The long wait.
Somewhere beneath your feet a live bait is traveling straight down 40, 50, even 150 feet. Finally the slip float stands up. And immediately disappears. Another basin dweller feels the hook slam home and begins to sound for bottom.
In recent years, jigging vertically with soft-plastic tubes has been the most popular method for taking summer and fall lakers from inland lakes around the Great Lakes region. Not that the traditional arsenal of jigging spoons and bucktail jigs no longer works. Quite the contrary. But tubes are more subtle, can be fished on lighter line with spinning gear, and appeal to both highly active, aggressive fish and wary, heavily pressured fish.
Famous Wisconsin guide Greg Bohn recently found a better method for pressured trout that respond to nothing else: Presenting live chubs and suckers on slip-bobber rigs—a method actually suggested by a client.
“After several hours of jerking spoons for lake trout and one whitefish, my client Marty Smith said let’s try slip bobbering for these lakers,” Bohn said.
Having written definitive works on the subject (Slip Bobbering and Night Slip Bobbering), Bohn said, “why not— nothing else was working, though we were marking several lake trout at 65 feet over a tiny rock hump. We tipped the slip bobber with a 5-inch black chub and before it reached the deep bar, a big laker shot up to hit the bait. I watched it happen on my Lowrance Gen 2. That bobber disappeared unlike any strike I ever had before. Within seconds, we had our first slip-bobber lake trout on the line.”
Inland Lake Similarities
“This is not Canada or the Great Lakes,” Bohn said. “We’re accustomed to fishing for lake trout on many small, local, inland lakes in Wisconsin. Some of these lakes are only several hundred to possibly a few thousand acres, some bigger. In either case, inland lakes with lake-trout populations have several key ingredients, like deep main-lake basins of at least 45 to 60 feet with one or more deeper holes of 65 to 125 feet or more. Lakers thrive in cold, extremely clear water.”
Water temperatures over 60°F can be fatal if lakers can’t escape to deeper, colder, well-oxygenated water. They may rise into 60°F water to feed, but won’t stay long. Having oxygen below the thermocline is essential—generally a characteristic of deep, geologically young, oligotrophic lakes. One common feature in these lakes is rocky structure in the deep basin. Lake trout broadcast spawn over boulder fields in the fall, typically in depths of 15 to 25 feet, so rocks aren’t just preferred habitat, but a critical component of successful recruitment.
“No deep water, no lake trout,” Bohn says.
“The best lakes have a mean depth of over 30 feet with lots of boulders, rock, and gravel. Deep mud basins are common, too. The forage base needs one or more deep- or open-water species like ciscoes, whitefish, smelt, rainbow smelt, bloater chubs, or sculpin.” Amazingly, sculpins are among the deepest ranging of these species, persisting to the benthic fringe of the areas lakers use, according to USGS biologists using bathyspheres to study lakers on the Great Lakes. Sculpins, like gobies, have no swim bladders and can’t suspend—one reason the deepest lakers often stick tight to structure.
“Boulders always present a key locational factor—spring, summer and fall,” Bohn said. “Lake trout are accustomed to feeding around boulders, which forage species use for cover. But not all boulders are equal. Use by lake trout depends on location and depth. Shallow boulders see more use in fall, winter, and spring. During summer, lake trout know the whereabouts of every deep boulder, hump, or rocky piece of structure, and make regular visits. When lakers suspend, it generally takes place in that part of the water column above deep, rocky structure and adjacent mud flats.”
Isolated structure can be a big-trout magnet in lakes with a lot of fishing pressure.
Small, barely noticeable spots in 60 feet of water or more that escape the map and chart makers are gold nuggets for a slip-bobber expert like Bohn. “Deep mid lake humps need not be large in size or very noticeable to become an attraction,” Bohn said.
“A lot of fishermen skip the extensive mud flats, too. We never mark fish out there until a live bait pulls them off bottom. But we often find the biggest lake trout schools on small, overlooked locations on these inland lakes.”
Visible fish—the ones showing up off bottom on sonar—are active biters.
But when trout can’t be found on classic or isolated structure. Bohn knows where to look next. “When I find a long point extending down to 80 feet and I see no activity, I know they’re in the mud,” he said. “These inland lakers are different. Spooky. Pressure will chase them off classic structure. In 75 feet of water, trout will move away from your boat. They are so untouched. I really like fishing the deep mud flats because lakers love silt and muck. They love laying in it and above it, and I think it’s the pressure that drives that dynamic. Don’t be disappointed if you don’t mark any deep arches. Often lake trout are tight on the hard bottom or in the soft mud. Mud fish can be coaxed into taking a live chub drifting by.
If your sonar can zoom in on the bottom, go to a magnification of 3 to 4 times to spot deep fish. I use the auto range or standard view for suspended fish because you miss fish high in the water column if you keep zeroing in on the bottom.”
Greg Bohn, one of Wisconsin's most famous walleye guides, and author of several books on the art of slip-bobber fishing, recently discovered nothing works better for spooky, pressured, inland lake trout than a live minnow struggling at a precise, exact depth under a float.
