But, here are R.M.’s thoughts, which I think are more accurate than my POV:
I don’t think curiosity plays a role. I think they have 2 options: It is food, or it isn’t food. [Pressured fish] start to see some flies often enough to KNOW that they are not food. Trout are not quite as discerning as people say, so they eat a lot of things thinking they aren’t food just because they are food sized and in their drift. Unless this secret fly looks like a something the fish know is not food, they are likely to eat it.
So, throwing something new to trout is key. For example, every fish quickly learns to avoid a San Juan Worm. Recently, a friend showed me a SJW that noted angler Dan Trela had tied. There was an extra–and, very clever–detail that I’d never seen before. A friend landed a pig of a brown with that fly.
So, over time, I tie fewer types of flies (N.B.: my Top 3 Nymphs), but more variations of each one. What’s changed is I’m more greatly varying the sizes and colors of each fly.
Two examples. First, I love throwing the ol’ Frenchie. I tie the fly in various sizes, from #8 down to #18. I use different tungsten beads for each in order to be able to accommodate a river’s current. And, over time, I’ve accumulated a variety of pheasant tail colors to show something new to the fish: natural, brown, black, olive, orange, and yellow. I also vary the hot spot thread collars, too.
Second example. When mayflies are about to hatch, I will fish the WD-40, from sizes 14 down to 28, and, in a variety of colors. When I’m feeling industrious, I ahead of time will tie a flashback version. On each fly, I will put onto the thorax a single strand of flash and cover it with a drop of Loon UV Finish. Since some bugs use air bubbles to rise to the surface, I wanted to add a detail that would mimic a bubble on the fly.
For a long time, this fly absolutely crushed it at the Farmington. It did particularly well when fished on a rise, at the end of the drift, in front of a rock. So many fish pounced on those flies, more so than the “plain” WD-40.
That summarizes my new thinking on variant flies, a version 2.0, if you will. Throw something that the fish do not know yet is not food.
So, if you’re thinking of treating yourself this holiday season, I’d seriously consider getting into fly tying. It really has changed everything for me, and it has been fun to boot, particularly during the winter.
Also, am happy to announce that Noel Dawes will be joining our blogging team. Adam and I are excited to welcome him. He does many types of fishing and is clearly very experienced. Welcome, Noel!