Hot Legs

by Oliver Edwards 

Discover 6 ways to add durable legs to your nymph imitations.

It has become almost mandatory to add legs to nymphs, pupae, and some larvae imitations, but are these appendages necessary in every instance? The answer is that it depends what the real insects are doing when you are fishing.


For instance, is your fly intended to represent a real nymph or pupa that is actively swimming toward the surface in advance of emerging? Or, is it meant to copy an insect that is dead drifting, or a poor creature that is exhausted after failing to emerge? You must always consider the lifestyles of the insects you are trying to mimic, but in this article I’m referring to tying imitations of nymphs and pupae that swim with efficiency and purpose.

I’m sure that most readers of this magazine are familiar with the habits of real nymphs and pupae. I must not, however, assume that everyone has the same level of knowledge. So, to make sure that we’re all on the same page before examining how to tie better flies, let’s first review a few basics about the habits of real nymphs and pupae.

What We Need to Know
As emergence time draws near, some nymphs gradually migrate toward the water’s edge and then simply crawl out on shore to develop into full-fledged adults. Stoneflies are typical of this group; you’ll often find their cast-off nymph shucks many feet from the streambank, sometimes even clinging spookily to vertical surfaces such as tree trunks and cabin walls. Some mayfly nymphs, as well as the pupae of several species of caddisflies, also crawl out to emerge, but usually only a few inches to a couple of feet from the water’s edge; none travel as far inland as stonefly nymphs.

The insects that crawl out of the water must avoid the watchful eyes of trout, and they use the nooks and crannies of the stony substrate to great advantage; some even make their move under the cover of darkness. During a big hatch, especially in high, swift water, there may be casualties. Some of the nymphs become dislodged and are part of what is known as the catastrophic drift. Now the watchful fish are presented with an opportunistic meal. This may sound implausible when considering such sure-footed creatures as stonefly nymphs, but it does happen.

Small Nynph

Small Nymph
Hook: 2X-long nymph hook, sizes 18 to 12.
Thread: Danville’s 17/0 Spiderweb for hook sizes 18 and 16, tinted with an olive permanent marker; Moser Powersilk for sizes 14 and 12. You may substitute with your favorite brand of ultra-fine tying thread.
Weight: A narrow strip of adhesive-backed lead foil.
Tails: Stout, tapered guard hairs dyed olive. European badger is best, but you may substitute with groundhog or nutria.
Abdomen: Olive Flexibody or Thin Skin, color to match the natural insect.
Thorax: Fine natural or synthetic dubbing, slightly darker than the abdomen.
Wing bugs/thorax cover: A section clipped from a black quill feather such as crow or turkey.
Legs: A small, soft, webbed white hen hackle, dyed olive, or a hackle from the upper back of a partridge, dyed olive.
Head: Tying thread, wrapped neat and conical.
Note: You must include an undercover for the thorax in the fifth legging method. (See the accompanying drawings.) Select a section of quill in a color to match the thorax dubbing.

Sawyer's Nymph

Sawyer’s Nymph
Hook: 2X-long nymph hook, sizes 18 to 12.
Weight: Very fine copper wire colored red, such as small, red Wapsi Ultra-Wire. This wire also serves as the thread.
Tails: The tips of four brown fibers from the center tail feather of a cock pheasant.
Body: The remainder of the fibers used to tie the tail, wrapped up the hook shank.
Wing buds: Four reddish fibers from a cock pheasant tail feather. The dark bar on the fibers should be pronounced.
Note: Yes, Frank Sawyer actually used the wire as the thread. This is an unusual but very simple and effective technique for tying a small impressionistic nymph.

Caddis Pupa

Caddis Pupa
Hook: Regular wet-fly hook, sizes 18 to 10.
Thread: Danville’s 17/0 Spiderweb for hook sizes 18 and 16, tinted olive permanent marker; Moser Powersilk for sizes 14 to 10. You may substitute with your favorite brand of ultra-fine tying thread.
Weight: A narrow strip of adhesive-backed lead foil.
Abdomen: Flexibody or Thin Skin, color to match the natural insect.
Thorax: Hare’s-ear, rabbit, or squirrel dubbing, or a blend, color to match the natural insect.
Wing buds: Any brand of very dark polypropylene sheet material used for making pre-cut wings. Coat the material with Flexament or a similar cement before cutting the wing buds to shape.
Trailing legs (optional): The tips of three or four pheasant tail fibers.
Rowing legs: Rubber legs.
Antennae (optional): Two dark guard hairs.
Head: Two or three pheasant tail fibers, cemented, twisted together, and wrapped on the hook to form a small head.
Note: This is a prototypical pattern, so specific body colors are omitted. All species do have dark wing buds during emergence. Remember to tie this pattern on a straight-shank hook; swimming caddis pupae do not have curved bodies.

