Popovics' Hollow Fleye design is based on tying bunches of bucktail (or other hair) on the hook shank in the opposite direction of the hook bend and propping it rearward at various angles with a thread wall. This method should not be confused with the reverse-tied bucktail flies conceived by Carrie Stevens and popularized by Keith Fulsher's Thunder Creek series. Both the Hollow Fleye and reverse-tied bucktails tie the bucktail in reverse on the hook shank. However, Thunder Creek flies have a band of thread behind the original bucktail tie-in point that binds down and restricts the hair to a single, more narrow shape. The Hollow Fleye has thread wraps only in front of the original tie-in point, which allows more control of the hair and the shape of the fly. Do not wrap back over the hair when creating the thread wall of a Hollow Fleye unless you want the hair to lie flat against the hook shank.

Hollow Fleyes work well with or without eyes. They can be tied on short-shank hooks with radically flared hair or on long-shank hooks with less-flared hair for a long, fusiform shape.

To create a tapered fly, you must surround the hook shank with at least three bunches of bucktail in progressively shorter lengths. A short-shank hook typically requires three bucktail bunches to fill the shank; therefore, each bunch of bucktail should be approximately two-thirds the length of the previous bunch. Long-shank hooks require at least five bucktail bunches, and the taper must move along at a slower pace to maintain a proper profile. I make each bunch about three-quarters the length of the previous bunch or longer when tying five bunches on a long-shank hook.

The angle of each bunch of hair controls the shape of a Hollow Fleye. The thread wall in front of the tie-in point allows you to manipulate the angle of the hair. The more wraps you make, the more the hair lies back along the shank for a slimmer profile. Fewer wraps allow the hair to flare more, creating a wide-body profile.

As a rule, the first bunch of bucktail should lie tighter to the shank than subsequent bunches to imitate the tail and slimmer profile of the rear of most baitfish. Each bunch should progressively flare outward more than the previous bunch. Keep in mind that the angle of the first bunch determines how the remaining bunches should stand. The last and shortest bunch of bucktail should stand at a 45-degree angle relative to the hook shank for a tall, full-profile baitfish.

The Hollow Fleye uses a thread wall to push reverse-tied bucktail toward the bend of the hook. Thunder Creek-style flies (bottom) have thread wraps over the bucktail that restrict the fibers to a more narrow profile.

Size and Shape
The size and shape of a Hollow Fleye is limited only by the length and consistency of the hair you use. Long, 7-inch bucktail with a #4/0 long-shank hook can produce 10-inch Hollow Fleyes. Other natural or synthetic fibers produce even longer flies. I have tied and fished Hollow Fleyes made from polar bear hair, ostrich herl, and Unique Hair with good results.

Popovics prefers bucktail over other materials because the naturally tapered tips impart a lifelike motion to the fly. Bucktail is available in most fly shops and is inexpensive.

Bucktail selection also affects the bulk of the fly. Bulky flies are best tied with crinkly hair. Use fine, straight bucktail for slimmer imitations. The combination of hair selection and angle determines the final profile of the fly.

The fly uses reverse-tied bucktail to flare the hair and create breadth and depth without bulk.

Fleye Desnsity
For dense, fully dressed flies, the butts of each new bucktail bunch should touch or come close to the previous bunch so the hook shank is not exposed. This requires more hair and creates a fly with a strong silhouette. For a sparse Hollow Fleye, use fewer bunches of hair spaced at less frequent intervals. You may use the open spaces between the hair bunches for other materials. Slide a bead or cone on the hook shank prior to tying and then sandwich it between two bunches of hair. Place the bead between the bunches closest to the hook eye to give the fly a seductive vertical action in the water, like a Clouser Minnow. You can also spin coarse, hollow bucktail from the base of the tail between the bucktail bunches to increase the fly's opacity and buoyancy for surface fishing and add an attractive wiggle when fished on a sinking line.

Combine the Hollow Fleye technique with other tying styles to imitate various food items with different shapes and sizes. You can make a delicious-looking Hollow Squid using the same monofilament extension as the Shady Lady Squid. Combine the Hollow method with the feather tails of flies such as Lefty's Deceiver, Semper Fleye (saddles tied in the round), or flat-wings to produce long, sleeker flies. I've done well with hollow-tied bucktail in place of ostrich herl in both Siliclones and Snake Flies. I've also used it to tie weedless, wide- profile Bendbacks. The Hollow Fleye method is an option for any pattern that normally uses a traditionally tied collar. One of the cosmetic benefits of this style is the tiny, almost nonexistent head.

Simple one-color Hollow Fleyes are effective, but this tying method allows you to easily add other colors. Replace the primary color with a different color or shade of bucktail in the last bunch to create a gorgeous two-tone effect reminiscent of classic swimming plugs. Alternating bands of color create a subtle blended effect. Add realism by using contrasting colors on the top and bottom to imitate the natural contrast of baitfish.