Tiny Baetis mayflies are perhaps the most commonly encountered and imitated by anglers on all American trout streams due to their great abundance, widespread distribution, and trout-friendly emergence habits.
Ephemera guttulata's size, numbers, and hatching characteristics have made it a favorite of fly fishermen since the sport first came to North American waters.
It is on par with the Midwest's Hexagenia limbata hatch for its ability to lure huge piscivorous brown trout to eat insects at the surface once a year. The special charm of the Green Drake hatch is that it often takes place during pleasant spring afternoons. It can be challenging because the large flies are easy for trout to inspect in the daylight and they feed very selectively, especially late in the hatch. The huge difference in appearance between green drake duns and the spinners, white-bodied "coffin flies," makes them a peculiarity among major hatches.
The Green Drakes are on the decline due to environmental degradation.
Entoman on May 23, 2014May 23rd, 2014, 8:50 pm EDT
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"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman