Dark Skies Fly Fishing

Dark Skies Fly Fishing logo

Fly Fishing in Pennsylvania, New York, Ohio, West Virginia, Maryland, and New Jersey

How to Fish and Tie the Baeties Emerger Cripple

Baetis Emerger Cripple Fly

If a fly is small and olive, it’s often affectionately referred to by anglers as a BWO, or Blue Wing Olive. BWO is an acronym often used interchangeably with Baetis. However, there are approximately 150 species of mayflies that fall under the genus Baetis, and the BWO represents just a fraction of them. There can be so much variation in this insect from stream to stream and species to species that it would require multiple boxes of flies to imitate whatever variation you happen to encounter. Fortunately, there’s the Baetis Emerger Cripple, which matches so many of these species that it has become my hands down favorite pattern for matching the Baetis (BWO) hatch wherever I happen to encounter them. 

Part of what makes the Baetis Emerger Cripple so effective is that it includes all of the general characteristics of the genus. It’s small, has a hint of olive, a vague body, and perfectly represents a natural struggling to break free of its nymphal shuck. That last part is most important because small flies, smaller than size 16, often struggle to break through the water’s surface tension to emerge as adults, and so they get caught in the film.

A quick note about surface tension. Imagine a thin layer of plastic covering the surface of the water. As air temperatures cool, that layer gets thicker. The thicker it gets, the harder it is for mayflies to cleanly break free and emerge as adult duns. Many flies that are either very small or very big often have a hard time to breaking through that film – or plastic, if you prefer. Considering that most Baetis fall into the “very small” category, you can hopefully see why fishing an emerger version of this pattern in the film might be most effective. When stuck in the film, they become easy targets for trout.

Overall, Baetis are great swimmers. However, like many mayflies, when they begin to emerge, a gas bubble forms around their bodies and they rise to the surface. Once in the film, they shed their nymphal shucks to emerge as full-fledged adult duns. However, a percentage of the emerging insects never reach the dun stage. For any number of reasons, they become damaged as they shed their shucks. For instance, a wing may not emerge cleanly or end up deformed enough that the insect cannot take flight, or a trout may have slashed at it as it ascended the water column, and so it also gets stuck in the surface film.

When to Fish the Baetis Emerger Cripple

Baetis can be difficult to identify in the air, mainly because they’re so small, but also because of when they tend to emerge. They’re known to hatch on dark, dreary, rainy days. Their darker bodies and bluish, slate-colored wings (depending on the species) can make them very hard to see. During a Baetis hatch, it’s common to see trout feeding all around you and yet not be able to identify what they’re eating without closely inspecting the water’s surface. In these instances, a pocket seine really comes in handy and will allow you to collect a sample so that you can match the exact stage of the insect that fish are keying on.

If you cannot collect a sample, note how the fish are rising to feed. Trout taking bugs in the surface film will often create barely more than a dimple on the water’s surface. I’ve found this to be especially true with trout feeding in slower water.

Mayflies tend to emerge in the riffles, where the surface tension is more broken, and trout feeding there tend to be more aggressive. A high-riding dun is a good option for fishing the riffles at the head of a pool during a hatch. However, further downstream, in the slower parts of the pool, the fish can be feeding exclusively on bugs trapped in the film. I’ve seen this happen more times than I can count, and it can make matching the hatch frustrating. Just when I think I have the trout figured out, I start working downstream through the slower water and have little success. These are usually the times I tie on a Baetis Emerger Cripple.

Here's a video about fishing the Baetis Emerger Cripple during a hatch on First Fork Sinnemahoning Creek.

How to Tie the Baetis Emerger Cripple

The Baetis Emerger Cripple looks more complicated to tie than it actually is. Although it seems to have a lot going on, it’s the size of the fly (very small!) that presents the biggest challenge. As you’re tying this pattern, remember that sparse is best. This is an easy pattern to make too bulky simply because it contains multiple ingredients. The key is to use each ingredient sparingly and pay attention to proportions.

Start by clamping a size 16-22 dry fly hook in your vise. I’ve seen this pattern tied on scud hooks, too, but usually I just tie it on any standard dry fly hook. 

Attach 12/0 black thread to the hook shank starting about two-thirds of the way up the shank and stopping about in line with the barb of the hook. Next, use 3 fibers of pheasant tail to create a tail approximately one to one and a half hook gaps in length. 

Start by tying in three pheasant tail fibers for the tail.

At this point, you can clip off the butts of the pheasant fibers and tie in two to three new fibers by the tips at the base of the tail. Pheasant tail is thin and brittle near the ends, which is important to keep bodies thin on small flies. If I’m tying this pattern on a larger size 16, I’ll often just wrap the original three fibers up the hook shank and not tie in the new ones. More often, though, I’m tying this on a size 20, the most common size I use for this pattern.

Occasionally I’ve seen this pattern offered with an extra small gold rib over top of the body, but that’s unnecessary. The theory is that the rib will make it more durable, which it does, but not enough to warrant the extra bulk or extra step tying it. Just my opinion. I also don’t like adding it because I don’t want any sparkle of any kind on this fly. I want it to appear small and drab, like a real Baetis.

