The Bivisible is a pattern that dates back to the 1920’s and, if not directly invented by Edward Ringwood Hewitt, it was certainly popularized by him in his 1926 book “Telling On The Trout”. In the book, Hewitt states darker colors are more visible to trout looking up, than light colors, so most of the fly is constructed of palmered brown hackle. From above, however, the brown is difficult for anglers to see, particularly in low light. Thus, a few turns, or as Hewitt puts it “a small wisp” of white hackle, is added at the head of the fly which makes the pattern more visible. Some tiers will add a brown hackle fiber tail but I generally prefer it without.
Other than the hook and thread, only two other ingredients are needed: brown hackle and white hackle. Today’s high quality hackles make the tying process much easier. How anyone tied a decent looking bivisible with indian neck hackle is beyond me. Nowadays necks have long, consistent, nearly web-free feathers down to the smallest of sizes. Here you can see the stem begins to thin just about where the webbing ends and most every bit of the feather is usable from there, all the way up to the tip. With the barbules pulled down, you can really see how straight and uniform everything is. All hackle feathers have a shiny side, which faces out on the neck or cape, and a dull or backside, which obviously faces inward. It’s this back or dull side that’s concave or cupped. When you wrap a hackle around a hook shank, you’re generally compressing most of the barbules on the side of the stem that contacts the hook, while the barbules on the other side of the stem extend out perpendicular to the hook shank. Nearly all of the shank-side fibers that are compressed will fold around the stem and stick out perpendicular as well. These then contribute to the fullness of the hackle collar. For this to happen consistently, it’s extremely important that the thread base, over which you’re wrapping, be as smooth as possible. Any large lump or bump can cause hackle fibers to go shooting off in all directions. Keeping the hackle wraps very close together really helps these extra fibers to stay pointed up and out as opposed to forward or back on the hook shank. Although there are different schools of thought, I find wrapping hackles so the shiny side of the feather faces forward, invariably results in fewer trapped fibers at the head of the fly where they can block the hook eye.
Alright, enough about hackles, let’s get on to the fly. For the bivisible I like a slightly longer dry fly hook like the Dai-Riki #300, here I’m using a size 16. You can use shorter-shanked hooks like the Dai-Riki #305 on the left, but I think the proportions look better with the #300 on the right.
For thread, I’ve loaded a bobbin with a spool of black 6/0 Danville Flymaster. Leaving some space behind the eye, take wraps rearward before snipping or breaking off the tag. Continue taking wraps rearward until your thread is about halfway between the hook point and the barb.
We’re going to start by selecting and preparing the brown hackle. The most prime hackles are found near the center of the neck as opposed to out at the edges. It’s a good idea to measure hackles before you pull them from the neck, to make absolutely sure the barbules are the correct size for the hook you’re using. Here you can see all the barbs fall within the size 16 range. You may notice some look a bit shorter than others. These are the ones that have rotated around from the shank side of the stem. Once you’re satisfied with the size and quality of the feather, pluck it free from the neck right down by the skin. On a high quality hackle, you’ll notice the webby stuff extends only a short distance from the butt end of the feather. Snip the butt end off where the web ends and the stem begins to thin. To ensure a uniform base on which to wrap the hackle, I like to strip off enough barbules to expose a little more than a hook shank length of stem.
Tie the feather in on the near side of the hook with it’s shiny side facing toward you. Leave just a small amount of bare stem exposed behind the initial thread wrap, then continue taking uniform wraps up the hook shank to create a nice, smooth and even underbody. Leave your thread about 2 eye lengths behind the eye. Get hold of the hackle feather and begin wrapping it around the hook shank. You can see here I’m trying to make sure the shiny side of the feather faces forward. It’s always the first wrap or two that are most difficult. Once you get going, the rest should just fall into place. When you reach your tying thread, pull the hackle to vertical and take three wraps of tying thread to secure it. When you’re done, reach in with fine point tying scissors and snip the tip off.
Repeat the measurement procedure with the white hackle. You want it to be as close in size to the brown as possible. To prepare the hackle for tie-in, strip a scant 1/8” of fibers free from the stem. With the shiny side of the feather facing you, lay the stem against the hook shank so it extends just to the return of the hook eye. Give your thread a counter-clockwise spin so it will jump rearward when you take a wrap. Continue taking thread wraps to bind the stem to the hook, doing your best to create a smooth foundation in the process. Begin winding the white hackle so it starts right where the brown ends I inadvertently left a small bump here which, as you can see, wants to jostle the hackle as it’s being wrapped. Once again, a smooth foundation is absolutely key to a quality hackle job. Leaving just a teeny amount of space behind the eye, take 3 tight thread wraps to secure the hackle then reach in with your tying scissors and snip the tip off as close as possible. Do a 4 or 5 turn whip finish to cover the butt end and create a small, neat head on the fly. You can then snip or cut your tying thread free.
A drop of head cement applied to the wraps will ensure the hackle won’t pull free and unwind. If wrapped correctly, you shouldn’t get too many errant or trapped fibers. The bivisible is a time-tested attractor pattern that floats well and represents a wide range of aquatic insect species.