Meanmouth Bass

[Flysmallie]

10 hours ago, Gavin said:

 It is pink not bubblegum.

Thank You!!  I can't stand stupid color names.

[Walcrabass]

Straw Hat,

  Very well put..... and along with the alleles that are spoken about it all makes sense. That is why when we have fish like the Wonderful little ( please put emphasis on little) Kentuckies that you can get fish from other offspring on down the road that are far "worse" than either parent. Simply put it degrades the ancestry of both parent species. I can tell I am REALLY going to like this post. It will get very interesting before it is exhausted.

 

Wally

P.S. All of you that may have told the people taking the survey concerning the "Spots" or Kentuckies in Stockton please follow these posts carefully.

[straw hat]

http://link.springer.com/article/10.1007/BF00485797#page-1

The inheritance of tissue-specific lactate dehydrogenase isozymes in interspecific bass (Micropterus) hybrids.

I looked into this article. It deals with the genetic source for the development of lactate dehydrogenase isozymes in the fishes eye. Lactate dehydrogenase isozymes are used by cells to convert lactic acid to pyruvic acid. These two help to control the NADH cycle. NADH is part pf the energy transfer mechanism in the cell and is part of the driving force of many of the cells function. These isoenzymes, while occurring in the eye (as well as other body parts, is not related to eye color.

[straw hat]

"Genetic and in vitro molecular hybridization of malate dehydrogenase isozymes in interspecific bass (Micropterus) hybrids".   Wheat

This article is similar to the one above. Malate dehydrogenase  (MDH) is an enzyme that reversibly catalyzes the oxidation of malate to oxaloacetate using the reduction of NAD+ to NADH. Again this process relates to energy activity within cells. The one thing to note in this article is that half the enzyme produced in smallmouth/largemouth hydrides are the same as for smallmouth and the other half the enzyme is the same as for the largemouth. This is the first time that "molecular hybridization" has been found in bass hydrids.

While this enzyme is not related to eye color it could certainly be that the gene for eye color in smallmouth and largemouth may act the same way with the resultant pigment in a hybrid chemically half way between the pigment for largemouth and smallmouth.

[straw hat]

I looked everywhere I could think of and could find no specific research on eye pigments in largemouth or smallmouth bass BUT here is what I found.

http://www.annualreviews.org/doi/abs/10.1146/annurev.ecolsys.27.1.543

There are four main pigments found in the eyes of fish. Each pigment is known to mutate easily. So there may be many shades and tones of red for example.

Rock Bass and Redeyed Bass are the only two species of Centrarchidae to commonly have red eyes. These have been shown to be dominant when the species cross with largemouth or smallmouth bass but the resultant hybrid looks considerably different than either the largemouth or smallmouth.

I also red many bass forums where I did a search for bass with red eyes. I noticed that many people note that the red eyes are more common during the spawning season. Any angler is familiar with the fact that hormonal changes that time of year can greatly effect skin pigmentation as well. I also noted that this phenomena was most common east of a line from Minn to Texas. I never found any mentions in the bass forums in the west (as of yet). I will look into that more closely though.

More to follow.

[straw hat]

Well it is strange. I looked at several of the California forums and found no reference to red eyes bass BUt in the western bass fishing forum There were many references including California.

http://www.westernbass.com/forum/search.php?keywords=red+eyed+bass&sid=6993018aa610427036a9e30a77962985

Many of these fisherman also related to this being more common in the spring spawn.

[Hammer time]

Catch and release all bass, be it Largemouth, smallmouth, kentuckies, or meanmouth!

Mother nature will take care of things as she alway does! Mankind steps in and tries the best to regulate length limits and numbers allowed to keep. MDC is one of the best conservation agencies in the USA and is on the pulse of all issues that arise and do their best for the environment.

Bass of all species should be handled carefully so future generations can enjoy catching some as we have the opportunity to now!

Tight lines and CPR 

Hammertime

[Al Agnew]

About the red eye thing, especially when it comes to smallmouth...the red pigment is always there, and as far as I know, all smallmouth have some red pigment in their eyes.  But there is also a lot of dark pigment in small structures that expand and contract in response to background light levels and other factors, and this is true all over the fish's body.  The next time you catch a red-eyed smallmouth, take a look at the color of its body.  Chances are it will be very light and brassy in color.  Chances are also good that you will have caught it out of clear water over a clean bottom.  Red eyed smallies are most commonly seen in Ozark streams in the clearer streams without much algae growing on the bottom, and more common in the winter and early spring before a lot of algae has started growing on the gravel and rocks.  This appears to be a function of an overall color adjustment to allow them to blend into the color of the bottom--bright gravel bottom, bright, light-colored smallmouth.  The structures holding the dark pigments, both in the eye and in the rest of the body, have shrunk and allowed the red to show through.  As the water gets darker and bottom covered with darker algae, the dark pigment structures expand and obscure the red pigment.

