Pond Boss Forums INTRO Questions & Observations My Blond Bluegill Question

I am catching BG now here in S Origun, and though comming through the winter looking very healthy, they all seem to be rather 'blond' looking, very light in color throughout their body and head. Any knowledge on this??? The Bass look normal, but happily fat with eggs.

Sunfish color, including bass and bluegill, is typically influenced by water clarity and nutrition. Muddy water yields light colored fish. Clear water influences them toward darker colors. During the spawn, males become much darker and rich in color, while the females fade in color a bit.

Thank you, Bob. That makes sense, for I am fishing (C&R) over their favorite spawning bed area and I might be catching all females. I'm not so hot at identifying sexes yet.

A fascinating subject and probably more than anyone wanted to know about fish color including changes. As I read the description I could picture the changes occurring just as I have seen it many times.

http://www.wetwebmedia.com/AqSciSubWebIndex/coloration.htm

http://www.clarku.edu/departments/biology/biol201/2002/CSantos/Colored%20Chromatophores.htm

Long before aquariums we’ve known that fishes change color in response to their background, and that they change color during exercise and courtship. These changes in appearance are under the control of pigment containing cells called "chromatophores".

Some examples of this loss of dark color are ... sunfishes (Lepomis) that can quickly blanch from dark to light or come back again given fright or excited states.

Chromatophore changes can be divided into two categories, morphological and physiological. Morphological changes are usually evoked by maintaining an organism in a given setting, on a specific background for a number of days.
Physiological color changes involve alteration of pigment granules causing dispersion or aggregation consequent to various stimuli, e.g. light, temperature, chasing.

The control of aggregating and dispersing of pigment granules is caused by changes in the chromatophores ionic charge. A change of charge within the cell causes a change in color. There are two ways to change the ionic equilibrium within chromatophores, hormonal and neural. Both "paths" are often employed, one working more gradually, the other more immediately. For example, the time required to change from light to dark varies immensely.

There is good evidence that melanophore control by advanced bony fishes is principally actuated by the autonomic nervous system.

There are two principal chemicals that are produced and release by neurons (neurohormones) that affect color.
Epinephrine (Adrenalin): A nerve-activated hormone that’s released by an organism when it is excited or scared, causing pigments to contract and the animal to blanch, lose color.

Acetylcholine: A chemical that is active in muscle tissue, movement, almost always causing melanin to disperse, darkening the organism.

Morphological color changes are due to amounts of pigment present in the chromatophores of an organism. Morphological changes occur very slowly, generally over the course of a month or more, and are usually permanent.

Types of chromatophore are characterized by the color they carry. Erythrophores contain reddish pigments found in carotenoids and pteridines. Melanophores contain black and brown pigments called melanin. Xanthophores produce yellow pigments in the form of carotenoids. Fish are capable of producing some pigments, but others must be supplied in the diet. For example, they cannot produce carotenoids naturally. They accumulate carotenoids from their diet and transfer them into pigment cells to produce red, yellow, and orange colors. The intensity of the pigment is reliant on the quantity and types of carotenoids supplied in their food. The carotenoid pigment found in most marine invertebrates is astaxanthin. Another pigment that is derived from a food source is phycocyanin. This pigment is blue and is readily found in blue-green algae. Additionally, the ability of fish to store pigments they have acquired from their diet will greatly affect their appearance.

Various hues are made possible by the combinations of different layers of chromatophores. Cells carrying more than one pigment are called compound chromatophores. Most fish that appear to have green coloration on their scales actually have a layer with yellow pigment and another layer on top that scatters light and reflects a blue color. There are other types of chromatophores that do not retain pigments .

Note that there are two types of pigments true or based on color and reflective. Also note that not all chromatophores contain the actual pigment color that they appear. That is, that some work on different principles other than selective absorption/reflection. The iridophores contain quanine crystals that reflect different wavelengths of light, which give them an apparent color though no true pigment is present. Further, there are two types of iridophores or reflecting pigment cells, ones with decidedly larger and smaller quanine crystals. The larger crystals can change their orientation to reflect different colors of light. Cells with the smaller crystals can aggregate or disperse their pigments thereby controlling the intensity of color.

