Baetis Fly Fishing Patterns You Need to Try

In this guide, we’ll delve into everything you need to know about Baetis patterns. We’ll start by exploring what makes these mayflies unique, then share the top 11 Baetis fly patterns you need in your box. Finally, we’ll cover techniques to fly fish Baetis effectively, ensuring you’re prepared for any situation on the water.

What is a BWO or, blue wing olive, or Baetis?

BWO is short for Blue Wing Olive, a common term for mayflies in the Baetis genus. These mayflies are ubiquitous in freshwater ecosystems, thriving in rivers, streams, and even some stillwaters. Recognizable by their olive-colored bodies and pale bluish wings, Baetis are a favorite prey of trout due to their abundance and lifecycle variability.

Lifecycle of Baetis

Baetis mayflies have a four-stage lifecycle:

1. Nymph: The immature underwater stage where Baetis live on the riverbed.
2. Emerger: The transition stage is when nymphs rise to the surface to hatch.
3. Dun (Adult): The winged adult that rests on the water before taking flight.
4. Spinner: The final stage, where adults return to the water to mate and die.

Each stage provides feeding opportunities for trout, making it crucial for anglers to have patterns that mimic all phases.

When and where to fish Baetis

Baetis hatches are most prevalent during cooler months, particularly in spring and fall. These insects thrive in clean, well-oxygenated water, meaning you’ll find them in tailwaters, freestone rivers, and spring creeks. Their small size, ranging from #16 to #24, makes matching the hatch with accurate imitations a must.

11 Best Baetis Patterns

RS2

The RS2 Baetis is a fly fishing pattern called the "RS2," created by Rim Chung. This design closely resembles an emerging Baetis mayfly, a small and common species. Renowned for its effectiveness, the RS2 is particularly successful in enticing selective trout, especially in Western rivers. Its simple yet lifelike design allows it to adapt to various stages of the Baetis hatch.

Key Details About the RS2 Baetis:

Origin: The "RS" in RS2 stands for "Rim's Semblance," a nod to its creator, Rim Chung.

Imitation: The fly is specifically intended to mimic the emerging stage of the Baetis mayfly.

Key Features: Characterized by a small body and a wing that sits just above the water surface, the RS2 is often tied using materials like CDC (Cul de Canard) or Antron yarn for the wing and simple dubbing for the body.

Versatility: While it excels during Baetis hatches, the RS2 can be customized in color and materials to imitate other small emerging insects, making it a versatile addition to any angler's collection.

JuJu Baetis

The "JuJu Baetis" is a small, lifelike nymph fly pattern crafted to mimic the Blue Wing Olive (BWO) mayfly. Developed by renowned fly tyer Charlie Craven, this pattern is highly regarded in trout fishing due to its slender profile and realistic design. It incorporates materials such as "Super Hair" to create a segmented, natural-looking body.

Key Details about the JuJu Baetis:

Purpose: Represents the Blue Wing Olive (BWO) mayfly

Notable Features:

• Slim, streamlined body
• Segmented appearance achieved with "Super Hair"
• Optional partridge feather tail
• Available in various colors to suit different water conditions

This fly is celebrated for its effectiveness and versatility on the water.

Rainbow Warrior

The Rainbow Warrior Baetis is a fly fishing nymph designed to mimic a Baetis mayfly nymph but stands out due to its eye-catching features. With a pearl tinsel body, red thread accents, and often a tungsten bead, this fly is highly effective in drawing trout's attention, especially in tailwater conditions. Created by Lance Egan, this vibrant pattern is known as an "attractor" fly for its ability to entice strikes even in challenging situations.

Key Features of the Rainbow Warrior Baetis:

Design: The fly showcases a pearl tinsel body, a red thread hotspot near the bead, and a tail made of pheasant tail fibers, giving it a highly reflective and striking appearance.

Creator: Lance Egan, a skilled fly fisherman from Utah, is credited with developing this innovative pattern.

Best Application: Commonly used as a dropper fly in nymph rigs, it excels in tailwater settings where trout can be particularly selective.

Purpose: While it can resemble aquatic insects like midges or mayfly nymphs, its primary role is to draw attention with its bright and flashy design rather than serve as an exact imitation.

This versatile and bold pattern has become a favorite among anglers for its effectiveness and unique appeal.

Barr’s Emerger

The Barr’s Emerger is a versatile fly pattern designed to mimic a mayfly nymph or emerger, particularly during the early stages of a hatching blue-winged olive (BWO) or baetis mayfly.

Key Details of the Barr’s Emerger:

What it is: A straightforward and effective fly, ideal for various fishing conditions, but particularly productive during BWO or PMD hatches.

How to use it: The Barr’s Emerger can be fished as an attractor or used as a dropper in a tandem nymphing setup. Its bead weight makes it suitable for trailing behind a dry fly.

When to use it: It is best used at dawn or dusk, during times of rising fish activity, or even when surface activity is minimal.