It's highly doubtful that this color change is voluntary on the part of the fish; it's probably a response to light levels more than anything else.  Sunlight hitting a bright bottom floods the water and the pigment cells are affected by it.  The fish evolved to be able to blend into its surroundings--those that blended in escaped predators and ambushed prey more effectively.

The cell structures also expand and contract in response to excitement (including sexual excitement) levels.  Smallies in the throes of spawning usually are very strongly marked with vertical bars and spots, while those that are feeding or just hanging out don't usually show strong markings.  Hook them, and the stress of the struggle often brings out stronger markings.  Put them on a stringer for a while and the stress really makes the markings stand out.

I was glad to see Wrench's link to the article about the so-called meanmouth, that pointed out that the originals were laboratory crosses between largemouth and smallmouth, and were so-called because of their aggressiveness even toward humans in their water.  I remembered all that from articles in Bassmaster magazine back in those days, and have been pointing it out ever since.  Everybody calls smallmouth/spotted bass hybrids meanmouths these days, but that wasn't where the name originated.  In the streams of the Meramec basin where hybrids are pretty common (and also in small streams running directly into the Mississippi in eastern MO between St. Louis and Cape Girardeau), they vary a lot in appearance, probably due to whether they are first generation hybrids or back crosses with one or the other species.  You see some that look almost like pure spotted bass (usually the only difference is a bit more brassy color and a bit less prominent horizontal stripe) and some that are very difficult to tell from smallmouth (usually just a slightly more greenish cast and barely a hint of the horizontal rows of spots on the lower sides).

The article Wrench posted mentioned that biologists were able to cross largemouth with green sunfish, war mouth, and bluegill.  I've caught a couple of hybrids over the years that I just assumed were smallmouth X spotted bass, but they sure looked different in color and markings, though completely bass-shaped.  I have pictures of one, but it's too much trouble to find them and post right now.  But now I'm wondering if these might have been rare crosses between smallmouth and one of the other sunfish species...kinda marked like some of the hybrid sunfish (bluegill X red ear) that I've caught.

[straw hat]

You could be right Al. What surprised me is the lack of research on eye pigments in bass. A lot of articles on vision but not on pigments.

Hammertime, I am in complete agreement with your principals but would add that the bass populations created in the lake are artificial and man made. With the exception of oxbow lakes, swamps and a couple other exceptions bass occur in running water (streams, rivers, etc). When man makes a dam it drastically changes the habitat and the fish population shifts accordingly. A man made population change if you will that is not natural.

 

[Al Agnew]

Here are a bunch of photos of smallies I've caught at different times...all are Ozark stream fish.

21 inch summertime fish...note dark bronze color, dark eyes, dark, algae covered bottom.

Compare to this 18 incher, also a warm weather fish but very light in color, eyes fairly red.

A smaller wintertime fish, very red eyes, light color that matches the clean gravel you can see on the river bottom in the clear water.

Another winter fish, again light colored, red eyed.

Exceptionally red eyes, light color, no dark markings showing at all (remember that the same mechanism that makes the eyes go dark and obscure the red also makes the dark bars and spots on the body show up.

A couple more examples of fish with the dark markings totally obscured and bright red eyes.

This one is the same thing, no markings, red eyes...but it was caught in very murky water, which also tends to make the fish turn very light in color.

Just a hint of red in the eyes of this 19 inch winter fish, but note the dark markings are showing up pretty well...again, same mechanism that obscures the red in the eyes and makes them dark, makes the dark markings on the body show up.

A darker summertime fish with no clear markings.  You can just barely see a bit of the red in the light ring around the pupil of the eye.

And finally, small fish like this little critter are sometimes seen on clear streams in bright sunlight, little smallies that look almost completely black in the water but immediately begin to lighten if you catch one.  However, I think this photo shows that the red is always there...you can see a bit of deep red in the eye, due mainly to the sun hitting it so strongly that it somewhat goes through the dark pigment and picks up the red.

This last one is kind of the exception that proves the rule...a very light colored, faded out fish but with dark eyes!