| Scientific Name: | Various - 175 Genera and 1000 Species |
| Class: | Insecta |
| Order: | Diptera |
| Family: | Chironomidae |
| Common Names: | Midge, Gnat, Cranefly, Snow fly, Blood Worm, Deer Fly, Black Fly, and Mosquito |
Midges make up a huge portion of the trout diet in our cooler northeast waters. Bigger morsels exist because of both size and at times availability to the fish. But these large mouthfuls such as the mayfly, Caddisfly, stonefly, dragon and damselfly activities come and go. However the lowly midge is around in large numbers year round and fish will always from time to time return to their ever present offerings. If you fish waters where nymphs are not producing, you may want to tie on a few midge patterns to change your luck. Midges belong to the order Diptera: di meaning "two" and ptera meaning "wings." These are also referred to as real flies. More precisely they belong to the midge family, Chironomidae. These are small two-winged flies in the adult stage. They are closely related to Mosquitoes and Chaoborus (Phantom Midge or Glassworm).
These mosquito-like insects range in size from about one-half inch (12mm) down to the famous no-see-um size of less than one-eight inch (3mm). The most common body colors are black, dark charcoal, grey and various shades of reddish brown to greenish brown.
Compared to the Mayflies, Caddisflies and Stoneflies, fly fishers know very little about the large group of insects, called Midges. These species represent such an enormous diversity of color, size, behavior and locale that fly fishers, as a rule, have not attempted to deal with this genera, much less the species.
Midges undergo a complete metamorphosis, the first being the larvae which emerge from the deposited eggs. Often these larvae will be dislodged from the substrate, wiggling frantically in the current, making themselves an easy meal for feeding fish. After the larval stage is complete, midges then enter the pupal stage, where tiny air bubbles are created within the body of the insect and this process helps the insect to slowly rise to the surface. This attempted emergence will take several tries to reach the surface, as the pupa can bob in the current trying to rid itself of its nymphal shuck just underneath the waters surface where the insect waits to emerge as an adult. The final stage of the midge life cycle is the adult stage, where six legs will develop along with two wings. Once the insect has left the water, its main goal is to mate and return to the water where the female will deposit her eggs. Adults swarm and mate in flight. Most lay eggs singularly or in strings while skimming over the water surface. Some species lay eggs directly on vegetation or bottom substrates. The eggs hatch into Larva and form mud tubes from the bottom material and mucous. A few species have free-swimming larva such as the Bloodworm and Glassworm. The Larva then grows and develops into the Pupa stage. When fully grown, the Pupa wiggles their way to the water's surface. It often will take several minutes for the Pupa to get through the "surface tension" of the water before it can hatch.
The process of breaking open the Pupal Shuck, the adult crawling out, drying its wings, and flying away is usually accomplished in less than a minute. Once hatched these adults may live for only a few hours or up to a few months depending on the insect's species. Some species prefer the bottoms of lakes and ponds, while others inhabit the riffled areas of rivers and streams. Some will crawl among the aquatic vegetation; others swim freely in the open water. Some have gills and others have breathing tubes. Some are almost microscopic in size, while others will be some ¾ of an inch in size.
The various larvae of Diptera are mostly legless, slender, and wormlike. They are very often brightly colored red, light green, purple, cream, tan or black.
Now, after reading about all the different species, sizes, shapes and colors, the next question concerning anyone not familiar with midging is what the heck do I use for a fly? Fear not, with over 175 genera and over 1000 species this chironomidae family is large but not difficult to imitate. All these various differences aside, hatching midges, suspended at or in the surface film, do not present a great challenge to the fly angler.
Most midge pupae and the adults are very similar in shape, so now the need is to match the size and color. Your still water midges tend to be much larger (#10 to #18) while their flowing water cousins are much smaller in size (#18 to #26).
Appearance
The Larva has segmented bodies, is worm-like and looks much like a long skinny grub or maggot. This appearance gradually changes as they develop into Pupa. The Pupa develops an eye-spot and wing casing and most notably have feathery white gills near the head. The head and wing casing are usually one quarter to one third of the body length and the abdomen has 7 or 8 segments. The adult insect looks much like a Mosquito with feathery antenna. The good news for as anglers is that these midges regardless of species have very similar characteristics such as shape, texture and overall appearance.
Size
Pupa, are up to 20mm long (3/4") but average 8 to 15mm (1/4" to 1/2"). The still water species (lakes and ponds) are hook sizes #10 to #18 and the flowing species (rivers, brooks & streams) are sized #18 to #26.
Color
The Pupa tends to be black, brown, reddish-brown or green but can come in a variety of other colors. There is a type of free-swimming Chironomid Larva that stores oxygen in its blood and therefore red in color (Bloodworm). There is also a free-swimming Larva of the Chaoborus family that is virtually transparent and thus called a Glassworm.
