The Holy Hex (Hexagenia Limbata) Hatch
by: Bob Shannon
As the warmer days of summer approach in the month of July, still-water fly fishermen are in anxious anticipation of one of the premier hatches of the season. May fly fishermen refer to this as the holy hex hatch, whose sheer size leaves anglers in awe of its enormity. The hex May fly is the largest insect the northeast region has to offer. It’s giant size will bring large fish to the surface to feed even during the warmest days of summer. To give the first time still-water fishermen a chance to succeed during this still-water hatch you first must break down the cycle into a few easy steps. These steps are key to catching some of the massive fish found in northeastern lakes. The Hexagenia May fly is a burrowing aquatic insect that requires soft, sandy lake bottoms in order to thrive.
A little pre-hatch research of lake topography to put you in water depths of 25ft or less will be a HUGE first step in locating the prime areas of the lake to find these hatches and feeding fish. Most river fly anglers find the transition from river to lake and pond fishing to be a trying task due to the lack of readable water that you find in your river fishing scenarios. This May fly is unique to its late evening hatch. These bugs will break the surface of the lake just a few minutes shy of darkness. Most new hex anglers feel the need to leave the lake just before the hatch really begins, thus missing the prime time of hatch.
Here are some of the steps you may want to use for landing the big ones. I begin targeting fish with hex nymphs around 7pm, and try to fish them close to the bottom of the water column. I cast with a 10ft express sink tip leader with four to six feet of 4x fluorocarbon tippet to retrieve my hex nymph. This targets fish that are preparing for the upcoming evening hatch. This can seem like a tedious approach at first when targeting lake fish, but is very effective before dusk.
As the bugs begin their ascent from the lake bottom I switch flies to a large soft hackle hex emerger. I fish this fly with a long 4x or 5x 9’ fluorocarbon leader and use Henry’s sinket wet fly paste on the fly. This paste assures that the fly will sink to 4ft below the water surface. Fishing this fly with a slow one to two inch at a time retrieve at that depth will produce fish as they move towards the surface to feed on these large bugs as dark approaches.
As dusk sets in, the giant yellow colored May flies flutter on the surface of the water and the sound of slurping fish and rings of surface feeding fish blanket the lake. I continue the fishing with the same leader that was used with the previous fly; however I change to a Hex dry fly imitation. This fly will need to be prepped with a good dry fly floatant. Loon’s Aquel, or Loons dry fly spritz spray is key for keeping the fly on top. The use of the fluorocarbon leader will sink the leader just below the surface making the leader less visible to the fish. This will give the dry fly a more realistic look in the flat water. As you fish this hatch it’s easy to get caught up in the excitement of seeing great numbers of rising fish. A common mistake made by even a veteran dry fly fisherman is to chase the rising fish. This will lead to a long night with few if any fish boated. Different from river dry fly fishing where fish can hold in a current and wait for the food to travel to them, still water fish will need to cruise just below the surface in search of their prey. Chasing these rising fish is a difficult task and a guessing game as to the direction they are traveling. I find a much more effective method is to cast and work the fly over as great a distance as your patience will allow. The fish will find your fly if you give it time and work the fly with a slow retrieve for a more realistic look. I have had many frustrated anglers come into the shop with stories of how few if any fish they have landed during a prolific hex hatch with rising fish everywhere and nothing to show for it. My target species of fish to catch during this hatch would be rainbow trout, however depending on the lakes that you intend to fish during the hex hatch you will find a wide variety of rising fish. Some of my biggest bass, yellow perch and blue gill of the season will be caught at this time of the year.
Remember a fly on the water ALWAYS catches more fish than one that’s in the air while you’re casting.