The dry dropper rig is a quick and great option when you are on the water and have fish rising occasionally but not fully committing to eating on top. This is also a great rig for when you have rising fish but expect there are other fish near that are not rising, yet. The dry dropper rig is also a quick and effective method for prospecting for fish or learning new water.
When you are ready to set up a dry dropper, simply tie on a large dry fly to your leader. The large dry fly can be a size 10-12 chubby or size 12-14 adams to start with. The dry fly may be eaten by a fish but is also acting as an indicator for the fly you will have trailing off. If you are confident in your bug identification, you can use the dry fly you see fit for what is hatching.
Treat dry fly is with desiccant. This can be FlyAgra, Gink, or your personal preference of floatant. Make sure to treat it well!
Using a clinch not, tie tippet to the bend of the hook on your dry fly. Typically, we like to use fluorocarbon tippet as it is a bit denser than nylon, so it has a slight sink rate. Beyond that, fluorocarbon is virtually invisible to fish and should be utilized subsurface as much as possible. When rigging off your dry fly, use the tippet size to match the fish you are fishing for. After
After tying on a tippet to the bend of the hook, it is time to decide on the right depth of the dropper. In Central Oregon trout waters, fishing 14-16 inches under your dry fly is common. However, if you are utilizing the dry dropper on a lake, try to see where the fish are feeding subsurface. You may end up fishing 14 inches up to 48 inches under the dry fly when lake fishing.
After selecting your length, trim off tippet. Connect your nymph/emerger to the free end of the tippet utilizing a clinch knot. Nymph selection will be area specific. If you see fish eating emergers and can identify that, fish emerger patterns. However, if you are scouting/prospecting new water fishing a copper john, pheasant tail, or hares ear can prove to be effective.
Fish it! If you are fishing a dry dropper on the river, cast upstream and let the flies float down the current to where you see feeding fish or where you suspect fish to be feeding at. Try to get a long drift so the nymph/emerger has time to get into the trout feeding zone. If you see that fly dip, stop, or hesitate, SET THE HOOK! Remember, be prepared for takes on the dry as fish may be looking up and ready to demolish that dry as it drifts over.
If you are fishing on a lake, you should cast towards feeding fish. If you are fishing a dry dropper rig, you have a decent understanding of where fish may be cruising or staging for feeding. This is where your depth may differ drastically over river fish. A general rule of thumb, see a rising fish or two, CAST to the rising fish.