Recently we had some discussion regarding whether we would be able to tell the difference between our existing F-1 Bass and the Northern Black Bass that we stocked a few months ago. There is a considerable difference in color and attitude. The Northerns are much more aggressive. Fortunately, now we will be able to cull our F-1 Bass without fear of taking any Northerns. In the two photos the F-1 is green and the Northern Bass is black/gray. FYI the F-1 shown is about 3 lb while the Northern is about 1.5 lb.
In all the reports and studies I have seen there is no mention of color being a differentiating trait. I have seen many thousands of northerns , F-1s and Flas and never seen color as an indicator. Keep in mind that color changes rapidly and often. Thanks for the info and keep up the tests and keep us posted on results.
To be honest, at least in our water types here, I have never seen a "green" largemouth. Universally silver/black, but that could be a lot of environmental factors such as cover color, water clarity, diet, etc. My fish in my aquarium will change on the fly with spawning and competition/dominance.
As far I know, I've never caught anything but northern strain LMB. My experience with LMB has only ranged from Northern Minnesota to Southern Virginia, to the Canadian border, so...
I've never tracked color. But, from casual observation, it sure seems that water clarity and temperature really has an effect on the color and contrast of LMB, BG, SMB, RES, black crappie, and CC. In cold water (less than about 40 F degrees), or in water with extremely low clarity, all of these fishes significantly change to very muted colors. I've not seen it with trout, yellow perch, walleye, pike, or musky.
From late spring through early autumn when temperatures are above about 60 F degrees, LMB seem to have green backs. This time of year, when the water is in the 30s and 40s, their backs are much closer to black.
In all the reports and studies I have seen there is no mention of color being a differentiating trait. I have seen many thousands of northerns , F-1s and Flas and never seen color as an indicator. Keep in mind that color changes rapidly and often. Thanks for the info and keep up the tests and keep us posted on results.
IMO, the only fair comparison to differentiate between LMB traits would be to hold them in a large holding tank to normalize conditions for comparison. As has been mentioned, they can change physical characteristics in a heartbeat..
I believe I can ID pure Florida traits by the “mottled” pattern on their backs after I leave them in the live well long enough to settle down. Only problem I have is that I don’t have a native or F1 to compare so I am just guessing.
N.E. Texas 2 acre and 1/4 acre ponds Original george #173 (22 June 2002)