Question:
When the color of a largemouth bass is white and
faded looking does that mean that he has been in shallow water or
down deep. I might be wrong but I heard that when they are down deep
they become light in color.
Replies:
Hi Ricky,
You are partly correct. Largemouth bass have photo receptors in their
eyes that help them cue the changes in their pigment cells in their
skin. Their eyes receive the reflected light from their surroundings
and this can trigger a chemical release (hormones) in their skin to
move the pigment closer to the surface of the skin or further away.
This is an adaptation that allows them to camouflage themselves
better when they are hunting prey or being hunted by larger fish. If
they are in clear water with good vegetation/cover they usually will
take on a darker color on their back, green on their sides and white
on their belly. This is when they also have the beautiful green
horizontal bar across their side. When they suspend out in deep water
or even in shallow muddy water they will take on a more
faded/bleached out appearance, it can even be a buttery color. This
is because their only cover is either each other in a school or the
open water. When they are in shallow clear rocky or wood cover with
no vegetation they can also be more black and white. By having a
more uniform color appearance in open or muddy water they are less
noticeable by predators or prey.
So when you catch a fish in shallow clear water and the fish is more
pale in color it did in fact most likely "come up" from deeper water
or from being suspended off shore unless the water is cold and muddy.
Most color changes can happen fairly quickly (less than a day.)
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