What colors can trout see?

[DSFlyman]

So, 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.)

 

[dorian.ducker]

I attended a seminar on how Trout think about 3 weeks ago at a fly fishing expo in Bellevue WA. The colors that they said that Trout reacted to the most are the Reds and Greens. Peacock herl specifically has a property that makes it shimmer with UV light which supposedly is very attractive to fish. There was another color that fish predominately saw, but I can't remember it. They said that fish can discern between shades also, but aren't picky about them.

Just what I was told by some biologist/fish expert. Who knows how true it is.

 

[peregrines]

This is an interesting article. Because of the name of the site, "sexy loops" it come from, (though it doesn't show up in the hyperlink below) it's probably not a good idea to click on while at work, or you may get a visit from HR. (The name of the site refers to fly casting).

Salmonid Vision

The "take aways" from the article are that:

red is the first color wavelength to be absorbed usually by 15 feet or less, blue is the last (deepest)

Black provides the strongest contrast, and would be a good choice for deep or turbid water,

Fluorescent colors can have a big appeal (chartreuse, hot pink etc)

Some materials like peacock herl have "structural color" rather than pigmented color based on the way they refract light. Think of the head of a drake mallard-- it looks green, black purple etc depending on your angle. Perhaps that's one reason it's so effective in so many flies. This may also make a case for blending colors in dubbing and mixing colors of hackle... if you look at a baitfish for example on first glance it might have a "white belly" but if you look you'll see yellows, purples, pinks etc. based on the reflection/refraction of light.

Color is just one of several factors (shape, size, movement that might serve as triggers) and there is such a large variation in the colors of naturals, even within the same species in the same stream-- (even to the extent of the color of duns which tend to be dark when they first hatch and lighten up, the color of nymphs with dark wing pads just prior to emergence, as well as subtle to dramatic changes in color from stream to stream. Many in stonefly nymphs take on a rust color in streams with high iron content.) There can also be triggers that seem to be very effective (egg sacs on caddis and stoneflies, hot spots on scuds, hot tags like Green Butt Skunks for steelhead, etc.)

Trout's range of vision extends into the UV wavelengths.

As an interesting aside, some classic "old timey" dubbings like Hendrickson (from the stained underbelly of a vixen fox) and Tups (from the "indespensable" part of a male ram) are well established for their effectiveness. It turns out that urine reflects UV light.

There is a very interesting series of articles here, showing pics of mayflies in both visible light to us humanoids as well as pics showing how the same critters might appear to a trout able to pick up UV wavelengths:

Appearances aside, you are Not a trout...Part 1 - Trout and UV Vision - The Contemplative Angler

UV ice dub anybody.....?

From a practical standpoint a trout has to eat, and in fast water and with competition from other fish, there is probably not much of a deliberative analytical process going on. Keep in mind that "90% of what a trout eats is brown and 3/8" long..."

Mark

 

[swirlchaser]

I don't do much Trout fishing but I've learned from saltwater fly fishing that things like profile, the amount of water a fly moves and contrast are more important than the actual colors. IMHO A small reflection, contrast, and the right profile will generate a strike no matter what color material the fly is tied with. At first light or even at night with little or no light large, black flies that move lots of water generate tremendous strikes. I am partial to certain colors but I think thats just for my eyes, not the fish...

 

[Rip Tide]

Gary Lafontaine's Theory of Attraction has to do with the different characteristics of flies that can trigger a response from trout including the relationship of light and color.
Here's a link to the chapter from his book The Dry Fly

The Dry Fly: New Angles - Google Book Search

 

[DSFlyman]

Awesome info - thanks