Curiosity has led me to purchase a couple of books on odonates (damsel and dragonflies). This is from Dragonflies and Damselflies of the West (Dennis Paulson, 2009): "After leaving the water as a teneral, an odonate slowly continues to harden and color up. The color is often different from the color at maturity, and it changes over a course of days or weeks or even months as the individual becomes sexually mature and returns to the water, completing the cycle. ... After (this) immature phase, most temperate-zone odonates live a surprisingly short time. Small damselflies live no more than a few weeks, larger dragonflies month or two".
Last weekend must have been one of the first real good damsel hatches. Caught well over 20 fish with a type III, Uniform sink line and a fair imitaiton of a damsel hatch. Today, same water erupted again but about an hour or so earlier. Five or six fish and only one on the same damsel pattern that worked like a charm only a week earlier. Ralph cutter was right, except at the early stages of the hatch.
Cutter stated that damsel undulations were impossible to duplicate in fly patterns. He also stated that damsel nymphs rested/settled during their journey to the surface. This rest/settle interval was our one chance to catch the picky trout.
I believe the first few days of the damsel hatch you could probably cast a reasonable duplication with success. The fly I was using was quite a bit larger, heavier with a tungsten bead, and only a fair duplication of the actual color. Also, a type III, Uniform sink line did not duplicate the natural rise of the nymph. Nevertheless, a fish on almost every cast.
Same water same stuff, one week later = only one fish on the same system, ala Ralph Cutter.
I agree about the imitation of damsel swimming motion being impossible to recreate. I tie my own damsel pattern that features a fairly short body, burnt-mono-eyes, and a bit longer than body tail that is marabou. The point of this fly was to be able to fish it really slowly with micro-twitches of the rod tip to get that marabou tail to wiggle and sway, like the wiggling motion that a damsel exhibits. It's not exact, but playing with the fly where I can see it, micro-twitching it, it's closer than any fly I've bought or found a pattern for.
I tie this in shades of tan, olive and browns. It's articulated, slender in profile and sports marabou for added movement.
It's not a complex tie. mono eyes, marabou, dubbing and razor foam are the components.
I will post a tute as time allows me.