Wing Cases, Shell Backs & Wings to invert or not to invert?
I’ve had several questions and a few conversations lately about wing cases on jig nymphs and other flies tied to be inverted. Many other tyers will invert their wing cases (tie them on the bottom or belly of the hook) on inverted flies in the assumption that the wing case would not be visible to a trout if it was placed on the top of the hook once it flips upside down. As you may have seen on my flies such as the Penny Perdigon, Quill Perdigon and Stone Fly Patterns, I do not invert wing cases on nymphs tied so that fly rides upside down. In answer to the questions I've had on this, here are some reasons why:
Stone Patterm - Credit Grant Hilder (Reel Fly Fishing)
Invertebrates do not necessarily swim or drift upright in the water column. this has been witnessed during various biology/ entomology studies. Thus, trout rarely see a view of an upright mayfly, stonefly, or caddisfly drifting toward them with their wing case shown in perfect balance. Personally, one of the main reasons I think that fine tippets such as Scientific Anglers Absolute Trout will convince picky fish to eat, is that their suppleness allows artificial nymphs to twist and flail a bit more like the natural invertebrates do.
Contrary to what seems to be conventional thought, when nymphs are tied on jig hooks, the wing case actually faces the fish more often if it is tied on the top of the fly in the normal fashion. While the idea behind jigs is inverting the fly, this inversion is almost never a perfectly achieved in horizontal fashion. In my experience, the knot on a jig fly typically slides to the top of the eye after casting and fishing, even if it was tied in the middle of the eye perpendicular to the shank of the hook.
Butano Perdigon - Credit Devin Olsen (Tactical Fly Fisher)
With a Euro-nymphing rig, even if you keep a near vertical angle with your sighter (which most people don't in an effort to lead their flies and keep in contact), a slight bow in your tippet will develop below the surface due to drag in the upper faster layers of the column. Because of this slight drag, the tension placed on the fly will be in a slight downstream manner. This downstream tension inverts the fly with top of the hook pointed downstream facing potential target fish. However, because of turbulent currents, lateral drift, and leader angles across the stream (instead of just vertically under a suspension device or sighter), the nymph likely provides an oscillating profile that routinely shows and hides the wing case as it twists back and forth during the drift. Therefore, the wing case will likely make at least a short appearance during a drift toward a waiting trout, regardless of whether it is tied inverted on a jig hook or not.
Brenda Galey - Euro Nymphing the Rubicon, Victoria
Here are the last two and probably more important reasons to tie jig nymphs with wing cases on top of the hook in a normal fashion:
It is easier to tie jig or inverted nymphs with wing-cases in the normal upright fashion. Turning the fly upside down in the vice creates problems with the hook point getting in the way of materials and access for your fingers, which will likely have run ins with the hook point if it's upside down and you aren't careful.
Last and most importantly, I've tried both methods of wing-case placement with inverted flies. Those tied with wing cases in the normal fashion have fished as well or better for me than those tied inverted. Drift theory aside, this is the only real reason that counts much to me.
Lubomir Svabek’s - Promontakva
I've had plenty of response saying wing cases aren't necessary. Even if you fit in this category of belief, this post also applies to other fly additions like biots on prince nymphs, wings on flies like midge emergers, and shellbacks on stoneflies, scuds, and caddis larvae.
Space X Nymph - Devin Olsen (buy it now at Reel Fly Fishing )
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