On the fly: Skip nymphs, use emerger flies

With spring quickly approaching, it’s time for anglers to prepare their fly boxes for matching a few more hatches.

Baetis — also referred to as Blue Winged Olive mayflies, Caddis and Stonefly nymphs — are readily available for fish to eat from late February through June. Today, I’m sharing my favorite Baetis patterns, and the best conditions in which to use them.

A Blue Winged Olive’s life cycle has three major stages: nymph, emerger and adult.

The nymph stage is probably the most imitated by anglers and, ironically, the least important. Nymphs spend their time living on the bottom of the river, so trout aren’t conditioned to seeing them. This means that the best time to use a Baetis nymph is after an increase in water flow. A bump in flows will stir up the bottom, causing the nymphs to get swept high in the water column and leaving them exposed for fish to eat. Popular nymph patterns are the Juju Baetis, Stalcup’s Baetis nymph, the Pheasant Tail nymph and the Bead Head Hare’s Ear nymph.

The emerging stage of the Blue Winged Olive is the most important to imitate because they are exposed to the fish. When Baetis nymphs reach maturity, they emerge off the bottom toward the surface by swimming and using trapped air bubbles to float. When they reach the surface film, they shed their nymphal shuck much like a butterfly breaking free from it’s cocoon.

This is when the Blue Winged Olive is most exposed, and hungry trout take advantage. Once they’ve reached the surface, they stretch out and dry their wings so they can take flight as adult insects.

My favorite fly patterns for imitating emergers are both creations from famous Colorado tyers. Consider the true importance of this stage of the hatch to anglers wanting to catch fish, and it’s a safe bet to say that you should have these in your fly box. Rim Chung created the Rim Semblance No. 2 — commonly referred to as the RS-2. This fly is easily the most popular emerger in the country, and for good reason. The next fly is a creation by John Barr called the Barr’s Emerger.

Great adult dry fly imitations are the Parachute Adams and the Barr’s Vis-a-dun. If fish are eating on the surface, these dry flies tied in smaller sizes are my go-to. Try using them at the peak of the hatch when the most bugs are on the surface.

The best Blue Winged Olive hatches tend to happen during calm, slightly overcast days, but Blue Winged Olives can hatch at any point during the spring.

Early spring success using this hatch can be found by those who come armed with flies imitating all three stages of the hatch, and by keeping a close eye on the weather and water conditions.

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Kleis is a Colorado Springs native and professional fly-fishing guide for Angler’s Covey Fly Shop. Read his columns on the third Thursday of each month in Out There. To schedule your fly-fishing adventure, email jonkleisflyfishing@yahoo.com.