The Beaverkill is a true Catskill-classic with roots in the mid 1800’s, most likely it’s an adaptation of an earlier English pattern.
An in-depth discussion on the origins of the pattern can be found here.
Mustad 94840 (or other classically shaped dry fly hook)
Thin off-white to match body
White silk floss
Brown hackle barbs
Double-slip mallard-quill, divided
Step by step
1. Make a thread catch about 1/3 of the way from the eye of the hook, you do not want the wing to far forward as you will need some room for two turns of hackle in front of the wing. These flies were traditionally often tied with a small portion of bare hook shank behind the eye to accommodate a turtle knot and that’s how I tie mine, today this is mostly a matter of taste.
2. To create the double-slip quill mallard wing start by selecting a pair of well matched duck primary feathers, preferably from the same bird. You will need one primary from the left- and one from the right wing. Divide out the quill slips, you will need two from each primary feather, 3-4mm wide. Make sure they are all the same width. Lay the quill slips out on some foam (fly tying foam works very well), the two slips that will be facing towards you when tied in should be in their correct orientation, while the ones on the far side of the hook should be placed upside down.
3. Stack the wing on a needle, starting with the two slips that will be facing towards you. Make sure to align the slips as perfectly as possible on the needle. You better get this right as there is no way of correcting anything once the wing is tied in…
4. Tie in the wing with a pinch and loop, make sure its tied on straight. The wing should be a little longer than the hook, the distance from the hook eye to the middle of the hook bend is usually about right.
5. Raise the wing up by beading up hard with thread in front of the wing. Then make some figure of eights around the wings to secure them in position.
6. Tie in the tail, which should be stiff web-free hackle barbs, The length of the tail should be at least the length of the hook.
7. Tie in a piece of thin white thread by the tail, this will later be used to secure the body hackle to the hook. Tie in the white silk floss for the body.
8. The body finished and ready for the body hackle. I prefer to use thin silk floss and work once down, and once up the body.
9. Tie in the body hackle just behind the wing. I strip off the barbs on the hook-side of the hackle which makes for a somewhat neater fly. The body hackle should be about two sizes smaller than the main hackle, for a #12-hook use a #16 hackle. Make sure to leave room behind the wing to wind the main hackle.
10. Wind the body hackle, once you reach the tail grab the white thread you tied in in section 7 and wind this forwards to secure the body hackle to the hook.
11. Tie in the main hackle and wind this forward, three turns one in front of the other behind the wing, and two in front is usually about right. The length of the hackle should be at least 1.5 times the hook gape, I prefer a slightly longer hackle.