For a few short weeks every summer a very special event takes place under the cover of darkness: the Hexagenia hatch. Hexagenia limbata is one of the most prevalent mayflies found across North America. This genus can be found from coast to coast and from Canada to Florida. These hearty mayflies make up a large important part of the food chain in clear water lakes and slow moving streams. For fly anglers, the hex hatch is one of the best opportunities to fool large trout into biting. Maybe it's the size of the insects hatching or the sheer numbers that they hatch with, but hex flies absolutely drive fish wild. Trout will gorge on these insects, feeding repeatedly out in the open.
As amazing as fishing the hex hatch can be it is not without its difficulties for anglers. First and foremost, getting the timing around when these bugs decide to come off the water is not easy. In Wisconsin, you can be pretty sure that any time around July 4th, or when the weather has been predominantly in the 90s, you will see start seeing hex flies. Don't look for these flies in the day time though, as hex flies won't hatch until the sun goes down. Pick a slow run on your favorite river and stake out the banks until about 30 minutes after the sun goes down. If you don't see any flies by then you can be pretty sure they are not going to be hatching that night. If you do happen to be on the river when the flies hatch, be patient with feeding fish. A lot of inexperienced anglers will run up and down the banks chasing slurping fish and end up with nothing. If you hear a fish feeding, just position yourself and wait. Most fish will not move very far while feeding and will rise in almost a predictable rhythm. Don't waste time with long drifts with your flies. If the fly has drifted 2 feet past where you saw the fish feed, pick it up and rerun the drift. In some cases fish will feed one to two dozen times so if you miss them once or twice you might be another shot.
Seeing as you will be basically be standing in a swamp at night while waiting for these mayflies to hatch, two simple items will make your trip a success: insect repellent and a headlamp. I will be honest the mosquitos during the hex hatch can be quite intolerable but a strong bug repellent can make your time a lot more pleasant. An easy to operate headlamp is also a necessity. Whether it is on your walk out or while you are fighting a big fish you are going to need light at some point. Having a headlamp that is easy to turn on and off is what you are looking for in these conditions.
Flies for the hex hatch don't need to be anything special. Since it is dark out when the bugs actually come off the water fish will not get a very good look at your patterns. Be more careful about matching size then the color of flies. Synthetic materials flat out just work better than naturals for this type of fishing. Closed cell foam makes super buoyant bodies that can take a beating from fish or snags while still floating high and dry. EP fibers tied in as wings are another good addition to hex patterns as they provide the look of bulk without adding additional weight on flies.
The hex hatch can be some of the best trout fishing of the year for fly anglers as long as you are prepared for what the adventure is going to look like. Be equipped for fishing in the dark, mosquitos, wet conditions and some of the most voracious feeding trout you will ever come across.