Two of the keys to success when fishing for largemouth bass in any lake, are:
A. Determining what seasonal pattern you will be faced with. B. The location of the highest percentage spots to fish during that seasonal pattern.
In the upper Midwest, on both natural lakes and reservoirs, the largemouth bass will begin their migration toward shallow water almost immediately after ice out. The purpose of this migration is twofold - feeding and eventually spawning. If you can locate the best shallow areas, you will be able to follow the fish throughout the spring, and into post-spawn.
My usual research routine starts in the off-season. I like to purchase no less than two different brands of lake maps for each body of water on my tournament schedule. You will find that the detail of maps vary from manufacturer to manufacturer depending on their mapping source, but most information is good information and I will take all I can get! Typically any tournament I have from ice out through the end of May, I can classify as pre-spawn.
I will carefully study these maps, paying particular attention to bays that have shallow flats (under 8’ of water) in the northern section of the lake. Ideally, bays with an expansive flat in the northwest portion of the lake will captivate my interest. These bays will see more sunlight and are at least somewhat protected from prevailing winds. I will highlight as many of these flats as possible on my maps, and will check most of them when pre-fishing.
Some of the characteristics that will make a flat special, include:
Defined point/points at the mouth of the bay. Secondary points within the bay. A creek channel. Deep drop-offs or ledges outside the flat. Inside turns. Submergent or emergent vegetation. Stumps or brush-piles. Rocks or riprap.
When actually on the lake, a surface temperature gauge is a must for determining not a particular temperature, but some of the warmest water you can find. Often you will find the main lake more than 5 degrees colder than a bay. When I start checking the bays I had highlighted on the maps during pre-work, I will start fishing in the warmest areas first and these will most often be dark bottom bays.
Nine times out of ten I will circle the flat within the bay to see the actual layout in comparison to the maps. Then I will zigzag through the flat with the trolling motor on high and throw a swim jig or a spinner-bait. I am doing two things in this process - trying to get bit, and scanning the water looking for baitfish, pan fish and bass.
If I start getting hits or catching fish on the flat, I will begin to refine the pattern. Is the activity I am experiencing coming off of stumps, brush piles, new weed growth or perhaps rocks? When I determine if there is some specific cover or structure on the flat that is producing fish, I slow down and work every similar spot on the flat thoroughly.
If I cannot get the fish to bite, and the flat is void of any visible baitfish or game fish, I will not abandon the area. It is very possible that by late morning or early afternoon this flat could be loaded with fish due to warming water throughout the day. To quantify the productivity of an area you need to move deeper by working your way out of the bay, fishing the secondary points, creek channels, inside turns, ledges and drop-offs (indicated in the map where several contour lines get very close to each other or touch), and then finally the main lake points at the mouth of the bay. A largemouth bass will use all of these types of structure as “stopping points” on their path to and from the flat.
Baits that work well for me for these pre-spawn deeper presentations, are weighted suspending jerk baits, a Super K football jig with a twin tail grub, a 3/4 or 1 ounce Super K Plunking jig, Carolina rigs, shakey head worms, a drop-shot rigs, or spider-grubs.
Fishing in this manner allows me to find where the fish are in terms of their migration to the flat. When you begin catching fish, be sure to document, at least mentally, the time of day, weather condition and surface temperature because this may be replicated in similar areas of the lake.
The important part of spring and pre-spawn fishing is your adaptability. If you are catching fish and they turn off, it is time to adapt to the situation. If you are catching fish on the flat and the bite slows, think about your surroundings. Did cloud cover take the heat of the sun out of the equation? Did the wind pick up or shift and push cold main lake water into the flat? If that is the case, these fish are not necessarily negative, but may have moved closer to the deeper water or structure that they use on their migration highways within the bay.
Conversely, if you are catching fish in the deeper structure areas and they turn off, it is just as likely that the flat is warming enough that it has become inviting to the whole food chain, bass included, and you need to follow those fish shallower.
A lot is said about “fishing the moment”. Never is this phrase more obvious as in the springtime during the pre-spawn on our northern lakes. Your success hinges on your versatility in fishing techniques and your ability to think through the situations that may arise.
If you follow the premise outlined above, I am 100% confident you WILL find pre-spawn fish. If you learn to adapt to the movement and mood of these fish, you can catch them all day long!