What colors do trout see?

I think fly fisher-people like many other folk have our superstitions. I’ve heard it said that fishing with confidence makes all the difference. Does this mean that the same fly fished the same way with two different anglers will catch a different amount of fish because of some fishy mojo?

Well, either way, my curiosity has brought me to color.

I recently posted about my fly with a dark green glass bead head. I had thought in the store that the beads were black, and after tying up some midges with them, I became concerned that their green hue would put off fish.

Well, there were several threads where people piped in and suggested that water actually changes the quality of light, or at least how it is reflected off of colored surfaces. It was suggested that red is the first to lose it’s color tone in the water.

I tie several baitfish patterns that use red thread either behind the head or for a head. From my understanding, that color is supposed to suggest the gills of the agitated fish. Red has been used on several other patterns as well to attract fish for decades. The Royal Coachman is a perfect example.

Any science minded folk have the current skinny on how trout see color? Based on what I keep reading, it almost seems like we could tie everything in black and shades of gray (I would never stoop to such a heretical level myself.)

I hope you get some good responses. I’m interested in this subject as well. I use red a lot.

The best explanation I ever read was in a book called The Trout and the Fly, by Brian Goddard and John Clark:
http://books.google.com/books?id=CS_oGwAACAAJ&dq=The+Trout+and+the+fly

It explains alot about trouts’ visual perceptions. My recollection is that they do see in color (more than we do) but their visual definition is not as good as ours. It has to do with rods and cones in the eye.

Anyway, I recommend it as a great read.
:smiley: Tight Lines!!

Here is my response to that , no matter if they see in shades of gray to black or color, because if they do see from shades of grey to black, the natural color will still produce a shade that could not be exacted by a grey or black because the color itself will produce a shade that could only be duplicated with the color that it is, a similar shade of grey or black for red will only come close and not produce the exact shade because it is a different color, the color in itself will be producing its on shade. In order for us to tye with the correct shade of gray to black for red, we would have to first see the color threw something just like the fishes eye to see what that would be, when I can use my natural eyes to see red and just use red, that’s Just my O2…

My understanding is that trout see colors we see plus UV colors we don’t. The trick is figuring out how their little conditioned minds interpret these matters

Although red dose fade to black quicker than other colors as you loose light in deeper waters, it shows up well in most of the crystal clear waters that trout inhabit. I’m sure that colors dim in shadows for fish as they do for us and in the depths of deeper lakes I’m sure that colors also fade. For the most part, however, I believe colors do make a difference.

As light moves through a medium there is some lengthening of the wavelengths. Water much more so than air and longer wavelengths (red end of the spectrum) more than shorter. As the waves lengthen the perceived colors change toward the red end of the spectrum.

Fish see the colors as constantly changing based on whether they are approaching or departing the light source.

Since shorter wavelengths are less affected they travel farther and change more slowly than reds. Fish see those lighter and brighter colors, all the way into UV farther than the longer colors…

But also, black blocks all colors and fish can see those profiles blocking a whole lot of light we are completely unaware of, which is why black is such a great color, even at night. It both blocks and fails to reflect. It is the reflected light which limits the ability of fish to see the colored stuff in the dark.
art

I remember a video on youtube, where the fellow was tying up a beadhead egg type fly. He was using yellow and black, I think he called it a steeler bug or something like that. When asked why he liked to use balck and yellow he made reference a study that stated out of all the color combinations of food offered to trout that yellow and black were the most successful. I can’t recall everthing the gent said about the study. I think the experiment was in a controlled enviornment so with regards to light availability at certain depths it might not apply as it does in the wild. I think the reason why yellow and black might be effective is that it represents both light and dark shades.

Well, I waited, but no longer. Consider that various specie may perceive different colors and do so differently. Some may be able to recognize, for instance what we call blue, at differing times (coming into fresh water from salt water) or living at varying depths or at sexual maturity. The rods and cones may vary in ratio among specie, or from deep water fish to stream types. Add wave length widths and the question becomes unanswerable. The eyes of chum entering fresh water at spawning time develop the ability to perceive green before all other colors.

I listend to a professor talk on flyfishradio.com that purple is the most effective colour becase if you drop it in the water it will be the last colour to disappear out of all the colours.
but the most effective colour i use is gold, for some reason around my area they love it. any streamer with a gold body works great.

mike

Here is my response to that , no matter if they see in shades of gray to black or color, because if they do see from shades of grey to black, the natural color will still produce a shade that could not be exacted by a grey or black because the color itself will produce a shade that could only be duplicated with the color that it is, a similar shade of grey or black for red will only come close and not produce the exact shade because it is a different color, the color in itself will be producing its on shade. In order for us to tye with the correct shade of gray to black for red, we would have to first see the color threw something just like the fishes eye to see what that would be, when I can use my natural eyes to see red and just use red, that’s Just my O2…

Holy Moses Tim! WTF?

JC your comment is interesting. I have seen many men fighting to their virtual deaths over this topic on the web.

One thing is for sure despite all the science that is available on the subject based on research and microscopic examination. That is that any conclusions are subjective in nature because we can only base them on what WE see and our knowledge of what the rods and cones mean in US.

