Each zone on the map represents the approximate date (to the nearest week) when walleyes begin spawning. Actual dates in your immediate area may vary due to local water temperatures and weather conditions. Note that the dates listed apply to large, public waters, and remember that fish will spawn earlier in smaller or shallower water bodies.
Spawning activity in rivers is highly dependent on the weather upstream, and the spawn may occur earlier or later than in nearby lakes. Expect walleyes to spawn earlier in rivers with high input of water from springs. For example, the spawn in the Current River in southeast Missouri usually happens two to three weeks earlier than in nearby rivers and reservoirs lacking substantial spring flows.
Walleye fisheries have been established throughout much of the west, and elevation will strongly affect the spawn. In Wyoming, for example, walleyes spawn in early April in Glendo Lake, at an elevation of 4,600 feet, in late April in nearby Alcova Lake, elevation 5,500 feet, and as late as early May in Seminoe Lake, elevation 6,300 feet. Obviously many factors can affect the time of the spawn, but the spawn timing for walleyes is all about water temperature. When it hits 45 oF you better be ready to go because the fish are. In northern regions, the waters can warm to 45 oF within one to two weeks after ice out.
Male walleyes begin moving to the spawning shores or shoals about one week before the females. If you are catching a lot of small fish, especially fish that are spewing milt, come back in three to five days when the big females show up.