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Reading the Stages of a Mayfly Hatch

You cast and cast and cast to the rising trout... and nothing happens.  It is as if the fish are eating everything in sight except your fly.  The problem might be that the fly you are using is not in sync with the stage of the hatch in process.

Every hatch happens in a series of stages.  Starting with nymphs as they head to the surface of the water from their subsurface homes.  These are are referred to as "emergers" or "pupa". This stage is often the easiest prey that a trout will ever get. The tell-tale signs of emerging nymphs are that the trout are ‘porpoising’ the bugs.  You see the dorsal fins and tails of the feeding trout, but you don't see the typical rings on teh water made by trout that are eating off the surface . Despite the fact there might be adults or duns on the water, the trout are focusing on emergers. There is a steady increase of emerger patterns appearing in fly catalogs as this stage is becoming a favorite of fly fishers. 

If you begin to see trout’s heads poking out of the water, there has been a subtle shift in the hatch as trout are feeding on insects in the surface film.  This is the proper time to try a dry or use a tandem rig with a short tippet and an emerger trailing the dry. As more and more strikes come on your dry fly, simply clip off the emerger.  Rotating your dry fly pattern seems to be effective as your strikes slow down. If you had been fishing a standard dry fly, try a parachute pattern, sparkle dun, or some other alternative.

Other considerations are your presentation, body positions, tippet and fly size. Your presentation needs to be delicate; the fly needs to float in the same direction, speed and manner of the naturals. Sometimes positioning yourself in the proper location is all you need to do. Upstream, downstream, across stream, these are calls that need to be made after consideration of currents, distance, and your own personal safety.

The tippet needs to be as delicate as possible small hatches in crystal clear water may demand at least a 6x, but may require all the way down to 8x. Fly selection needs to be as close to the natural as possible, then go smaller as the fish wariness increases.

The final strategy to be considered here is a counter intuitive method of throwing all the rules out the window and casting something totally unrelated to the hatch. This seems to work only in a long frenetic hatch or spinner fall when the fish are fat and seemingly intent of getting fatter. For some reason there are times when throwing them something unrelated attracts their attention. Likely choices must be something the fish see like a terrestrial pattern or an attractor pattern like a Royal Wulff or your favorite Humpy.