Czech Nymph
Thread: Pale.
Hook: Size 12 or larger, curved hook.
Underbody: Lead wire.
Outer rib: Fine monofilament nylon.
Shellback: Flexibody or Body Stretch or similar (colour with permanent pen).
Inner rib: Flashy strand or fine gold holographic tinsel.
Body: Medium texture dubbing.
Head: Colour with permanent pen and varnish.

Czech Nymphs expect to spend their working lives near the bottom of the water column. To my mind, that means they should be simple, robust flies, designed to survive being battered against rocks and designed to be tied quickly so losing a fly is not a reason for tears.

If Czech Nymphs imitate a specific insect, and I like to think they often do, then it’s a form of caddis larva. When we tie them with hot-spots, or make the whole fly one shocking pink hotspot, it’s slightly harder to believe Czech Nymphs are imitative – then it’s more about how and where fish meet them that imitates or suggests something a grayling or trout really should eat.
Czech Nymphs tend to work in teams of three, one heavier fly on a dropper and two slimmer flies on the point and other dropper. This is one of the slim chaps. All Czech Nymphs are tied on (large) curved hooks; size and curve have become accepted parts of the pattern.

When Czech Nymphs arrived on the competitive fishing scene, hooks posed a problem. Anglers from mainland Europe used hooks from their local manufacturers (Knapek and Admiral were the two makes most often mentioned) and their hooks were larger and often stronger than those available in the UK. We had a good selection of hook-makers but few, if any, made curved hooks quite big enough for really meaty Czech Nymphs and only the largest sizes were suitable for slimmer lighter patterns.

Knapek hooks are now available in the UK. My sample fly is tied on a size 10 Partridge Flash Point Fine Wire Czech Nymph – excellent hooks. I could as easily have tied on just about any make of curved hook but only the larger sizes – size 12 or larger. For League flies the make of hook is not important. Use any curved hook, size 12 or larger.

All Czech Nymphs have weighted under-bodies. For simplicity, I’ve used one layer of fine, lead wire to form a slim under-body. I could use a strip of self-adhesive lead tape. For fatter, heavier flies I’d use more than one layer and create a tapered lead under-body or a layer of square lead or invest in hooks preloaded with a lead under-body. (Real depth-charges mean several tungsten beads or many layers of lead with an outer coat of tying thread and varnish.)

The shellback is usually plastic, either thin rubbery strips or stiffer strips cut from vinyl sheets. The shellback should pull snug over the top half of the body and no more. I want the rib to pinch into the back and dubbing layer to form segments. If the strip is loose it slides down the side of the hook as I cinch the rib down, too wide and the back wraps under and around the whole body of the fly.

Flexibody (Virtual Nymph), Magic Foil (Siman) and Body Stretch (Veniard) all work well. I’ve used Flexibody simply because that’s what I have. Thin Skin (Wapsi) is an obvious alternative to Flexibody, looks great, but rather frustratingly and frequently when pulled taut over the back the first tight thread-wrap at the head slices through the strip.

Czech Nymphs come in a host of colour combinations; this version has a simple two colour body with a slightly darker back. I’ve used Sow Scud Dubbing, opossum blended with Antron; gives a light attractive body and stays light when wet. I could, and often do, use pure, natural dubbings, eg hare, possum, squirrel etc., or one of a host of excellent medium texture synthetic dubbings. (League flies can be tied from any dubbing with a suitable texture and any colour.)

The segmented body is formed by pulling the rib tight, cinching into the body and back, so the rib should be strong. Wire breaks, oval tinsels break and fray, simple monofilament nylon is cheap and strong – it works well but slippery nylon does need to be tied in very securely. The flashy rib under the shellback is not part of all Czech Nymphs but I like the hint of something gleaming under the back material.

Thread is a personal choice. I tend to tie Czech Nymphs using fine white GSP thread and colour the head with permanent pens. I like the security of very strong thread and light coloured thread can’t dull down wet dubbing. Otherwise (when I’ve run out of GSP), I choose a light-coloured conventional thread, Danvilles 6/0 Flymaster or UTC 70. (Both 6/0 Flymaster and UTC 70 are 70 Denier nylon threads.)

Tip 1
Tying on curved hooks is fraught with danger. Thread can slip off a curved shank only too easily so it pays if you make a quick whip-finish or hitch whenever the thread is parked. I change the angle of the hook often when I tie on curved hooks – either by repositioning the hook in the vice or by tilting the head – whenever possible the thread is hitched in place before I move a hook.

Tip 2
Superglue or CA Glue or Krazy Glue or Cyanoacrylate is great stuff. But! Use it sparingly! Be cautious about tying over wet glue as it soaks into thread and dubbing making it impossible to go back. Also, it sets to a dull, lifeless matt finish. Newer, thicker gel glues can be used more precisely and have far less tendency to wick or run to places we don’t really want them to go.