May 25, 2022
By Pat Dorsey
On my home waters, nymph fishing is the most reliable method of catching trout, especially if you are willing to modify your tactics and techniques to suit a variety of circumstances. I use the hook bend of the point fly to add a dropper when I’m streamer fishing, but I get a better hook-up-to-landing ratio with nymphs when I use an eye-to-eye connection. This works better to keep the hook gap and point free from obstructions. This is especially noticeable when using small size 20 to 24 nymphs and midge patterns.
As a general rule, I use the larger fly as the point fly, and separate the flies with 12 to 14 inches of tippet. If you space your flies too far apart, you lose the effectiveness of the attractor fly. If you need to add weight, pinch split-shot to the tippet knot 12 to 18 inches above the point fly.
Here are a few of my favorite “guide rigs” I choose depending on water conditions:
Down & Dirty Flies
In the central Rockies, spring runoff begins late April and continues through mid-June. During this period, most freestone trout streams are high and muddy for several weeks—but that doesn’t mean you have to quit fishing.
A size 10 Chamois Leech trailed by a size 14 pink San Juan Worm catches fish when there is only a few inches of visibility. Many anglers shy away from fishing in dirty water, but I look forward to the peak of runoff. I seem to find the largest fish of the season, and often have the river to myself.
At the start of spring runoff, trout key on the abundant aquatic worms getting flushed from the substrate. I have observed cases where trout have worms hanging out of their mouths, yet they somehow found a way to eat my imposter fly. In cases like this, it’s never out of the realm of possibility to fish with two San Juan Worms.
The best strategy is to target the edges of the stream, focusing your efforts on the softer cushions and seams. Fish stack up in these soft margins while trying to escape the faster currents and debris in the main current. If you catch a fish in one of these soft spots, chances are good there are several more.
Skinny Water Flies
One of the toughest challenges we face annually is catching trout in low or slow-moving water. Skinny water may be the result of drought, lack of downstream irrigation demand (tailwaters), or the natural progression of the season. The lowest flows of the year are traditionally between October and March.
Trout in slow currents have the luxury of closely scrutinizing your flies, so large patterns are generally far less effective. I stay away from gaudy high-water flies like San Juan Worms, egg patterns, leeches, stoneflies, and flashy beadheads as they have a tendency to spook fish.
Fishing with two size 20 to 24 flies—one midge larva (or pupa) trailed by a Baetis nymph is often my best game plan on the tailwaters where I fish. I start with a 9-foot 5X leader and add 6X monofilament tippet. I also use 6X tippet to attach the dropper.
One of my favorite low-water rigs is a size 22 Mercury Midge trailed by a size 24 or 26 Chocolate Foam Wing Emerger. The Mercury Midge has a little bit of flash which can act as an attractor, but not so much flash that it spooks fish. Usually, the trout take the Chocolate Foam Wing Emerger in this situation—not because it’s a better fly but because the dropper always behaves more naturally in the current. By varying the size of the Chocolate Foam Wing Emerger, I can imitate both midge pupae and Baetis emergers, which are both common hatches during low water.
Bait & Switch
Riffle water requires a far different strategy than flat, slow water. Even in low-water seasons, there are riffles and pocketwater where tiny flies can just get lost. In this type of water, my double nymph rig is an attractor trailed by a smaller mayfly or midge imitation.
The attractor draws attention, but it still has to be something the trout are accustomed to eating. My attractor changes with the season. If it’s May, I use a caddis larva as my attractor. In July when the Green Drakes are emerging, I use a Green Drake nymph. On some waters at certain times of the year, my attractor is a scud, egg, or aquatic worm imitation. It captures the attention of trout that might not actually be feeding at that moment—but the right fly might help them develop an appetite.
The smaller dropper fly is based on obvious secondary hatches. For example, early in the morning, my dropper might be a midge larva, but midday, I switch to a Baetis or PMD nymph. In late summer, my dropper might be a drowned Trico when the fish are keying on sunken spinners.
I am convinced that the trout are attracted by the larger fly, but they eat the dropper fly because they feed on smaller food items most of the time, and the fly farthest from the weight drifts more naturally in the water.