Early Season Flies for Colorado

The month of May and June can be a challenging time for anglers. High winds, drastic temperature variances, and high water caused by sudden snow melt all combine to make fishing with a fly rod harder and more unpredictable. These tough conditions cause many fishermen put their rods away for a few weeks during spring runoff, but often times those who weather the storm and fish in the swift, cold, muddy waters of spring and early summer are rewarded with healthy, strong-fighting fish.


Many years, the emergence of the super-sized Pteronarcys Californica is the most anticipated event of the fly fishing season on the upper Colorado River. These giant stoneflies migrate to the rivers edge by crawling along the rocky river bottom before beginning their airborne reproduction process. Anglers typically begin to notice the presence of salmonfly nymphs beneath large, porous rocks within inches of the river’s edge in fast riffles as the water temperature rises closer to 50 degrees Fahrenheit. With the sudden increase in available food, the trout gorge themselves on the salmonflies. For fly fishermen, this is a hatch not to miss, even when the river is raging and muddy. Effective patterns include black, brown, and orange Pat’s Rubber Legs, orange Stimulators, and Bitch Creeks in sizes 6 through 10.

San Juan Worms

The San Juan Worm is a trusted pattern among experienced fly fishermen everywhere. It has numerous variations and colors, but they all imitate the same annelids that can be found along almost every trout stream in the West. When the water is high, cold, and muddy, trout often see these worms as an easy meal and will eat them in the slow water against the banks. Pink, red, brown, and tan are the most commonly used colors for worms with the brighter ones working better in dark water and the more natural, subtle colors working better when clarity improves.


Big trout get most of their protein by ambushing littler fish that inadvertently expose themselves within the predator’s range. Fly fishermen who want to catch these trophy fish during the runoff season must often cast heavy, sinking streamers close to the banks from a raft or drift boat. Some of the favorite streamers here in Eagle County are black, olive, and tan Sculpzillas, black and olive Motor Oils, and yellow Platte River Spiders.

Blue Winged Olive Mayflies

Most of the mayfly hatches that we see here in the Rocky Mountain West occur during the summer months, but the multi-brooding Blue Winged Olives often show themselves as early as March in the Eagle, Colorado, and Roaring Fork rivers. Trout are constantly on the look out for these small morsels of food, and fly fishermen should be as well. Even when flows are up and the water is muddy, trout occasionally sip small BWO emergers and duns in foam covered back eddies close to the bank. Barr’s emergers, RSII emergers, and Parawulff BWO patterns work well in most BWO hatches.

Fly selection is often the easiest part of high water fly fishing. Weather, wind, and dangerous boating and wading conditions present the biggest challenges for anglers. If you plan on getting out on the water this runoff season, make sure to equip yourself with the proper flies and fly fishing safety equipment. Remember that these patterns are just a few of the hundreds of early season flies available. Visit the shop in Edwards to pick up all the patterns above and thousands more.

Andy “Otter” Smith, Guide and Content Writer