The Sense of Sight

All freshwater sportfish can see. How a fish uses its eyes depends on physiological and environmental factors. It only stands to reason that fish in clear water feed more by sight than those in water bodies where visibility is poor. A bass in a clear lake may be able to see a lure 15 feet away. The same fish in a lake with muddy water will rely primarily on other senses to locate and capture prey.

To various degrees all fish are sensitive to light. Lake trout studies show the development of cataracts in fish exposed to strong sunlight for prolonged periods of time. The walleye, named for its large, extremely light-sensitive eyes, has excellent vision under low-light conditions but can be inactive and therefore hard to catch under bright, clear, daylight skies. When water is clear, walleye fishermen crave overcast days or a steady wind to put a chop on the water and cut down light penetration.

The members of the family Esocidae, such as northern pike and muskellunge, are specialized sight predators. Their eyes are set well forward on top of the head. This gives them a narrow field of binocular vision. These fish can strike moving objects with great accuracy even when they are travelling at very high speeds. The position of the eyes indicates that pike and muskie see objects above them better than those on the same plane. This characteristic allows the fish to easily see the silhouette of prey against the lighter background of the surface.

In comparison, the large and smallmouth bass have eyes situated well apart on the sides of the head. This enables the fish to see to some degree in all directions: above, below, behind, forward, and sideways. Wide-angle vision, rather than highspeed accuracy, is the key to the bass's forage success.

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