The common name, "walleye", comes from the fact that their eyes, like those of cats, reflect light. This is the result of a light-gathering layer in the eyes called the tapetum lucidum which allows the fish to see well in low-light conditions. In fact, many anglers look for walleyes at night since this is when most major feeding patterns occur. Their eyes also allow them to see well in turbid waters (stained or rough, breaking waters) which gives them an advantage over their prey. Thus, walleye anglers will commonly look for days and locations where there is a good "walleye chop" (i.e. rough water). This excellent vision also allows the fish to populate the deeper regions in a lake and can often be found in deeper water.  - Wikepedia: http://en.wikipedia.org/wiki/Walleye