Movement
Free-swimming larva like the Bloodworm and the Glassworm, do just that. They crawl, float or swim around the water column but generally tend to hide under rocks or decaying debris and remain fairly immobile. Most Larva build and stay inside a mud tube on the bottom and don't move around. When the Larva develop into the Pupal stage, they leave their mud tubes or other hiding places, fill air sacks within their skin for buoyancy, and slowly wiggle their way to the surface to hatch.
Habitat
As long as they can find a food supply, Chironomid Larva will live in almost any type of water. Clear or polluted with bottoms that are muddy, rocky, weedy or sandy doesn't seem to matter. However, their food source is generally most abundant on or near shoals and this is where their numbers peak. The preferred food source seems to be the Blue-Green Algae. The Pupal and Adult stages of these insects do not feed. These tough insects will even be very active in the dead of winter when most other insects are still crawling around the bottom. In fact, as long as ice isn't covering the water's surface, these species will continue to hatch year round.
Importance to Fly Fishing
After freshwater shrimp, Chironomids are the next most important food source for trout. Throughout the fly fishing season, daytime feeding samples show that 27% of the trout's daytime feeding consists of these insects. This percentage drops to about 14% for those fish feeding during the low-light conditions of evening. Also, during the winter months, when almost all other insect species hatching activities are closed for the season, the Midges continue to hatch, even on the coldest of snowy January days.
Hatches
Seasonal peaks occur from the third week in May to the second week of June and then steadily decline into the fall months. However, very large hatches of individual species can occur at most anytime of the year. As long as the surface of the water is clear of ice, these little tough insects will hatch. Chironomid larva on the bottom will sometimes exceed 50,000 individuals per square meter and thus form major hatches.
Always use an imitation that is slightly larger than the observed species. Most hatching activity occurs between the hors of 10 a.m. and 3 p.m.
A typical Maine angler has a terrible prejudice against fishing midges, which emanates from a sense of insecurity born from the inability to see the fly on the water. Why some anglers can confidently fish nymphs up-and-across but abhor the thought of fishing midges with similar techniques boggles the mind. So let's make the difficult simple to understand. The trick, then, isn't to be able to see your fly at all, any more than it is to be able to see a nymph as it dead drifts downstream toward you under water. Instead, the technique is to know precisely where the fly is at all times, so that when a fish rises for it, you can set the hook. This problem is corrected by the use of a bobber, oh sorry, a "Strike Indicator."
To present your imitation to a rising fish requires that you be positioned to get an absolutely drag-free drift. Although your midge pattern may be no more than a wisp of dubbed fur on a #26 hook, if it drags the fish usually will reject it and additionally be spooked and go down for the count. Your task is facilitated by planting yourself across and somewhat down-stream of your target fish, then three-quartering the fly up-stream casting either a right or left curve into your line and leader, depending on whether the stream flows from right to left or left to right.
Now, for the rigging, long fine leader tippets are generally essential to successful midge fishing, because
1. typical Diptera water is slower, flat and clearer,
2. heavier tippet material just won't thread themselves through those little hook eyes, and
3. the fine tippet material enhances the impression of a free-floating insect
I use eight (8) feet of 6X to 7X fluorocarbon tippet material, which ironically, makes presenting the midge a more manageable challenge than trying to do so with the more conventional tippet lengths of three or four feet.
Fishing Larvae
The first deals with fishing the larval stage of the midge. Because these larvae will be knocked off the sub-surface, they will be included in the biological drift. One tactic is to tie a larval pattern onto your tippet, then attach a eighteen inch (18") section of material onto the imitations hook bend to this tag end of your tippet attach a weight of some kind to bounce along the bottom, keeping the imitation in the current within the feeding lanes. This technique will keep the fly at the same depth as the feeding fish.
Fishing Pupae
This is the second technique: These very small imitations can be somewhat difficult to fish, so here's a tip! Even fished on the surface, a pupal imitation that represents a helpless insect struggling in the film to free itself from its shuck prior to flight, has proven considerably more effective than a dry midge that floats high on the water. At the end of your tippet tie on a size # 16 or #18 Griffith's Gnat. Now attach a twenty inch (20") section of material to the Griffith's Gnat's hook bend and tie on a Bead-head midge nymph or pupae. Depending how rough and deep the water is, may also call for a "strike indicator."
Now that your all rigged up, cast up and across to the head of the riffle and allow the imitations to drift drag-free until below you, then rise the rod tip and as the line straightens out will cause the imitations to suddenly rise towards the surface just like the emerging midges. If you plan well, this rise will occur just within the two-foot strike zone of a feeding fish.