How sensitive is a fish? - Sight
Sight - most important in many species, especially shallow water hunters (bass). The modification in eyes of nocturnal feeders is a mirror-like membrane behind the retina used to pick up and reflect stray light back into the eye for shape definition in dim conditions. This gives a ruby red glow in the eyes of barramundi and jewfish, which are superb night operators.
A fish's field of vision is wide, they can even see out of the water, because of refraction, the rule is: "if you can see, the fish they can see you". So, don't alarm fish with clumsy rigs, thick lines, big, exposed hooks and arm waving near the water's edge, wearing of bright clothes.
How sensitive is a fish? - Hearing