Double up on drys.
A very effective method of fly fishing is to fish a dropper rig, two nymphs at the same time or a dry fly with a nymph hanging underneath it. It stands to reason that presenting two flys at the same time increases the chance of catching fish. Typically, the flies are at different levels in the water column and offers a choice to the fish.
An often overlooked method of fishing a dropper rig is using two dry flys on a dropper rig, especially when your not sure exactly what fly the fish are feeding on. This allows you to offer the feeding fish several options in fly type and sizes. It also allows for you to fish a small dropper fly such as a hard to see BWO, ant or midge emerger pattern using the first fly as a strike indicator. Its not a bit unusual to find fish feeding on the surface, that will come up to your fly and then refuse to take it. Lets face it, fishing small flies, especially in fast moving water isn’t easy. Its hard to see your fly and we tend to feel that it is hard to attract attention from the fish with a small fly.
During the spring mayfly period one of my favorite combos is an Adams parachute in a size 12 or 14 for the first fly, on 5x tippet. Then I will tie 12 to 16 inches of 6x tippet onto the hook bend and a size 18 blue wing olive or ant pattern. The Adams is a great generic fly pattern for a lot of our spring time mayflies and is also a good floater. I also make sure the Adams stays on the surface and I keep it well dressed with powered floatant. The small olive and ant patterns are a standard on all of our trout streams. I can’t tell you how many times I have seen a trout come up to the Adams, refuse it and then turn and take the smaller fly.
This is also very effective during terrestrial season. A small beetle or ant dropped behind a hopper pattern is super effective.
When fishing these two dry rigs I consistently catch the majority of the fish on the smaller, dropper fly. The next time you find fish feeding on the surface that are giving you a hard time, give this a try. It just might turn a frustrating experience into an eye opening experience!