Two Recent Scientific Discoveries Impact Midge Fly Design

[troutracker 0]

 

Image shows a sunken adult midge Pattern, the Blue Wing Midge, tied to show WIPs-like colors. Since their discovery in 2011 (Shevtsova et al, 2011), Wing interference patterns (WIPs), which cause patches of vivid colors on midge wings, have been now identified in 58 species in the midge family (Shiyang et al., 2023; https://doi.org/10.3897/jhr.96.111382) The Blue Wing Midge design also considers that sunken adult midges are becoming more important as fish food because pollution, including man-made surfactants, have a two-fold effect: increasing the proportion of midges in streams as well as causing an increased failed emergence because of reduced surface tension (Takamura, 1992; among others). 

For scale: Th total length of this fly from hook eye to the hook bend is about 7mm across.  The tip of the vise jaws are about 3 mm across. 

 

Video explaining what WIPs are and their use in fly tying and fishing is posted at: https://youtu.be/uQhpxvoJ-fk

 

A portion of a Diptera wing showing WIPs.  Image credit: Грибков михаил, used under Creative Commons license 4.0, via Wikimedia Commons

 

[troutracker 0]

To expand on the impact of WIPS on fly design: The recent discovery of WIPs (in 2011) makes the bright colors that we tiers have by trial and error added to flies—seen as pink hot spots, magenta hi-vis wings, blue abdomens and such—as colors that could be related to a natural phenomenon.  Light waves passing through thin transparent membranes, like aquatic insect wings, can subtract or add to each other and produce a hybrid wave whose resulting wavelength our eyes see as a color or no color at all (cancel each other out). The exciting deal is that these hybrid colors may actually be "matching the hatch" for some insect families. The midge hatch in particular has a more colorful aspect than we previously thought justified. 

As of 2023, scientists have been identified WIPs in some 58 species of the midge (Diptera) family. So vibrant wing colors are widespread in midges and ultimately may prove to be characteristic of midges.  Studies of other insect families are also finding WIPs. It seems any appropriately thin, transparent insect wing can potentially show WIPS—but depending on the wing thickness and light source may or may not be visible to the trout (or less importantly to us). 

So tie one on and see what the trout say. 

I know WIPs colors work well on the blue-wing midge (BWM) pattern fished as a dropper on a two-fly euro nymphing rig. But I expected the fly to look like trout food given the number of images of the naturally-occurring blue-wing midges I was able to compile from sources around the world—a few of which are shown in the BWM tying video.

[Heff2 0]

Fascinating,  do we now if fish, trout specifically, have the ability to distinguish this?  

[SilverCreek 0]

Trout essentially see the same colors that we do but they see very poor detail since the trout retina does not have a macula.

Read Gordon Byrnes article on trout vision:

https://www.flyfisherman.com/editorial/how-trout-see/454967

[troutracker 0]

1 hour ago, Heff2 said:

Fascinating,  do we now if fish, trout specifically, have the ability to distinguish this?  

To summarize what I have gleaned from reading up on the somewhat controversial subject: what we think we know about trout vision at present-- is that it appears that Wing Interference Patterns (WIPs) do occur in wavelengths of light that trout can detect and perceive as color.  Note that WIPs  are best viewed against a dark background because while the interference colors are vivid they are not bright. 

WIPs 

[SilverCreek 0]

Epistemology is the theory of knowledge. It is the study of how we justify what we believe to be true. 

Even if we did not know that trout see the same colors that we do, the simple fact is that we can only imitate what WE SEE.

Suppose that trout could see into the ultraviolet or infrared spectrum. How can we imitate that color if we cannot see that the natural insect reflects colors in that spectrum. The obvious answer is that we cannot. We cannot know what we do not know!

[troutracker 0]

23 hours ago, Heff2 said:

Fascinating,  do we now if fish, trout specifically, have the ability to distinguish this?  

I interpret the frequent response of trout striking the Blue Wing Midge pattern as that the trout seem to accept that sunken adult midges have this sort of coloration.

[Heff2 0]

4 hours ago, troutracker said:

I interpret the frequent response of trout striking the Blue Wing Midge pattern

That is research enough for me to give it a shot 

 

On 4/9/2024 at 12:50 PM, SilverCreek said:

Epistemology

While I had heard this term in the past, you referencing encouraged me to review it.  Led me to the Venn diagram explaining this which, for me anyways,  really provided some perspective

Thx silvercreek.