Difference in brown trout colors
- This topic has 21 replies, 14 voices, and was last updated Aug 21, 2007 at 1:28 am by
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I see a lot of variation in brown trout color. I have noticed (from pictures) that western browns don’t have nearly as much deep yellow and orange on their lower bodies and fins as Michigan browns do. It’s a very interesting post. Can’t wait to hear more. Bet it’s either food or its genetic. Or maybe water chemestry, or maybe temperature – heck, I don’t know.
Bob
I don’t know if it would be the same for browns as it would be rainbows, but I have seen big color variations in rainbows due to what they are feeding on. For example, last summer I was fishing in Mo and within 100yards of water I cought 2 fish that were strikingly different in color. One was your typical missouri rainbow and the other had bright copper on it’s gill plates and a deep red line with tons of spots. The second fish was caught on a hopper. Every time I go back to this spot I find this fish and he is always feeding on terestrials. Somone once told me that there is a chemical in beetles and other terestrials that can affect the color of a fish. This may not be true however, I am not biologist. The other possibility that was suggested to me is thus: the particular creek I was fishing has been stocked with some of the pure McCloud river rainbows, I guess it is possible that this fish was one of those or an offspring of such. Maybe somone with more knowledge can shed a little more light.
Hey Gary –
I have also noticed the extreme difference in the amount of red/ochre tones in fish caught in Arkansas (where they can be almost orange) and in Montana (where most seem to be sort of cerulean to teal blue).
Zach, I don’ t have the biochemical contents in front of me, but crustaceans in general, have much higher carotinoid content than other aquatic prey including insects.
This is a decent illustration, but i;ve seen them where they have lost even more color.
http://fishing.about.com/od/troutandsalmon/ig/Trout-Pictures/Lake-Michigan-Brown-Trout.–GR.htm
Z, I have to go teach now, but that coloration is typical of lake fish — predation is very important and so there is strong selection against external coloration that isn’t “counter-shaded” (i.e., light below and dark above) — think of pelagic marine fishes like tuna and marlin.
Of course we all already know about spawning colors as well, fish can change colors based on hormones that are released or due to environmental stresses.
That is true, Spencer, and the Madison brown above was taken in August, with no pre-spawn activity, while the Little Red Brown was during the early fall (I think in early October), when pre-spawn activity was starting and the fish were beginning to color up.
I agree more that the color is probably due to what the trout is consuming but has anyone ever heard of the concept that darker browns tend to feed more at night, thus their darker color? This was something I heard a local guide say some years back. I can’t say I’ve ever heard any factual evidence to it though.
Gary, that’s good stuff and Zach tells me you’re without a doubt an authority on this stuff.
What do you know about redfish (red drum)? Sometimes the fish have dark crimson backs with white bellies and other times it’s more like a very washed out khaki. Like many freshwater predators they have a very mixed diet of baitfish and crustaceans. I’ve always thought the level of red on them could be directly related to the amount of crustaceans in their diet but have never gotten an answer much above local, backwoods lore.
Just something I’ve always wondered.
Gary G-Not typical of the fish on the creek. Those two are thin. They are the exception. Just good examples of color difference for illustration purposes.
Thanks everyone, for the input. Good stuff.
EDIT: Yesterday or the day before, Moosedog called the fisheries biologist we have here. He’s kind of on retainer for stream rehab work, water monitoring etc. Moosedog posed the same question to him. Here’s his short version answer.
Genetics and environment both contribute greatly to skin color of trout. Brown trout even have the ability to change colors to match their immediate environment rather quickly. Within 7 to 8 minutes a brownie’s color can change to help with concealment. He said if a fish moves into a different holding area, his colors will change to match the colors of the stream bottom where he is now holding. It’s a protective mechanism to help against overhead predators.
Matches with the fish above. The lighter colored fish was caught in a very light colored stream bottom area. The dark fish came from a very dark pool. Deeper and big dark boulders on the bottom.
I also googled up the subject. There are many links that basically say the same thing about skin color. Here’s just one quote from a page on http://www.gsmnp.com/pages/brown.html
Brown trout are also unique in that they are able to change their color quite rapidly as a means of concealment. Brown trout are also the only fish ever to rest on the stream bottom. This also explains their success in many waters: They are just plain hard to spot both by predators and fishermen. NOTE: The color changes mentioned refer to changes in the background color of the trout’s skin–they can’t change their spots.
Guys I know one thing it would be pretty boring if all browns from even a certain run in a stream or river looked alike, just as it would be if we all looked alike.
Ron,
I believe everbody is wrong, I think they were caught on two different color hoppers I sent you, what you think?
Got me curious and looked up an older book by Cecil Heacox, “The Compleat Brown Trout.” It has a discussion on this on pp. 29ff.
He says in short, “the brown trout does not have a standardized appearance” and “Throughout its range, original and adopted, a brown’s color varies in different locales and habitats; sometimes from stream to stream and, not infrequently, in the same stream.” He then alludes to the camouflaging ability Gary mentioned above.
One thing of note is he says a touch of color in the adipose fin is a fairly reliable indicator for identifying wild browns.
Beautiful fish they are.
Scott
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