EmergerintermediateRocky Mountain West
RS2
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Regional source directory
Rocky Mountain Fly Design
Matched on Rocky Mountain West, emerger flies, trout. Colorado tier and shop lead for Rocky Mountain trout, bass, and predator patterns.
Taos Fly Shop
Matched on Rocky Mountain West, emerger flies, trout. New Mexico/Southwest trout shop lead for Rio Grande, San Juan, Pecos, and high desert water.
Stillwater Fly Fishing Store
Matched on Rocky Mountain West, emerger flies, trout. Specialist stillwater source for balanced leeches, chironomids, and lake-trout logic.
Fly Fish Food
Matched on emerger flies, trout, midge. Strong technical tying and trout catalog coverage, especially nymphs, dries, and stillwater flies.
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Rim Chung created the RS2 on Colorado's South Platte River, and it remains one of the most effective emerger patterns in the West -- which is remarkable given that it is essentially thread, a tiny wing, and hope. The RS stands for 'Rim's Semblance,' and the semblance in question is a mayfly nymph caught between its underwater life and its brief airborne one. Trout find this transitional state irresistible, possibly because vulnerability is the oldest lure in nature.
Quick Facts
Where to Fish It
South Platte River
CO · Tailwater
Frying Pan River
CO · Tailwater
Missouri River
MT · Tailwater
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Related Reading
region guide
Rocky Mountain Trout: A River-by-River Guide
The Rocky Mountain West holds the finest trout rivers in North America. From the gin-clear tailwaters of Colorado to the sweeping freestone rivers of Montana, these waters offer everything from technical dry fly fishing to aggressive streamer hunting. This is your river-by-river guide to all of it.
seasonal playbook
The Spring Playbook: First Hatches to Full Send
Spring is the most dynamic season in fly fishing — water temperatures swing daily, hatches emerge in waves, and fish that have been dormant for months begin feeding with increasing urgency. This is your region-by-region playbook for fishing the awakening.
species science
How Trout See Your Fly: The Science of Color and Light
Trout don't see the world the way we do. They perceive ultraviolet light, detect motion through contrast rather than color, and see a dramatically different fly at ten feet of depth than at two. Once you understand their four-cone visual system, you'll never choose a fly the same way again.
hatch guide
Midge Fishing: The Tiny Flies That Save the Day
When every other hatch has shut down, midges keep trout feeding. From winter tailwaters to high-altitude stillwaters, Chironomidae are the most abundant insects in freshwater ecosystems. Learning to fish these tiny patterns unlocks twelve months of dry-fly and nymphing opportunities.
hatch guide
Emerger Patterns: Fishing the In-Between
Trout eat more insects during emergence than at any other stage. Emerger patterns — flies that imitate the critical moment when a nymph transforms into an adult in the surface film — are the most consistently effective dry flies in fly fishing. Here is the science and the technique behind fishing the in-between.
technique
Water Temperature: The Master Variable
Water temperature controls everything. Metabolism, feeding intensity, insect emergence, dissolved oxygen, where fish hold, and whether they'll eat your fly. Understanding thermal dynamics across freshwater and saltwater systems is the single most reliable way to predict fishing quality before you even leave the truck.
seasonal playbook
The Winter Guide: Cold Water, Warm Hands, Willing Fish
Winter separates the dedicated from the fair-weather crowd. The rivers are empty, the hatches are tiny, and the fish feed in slow motion. But they do feed — they have to. And the angler who understands cold-water metabolism, midge biology, and the art of slowing down will find winter fishing not just productive but deeply rewarding.
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