Fly of the Month: Thorax Blue Wing Olive

Steve Parrott is our featured tier this month with a fly that is known for its simplicity for those who like to tie, and for its effectiveness for those who like to catch fish.

This variation of a classic blue wing olive sits low in the water, creating just enough of a different profile to make it what Steve calls a real “killer” fly.

Steve should know. He was a top competitor last year battling for a spot on the Fly Fishing Team USA. You can also find him most days in the office at the Blue Quill Angler and occasionally sneaking off to one of his favorite spots over on Clear Creek.

He describes this fly as great for spring and fall tailwater fishing because the bottom hackle is clipped off, causing it to ride low in the water. That helps it fool the pickiest of trout. For our purposes, he says, “it’s super easy to tie and a must have for every tailwater dry fly angler.”

Our ETU members certainly love the BWO, because on their list of the “must have” flies to fish Colorado streams,it ranked number 6. The BWO is usually fished small as an adult Baetis or other mayfly pattern. And while known as one of the first flies we turn to when we see something other than a midge hatch in early spring, it can be fished pretty much year around.

Watch for a rising fish and make your cast. There are few things as pretty in fly fishing.


Hook: Dai-Riki 310 or Tiemco 101, #18-22
Thread: Olive Dun 8/0
Tail: Dark dun hackle feathers
Body: Blue Wing Olive color Superfine Dubbing
Wings: Dark dun hackle tips
Hackle: Dark dun saddle or neck hackle

Tying Instructions

As always, start by crimping down the barb on your hook before placing it in the vise. Steve left his barb on here just to illustrate where the tie-in point is for the tail; at least, I’m pretty sure that’s what he was thinking.

So, start your thread behind the eye of the hook and then, with a few quick wraps, move it back to just above where the barb was. Then select a small clump of dark dun hackle feathers for your tail.

You’ll want a dozen or so fibers that are long enough so the tail will be just about as long as the shank of your hook. Now tie those in just above the barb, wrapping back to the edge of the bend and then forward to above the point of the hook.

Look at our first photo to see what your fly should look like at this point. Notice that Steve isn’t wasting any wraps of thread.

Thorax BWO

Next, take two small hackle tips from a neck or saddle hackle. Place them together so they form a V and tie them in a short distance behind the eye of the hook. The tips should be facing forward, toward the eye. Cut the excess off the back, then stand the tips straight up and make a few wraps of thread right at the base of the tips on the eye side.

Making the wraps of thread at the base of the tips should force them to stay up. Now, you will want to make a few figure eight wraps of thread around and between the two tips to separate them. Once you do that, move the thread to the back of the fly where you tied in the tail. The second photo shows what the fly should look like at this point.

Thorax BWO

The next step is to take a small amount of the Superfine Blue Wing Olive color dubbing and dub a tapered body. As always, keep it sparse. Finish your dubbing just behind the wings, creating a bit of a cigar shape – thicker in the middle than on either end of the taper.

Pick your dark dun saddle or neck hackle, sized appropriately to your hook – or with barbs about 1 ½ times the gap in your hook. Tie it in just behind the hackle tip wings.

The third photo shows what your fly should look like at this point.

Thorax BWO

Next, make two turns of the hackle behind the upright tips. Make two more turns in front of them, then tie off the hackle. Make a few more wraps with your thread just to form a small head on the fly, and whip finish. You’re almost done. Steve says that to really finish this fly, you want to lay the point of your scissors along the bottom of the hook shank at the front part of the fly and cut off the hackle that is sticking down below the body of the fly. By cutting these barbs away, the fly will float low in the water film, making for your “killer” blue wing olive.


It’s springtime. Tie one up, and get out there and enjoy it.

By John Haile. Tied by Steve Parrott. Photos by Tim Stechert