Wet fly fishing, long relegated to a back burner by trout anglers, is enjoying a resurgence. Only, now it's known as "nymph" fishing.

This is fueled in part by growing awareness that a large percentage of a trout's diet consists of immature aquatic insects and small crustaceans. These underwater organisms can be effectively imitated on fly hooks. In the present day flyfisher's lexicon, such creatures are all loosely classified as nymphs.

An attribute common to many underwater organisms is translucency. For centuries fly tiers have been experimenting with various materials, hoping to capture a similar semitransparent effect in artificials.

This is the reason under-furs from water animals such as muskrat, seal, otter and others are used in so many patterns. Because their fur is more water repellent than that of land animals, it tends to trap air bubbles, which theoretically at least, helps give this impression.

Tinsel is another material that, because of its reflective quality, gives a translucent, sometimes even transparent appearance. Tiers, whether they realize it or not, because tinsel reflects underwater surroundings, are obtaining the same "see-through" illusion with it that stage magicians project with mirrors. Many nymphs are virtually transparent between abdominal segnents. Tinsel ribbing imitates this very successfully,

About twenty years ago I became intrigued with the idea of trying to develop a fly that would simulate a fairy shrimp. These little creatures inhabit ponds, lakes and other still waters and are startingly translucent, in fact, so much so, that the pulsating vein that acts as their heart is visible and background colors show through them.

After experimenting with various materials and combinations to try to achieve something similar, one of the patterns I came up with was a modification of one that Sid Gordon described in a book published in 1955 and Jim Quick listed in "Fishing the Nympn" five years later.

Gordon called his pattern the "Swanson Wet-Dry Fly" and Quick named his "Susie's Pool Teaser Nymph". They were both tied with three or more feather sections overlaying a tinsel body in such a manner as to allow the tinsel to be glimpsed through them.

Gordon had discovered that caddis flies encase themselves in a bubble of air and then swim underwater to deposit their eggs. His pattern was meant to suggest their glistening appearance. Quick's "Pool Teaser" was merely listed in a dictionary of nymph patterns and no history or origin was given for it.

Although the modified pattern was inspired by a still water type, it proved to be successful in both streams and lakes. It is now a favorite with many very competent nymph fishers and is one of my own staples for Wisconsin waters.

Here is how it is tied: Secure a hook in a vise, (size 14 for streams and 12 for lakes are good bets) and coat the hook shank with fly head cement. Then starting at the eye end, secure tying thread to the hook by winding it over its own end for a few turns and spiral it back to a point just where the hook bend starts and half-hitch. This is usually just across the gap from the barb. Now saturate this winding with head cement.

You have just prepared the hook so that material you tie on later won't turn on the hook.

Cut two sections from a grouse tail feather, one about a quarter of an inch wide and the other an eighth of an inch wide. These are for overlay and underlay on the top and bottom of the silver body.

Secure the narrowest of these two sections by the tip to the bottom of the hook where the thread is presently half-hitched by a thread wrap and a half-hitch and do the same with the other section, only on top of the hook. Cement these half-hitches. The two feather sections should now extend out back of the hook for most of their length.

Advance the thread to a point approximately one third the length of the hook shank from the eye and half-hitch.

Secure a length of medium flat silver tinsel here by another half-hitch. Cement these half-hitches and wind the tinsel back in close spirals to the place just above the barb where the grouse sections are secured then forward again. Cut off the excess tinsel and cement this half-hitch.

Next, coat the tinsel body with fly head cement. What you are doing now is giving the tinsel a covering of lacquer to insure that it stays bright, just as a jeweler does to jewelry, and making sure it doesn't slide on the hook.

Pick out a brown hackle feather with fibers from one and one half to two times as long as the hook gap, secure and wind on as a shoulder hackle. Trim the hackle fibers off the top of the hook.

Fold the wide feather section ahead along the top of the hook and fasten it with a thread wrap and a half-hitch just back of the hook eye and ahead of the hackle.

Now bring the underlay forward in the same manner along the bottom, dividing the hackle, and fasten with a wind and half-hitch in the same place. Whip finish to form a head. Saturate the head with cement and cut the thread.

You now have a fly that will appear translucent in the water because the mirror-like sides reflect its surroundings. For instance if it's fished along a gravel bottom it takes on the general hue of gravel. If it's along watercress, it will have a greenish cast, near mud, it appears darker. The underlay and overlay saves it from being hard to see by giving it a profile.

Some tiers I know use other materials for the underlay and overlay. Duck quill sections are popular and more durable than grouse feather. Some use dyed duck quill and one man substitutes small clumps of squirrel tail which has a mottled appearance similar to grouse feather.

Overlays can be made more durable by putting a drop of fast drying epoxy cement where the feather folds forward over the tinsel's edge.

Nymph fishing can be very productive, but it is also probably one of the most challenging methods. Many a flyrodder who earned a trout fishing reputation using dry flies, has developed a healthy respect for the old-time wet fly fisher after gaining a little experience with nymphs.

Fish them with fine leader tippits (4X for size 12 or 14 flies is about right) and a rod with guides large enough and close enough together to make line shooting easy.

Remember all the time a nymph is in the water, it is working for you. There are so many different underwater creature with such a variety of habits that it's pretty hard to fish something in a way that doesn't suggest one of them. However, it won't catch fish going whoosh, whoosh, back and forth in the air.

Extending line by false casting when fishing nymphs is silly. Not only does it waste time, but it dries the fly and leader so they don't sink quickly. Once the nymph is thoroughly soaked, it must be kept that way so it sinks immediately on each cast.

When small stream fishing for trout, stay out of the creek as much as you can. Dress as inconspicuously as possible. Wear clothes that will blend in with stream surroundings. Stay back from the bank edge and move slowly and quietly. Fish from a crouch or kneeling position and step softly.

Cast upstream, or across, or down, anyway you have to get the nymph where you want it. Place it upstream from where you think a fish will be and let the current sink it as it takes it to the fish. When you think it may be near a fish, lift the rod tip and start it towards the surface. This is the most natural movement you can give a nymph. Do this several times on a drift.

Pay special attention as the nymph swings and lifts at the end of a drift. Then retrieve slowly back close to you before picking up.

Often a little lead wire tied in a knot around the tippit knot will heip get your nymph down when fish are deep.

The hardest part of nymph fishing is learning to recognize takes. For most Wisconsin stream fishing, a floating line is best. It must be a color that you can see under all light conditions. Watch the line constantly and at the very slightest variation in its drift or when retrieving, set the hook. The average novice will have dozens of takes that won't be recognized,

Fish the silver nymph at the heads and tails of pools, the outside of bends and along undercut banks. Retrieve it slowly along watercress, snags and places where the current divides. In hot weather concentrate on areas like riffles, eddies, and turbulent water at the head of pools. As the temperature rises trout need more oxygen and seek out aerated water.

In lakes, fish the edge of weed beds or other cover. Concentrate on the shady side of logs, stumps and shore line growth. Mornings and evenings often find fish feeding in shallows and flyrod lures are ideal then. They can be presented without alarming splashes.