If pupae are ascending, an emerger pattern will be effective. If trout are sipping quietly with barely a ring, they're often taking adults or stuck-in-the-shuck emergers right in the film rather than on top of it — and that's the moment most anglers keep casting a high-floating dry and wonder why they're refused.

Correctly identifying midges and their hatch is a skill that separates novice anglers from seasoned ones. By paying attention to the midge's distinct characteristics, observing the environment, understanding its life cycle, and applying technical knowledge, you can significantly improve your fishing.

Ready to put it into practice? Read the Formula for Systematizing Your Cast for a Perfect Drift — with flies this small, presentation is nearly everything.

More hatches: the Blue Winged Olive, the caddis, and the mayfly hatch.

By Christian Bacasa
Host of the Fly Fishing Insider Podcast
ffipodcast.com
@flyfishinginsiderpodcast
@dupeafish
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