Baetis Nymph for Fly Fishing

Everything You Need to Know About Baetis Nymph

I recently watched a video of trout feeding. They seemed to grab tiny morsels drifting downstream. I got me thinking about how productive Baetis flies are and that tiny flies most likely make up a huge part of a trouts diet.

Nymphing is more effective than most fly fishing styles, we’ve all heard the adage about how trout feed mostly on nymphs. Let me help explain everything you need to know about Baetis nymph.

Baetis is a mayfly’s genus belonging to the Baetidae family, commonly referred to as the blue-winged olive. (BWO) Baetis nymphs are the most widely distributed nymphs on the planet, with a wide variety found in North America, which is why they are an excellent option for fly fishing.

Baetis and BWO nymphs are a perfect fly when bugs are hatching, BUT you’re not seeing fish rise. Let me help you learn everything you need to know about the Baetis nymph and the best patterns to try.

RS2 Emerger in size 20
RS2 Emerger in size 20 – photo credit UMPQUA

What is Baetis Nymph?

Baetis, also referred to as the Blue-winged olive to most anglers, is one of the most widely distributed insects on the planet. There are currently over 150 discovered Baetis species globally; plus, their tiny bodies make them the best bait to imitate for fly fishing.

Over the last decade, a significant taxonomic improvement has occurred in this group. Baetis nymphs have a maximum length of about 10mm, and this doesn’t include some of them that come with two tails. (source)

Guide Tip: Check out this article where I unravel everything about Blue Wing Olive (Plus Fishing Tips)

The fact that they are the first insects to hatch every season works perfectly for anglers. These insects tend to breed on a wide range of water bodies, from streams and lakes to water butts and ditches. Plus, their nymphs are exceptional swimmers that love feeding on algae. So they serve as the primary source of food for some fish species every season. (source)

Why Are Baetis Nymphs the Best Baits for Fly Fishing?

Baetis nymph is one of the best guide flies in the market. It is easy to tie, durable, and realistic. It can consistently fool trout or other fish on any spring creek, lake, river, or tailwater throughout the United States. Baetis nymph patterns work perfectly in water bodies with dense to moderate Baetis nymph populations.

Therefore, if you live near a water source filled with a wide range of fish species, then you need the right bait. Dry fly that resembles the insects found in that river or lake. Unfortunately, many patterns have come and gone. However, for over 20 years, the Baetis nymphs are still the most popular among anglers. And that is because it can fool a wide range of fishes under a wide array of conditions. (3)

The Baetis are multi-brooded insects, plus their most excellent emergence always takes place in fall and spring. Therefore, you can find different sizes of these insects in plenty in most of the world’s water bodies regardless of the season. The Baetis nymphs can be seen moving around in plenty at the base of the lake, relocating or feeding at dawn or dusk.

Entomologists refer to this as behavioral drift, but even a tiny flow can dislodge the nymphs from some substrates, which they refer to as catastrophic drifts.

Either way, any form of drift can result in a considerable population of nymphs swimming, resulting in more trout. (source)

Therefore, understanding the drift can help improve your likelihood of catching something. In fact, your Baetis nymph pattern will catch something every time you cast your line.

But you may have to adjust the weight of the fly in order to get it to the correct position.

Plus, when the trout are fully engaged on these nymphs, they tend to be very active and more focused.

So, you must use the right color, shape, and size of mayfly nymphs to get their attention. After all, they will ignore any less enticing offer being presented to them by the fly anglers. (source)

Therefore, understanding their behavior and when they are more active can increase your chances of catching something. It will also help you design the correct Baetis nymph pattern for your next fishing trip. After all, the right color, design, and shape can make a huge difference.

What Are the Best Baetis Nymph Patterns for Fly Fishing?

As aforementioned, Baetis nymph patterns have been there for decades. And in those years, numerous fly anglers have created different Baetis nymphs that have changed their fishing experience. So here are some of the best Baetis nymph patterns in the market:

1)   RS2

A considerable percentage of the fly anglers can attest that RS2 is a distinctive pattern that can capture more trout than the other flies combined. And that is because the RS2 is a more life-like pattern than a considerable percentage of the patterns in the market. The RS2 was developed over four decades ago by Rim Chun. The RS2 is an exceptional fly, but tying it can be pretty challenging. (source)

A Special Thanks to About Trout. Check James YouTube Channel – About Flies

This Baetis nymph pattern is available in a wide range of colors, including grey, olive, tan, and black. But we recommend that you get an RS2 Baetis nymph pattern with sparkling wings. You can also get a few with some white feathery wings.

2)   Juju Baetis

Juju Emerger Baetis Nymph for Fly Fishing
Juju Emerger Baetis Nymph for Fly Fishing – photo credit UMPQUA

Suppose you ever notice some grey emergers on the water surface. In that case, you should prepare to use your Juju Baetis Emerger. Juju Baetis is more than simply a Baetis nymph pattern; it is a reliable fishing tool that can guarantee you a catch every time. Plus, it is easier to make than the RS2 pattern. Thanks to its unique design, this is one sturdy fly that can capture several fish in a day. (source)

3)   2-Bit Hooker

Two Bit Hooker
Two Bit Hooker -photo credit UMPQUA

Despite its unique name, this Baetis nymph pattern is exceptional. Charlie Craven got this pattern right when he invented it the first time. After all, it is beautiful, sturdy, and can catch a wide range of fish. This Baetis nymph pattern features two bead heads, a segmented body, partridge feathery tail, some nice hackles, and a flashy back.

