Midges, midges, and more midges. Midges are one of the four main aquatic insects in our western freshwater water systems (stoneflies, caddis, and mayflies make up the other three). They are the most diverse of these four species meaning they have the most sub-species. There are over 1,000 different midge species making their identification challenging on the river. But don’t let that stop you, fly fishing with midges can be very straight forward if you have a basic understanding of their lifecycle. As well as a few of the basic techniques to fish them effectively.
So break out the thin tippets and start fly fishing with midges today, your catch rates will improve, especially in the colder months. And if you are thinking you don’t want to fish with the indicator, midges can be effectively fished on the surface or as emergers just below the surface. Check out the full blog below to familiarize yourself with the midge life cycle, techniques for midge fly fishing, and where and when to fly fish with midges here in Colorado.
Why Fish Midges?
Midges are present in almost all freshwater bodies of water from freestone and tailwater rivers to stillwater lakes. In some systems, they can make up more than 50% of a trout’s diet. This is most likely due to the fact that midges are readily available, they hatch year-round, 365 days a year. A midge can complete a life-cycle in less than four weeks. Other aquatic insects like different stoneflies need months or even 1-2 years to complete a lifecycle, couple that with specific water temperatures and oxygen levels some stoneflies won’t even hatch.
Midges on the other hand are very abundant as they have a wider range of hatching water temperatures and oxygen levels. If you aren’t fishing midges you are missing out, they can turn a slow day on the river into a very productive one.
The Midge Lifecycle:
The midge lifecycle is quite simple, it has four life stages: egg, larvae, pupae, and adult. It is important to understand the three stages of larvae, pupae, and adult stages as it pertains to anglers. Once the midge egg is laid it will become dormant anywhere from a few days to a few months based on external conditions.
After the egg has hatched the midge becomes a larva. This larva looks like a tiny worm. The larva is found in the substrate of the river or lake, it can be mixed in the river bottom, drifting through the river, or clinging onto river debris (sticks and rocks). The larvae are very small, they can be comparable to a size 18-24 fly. Midge larvae can be found in a variety of colors, most often black, red, or olive. Midge larvae are most active during the night, so if you do find yourself nymphing at night, larvae imitations can be effective.
Recommend Larvae Fly Patterns:
Neon Nightmare Midge #18-22, Mercury Midges #18-22, Blood Worms #18-22, Blood Midges #18-22, Rojo Midges #18-22, Barr’s Pure Midge Larvae #18-22, Demon Midge #18-22, Miracle Nymph #18-22, and Mighty Midge #18-22.
Once the midge larvae have reached maturity they begin to hatch and become pupae. The pupae are much shorter and stockier than the larvae as the wings, legs, and gills have begun to form. The pupae are not clinging to the bottom of the river substrate. Instead, they are typically found just above the bottom wiggling around trying to break free of their larvae sheath. Once the sheath is shed they begin their journey to the surface of the water. As this happens, a small air bubble is formed on the head of the midge. This can be imitated with flies by adding a flashy bead-head, flashback, or tuft to the fly.
The pupa stage of a midge is typically short it can last a few hours or a few days but it is typically when the bug is most vulnerable to a trout. Making this stage the most effective for anglers to have success. When these pupae begin to hatch and make their journey to the surface it can really turn on the fish activity.
Recommend Pupae Fly Patterns:
Rainbow Warrior #18-22, Black Beauty #18-22, Juju Bee Midge #18-22, ICU Midge #18-22, Zebra Midge #18-22, Top Secret Midge #18-22, Biot Midge Emerger #18-22, Disco Midge #18-22 and the WD-40/WD-50 #18-22.
The midge becomes an adult as it breaks the surface of the water and begins to wriggle out of their pupal sheaths. The wings become visible, as the midge begins to shuck the pupal sheath. It will then sit on the surface of the water briefly as the wings begin to dry. The midges display a small tented wing that looks very similar to a mosquito or gnat. Anglers can use small dry flies that imitate a single midge or a dry fly like the Griffiths Gnat or Renegade that imitate a cluster of midges. The adult midge can live anywhere from a couple of days to a couple of weeks.
While adult midges can often be considered mosquitos, they are in fact not. Midges do not bite and don’t have scales on their wings. So don’t assume the midge hatch on the river will turn into biting mosquitoes!
Recommend Larvae Fly Patterns:
Smokejumper #18-22, Renegade #18-22, Roys Midge #18-22, Sprout Midge #18-22, Eric’s Midge #18-22, Snowshoe Dun #18-22, Matt’s Midge #18-22.
The life cycle of the midge filmed underwater. Video from “Bugs of the Underworld”.
