Winter Midges
by: Mike Lawson
One of the things I don't like about living in southeastern Idaho is the winter. I'm not much on winter sports like skiing, snowmobiling or ice-skating. In fact when people ask me my favorite winter sport I usually tell them "Monday Night Football".
There are some positives about the long, cold Idaho winters, however. It helps keep our area from growing too fast. There is usually a look of disillusionment when I tell a guy from California, who is looking for a good place to retire what our winters are like.
When I really think about it, however, I guess it really isn't too bad. Our hunting is about as good as it gets and, if you like to hunt waterfowl, you can do it through the first part of January. By mid February the worst of winter is gone and it starts getting warmer again. There are only about six weeks that are real bad. During that time I get dragged to the ski hill by my kids a few weekends and I spend quite a bit of time traveling to warmer parts of the country presenting my fly fishing programs. The coldest six weeks of winter goes by pretty fast.
Actually, fly fishing is my favorite winter sport. While most of us think of fly fishing as a summer activity, I probably spend more time fishing during the off-season than during the summer months. Fall is my favorite time to fish because the fishing is great and there usually aren't many other anglers on the water. Winter is also productive but the fishing isn't as attractive to me because it can really be crowded.
Winter opportunities are limited for fly fishing in southeastern Idaho during the winter months. The general season closes the end of November and after that time the only areas open for fly fishing are the Henry's Fork from the Vernon Bridge below Ashton downstream and the South Fork of the Snake below Heise. That really doesn't leave many opportunities in an area where fishing is so popular. On a warm winter weekend these areas are as crowded with other anglers as the Harriman State Park during Green Drake time.
All of our neighboring states offer more opportunities for winter fly fishing. In Montana few streams are closed during the winter months. I spend a lot of my time fishing the Beaverhead, Yellowstone, and Big Horn Rivers as well as the private spring creeks near Livingston. The Madison River has also been a favorite for many anglers from southeastern Idaho but it will be closed this season because of a dramatic decline in the trout population. Whirling disease is thought to be responsible.
Two of Utah's finest trout streams, the Green and Provo rivers, offer year round opportunities for exceptional fishing. There is no fishing season in Colorado and all streams are open year round. I've had some great fishing on the South Platte in January while visiting the Denver area. But in Idaho, it appears we'll have to be content with limited opportunities until our state fishery managers rise out of their 1950's mentality.
Since we don't have enough places, I'll try to concentrate on how instead of where to do some winter fly fishing. The few areas which are open to winter fishing don't need any more promotion.
Believe it or not, there are some excellent hatches of aquatic insects during the winter months. There are several mayflies that emerge late in the season but by December the only aquatic insects are midges. Midges are aquatic insects of the order Diptera, meaning "two wings" as the adults have only one pair of wings. Mosquitos, deerflies, gnats, and craneflies also belong to this group. While the word ÒmidgeÓ is synonymous with small, not all midges are tiny. I have seen some species almost an inch in length.
Midges have a complete life cycle that consists of an egg, larva, pupa and adult. Many anglers have a love-hate relationship with midges. They can produce some of the most exasperating and frustrating fly fishing experiences known to man but most anglers have an unknown kinship them because they make up more than 50% of the trout's diet in many trout streams. Without a good population of midges, the number and size of trout in these streams would decrease substantially. Midges accounted for more than 85% of stomach contents from trout I have sampled from the Henry's Fork in January.
Unlike most other groups of aquatic insects, midges commonly have two or more generations annually. In many instances, it only takes a few weeks between the time the eggs are deposited and the adults emerge. Most spring creeks and tailwaters have continuous midge hatches every day of the year. I have sat, freezing in sub-zero weather, watching trout feeding on midges amid the decoys, while hunting ducks in January on the Henry's Fork.
In the cold water environments of some tailwaters, midges make up the majority of the population of aquatic insects because they are the only group that can complete a full life cycle. The greatest populations occur in streams with mud or silt bottoms and substantial aquatic vegetation. The lower Henry's Fork and most sections of the South Fork provide exceptional habitat for these tiny insects.
Midge larva are worm-like in appearance. The colors range from blood red, olive, brown, black or grey. Sizes vary from 3mm to over 30mm in length. Most species are quite small, less than 10mm long. I have not found the larval stage as important as the pupae or adults because they usually stay buried in the muck or hidden in vegetation until they pupate. Stomach samplings have shown trout do feed on the larva but my experience fishing their imitations has been unproductive.
When the larva has matured it pupates. Some forms fasten themselves to bottom structure where they stay until they emerge. The pupae of the most common family which inhabit the Henry's Fork and South Fork (Chironomidae), are free swimming. The pupa is shorter and more rotund than the skinny larva. The abdomen is well-segmented with a robust thorax composed of turned down wing pads, gills and legs. Because these pupae are free swimming they can be fished successfully at any time.
In the hours prior to emergence, the pupae become restless and begin a series of rises toward the surface before settling back down again. This motion is repeated several times until they make the final ascent to emerge. Multitudes of wiggling, rising pupae send the trout into feeding motion. When the pupae reach the surface film, they remain suspended, hanging down with the thorax against the meniscus, until the adult breaks the pupal sheath and pushes through the surface tension.
The time the pupae drifts, hanging against the surface film, can vary from a few minutes to more than an hour. It is during this period that the pupae are most vulnerable to the trout. Trout sip them lazily, forming the tiniest dimple in the soft currents.
