I’ve posted several thread-bodied nymph patterns, but thought it might be interesting to approach this topic more generally, with some “generic” recipes rather than specific patterns.
The major advantage of a thread body – besides ease of tying – is the ability to create a fly of very low bulk with non-buoyant materials, to assist in getting to the bottom quickly, and staying down in turbulent bottom currents. Factors to ensure this sinkability (in addition to technique – a good tuck cast, good leading skills; and leader/tippet selection) include weight (bead head and/or underbody weight), lack of buoyant materials, and slimness / lack of bulk which might slow the rate of descent and offer the currents more to play with.
Dubbed bodies may offer intriguing colors and movement, but do this at the expense of added bulk and perhaps buoyancy from trapped air; this can be overcome with other tying factors and with technique in use, but it’s nice to have some flies that will more naturally plumb the depths of turbulent water. Pheasant tail falls somewhere in between, adding little bulk, and variants on my bead-head pheasant tail nymph remain among my go-to patterns.
The use of a plain thread abdomen sacrifices movement for sinkability, so this needs to be made up for – with virtual movement, using color and flash in a tag- or collar- hotspot, in ribbing, and perhaps in movement and/or flash in the thorax.
Hook – as the emphasis is in hugging the bottom, a jig-style hook is an advantage. See my reviews of these. Size 14-18.
Weight – keeping these patterns slim, I avoid underbody weight, and rely on a tungsten bead sized to the hook; slotted, for a jig-style hook. See my discussion of bead sizes in previous posts.
Tail – to be consistent with the slimness mandate, i like a sparse tail of 3 fibers of coq-de-leon, and stock a range of colors in pardo. There are a number of potential sources, but I love the range available from Troutline. Romania seems like quite a distance from the Pacific Northwest, but their quality, prices, service, shipping and delivery times are excellent. The Whiting Tailing packs from the Feather Emporium are also very nice.
Tag – I’m usually tying these in somewhat neutral “suggestive” colors, so a colorful hot-spot at tag & occasionally at collar is a nice touch. Tying thread may suffice, Veevus makes a luscious orange and a deep red. I’ll occasionally spice this up with a bright color of Devaux body thread, Datum Glo-brite floss or the more translucent Hends body quill, there are a number of materials that might work well for this small but significant feature.
Ribbing – I’ll most often include 2 ribs, wound simultaneously, a heavy rib to emphasize segmentation and a lighter following rib for flash and virtual movement. Sulky tinsels make a good segmenting rib in black or brown, (or in a brighter color over a dark body), and Fly DK pearl quill body material is very nice in graphite, pearl or other colors.
For a finer following rib, I’ll most often use a fine metallic o.1mm wire in color to suit the pattern.
Abdomen – this will be the main tying thread, usually in a “suggestive of natural” color. I’m very fond of the Veevus threads, re color choices, tying properties and durability. #10-12 work fine. The Georgio Benecchi threads are also very nice, and there are likely as many choices and preferences here as there are tiers.If you choose to use a split-thread-dubbed thorax, choose a thread you’re comfortable splitting, or adapt with a dubbing loop method.
Eric Stroup reminds me that most anything in olive found in the stream is edible, so this is a common choice. I’ll often use
olives (Veevus, Georgio Benecchi; and Uni makes a nice range of olives, including their “watery olive,” a very nice color)
tobacco (Georgio Benecchi)
black (esp. for late fall/winter stonefly patterns)
dark purple, dark blue (nothing in the stream looks like this to me, but the trouts seem to see things differently)
yellow (Veevus; we have a lot of little yellow “Sally” stoneflies in our high-gradient mountain streams)
I’ll create a small conical “dam” behind the bead to anchor this in place, but otherwise ignore the common advise to “create a tapered body,” preferring instead to keep this slim & minimalist. Even then the fly, once ribbing is added, will most likely end up fatter than most natural food in the stream. When feeling obsessive, I’ll spin the thread counter-clockwise to flatten it for a smoother abdomen and better coverage. Not sure the troutses really care. The tie-off of the ribbing material will be buried under the thorax.
Wingcase – I rarely bother. If you feel it needs one, remember this is a jig-style pattern, so this goes “under” the hook if you do add one.
Thorax – Lots of choices here. Either maintain the low-bulk theme and make this sparse with a thin dubbing rope of a sparkly material (John Rohmer’s Arizona Synthetic dubbing, Jan Siman Peacock Dubbing, &c.; or trade off some of the bulk you’ve saved in the abdomen, and “spend” a bit of bulk in exchange for movement with a split-thread dubbed thorax of one of these, of one of the Jack Mickievycz blends, or your dubbing-of-choice, or squirrel body hair (a favorite of mine, hard to beat), or CDC.
Collar hot-spot – I’ll occasionally swap out the tying thread at this point to finish off with a bright thread, creating a collar hot-spot behind the bead, usually matching the tag hot-spot. I’ve been told to avoid combining tag- and collar- hotspots on a fly, with the suggestion that this might confuse the fish, but I’ve never seen one pondering whether the fly might be coming or going. Not sure this is ever necessary either. My pheasant tail pattern has tag- & collar hotspots as I use a bright tying thread throughout, showing only in these two locations, so not so much by intent as by default. On a thread-body pattern this adds some work, so I only do this if the fly could really use the color (esp. black patterns).
This “recipe” permits a great variety of options & alternatives; the downside of this is that one can end up with a great variety of flies in one’s box, especially if feeling creative or bored at the bench.
I know there are folks who go out to the water with upwards of 1,000 flies, of a great variety of pattern. My problem with this would be “choice paralysis” – feeling immobilized with too many choices while standing dumbly waist-deep in the stream, with no idea which fly to tie on. Were I to carry 1,000 flies in my nymph box, I’d prefer a range of sizes and weights of perhaps 4-6 patterns, selected for the season; lots of olives for spring & summer, with more blacks purples & blues for fall & winter. With plenty to replace flies lost to the bottom in good runs (as you will if fishing well and avoiding wading in to a good lie to retrieve snags), and to the shoreline alders & the cedar limb that always seems to lie over the best pools, and to offer to those guys who ask “what they’re taking” or mutter about me “catching all those go&*d@#^ed fish.” Since at least half of these will be orange- and olive-tagged bead-head pheasant tail nymphs and peeping caddises with green, cream or pumpkin “peeps”, with a few hare’s ears, that leaves room for 2-3 thread-bodied patterns. Perhaps with a few new novel “creations” tossed in to see if these might rise to the level of future favorites.
I’ll usually fish these singly, to give them the best opportunity to tap along the bottom in unencumbered drift; or occasionally as the point fly, with a small soft-hackle wet off a dropper above, in that case intending the dropper as an emerging nymph & the point fly as “sacrificial” so it might nearly as well be shot; I merely feel cleaner this way. Two-nymph rigs are often subject to drag when the flies are caught in conflicting micro currents, esp. in pocket water; and I’ve lost enough good fish on “two-fers” when an 8-incher grabs the free dangling fly while I’ve got a nice fish already on the other. First time, shame on them; second time, shame on me.