Fly Fishing Montana Drake Hatches

During summertime in Montana the bug life awakens after a long winter submerged in the cold waters of Montana rivers. As the weather warms up, so does the fishing. The Green and Brown Drake hatches are a momentous emergence of insect life. Fish key in on these hatches and attempt to eat as much as they can during these short summer hatches. Thye are a prolific food source for trout in the rivers near Bozeman and offer exceptional dry fly fishing for anglers in the early summer. They thrive in river habitats and emerge from the sand and silt bottoms, where they burrow as nymphs, to shed their outer layer and complete their final stages of metamorphosis. Fish feed on these aquatic insects throughout the many stages of their life cycle.

Nymph Stage

Once these mayflies hatch from eggs they start the journey to becoming fish food. The nymph stage takes up the majority of their life, therefore offering food sources in both nymph and adult stages. While in nymph form they may molt up to 50 times as they outgrow their exoskeleton. They are exceptional swimmers and spend most of their time burrowed in the silt of the riverbed, but eventually, emerge after 1-2 years in their nymph stage. They swim to the surface in calmer water, split their exoskeleton, and emerge as a dun. This is an easily recognized event because of their large size and the triangular sail shape they make with their wings as they ride on top of the water. Within a few minutes, they are able to fly and begin the mating process.

Mating

The dun and spinner stage drakes do not have any mouthparts are unable to eat, therefore making their adult stage a short-lived experience, essentially restricting their actions to mating. Once they emerge as duns they have one more step to becoming sexually mature. From duns they molt and become spinners, which are slightly smaller and have transparent wings. They will start mating as evening falls, they form large clouds where they mate, then the females drop to the water to release their eggs. They will then remain on the water's surface, these are known as spent drakes, having now fulfilled their life purpose of laying eggs.

Green VS. Brown

Green and brown drakes have the same life cycle and often times occupy the same rivers. In the Southwest Montana area, there are both Green and Brown Drake hatches. The Yellowstone River and Gallatin River have exceptional green Drake hatches, but timing is key when fishing these hatches. They typically hatch during high water on these rivers so clearer water conditions and lower flows are needed to effectively fish these large mayflies. The Lower Madison hosts a large Brown Drake hatch and is easier to fish because of the Lower Madison’s dam-controlled flows that are not as easily altered by runoff.

How to Fish the Hatch

When fishing these hatches an angler will need to correctly match the stages of life the surrounding mayflies are in, as the trout key in on different variants of the drakes. If there are plenty of duns on the water but there are no fish feeding on the surface the best method will be to fish the drake nymphs emerging from the river bottom. This can be accomplished by dropping a drake emerger off of a drake dun.

Some effective patterns for the dun form are the Neally Green Drake and the Hairwing Brown Drake. Large soft hackle flies will be suitable for mimicking the emerging bugs still trapped under the surface of the water. The dun patterns will look different from the spinner stage, the wings will not be translucent like the spinners and they will be sitting on the top of the water with sail-shaped wings. Once they mate they will fall back on the water in their spent spinner form. These patterns of fly will have clear wings that lay flat on the water. Good patterns to imitate this stage are Brown Drake Clear Wing Spinners and the Missing Link Green Drake.

Top Fly Patterns For Fly Fishing a Drake Hatch

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