When emergence takes place the adult pulls out of the front of the suspended pupae thorax first. The top of the thorax of the emerging adult pushes through the surface film. It then uses its legs to push against the surface to pull the rest of the body out of the pupal sheath. During this period the emergent midge looks almost twice its normal length with the empty pupal skin hanging suspended to the adult's body. After emergence the adult rests on the surface only long enough to flex the wing muscles. The adults hover on surface, the wings gyrating like tiny propellers, when the weather is cold.
Many adults do not complete the emergence process, leaving them entrapped partly in and partly out of the pupal sheath. Cripples are deadly imitations of these doomed midges. Cripples can be tied on standard sized hooks, leaving some fibers of maribou or Z-lon yarn to represent the trailing husk or they can be tied on a longer shank hook with the shank tied two tone, the bottom third the color of the pupal husk and the upper two thirds to represent the trapped adult. The second method offers the advantage of using a larger hook when very small midges are emerging.
Many anglers shy away from fishing pupae, emergers or cripples because they are impossible to see. Not only is a drag-free drift essential to catch selective fish, but the position of the fly in the surface film is critical. The pupa is most effective when drifting just under the surface film. Cripples and emergers should be drifted half in and half out of the meniscus.
One trick is to get as close to the rising fish as possible. You still probably wont be able to see the fly but at least you'll have a better idea of where your fly is so you can strike when you see a rise in the general vicinity of where you think it is. You should also grease the tippet as well as the portion of the emerger or cripple that is supposed to be out of the water. You can't grease the pupa, just the tippet right up to a half inch from the fly. Don't worry about the tippet floating. Not only must your fly drift naturally, but your tippet too! It is surprising how well you can see the crease in the surface from the tippet if you can get the right angle. Watch the tippet to determine if you are getting a natural drift and if it moves when a trout takes the fly.
Some anglers like to use an indicator with flies that are too small to see. I don't like to use one because I believe some trout spook from an unnatural color, like fluorescent orange, suddenly appearing in their window of vision. Even a small indicator can also cause drag on the fly. I have found using a second fly is the best trick to use when fishing midge pupae and cripples. The top fly should be a highly visible dry midge pattern like a Royal Wulff, Parachute Adams or Griffith's Gnat. The pupa or cripple should be tied as a dropper not more than ten or twelve inches from the upper fly. You can either tie the dropper to the eye or bend of the upper fly or run the tippet through the eye of the upper fly and tie the tippet for the bottom fly. The tippet will slide through the eye of the dry fly but it will stop at the blood or surgeon's knot used to tie in the second fly. I prefer the second method. The trout will not spook from the dry fly used as an indicator and may take the dry fly as well as the dropper.
Anglers frequently make the mistake of trying to use adult imitations because they can see them buzzing all over the water. Patterns which represent pupae, emergers and cripples are usually much more productive than adult imitations. There are occasions when adult patterns are effective, however. Midges have a tendency to clump together whenever adults are concentrated together. Wind can concentrate large numbers of adults into specific drift lanes. The females are often larger and colored differently than the males. Several males will try to climb on a single female an attempt to mate. Trout target these "clumps" of midges as they drift on the surface.
My favorite pattern to imitate clumps of midges is the Griffith Gnat, created by George Griffith. It is interesting that this excellent pattern did not receive the credence it deserved for many years. I first read about it in Schwiebert's Nymphs, but didn't actually know what it looked like until George Anderson gave me a few when we fished Nelson's Spring Creek together on a overcast February afternoon. Schwiebert used it to imitate the emerging pupae. I like it better when the adults are clumped together. Nothing looks more like a clump of mating midges than a Griffith's Gnat.
You'll find trout rising in the quiet backwaters and glides of the Henry's Fork and South Fork all winter long. The first time I tried fly fishing in the winter was when I was in high school in Sugar City. One particularly nice January day I had a bad case of cabin fever. Randy Roberts and I stopped in to the merc to talk with Emery Thomas, the owner who seemed to always know everything we needed to know about hunting or fishing. We usually headed straight for the merc after school to swap stories. I'm sure there were more fish caught and more game killed in the back of his store than any place in the west.
Emery suggested we try some fly fishing up on the North Fork near Ashton. He rigged us up with an assortment of "snowflies" to represent the tiny winter midges and drew us a little map of where to go. The flies were pretty small but he assured us they had to be or the fish wouldn't hit them. When we arrived at the river there were fish rising everywhere just as Emery had promised. We couldn't keep the flies floating and couldn't see them. Finally we gave up on trying to fish them dry and found that if we cast just above the rising fish and let the fly drift down and then lifted the rod tip and twitched the fly at the right time, the trout would hit the fly wet. We both caught a nice mess of fish and couldn't wait to get back and tell Emery.
I still use the wet fly technique today. For some reason the trout will smack the fly wet if you drift it past his holding position. I like to position myself slightly above and across from a pod of rising fish. If you're fishing wet, try using two or three flies at once, tied about a foot apart down the tippet. When the flies drift into the feeding lane lift the rod tip enough to tighten the line and allow the flies to swim past the trout. You'll feel a slight tug on the line when the fish hits and you can softly set the hook.
You can also catch plenty of trout on nymphs and streamers during the winter months. I've caught some of my biggest trout fishing streamers on the South Fork or Henry's Fork when the weather was so cold it iced up the guides on my rod. You can also get lots of fish using a couple of nymphs with an indicator and drifting the flies through the riffles. I don't find these methods as enjoyable, however, as casting midges to rising trout. It can get pretty miserable stripping your line through cold fingers while fishing streamers on a cold winter day. It's also hard to bring myself to try to dredge up a hidden trout on a nymph when I can see them rising on the surface. It's just too bad we don't have more places to do it.