To create a Barr’s Emerger, you’ll need the following:

1. Hook: 2X-short emerger hook, sizes 18–24
2. Thread: Dark brown, 16/0 Veevus thread
3. Tail/Shuck: Brown or ginger hackle fibers
4. Body: Olive beaver dubbing
5. Wingcase/Legs: Wood duck fibers
6. Thorax: Natural beaver fur

This simple yet effective pattern is a staple for fly fishers and a reliable choice for enticing fish during hatches or subtle feeding activities.

Flashback Pheasant Tail

The Flashback Pheasant Tail Baetis is a nymph fly pattern designed to mimic a mayfly nymph, making it an effective choice for catching fish. This traditional Pheasant Tail nymph variation is particularly useful in various fishing conditions. Ideal for fishing as an emerger, it resembles the Baetis mayfly during a hatch.

Key Features of the Flashback Pheasant Tail Baetis:

Air Pocket Imitation: The tinsel on the fly mimics the air bubble aquatic insects use to ascend to the surface, creating a lifelike shine.

Quick Sinking: A tungsten bead ensures the fly sinks rapidly to the desired depth.

Eye-Catching Flash: The added flash grabs trout's attention, increasing its effectiveness.

Versatile Sizing: This pattern can be tied in various sizes, from 12 to 22.

To create a Flashback Pheasant Tail, you’ll need the following:

1. Hook
2. Thread
3. Pheasant tail fibers (for the tail and abdomen)
4. Medium Wapsi Pearl Tinsel (for the wingcase)
5. Peacock herl (for the thorax)
6. Additional pheasant tail fibers (for the legs)

This fly combines classic design elements with subtle enhancements, making it a versatile and reliable choice for anglers targeting trout during a Baetis hatch.

WD-40 Nymph

The WD-40 Nymph is a minimalist pattern with a sparse, natural appearance. This fly excels in spring creeks and other waters where trout are highly selective. The WD-40 is a versatile fly pattern that resembles Baetis nymphs and midge pupae.

Key Details of the WD-40 Nymph:

Origin: Created by Mark Engler, a guide at Duranglers in Southern Colorado, the WD-40 was developed to imitate emerging Baetis mayflies commonly found on rivers like the San Juan and Roaring Fork.

Appearance: This fly features a slender body made of thread, a barred tail and wingcase crafted from mallard, and a thorax made with dubbing. It comes in various colors, including black, olive, gray, and chocolate.

Uses: The WD-40 can be fished in multiple styles, whether as an emerger, nymph or swinging. It's effective when fished at the bottom with added weight or used as a dry emerger treated with floatant.

Best Seasons: This pattern shines during early spring and fall, aligning with the peak activity of Baetis mayflies.

Ease of Tying: With a straightforward design and minimal materials, the WD-40 is beginner-friendly and simple to tie.

Variations: A notable variation is the WD-50, which incorporates flash and wing buds for added attraction. This fly remains a go-to option for anglers targeting Baetis hatches and offers excellent versatility on the water.

Spanish Bullet - Olive

The "Spanish Bullet - Olive Baetis" pattern is Euro Nymph style fly designed to imitate the Baetis mayfly nymph, particularly in an olive color. Known for its streamlined shape and heavy weighting, this fly excels in Euro nymphing techniques due to its ability to sink quickly and reach the bottom of the water column. Its realistic design effectively mimics the small, natural Baetis nymph.

Key Features of the Spanish Bullet - Olive Baetis:

Design: Typically tied on a jig hook with a slotted tungsten bead to achieve rapid sinking. Features a tail made from "Spanish Coq de Leon" fibers for lifelike movement. The body is colored to resemble the olive hue of a Baetis nymph.

Application: Ideal for Euro nymphing, where the fly is fished near the riverbed. It can also be used as a dropper fly beneath a dry fly for versatility in different fishing setups.

Coloration: The olive color closely matches the natural appearance of Baetis mayfly nymphs, increasing its effectiveness as an attractor.

This pattern is a reliable choice for anglers targeting fish in rivers and streams, particularly in scenarios that require precision and quick sink rates.

Baetis Vis-A-Dun #22

This dry fly pattern effectively imitates a Baetis dun. Its upright wing and realistic proportions make it a must-have during active hatches. The "Baetis Vis-A-Dun #22" is a dry fly pattern crafted to mimic a small Blue Winged Olive (BWO) mayfly, specifically from the Baetis species. This pattern's visible poly yarn wing is a standout feature, designed to make it easier to spot on the water. This fly, tied by renowned fly tyer John Barr, features a hook size of #22, which is ideal for imitating smaller mayflies.

Key Features of the Baetis Vis-A-Dun:

Design: Modeled after a traditional thorax-style dry fly but enhanced with an upright poly yarn wing, improving visibility for anglers on the water.

Purpose: Designed to represent small BWO mayflies, it is particularly effective during hatches when trout are focused on these emerging insects.

Origin: Credited to fly tyer John Barr, the fly is often referred to as "Barr's Vis-A-Dun" in his honor.

Last Chance Cripple - BWO

Designed to mimic a crippled Baetis, this pattern is highly effective when trout are keyed in on vulnerable insects. The trailing shuck and lifelike body make it a standout option. The Last Chance Cripple - BWO Baetis is a fly pattern created by Rene Harrop, designed to mimic a Blue Wing Olive (BWO) mayfly—specifically a Baetis species—in the process of emerging.