Stonefly Nymph

Stonefly Nymph
Hook: 2X- or 3X-long nymph hook, sizes 14 to 2.
Thread: Moser Powersilk, or regular 8/0 (70 denier) or 6/0 (140 denier) thread, color to match the underside of the nymph.
Weight: Lead wire on larger sizes; adhesive-backed lead foil on smaller sizes.
Tails: Biots (split lengthwise), hackle stems, or stout guard hairs.
Body: Natural or synthetic dubbing, color to match the underside of the real insect. You can use rather coarse dubbing on larger flies.
Rib: D-Rib for larger patterns; nylon monofilament on smaller flies. Select a material to match the size of fly you are tying.
Legs: Rubber legs, Sili Legs, or a similar product. Select a thickness to match the size of fly you are tying.
Wing buds and pronotum: Sections clipped from a wing or tail quill feather such as speckled brown turkey.
Antennae: Biots (split lengthwise), hackle stems, or stout guard hairs.
Head: Well lacquered on both sides.
Note: This is a prototype pattern, so the author has given little information regarding color. Tie this fly in colors to match the nymphs in your local waters. The author shades the top of the abdomen with a permanent marker, but warns us to be careful to prevent the ink from bleeding to the belly of the abdomen.

Wisdom suggests that when large stonefly nymphs are dislodged and begin drifting, they adopt the fetal position with their legs dangling backwards; outstretched or dangling, these are seriously large appendages that I believe should be included in your patterns. That being said, however, there are some very well-known large stonefly nymph imitations that are completely legless yet sport stout, overemphasized biot tails and antennae. I haven’t figured out this logic; if chunky appendages such as stonefly nymph legs are considered unimportant, why include the less visible appendages?

Some patterns also benefit when the legs are exaggerated just a little. I’m referring here to length rather than the number of legs. Using a fly containing too many legs gives the game away and the trout spot the forgery. It also makes sense to imitate legs using some soft, flexible material. Soft-hackle fibers have been a favorite choice since the beginning of fly tying. Heavily lacquered, anatomically correct legs may look good in the vise, but they invariably fail to impress the fish. Today, many tiers prefer using flexible rubber legs.

A great many nymphs swim to the surface to emerge, such as the classic darting types of the mayflies such as Baetids, Isonychids, and tiny Centroptilum nymphs. These families of streamlined insects appear to have no legs when swimming; extended legs would only interfere with their speedy maneuvering. These nymphs simply tuck their legs against the underside of their thoraxes. Frank Sawyer knew this 50-odd years ago, and he purposely designed his famous Pheasant Tail and Grey Goose nymphs without legs. Sawyer used these flies for his very effective fishing technique called the “induced take,” in which he mimicked a swimming nymph rising to the surface. The message is obvious: If you’re tying an imitation of a swimming nymph, and it is intended to copy the real thing when it is in swimming mode, omit the legs.

A Myth Debunked
Emerging insects face many problems; they don’t all make it to the surface and some die in the effort. Some of the smaller and tiny nymphs seem particularly vulnerable. Their enemy, though, is not the surface meniscus as some would have us believe. This is a misconception that my longtime fishing mate and entomologist Stuart Crofts has debunked. Stuart rears nymphs for research, and his work exposed the myth.

According to Stuart, the meniscus is actually a nymph’s ally during emergence. As a nymph reaches the surface, the insect appears to be attracted to the underside of the meniscus where it is held and stabilized. Then, as the nymphal cuticle opens along the top of the thorax, the meniscus actually bends down and seems to grip the edges of this split to reveal the escape hatch; the meniscus almost pulls it open. The meniscus acts much like a tiny elliptical doughnut, holding back the water and giving the emerging insect a clear air passage to the surface. Stuart has observed this phenomenon many times.

A large proportion of nymphs fail to clear this hurdle during emergence, and some species appear more prone to failure than others; perhaps they expire from the stress or exhaustion of simply swimming to the surface. The point is that as soon as they stop swimming and position themselves for emergence, their legs become outstretched. Then, when emergence begins, the legs are held straight back so there is less hindrance as the adult crawls out of its nymphal skin.

Some nymphs may make more than one attempt at emerging. Each time they arrive at the underside of the surface, the legs come out in repose. But these insects rarely make it; the stress takes its toll and they die with their legs outstretched.

This drama is played out on an endless conveyor, on countless days, on countless rivers, streams, and creeks. A massive hatch may result in thousands of expired nymphs, all bowling along somewhere in the water column, all with their legs outstretched, and each one an easy morsel for a trout. These nymphs are not effectively copied by a Sawyer-style pattern. In fact, on my local freestone streams here in Yorkshire, England, knowledgeable anglers rarely use Sawyer’s nymphs. We never see the fish, even when wearing polarized sunglasses; the streambeds are a mosaic jumble of dark colors—vague patches of brown, tan, and green—seen through a surface that is usually broken and roiled. We never “swim” our nymphs; we cannot “induce” the trout to strike, because we cannot see our targets. We fish using the classic upstream or quartering presentation and allow our flies to dead-drift. Our most successful patterns have outstretched legs. In this situation, fishing a well proportioned artificial of the correct size, with just a few nicely radiating legs, is usually lethal—but a hatch does help, of course!

