Biots for Body Material

Biots are actually highly specialized barbs that form a vane on the leading edge of a bird's flight feathers. Biots taper rather abruptly and the butt end is relatively wide, which makes tying off a biot cumbersome. However, biots make handsome bodies and can give two distinct kinds of segmentation depending on how they are wrapped. The natural, undyed biot is quite flexible and strong, and can usually be tied without soaking it. Commercially dyed biot strips, however, are often brittle and prone to splitting when tied. Soaking them before use or storing them in water for short periods of time can improve the handling characteristics.

Individual biots are asymmetrical. One side of the biot contains a tiny row of fringelike barbules. A wrapped biot can produce either a smooth body or one with a fringed rib, depending upon which direction this edge faces during mounting.

Turkey biots are probably the most popular because they are the longest, most easily handled, and well-suited to larger hooks. Shorter biots, such as those from goose or even duck feathers, are better proportioned to smaller flies, though they are more difficult to wrap. These biots are generally narrower than turkey biots, producing a closer segmentation for smaller bodies and are less bulky when the body is tied off.

There are two basic ways to determine the mounting orientation of the biot. Peel an individual biot from the end of a strip of material. You will notice an indentation or notch at the base of the biot. This notch may be shallow or deep, depending on the material. The direction that this notch is positioned during mounting determines whether the body will be smooth or fringed. If the biot is clipped from the strip with scissors and the notch cannot be seen you will notice that it is slightly curved or cupped from side to side. On some biots this cross-sectional curvature is quite pronounced; on others, it is less conspicuous. The convex side of the biot tends to be glossier or shinier and darker or more distinctly marked than the concave side. This curvature can be used as a guide for mounting orientation.

Biot bodies can be reinforced using head cement or CA glue. If head cement is used over the wrapped quill, it should be thinned with solvent until it is quite runny; if CA glue is used, it should be the liquid type. Note thinner cement penetrates more readily, avoiding any buildup that might obscure the body segmentation.

The simplest approach is to apply a drop of adhesive over the wrapped body as the very last step in tying the fly. However, coating a wrapped body with cement results in a glossy finish that may or may not be desirable. As such, you can apply a thin film of head cement or CA glue to the thread foundation. Immediately wrap the quills to the tieoff point, using just enough tension to seat the quills against the wet cement, but not so much pressure that adhesive is squeezed out between the body wraps.