Sure fish will see colours and there will be variances at certain depths due to reflection and refraction and light absorption and water clarity and movement; and even then it is only a small part of the behaviour of the fly and a whole raft of the other feeding triggers and of course some “luck!” and being in the right place at the right time with the right fly behaving and looking the right way. And, the fish has to be the right fish.

Remember what colour a carrot is while it is underground, before it is exposed to light? Nobody knows.

If you really want the answer to what colours a trout does or does not see, you can make assumptions based on science, but you really have to ask a trout!

I can’t really be the voice of reason here can I? When we ty a fly that represents a certain food item that we know the trout eat, don’t we use the color [we see]that matches the food item? If we can find the same color match, I don’t think it matters what color the fish can see. I will look like the color that it has been eating, and therefore its the right color.
Gary

Gringo my friend? “If you really want the answer to what colors a trout does or does not see, you can make assumptions based on science, but you really have to ask a trout!”

lol didn’t I say the same thing?
In around about way? If the fly I want to imitate looks red to me, then I may as well just use red…:slight_smile:

More than you ever wanted to know about light and fish vision.

Light frequency stays the same and the speed of light is a bit slower in water than in air, therefore wavelength or color of the light does change a bit as light moves from air to water. However, I think that has a relatively small effect.

What has the greatest effect is how deep the various wavelengths or light colors penetrate water.

The doppler effect, or red shift that astronomers see in stars moving away from us, has very little effect at the speed that fish swim toward or away from an object. Colors do not shift for fish just like the color of a car coming toward us does not look any different when that car is going away from us. That car is moving at a greater speed than any fish, and we don’t see any doppler shift because the speed of the car relative to the speed of light is so small that we cannot perceive any wavelength change. So whether a fish moves toward or away from a fly, there is no doppler shift effect.

The fact that fish can see into the UV spectrum has nothing to do with the penetration of light but the ability of their cones to detect into the UV spectrum. If they could not detect UV, it wouldn’t matter if UV were present or not.

What the fish sees is dependent on three factors. One is the depth of light penetration which varies with wavelength - ROY G BIV for Red Blue Yellow Green Blue Indigo Violet. The red end of the spectrum penetrates the least and if I remember correctly is gone by about 5 feet. The other factor is the color of the fly. Obviously, if a fly is green it does not look blue even if blue light may be present. Only the color that is reflected back to the fish can be seen by the fish. The other colors are absorbed and only green is reflected. The final factor is how much the reflected color of the fly gets absorbed by the water between the fly and the fish.

Therefore, the presence of light of a given color is a necessary factor but not a sufficient factor for the fish to see that color in a fly. The color light must be present, the fly must be of that color so that that color gets reflected back to the fish, and the fish must be close enough to the fly for the reflected color to gets back to the fish.

Fish do not have a macula which is the region of our retina that are tightly packed with cones. Their retina are evenly coated with rods and cones. The density of the rods and cones is 14 times less than in a human’s macula so we see 14 time “better” than a fish. A fish needs to get very close to a fly before it can see the detail we can see at a distance.

A trout has a round lens when compared with a human lens which is more disk shaped. Because the lens of a trout must focus light that enters the lens from water, it needs to be more spherical than a human lens which bends light entering from air. This allows the trout eye have a wide depth of field - i.e., the shape of the lens does not need to change much to focus for a specific distance. So to a trout virtually everything is in focus. Perhaps this explains how they can pick some things out even though we are able to see greater detail.

Finally, no one has mentioned flourescent or phosphorescent flies. Flourescence is the ability of a dye to absorb the light energy of one color and emit an entirely different color. Therfore, even if all red light gets absorbed below 5 feet of depth, if we use a flourescent red material, it will absorb blue light energy and emit a red color.

Phosphorescense is the ability if a material to absorb light energy (usually in the UV range) and gradually emit it over time. It differs from flourescent material in that a flourescent fly cannot store the energy and emit it over time. So if we treat a phosphorescent fly with a UV LED light source, we can fish it at night and it will glow under water. I use phosphorescent strike putty at night to locate my flies when fishing the Hex hatch.

I met Roy in 1948, him and some basic algebra. :slight_smile:

Check out these thesd discussion(s) and photos of underwater flies.

http://www.danblanton.com/viewmessage.php?id=118568

http://www.danblanton.com/viewmessage.php?id=118501

Silver
Your statements about doppler show you missed what I said…

Water has a far greater effect on light and murkier water will rapidly affect the color and intensity of light, shifting it toward the red end, but approach speed gets absurd fast…

The fact you know how fast red disappears should give you a hint how that works…

Fishes’ abiliies to see UV have everything to do with light penetration. They see it because it is important to them because it does make it much farther through water.

As it was explained to me, there are entirely different sensors for UV with much smaller and less angled receptor surfaces to catch UV. It is not the same old cones carrying over into the UV range.
art stopping here…

Can you explain more completely what you mean and how a red shift occurs in murky water, and what you mean by “approach speed”?

that reminds me of a red colored fishing line, that “disappears” at depth because red light doesn’t penetrate as deep. The problem is that the only thing that disappears is the red color, when in fact, the line now is black rather than red, so more visible than ever. Flies may lose their color at depth but the fish can for the most part still see them.

If you fish every fly in every fly box you have and none of them catch any fish …

YOU will see RED !!!

But the fish won’t mind because …