Key Details About the Last Chance Cripple - BWO Baetis:

Designer: Rene Harrop

Imitates: A partially emerged, struggling Blue Wing Olive (BWO) mayfly, particularly of the Baetis species.

Notable Feature: Incorporates CDC (Cul de Canard) feathers for a delicate, lifelike wing profile.

Best Use: It excels in conditions with selective trout feeding during mayfly hatches, especially in spring creeks such as Henry's Fork.

This pattern replicates a mayfly struggling to transition from its nymph stage, making it highly effective for targeting selective trout, especially during hatches when fish are more cautious. The name "Last Chance Cripple" reflects the fly's resemblance to an almost-emerged mayfly still trapped in its shuck.

Sparkle Dun

The Sparkle Dun is a classic emerger pattern that imitates a Baetis transitioning from the nymph stage. Its trailing shuck and buoyant design make it ideal for slower water. The Sparkle Dun Baetis is a fly pattern designed to mimic mayfly duns in their emerging or crippled stages. This versatile pattern is a favorite among dry fly anglers and fishing guides due to its effectiveness and simplicity.

Key Features of the Sparkle Dun Baetis:

Imitation: This fly represents mayflies at their most vulnerable phase, as they transition from the water’s surface to the full dun stage.

To create a Sparkle Dun Baetis, you’ll need the following:

1. Materials: Crafted using easily accessible and cost-effective materials, the Sparkle Dun Baetis typically includes:
2. Wing: Bleached coastal deer hair or early-season elk
3. Shuck: Rusty brown Darlon or Z-Lon
4. Body: Pale yellow superfine dubbing
5. Hook: TMC 100, sizes #14-22
6. Thread: UNI 8/0 in Light Cahill

Effectiveness: This fly is highly effective and beginner-friendly, making it an excellent choice for anglers of all skill levels.

Drift: The streamlined design ensures a natural and sparse drift on the water, enhancing its ability to attract fish.

Tracking: The deer hair wing provides excellent visibility, allowing anglers to easily track the fly during use.

The Sparkle Dun Baetis is a reliable and adaptable fly that’s both practical and efficient for dry fly fishing enthusiasts.

Comparadun BWO #16

The Comparadun is a simple dry fly with a flush-profile design, perfect for imitating Baetis adults. Its buoyancy and realistic appearance make it a reliable choice for picky trout. The Comparadun BWO #16 Baetis is a dry fly designed to mimic mayflies and caddisflies, making it an excellent choice for targeting selective fish.

Key Features of the Comparadun BWO #16:

Appearance: This fly features a 180-degree deer hair wing that sits low on the water's surface, a forked tail to create a lifelike silhouette and subtle, natural colors that closely resemble real mayflies.

Effectiveness: Known for its success with selective fish, the Comparadun BWO is a versatile and effective pattern. It’s often recommended as a great starting dry fly for tying and casting across streams and rivers.

Versatility in Use: By adjusting the size, body color, and wing color, the Comparadun pattern can replicate a wide range of adult mayflies. Its wing structure also makes it suitable for both dun and spinner stages.

How to fly fish a BWO

Fishing Baetis patterns successfully requires adapting to the stage of the insect’s lifecycle that trout are targeting. Here’s how to approach each stage effectively:

Nymphing techniques

When trout are feeding subsurface, nymphing Baetis patterns like the JuJu Baetis, WD-40, or Flashback Pheasant Tail is highly effective.

Setup: Use a strike indicator or Euro nymphing rig with a tapered leader. Add a split shot or use bead-head patterns to reach the strike zone.

Presentation: Drift your flies naturally with the current. Keep your line tight to detect subtle strikes.

Target Areas: Focus on riffles, seams, and runs where nymphs are actively drifting.

Emerger fishing

During a Baetis hatch, trout often feed on emergers in the surface film. Patterns like the RS2, Barr’s Emerger, or Last Chance Cripple excel here.

Setup: Use a floating line with a long leader. Apply floatant to keep your fly in the film.

Presentation: Cast upstream and allow the fly to drift naturally with the current. Watch for subtle takes.

Target Areas: Look for feeding trout near seams and the edges of slower pools.

Dry fly fishing

When trout actively rise to adult Baetis, dry flies like the Sparkle Dun, Comparadun, or Vis-A-Dun are essential.

Setup: Use a tapered leader and light tippet (5X or 6X) to reduce drag.

Presentation: Ensure a drag-free drift by mending your line. Cast slightly upstream of rising fish and let the fly drift naturally into their feeding lane.

Target Areas: Focus on slow-moving water where trout are sipping insects from the surface.

Final tips for fishing Baetis patterns

Timing is key: Baetis hatches often occur in mid-morning or late afternoon, especially on overcast days.

Match the size: Always carry patterns in a range of sizes (16–24) to match the hatch precisely.

Go light: Use a lighter tippet (5X–7X) to reduce drag and avoid spooking fish.

Adjust for conditions: If trout are ignoring your fly, switch between nymph, emerger, and dry patterns until you find what works.