Some of the most common colors of the 2-bit hookers that have guaranteed folks success include olive, black, grey, red, and purple. But some folks have gotten better results with the red ones. (source)

4)   Barr’s Emergers XX

The Barr’s emerger is an exceptional imitation of the blue-winged olive and is loved by most anglers. The fact that they resemble the BWO is crucial because they are easily found in a wide range of stores.

Barrs Emerger Nymph
Barrs Emerger Nymph

Invented by John Barr’s in the mid-1970s, you can quickly get this unit without or with bead heads. This Barr’s emerger’s additional weight and flashy design can guarantee you more catch.

Plus, some anglers claim that this bead-headed emerger can perform better than those that don’t have a bead head. (source)

5)   Stalcup’s Baetis Nymph

Most folks concur that the Stalcup’s Baetis Nymph is one of the most beautiful patterns in the market. Most anglers rank up there in terms of quality with the Juju Baetis. In terms of catching fish, it can outperform most Baetis nymph patterns. (source)

6)   WD40 Baetis Nymph XX

Our list of the best Baetis nymph patterns will be incomplete without mentioning the WD40 Baetis Nymph. Initially designed by Mark Engler, the WD40 is relatively easy to prepare and works perfectly in small sizes.

WD40 a great baetis nymph pattern
WD40 a great baetis nymph pattern

This basic pattern has served me for a long time, and the fact that it’s easy to design means that it doesn’t have to mimic any specific Baetis species. But if you are looking for more success in your next fishing trip, I recommend that you purchase some flashy WD40 nymphs. A little flash can attract more fish. (source)

7) BWO Baetis Nymph

My home waters have a lot of smaller BWO hatches and the nymphs will be an olive green. The size of the nymph in the wild varies, but a size 18 to 20 hook matches up well. I’ll fish this below a dry fly like a Foam Yellow Sally.

BWO Emerger the perfect Baetis nymph
BWO Emerger the perfect Baetis nymph

Since this nymph isn’t weighted, you’ve got to give it a chance to sink. A trick I’ll often use is to grab some river bed sand and gently rub it on to the fly. This helps break the surface tension helping it sink.


How Do You Fish Baetis Nymphs?

Baetis nymphs usually are fished near the base of the river or lake. Since Baetis nymphs are great swimmers, there will always be something moving deep in the river; therefore, you have to cast deep if you plan on catching something. Plus, you can fish any day of the season; you don’t have to wait for them to hatch.

What Do Juju Baetis Imitate?

Juju Baetis nymph is a unique pattern that resembles the blue-winged olive (BWO). This nymph pattern is a perfect imitation of the real Baetis Nymph. It is pretty standard in the Colorado River system.

What are Baetis Nymphs?

Baetis nymphs, commonly referred to as BWO or olives to most anglers, are the first insects to hatch every season. They usually start emerging from late February to April and can keep the fish fed all year long while making it easy for you to fish.

Guide Tip: Learning about the bugs that catch fish is a way to demystify this fly fishing thing. Read – Fly Fishing Entomology – Bugs that Catch Trout


Baetis nymph is one of the most common ephemeropterans in the water, serving itself as food for the fishes. These nymphs are the first to hatch, and they are about all season long. And this makes the Baetis nymph patterns the best option for fly fishing. Plus, available fly anglers get spoiled for choice with the many designs. 

Are you looking for some great How To Fly Fish Articles? Checkout this list:

Hi David Humphries Owner of Guide Recommended. I love everything to do with fly fishing. Casting, Tying, YouTube, writing about it and even teaching. I’ve got a FREE video workshop teaching how to dry fly fish at this link How to Fly Fish


  1. Wikipedia contributors, Baetis, Accessed January 16, 2022
  2. Wikipedia contributors, Baetidae, Accessed January 16, 2022
  3. Pat Dorsey, Tying and Fishing Tailwater Flies, Accessed January 16, 2022
  4. YouTube contributor, RS2 Accessed January 16, 2022
  5. YouTube Contributor, Two Bit Hooker Fly Tying Instructions and Directions – Charlie Craven Accessed January 16, 2022
  6. YouTube Contributor, Juju Baetis Fly Video Instruction- Charlie Craven’s Jujubaetis, Accessed January 16, 2022
  7. YouTube Contributor, Barr’s Emerger BWO, Accessed January 16, 2022
  8. Pat Dorsey, Colorado Guide Flies: Patterns, Rigs, & Advice from the State’s Best Anglers & Guide, Accessed January 16, 2022
  9. YouTube Contributor, WD40 – Simple and Effective Nymph Fly Pattern – McFly Angler Tying Tutorials, Accessed January 16, 2022
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