Winter Midges

By Jeff Morgan

As a mild November turns into a frigid December, the idea of rising trout is something most anglers tuck into the back of their mind until spring . . . or at least until after the Super Bowl. Days are filled with holiday shopping, football bowls, holiday parties, and--if there is time to chase lethargic trout--lots and lots of indicator nymphing.

We all have our favorite winter indicator rigs. Mine is a Pupatator and a small cream egg, to match the abundant whitefish spawn of the season. Other anglers like the trusty Prince and a tiny Pheasant Tail dropper. Following a winter rainstorm, some will tie on one of the most loved, loathed, and at times deadly flies, the San Juan Worm .

If you checked the stomach contents of a few dozen fish during the winter months, you would certainly find some of those eggs, aquatic worms, blue-winged olive nymphs and cased caddis larvae in stomach samples. However, day-in, day-out the midge is by far the most numerically dominant food for winter trout.

Like the word "Spey," the word "midge" is a term fraught with assumptions for the angler. Many people hear "midge" and tense up, fearing the inevitable difficulties threading gossamer 7X tippet through the tiny eye of a size 22, 24, or (gulp) even a size 26 black pattern that would be impossible to see on the surface anyhow. While effective midge fishing often involves fishing small, dark flies on light tippet, we needn't lock ourselves into a rigid mold when it comes to midge patterns.


Substrate disturbances from current turbulence or wading anglers make midge larvae more available in rivers during the winter. However, the tiny size of these insects and the speed of any moving current makes the relative difference between larvae and pupae miniscule, so one imitation for both should suffice.

There is a wide variety of proven midge pupa patterns, from the venerable Brassie to the WD-40. All are effective during most midge activity and are easily tied by anglers.

However, most tiers have trouble keeping the thorax and abdomen slim on small midge patterns. That's why I started tying the Minimus . This pattern is a simple, mini-sized variant of the several of the old stillwater chironomid patterns from the 1980's.

The Minimus is kept thin by only using a very fine silver wire rib, 8/0 thread body, and Ice-Dub thorax. The white CDC gills at the head and tail of the pattern are optional, and largely decorative (they don't help the fly float); however, they don't add much bulk to the fly.

This pattern is quick to tie and you only have to change the thread to change the body color. Olive-dun, brown, black, and tan are standard midge body colors, but some of my best success with this pattern has come with chartreuse and hot-pink bodies.


After browsing through hundreds of professional stomach sample reports, as well as doing my own sampling, it's clear that adult midges compose a tiny proportion of the average stream trout's diet. Adult midges, unlike mayflies and like caddis, remain on the water's surface for an extremely brief interval. A trailing "v" wake behind adult midges is a sign of their restless nature. Adult female midges lay their eggs by crawling down rocks or logs and laying eggs directly on the substrate. The same egg laying behavior in caddis and Baetis mayflies can result in heavy, selective feeding by trout. Yet, paradoxically, this behavior in midges seems relatively ignored by trout.

However, there are two times where imitating adults can be effective. The first is during cold or wet weather, which retards the ability of their tiny wings to dry. However, unless the fish are rising to midges, fishing a lone imitation is a slow, cold, and not very effective proposition.

Occasionally, however, you will see clusters of mating midges drifting or hovering on the surface of a stream in a whirring, buzzing mass. This is one of the rare occasions when adult midges can be particularly effective, since the large mass of insects is easier to imitate and more realistic than a single solitary midge floating down the water. Because clustered midges are both natural and big enough to move a fish more than a few inches, I prefer to imitate them rather than single adults.

The old reliable pattern for this cluster is the ppGriffiths Gnat. Rene Harrop and others improved on this fly by adding a tuft of white CDC as a wing, making the fly more visible and helping it float a bit better. When playing around with the CDC Griffith's Gnat, I decided to forgo the hackle and peacock altogether, and simply dub a small, loose body of dun and black CDC--and BOOM!, the Dustmop was born.

The combination of blended colors and light surface imprint gives an excellent impression of a whirring mass of adult midges. Since the pattern is all CDC, it floats well enough to suspend one or two dropper pupae and function as a strike indicator.

Like most cluster midges, this pattern is most effective in larger sizes, such as16-22. Sometimes the pattern can be torn up after a couple fish, and if you rib the fly with 7X tippet, it should hold up better.

Being Thorough

Thoroughness is key to proper midge fishing. Trout in cold water will not move to hit a tiny nymph, so you have to put it on their nose. This means that midges are not effective "searching" patterns, but can be productive if you locate a pod of whitefish or trout or are fishing a lie where fish can be fairly accurately located (major seam or a backeddy). Don't fish midges if you want to cast twice to a lie and move on. Strikes to midge imitations often occur on the fifth, sixth, or seventh apparently identical drift, because the fly was just an inch or two closer to that lethargic trout.

The most important thing with midge fishing is confidence. Don't worry about acquiring an encyclopedic collection of patterns in a variety of colors and sizes. You can rarely play match-the-hatch with midge patterns: they must be fished so thoroughly you can rarely give them a fair shot if you're changing flies every 10 minutes. Find one or two favorite patterns in a couple of sizes and stick with them.

New Patterns

Click the links below for photos and tying instructions.


Jeff Morgan has written many articles for Westfly, mostly on entomology and fly tying. He is the author of An Angler's Guide to the Oregon Cascades and Small Stream Fly Fishing.