By: Leo Watson
A basss sense of sight is obviously a primary influence in its behavior. Without
good eye sight, bass would have a very short life span. There have been extensive studies
done to determine just how well a bass can see, whether they see in color or black and
white, and whether they see better at night or during the day. Tackle companies, as well
as biologists, and fisherman alike have an extreme interest in the answers to these
questions.
Eye sight plays an important role in the daily activities of all predator fish. In most
situations and conditions, sight is the dominant sense used in seeking and selecting food.
The photo sensory cells in a bass retina consist of cones ( for color vision ) and
rods ( for black, white and shades of gray vision ). The bass eyes can receive five
times more light than the human eye. This allows them to distinguish shapes, sizes,
movements and color patterns the human eye cant! Bass do this under varying water
clarity and light conditions! Bass do not have eyelids so they can not blink or close
their eyes. What they do have is a black pigment ( not present in the human eye ) that
shades the photosensitive cells of the retina, which allows them to see well in extremely
bright conditions with no discomfort. This dispels the conception that bright lights hurt
the bass eyes!!! Even though they are supposed to have a fixed focus pupil,
bass have the ability to adjust their eyes to varying light conditions. The lens of the
eye moves back and forth to change the roundness of the eyeball itself. By doing so this
influences the amount of light entering the eye. Even though bass can spend a great deal
of time in the sun without discomfort, they will often use a shady spot for ambushing
prey. In fact, a feeding bass will do just that ! The visual acuity of the bass increases
approximately three fold when looking into bright areas from shady ones. Forage
moving about in the bright sunlight have trouble seeing bass in the shade, but the reverse
is not true. The smart and crafty bass positions itself to take advantage of its
superior vision. The bass has an extremely wide field of vision, a full 180 degrees for
each eye. This allows them binocular vision in front and slightly upwards due to the
overlap of the 180 degrees of sight with each eye. The bass is most effective at striking
its prey and lures in their binocular zone. The only blind areas for the bass exist from
his side fins back and under its belly. Research has shown that a bass vision
increases with age. A bass eyes will continue to grow throughout its life regardless
of its body growth. This could very well be another reason that lunker size bass are so
difficult to fool with artificial baits. The bass eyes are equipped for both
day and night time vision. During the daylight, the cones in the retina move forward and
the rods move backwards. At night the movement is reversed and they use their rods for
black and white vision. Periods when light level changes, such as dusk and dawn are
interesting times. A humans eyes adjust to the change quite a bit quicker than those of a
bass. It only takes about 30 minutes for most humans eyes to adjust to these changes. The
bass is far less fortunate. At dusk the rods in the bass eye move forward in the
retina for after dark vision. It takes almost two hours for the bass eyes to
fully adjust for night vision. At about two hours before first light, the change
back to daylight mode begins. Contrary to what most during anglers have been taught,
fishing maybe extremely slow during the first two hours of dark and the last two hours
prior to daylight. Color vision is very important to the life of a bass. Most bass
rely on their color vision for feeding, self defense and for spawning signals. Tests have
shown that bass have excellent color vision and can easily distinguish between closely
related colors. According to research studies, they can also tell the difference between
different shades of the same color.
In closing this article, I hope I have shed some light on the bass sense of sight.
Hopefully I have dispelled some previous myths. This information should help all to
better understand how the bass sight works. Make sure you keep checking back for
other articles written by myself. This is the first in a series of articles on the
bass senses. Always remember to take a kid fishing. Today's children are our future.
Good luck, Leo
Watson, Pro Staff - Contact me with your questions or comments at leo.watson@bassonhook.com Leo's Articles
are also published at http://www.bassonhook.com