Seasonal Keys To Catching Walleyes On Flats

The most common and prolific flats pattern in reservoirs of all types takes place in early spring. Prespawn and Postspawn walleyes congregate on flats immediately adjacent to spawning tributaries, in this case, in the back end of a major creek arm. Some walleyes spawn on riprap shorelines near dams, collecting on shallow, shoreline-oriented flats nearby. In creek arms, walleyes follow a consistent progression, moving gradually toward the main lake and gathering on large fertile flats along the way. By early summer, most walleyes are on main-lake points at the mouths of these creek arms. Depending on water levels, weather, and dominant forage species, active walleyes may feed anywhere from 5 feet to 25 feet during early summer. Some move progressively deeper as they spread out into the reservoir. Deep flats with humps and submerged islands become the most dependable patterns in late summer. By late fall, many walleyes are back on primary points leading into creek arms, but tend to use vertical structure close to the main river channel.

These tactics, developed on the Great Lakes, continue to work wonders there. Downriggers plunged only 10 or 15 feet under the surface with long leads to diving lures, still predominantly used in the Great Lakes, are even more efficient for precise depth control.

Fall and Winter

As the days shorten in September, walleyes start grouping in predictable locations. Classic hard-bottom structure on the main lake where breaks slope quickly from mid-depths into deep water are key spots, including flats atop main-lake bars and humps, and especially flats in the main basin adjacent to classic structural elements.

In early fall, some walleyes continue to cruise weedlines on shallow flats. In fact, this pattern becomes more productive in some lakes during September and continues into October. In prairie lakes and other shallow bodies of water, this pattern continues practically year ‘round. The general trend, however, is for walleyes to gradually concentrate in deeper main-lake areas.

By late fall, the most reliable pattern in meso lakes is the “transition bite” that takes place on the edge of deep flats. Walleyes show a consistent preference for edges where soft and hard bottoms come together at the deep base of main-lake points and bars. This pattern holds all winter, though the early-winter bite often shifts from the base of these structures to shallow pivot points on the shallow lips of these areas.

Look for the largest structures extending into the main basin of the lake and for transitions somewhere near the base of the slopes from these structures, where they meet the basin flat, or slightly shallower. A hard reading on sonar (a thick bottom line) butting against a thinner reading is the target area. This transition line can be at different depths on different structures. In fact, it’s often found at different depths surrounding the same piece of structure, moving gradually up and down from, say, 40 feet to 35 feet or so. In mesotrophic lakes, bottom transitions usually occur somewhere between 20 feet and 60 feet deep, with 25 to 40 feet being the most common range. The transition isn’t wide, usually about 2 feet across, and walleyes hold tight to it.

In the Great Lakes, flats adjacent to major spawning tributaries attract walleyes in fall. By October, night fishing near jetties, rockpiles, and pier walls on huge sand flats really heats up. Of all the bites on flats for walleyes, this is the most recognizable and easiest to identify. In addition, it’s the most consistent pattern for fish over 8 pounds.

In winter, many walleyes in large meso lakes and reservoirs tend to move during periods of activity to main-basin flats and flats on top of main-lake humps and bars. As winter ebbs, walleyes again begin concentrating closer to those shallow flats adjacent to spawning habitat where this discussion began.

Presentation—Early in fall, shallow and mid-depth flats on the main body of the lake still harbor walleyes. The focal point is the weedline. It’s not the primary pattern in meso lakes, but it is overlooked, and it can be the main pattern in shallow eutrophic bodies of water, such as prairie lakes. Ripping crankbaits like a Normark Shad Rap, a PRADCO Wally Bomber, or a Storm Rattlin’ Thin Fin along deep weededges locates fish quickly and often continues to catch fish all day.

Sometimes, especially on windswept water on cloudy days, walleyes cruise right over the weed tops. Shallower divers like the Mann’s Stretch 1 Minus or the Rattlin’ Thin Fin work well for covering that part of the water column. Some walleyes are always present at the base of the weeds, where a deep diver is required to dig them out.