Not all mayfly nymphs are adept swimmers, including some that make up the largest hatches. The Ephemerellids (Hendricksons, pale morning duns, and sulfur duns) are poor swimmers. These nymphs are classified as crawlers, or spiny crawlers, and swim with an inefficient dog-paddling, up-and-down rocking motion. The flat-headed nymphs of Heptageniidae (quill Gordons, Cahills, and foxes) are also not designed for swimming. In fact, several species in this important family have no need to swim or even crawl out because they transpose underwater; those that do emerge and transpose at the surface use a dog-paddle motion and some ineffective tail lashing to swim to the surface. There is plenty of leg action in the swimming motion of both these groups, and my imitations feature adequate legs.

There is another instance when nymphs appear in the water column in the repose or semi-repose attitude with legs outstretched: this is when they voluntarily let go of the streambed and simply allow themselves to be carried off downstream in the water column.  This phenomenon, called invertebrate drift, is well known. The distance they travel varies considerably within the various insect groups. The peaks of drift activity are dawn and dusk, which you can quite easily check yourself by using a fixed insect seine. It is no coincidence that the last two hours of the day, just before dusk, often produce the best sport; quite simply, there is more underwater activity going on.

Don’t Forget the Caddisflies
Emerging caddis pupae should also be on the “hot list” for the subsurface fly fisher. Emerging caddis pupae (technically, they are called pharate adults once they have escaped from their pupal cocoons) are now fully formed adults entirely encased in the thin, flimsy, semi-transparent pale tan skin we fly fishers call the “shuck.” Everything is encased, even each individual leg and antennae. Pharate adults are very interesting, particularly their legs. These insects fall into two categories: swimmers and crawlers. From many years of fishing during very good caddisfly hatches, I have found that the swimmers produce the most reliable and pulse-racing sport. The reason is simple: Swimming caddisflies are more dynamic and just asking to be chased and grabbed. They usually appear in good and sometimes massive numbers, and excite the hell out of the trout on both sides of the “pond.”

When reading the book Caddis Super Hatches, by Carl Richards and Bob Braendle (Frank Amato Publishers), you quickly realize that two families of caddisflies dominate the United States: Hydropsychidae and Brachycentridae, or in fly fishing terms, the spotted sedge (also known as cinnamon sedge or little sister sedge) and the Grannom (little black caddis or Mother’s Day caddis). Both of these families also have “super hatch” status here in the United Kingdom.

Members of both these families have swimming pharate adults, and the middle pair of legs propel the insects to the surface. These legs are positioned almost perpendicular to the body when swimming, and they have a dense fringe of minute hairs extending along the tibia and tarsus sections. This “swimming fringe” effectively widens both legs, making them very efficient paddles. The rapidly beating legs are a very dynamic trigger, encouraging the fish to strike.

There is another quite important trigger on caddis pharate adults, and although not the subject of this article, it deserves to be mentioned. The wing pads are a very striking feature: distinctly angled or almost drooping, often detached at the tips, bulging sideways somewhat, and very dark or almost black. I contend that they are an important trigger, and I always incorporate them in my patterns.

I guess that it is no longer fashionable in the United States to bother adding much detail on caddis pharate adults—“pupae,” if you prefer. Glistening silver sheaths of Tri-lobal yarn mimicking trapped gas bubbles have, it seems, displaced detail, and besides, who the hell wants to mess with detail? Let’s just go fishing! Well, call me an old disbeliever or a fly-fishing heretic, but I remain unconvinced. I’ve been down the “bubble-trapping Antron sheath” road, and I quickly went back to my own pattern with its two distinct outstretched rubber legs and dark drooping wing pads.

Try the accompanying methods for adding legs to your nymphs: they’re easy and fun to make, and I’m sure your patterns will benefit. I’m sorry that I have no drawings to show how to tie my complete caddis pharate adult, but I simply replace the common knotted pheasant-tail legs with a pair of rubber legs. Oh, one more thing: emerging caddis pupae, both crawlers and swimmers (the pharate adults), are all the same anatomically. Okay, I know there are differences, but not from a fly-tying point of view. All you need is one prototype pattern tied in colors and sizes to match the real caddisflies in your local waters, and remember to make your swimmers on straight-shank hooks; the real ones don’t swim with curved bodies.

Now get going. You’ve got lots of flies to tie.

Oliver Edwards is one of the world’s leading proponents of tying “fishing” realistics. He is a gem of a fly designer, and we are always excited to receive one of his articles; it is with particular pride that we have been bringing you Oliver’s articles and artwork.

Oliver lives in England but often visits the United States to attend fly-fishing shows and appear at clubs. If you’d like to learn more about Oliver’s flies and fishing techniques, be sure to check out his excellent Essential Skills series of instructional DVDs; we can’t recommend these highly enough.

Tag it:
Furl it!