Techniques for Fishing Midges:
Due to the fact that there are thousands of different midge species, don’t get caught up trying to identify a specific midge species to properly match the hatch, instead focus on identifying the specific part of the life cycle the midges are currently in. Once you have identified the specific part of the lifecycle the midges are in asses the size and color of the midge and do you best to imitate this.
More often than not start out with a nymping setup with two flies one imitating the midge larva and the other a midge pupa. Separate the flies about 14-18 inches apart. Put on the midge larva as the bottom fly and the pupa as the lead or attractor fly. As the pupa is typically higher in the water column. Begin to fish this setup, set the depth for about 1 ½ the depth of the water you are fishing as you want your flies to ultimately dredge the bottom as this is where the larvae would be.
As you begin to fish, monitor what flies you catch your fish on, and change your rig accordingly. If you are not getting any action on the pupa fly switch to two larvae imitations. And if the fish begin to key in on the pupa, switch both flies to a pupae imitations. Slightly adjust your indicator higher as the pupae will be concentrated higher in the water column. This most likely means that the midge hatch has started and activity should really begin to heat up. It also might mean that the trout might transition from opportunistic feeders to selective feeders. Be sure to try to match the hatch and set your depth correctly. As a selective trout is a pickier trout.
Adult Midge Fishing Techniques:
As the pupae become adults, the trout transition to eating these adult midges. Look around for slack water or back eddies where you can check for risers or natural bugs. If you want a challenge, snip off the nymphing rig and toss on a midge adult fly imitation. The midge adult fly can be challenging to cast and see, so having a higher visibility fly like a sprout midge can improve your chances of seeing the midge. You can also tie on two dry flies with a larger (size 16 or 18) fly on the front and the smaller midge adult or emerger behind it.
Improve your chances by finding active feeding fish and target these fish. It can be a waste of fishing time to blindly cast the midge adults. As there will be typically a lot of competition from the natural bugs.
Gear for Midge Fly Fishing:
Next time you stop by your local fly shop be sure to load up on midge larvae patterns in different colors and sizes, midge pupae patterns in different colors and sizes, and a few midge adult patterns in different colors and sizes. Find a pattern that works for you, generally, the zebra midge or rainbow warrior is a great place to start and buy or tie this pattern in a variety of colors and sizes. The Umpqua Midge Fly Box is an great box to organize your midge flies.
As for other tackle, a 9 foot 5 or 6 weight rod is the go to rod size for fishing midges. Due to the subtle takes on light tippet a softer tipped rod can be more effective. Something like the Scott Flex is a great rod for midge fishing. A 9 foot 5x or 6x monofilament leader with 5x or 6x fluorocarbon or monofilament tippet will be effective. The fluorocarbon tippet will likely result in more hookups when going subsurface, as the tippet material sinks fast and is more subtle in the current. The monofilament tippet is effective when imitating midge adults on the surface.
A tippet ring nymphing setup can be an effective way to set up your rig. Split shot is also a necessity when nymphing to get your flies down in the water column fast. Carry an assortment of sized split shot to fish different depths and current speeds effectively. An airlock indicator is essential for nymphing, the indicator can easily be adjusted to the correct depth. As for reels, since a lot of midge fishing takes place in the cold a fully sealed drag is a must, the Ross Evolution or Animas is a great option.
Midges in Stillwater:
This article wouldn’t be complete if we didn’t mention anything about stillwater fishing and midges. The largest and most identifiable midge species is the chironomid. Chironomids are lake dwelling midges, they are often larger than most midge species that hatch out of the river. When targeting stillwater fisheries here in Colorado a chironomid imitation will often be an effective way to catch a trout.
When Should You Fly Fish Midges:
Midges hatch year round 365 days a year in all the different river systems here in Colorado. They are most common and prolific in the colder months from November to April. Midges can also be fished in the late summer when the water temperatures are warm. Usually, when there is not a lot of other bug activity, midges will be the first to begin hatching. Try starting out the day by fishing a midge larvae and as water temps begin to warm and bug activity begins to stir a pupae pattern should work. And if you are lucky the midge adults may hatch and a dry fly is a must. The lower light days provide more opportunity for surface activity.
Where Should you Fly Fish Midges:
By now it is clear that midges are present in almost all bodies of water with trout. On our local rivers (Eagle River, Gore Creek, Colorado River, Roaring Fork River, Blue River, and Yampa River), midges are the go-to bug of choice in the “off-season” (November-March). Midges do seem to be more effective in the specific tailwaters here in Colorado like on the Frying Pan and Blue River. But, our guides will almost always have a midge on when guiding the Eagle River in the “off-season”.
Next time you don’t see any bugs hatching on the river or are stumped with what the trout are eating tie on a midge and I’m sure you can find a willing trout. They might be small but they sure are deadly!
Patrick Perry, Content Contributor, and Former Guide @patperry