Because iridophores are typically light in color, the effect of dispersion and contraction is opposite that of melanophores. When quanine crystals are aggregated, the cell appears darker. The plate-like crystals give off iridescence as seen on the top and flanks of many fishes (e.g. Silver Dollars, Metynnis, Mylossoma, Anchovies, Engraulis).

Green, gold, red, blue and many other colors can be reflected selectively by iridophores. The iridescent blues of Neon Tetras (Paracheirodon innesi) are a result of quanine crystals for instance, and not blue pigmentation.

Fishes also utilize combinations of pigment cell types, with iridophores and melanophores mixed.

Much more in the links.

Good stuff, ewest! When I first mucked out the pond and then started my fish populations, all I had on my mind was meat and fun catching it. Though that is still in the big picture, raising fish has become more of an 'observer sport' for me, and even watching the seasonal color changes is interesting. Thanks for the indepth info.

Ewest,

That may also explan why exclusively pellet feed bluegills tend to be lighter then their wild counterparts that are getting other things in their diets.

My bass which are pellet feed are very pale even though the water is crystal clear.

Condello has reported (to me at least, maybe not on the forum) enhanced PBR BG colors when he changed their diet to pellets + krill, instead of just pellets. The assumption was it was due to the increase in (the range or number of) natural pigments in the diet.

Theo,

In my grow out tank, I use a sinking feed from Aquatic systems because it is so great on the fish...but a side benefit are the spectacular colors it seems to promote in fish. Check out the Tilapia and Pacu on my web site. The Tilapia are redish in color and the Pacu simply spectacular. The feed is called New Life Spectrum and it isn't cheap, but seems to be really good.

Interesting note to you all...I am working with Dr. Mark Griffin with his new largemouth bass food. I asked him a question last week about what kinds of vitamins, etc, he could add to feed to enhance the color of feed trained fish to a more natural color. He is adding some betacarotene and some other color enhancing nutrients to a batch of feed. We are going to do an experiment with feed trained bass this summer and see if it makes a difference.

Take some pics (in the water and out) so we can see the results.

For those of you that are new to this forum, this type of technical thread probably wouldn't have been likely 2-3 years ago. This shows how much this forum has grown in the past few years.

Let me expand this discussion a bit. From your Easter egg days, you might remember that the color green is made up of blue and yellow. That means that if you see a plant, bird or anything else that is green, you always have blue and yellow. If you take away blue, you have yellow. If you take away yellow, you have blue. Go to a pet store and look at parakeets and you will see this. Bird breeders do this with lots of species and we have a huge variety of colors in birds. This is also true of plants. You might have seen "blue fescue" or "yellow switchgrass". This is for your trivia discussions.

Norm also fish have multiple layers of color and some cells have the entire prism which can be changed. Iridophores contain quanine crystals that reflect different wavelengths of light, which give them an apparent color though no true pigment is present. They give off iridescence.


Here are some color differences in BG - same pond - same time (all with in 30 min.)- same diet(?). Some of these fish changed colors in the few seconds from the water to the boat.






















Colorful aren't they.

I think Eric must be posting from work.

Opps . Fixed now.

Would this one be considered a blond BG?

Shorty, mine are actually pale, almost translucent, with no dark color at all. The water is warming up and I'm getting a lot more activity, so I'll be keeping an eye on them as much as possible to see if there is any change. I have had them off the feeder all winter, but I am just this week starting them back on pellets, and it sounds as though that could be an influence.

Shorty your's looks normal colored to me. Here is a blond one that Bruce posted.

I know ewest, I was just looking for an excuse to post my picture again. That and I was thinking about "natural" blonds vs. "bleach" blonds. :p