Tie in three more pheasant tail fibers by the tips to wrap the body.

Wrap the pheasant fibers approximately halfway up the hook shank, secure, and trim. Next, dub a thin noodle of olive dubbing onto the tying thread and create a small thorax. 

fly tying small beats
Dub a small thorax with dubbing and color of your choice. Keep this small and sparse, especially on patterns smaller than size 16.

Next, tie in some grizzly or olive-grizzly hackle of a size proportionate to the hook. In this case, I like the hackle to be about one and a half hook gaps wide. Make a couple turns of hackle, secure, and trim. For matching other hatches, try tying this pattern with yellow or orange as well as blue dun colored hackle.

dry fly beatis emerger cripple
Hackle should also be fairly sparse on very small versions of this pattern. I mainly use grizzly or olive grizzly hackle, but I also have great success with yellow-orange and dun colored hackle.

The crippled wing is created with a small stack of elk hair. Clip a tiny bunch and place it in your hair stacker and give it a couple gentle taps to align the tips. Remove carefully to keep the tips aligned and place on top of the hook, just behind the eye and pushing down on the hackle and thorax. The wing should be approximately one hook gap in length and extend straight out over the eye of the hook. Make a couple loose wraps to gather the hair and then a couple of tighter ones to secure it. 

fly tying beatis emerger
Secure the elk hair with a few loose wraps of thread and then make a couple of tighter ones to keep it in place.

Pull the wing up and back and make a few wraps under the hair behind the hook eye and whip finish. To finish the fly, trim the butts of the elk hair so that they are approximately in line with the back edge of the dubbed thorax.

Baetis Emerger Cripple Fly
This simple pattern is deadly for all types of Baetis hatches.

Possible Variations

The Emerger Cripple is a style of fly that can be modified for almost any species of mayfly. To imitate Blue Quills (another common species of Baetis), use dark hares ear for the dubbed thorax and a darker shade of elk hair for the crippled wing. For small Sulphurs, try orange or pale orange dubbing for the thorax. 

Although I’ve never used this style of fly larger than a size 16, I’m sure it would work well for matching the crippled version of almost any mayfly species. The only thing I’d change on larger imitations is that I’d opt for the curved, scud-style hook rather than the straight shank standard dry fly hook. This would add a little life to those larger patterns where the details are more visible. I’m not sure those little details matter quite as much on size 20 and smaller as long as you’re matching the size, color, and stage of the hatching insect. Besides, the general shape of the material on the hook often gives a fly that tiny a realistic shape.

Baetis emerger cripple
The profile of this Baetis Emerger Cripple just too realistic for a trout to pass up!

Advantages of Fishing the Baetis Emerger Cripple

I’ve already discussed when I use this pattern, such as when trout are keying on the emergers rather than the dun stage of the Baetis. But what I enjoy most about this pattern is that it’s incredibly visible for such a small fly. I credit the elk hair wing for that. Also, that wing allows it to float extremely well while also keeping a low profile. That might sound paradoxical. After all, how can something be visible and yet have a low profile? Part of the reason is that the fly rides on its side on the water’s surface. It lies almost flat on the water, and even with a straight, standard dry fly hook, the elk hair wing is quite visible and also gives it a slightly curled look that’s extremely realistic to that of an emerging mayfly. 

Because it floats so well, it can be fished for longer periods of time without needing floatant reapplied. Even after a catch, I often swish it in the water to rinse off any fish slime, make a few false casts, and the fly is usually good to go. When it does start to sink, I use a desiccant type floatant to draw the moisture form the fly and keep on fishing.

Another thing I like about this pattern is that, because it’s such a strong floater, I can usually get away with a tippet one size larger than I’d normally use with a size 20 pattern. I can get away with a 5x tippet instead of dropping down to 6x — however, if the water is low and clear, or I’m fishing over finicky trout, 6x is my first choice for tippet, and I’ll drop down to 7x if things get really tough.

Baetis are prolific mayflies found on many streams across the country, if not the world. With approximately 150 species that fall under the Baetis genus, it’s likely you’ll eventually encounter at least one of them on your favorite stream. And often, no matter where or when I encounter this fly, the Baetis Emerger Cripple is typically the first pattern I reach for to match the hatch.

Did You Find This Article Helpful?

Stay up to date with the Dark Skies Fly Fishing monthly newsletter for free and receive the latest posts in fly fishing news, tricks, tips, and techniques, stream reports, as well as updates on new flies added to the Online Store and exclusive discounts!

Sign Up Now

Have a fly fishing question you’d like answered? Drop us a line at info@darkskskiesflyfishing.com! If we use your question in a blog post or in the newsletter, we’ll send you a FREE fly box with a dozen of our favorite nymphs and dry flies!

Save 25% on your next order!

Use the promo code 25OFF at checkout

Shop Now

Leave a Comment

Your email address will not be published. Required fields are marked *

The maximum upload file size: 50 MB. You can upload: image, video. Links to YouTube, Facebook, Twitter and other services inserted in the comment text will be automatically embedded. Drop files here

Scroll to Top