Bohn’s angling philosophy, whether fishing for walleyes, lakers, or crappies, demands separating the good spots from the very best spots by staying mobile and aware. “It’s the old majority vs. minority game,” he said. “Find them first. Lakers use sections of the lake rather than the entire lake. Keep scanning the bottom searching for active trout and possible fishing areas. Cold water temperatures and baitfish schools are important to location. If you find lakers suspended over deep humps, that’s the pattern you’ll see repeated all over the lake. So, once you find lakers, scan your charts and waypoints for similar spots. Spend some time scanning every likely spot, and spend some more time looking for those isolated spots, before setting up for a slip-bobber assault. ”
Sifting the Water
In over 35 years of reporting on the outdoors, I’ve never encountered anyone who fished slip bobbers deeper than about 30 feet—and that was for walleyes on the mud flats of Mille Lacs in Minnesota. Fishing 50 feet or deeper with slip-float rigs? Relatively unheard of on fresh water. In retrospect, Bohn says he may not have thought of it first, but it makes perfect sense.
“Even experienced lake trout fisherman often shake their heads in disbelief after a day chasing inland lake trout and trying to get them to bite,” Bohn said.
“Few anglers reach inland lakers with the right enticement in these deep-water habitats. Fewer yet catch lakers with consistency. Inland lake trout are extremely aware of even the slightest angling pressure. They are extremely smart, wary, and for the most part live out their lives undetected by anglers. Anchoring too close to a school or even losing a fish after a long fight can spook inland lakers.” 
The smaller the environment, the spookier the fish. “Yet you’ll be amazed at what a slip-bobber rig can do,” Bohn said. “Slip bobbers can be fished at any depth. That’s what makes them so effective for deep-water fishing. Slip floats can present a live chub 150 feet down and it’s easily done, though you rarely need to fish that deep. When fish are suspended at 55 feet, there are times when they won’t hit it unless it’s right in their lap at that depth. That’s the advantage of slip-bobber fishing.”
Bohn uses Thill Pro Series Slip Floats that feature a brass-grommet insert in the tip of the stem. The insert allows line to reliably free-fall through the float with less friction. The largest size (XXL) is a full inch in diameter and holds up roughly 1-ounce of weight—plenty to get down deep with 10-pound Stren Magnathin. “I use up to 1-ounce Water Gremlin Rubbercor sinkers,” Bohn said. “Sometimes a 1/4-ouncer will do, when they’re shallow. There are bigger slip floats you can use and the advantage is getting down quicker. The smells are the same thing I use for walleyes with Tru-Turn size #1 or #2 hooks in gold or red. I always have blades on the rig, size #2 willow-leaf blades in hammered nickel with a clevis and a size #6 red glass bead. Red is a really good color. Always have good luck with that. Sucker minnows work well, too, and they’re very hardy like the chubs. Either species can survive being dumped into the benthic depths and retrieved.”
Tru-Turn Hooks, Thill Pro-Series Floats, SPRO Power Swivels, and Water Gremlin Rubbercor Sinkers. (And some bait. And a couple float stops. Maybe some heart medication…)
“Regular 9-foot slip-bobber rods for we make for walleyes work fine,” Bohn said. “I use snelled 10-pound mono leaders 24 to 30 inches long for both walleyes and lake trout. The weight is right above the swivel, so it’s 32 to 35 inches between weight and bait and a pretty handsome rig. They can see it from a long distance. They hit much bigger baits than 5-inch chubs and suckers. I use 10-pound Magnathinfor a main line because that’s the line on my slip float rods for walleyes,” Bohn said. “I don’t change much from my walleye rods, which proves your don’t need special equipment.” But don’t be afraid to try a braided line, like Berkley FireLine, which is thinner than monofilament, creating less resistance. Braided lines also have about twice the advertised breaking strength, and very little stretch—which could be a critical factor when setting hooks at 80 feet or more.
“Lakers shoot up so fast,” Bohn said. “Stretch can be a good thing, too. They shoot up like rockets to take baits, and the fight is amazing. The bobber disappears so deep, so fast—even in clear water, you just suddenly can’t see it anymore. You don’t have to wait. Just set the hook. If you use drag, you better have it set carefully before you drop a bait down there. They can scream out line like no other fish in these inland lakes. You don’t get many strikes, but when you do, it’s always an exciting experience. The lakes are so clear, you can see the fish fighting down 15 feet or deeper. ”
Bohn often presents the slip-float on a rod placed in a holder while jigging with a second rod. “We use hair jigs, spoons, and big Kalin’s Grubs on regular 7-foot, 2-inch walleye rods, too,” he said, “but the slip bobber rig is so precise at putting live bait at exact depths, it’s hanging right in their face, struggling against the hook and you can’t achieve that with other lures. I was really surprised how effective it is. Now I use it every time we go out for lake trout. You get only 3 to 5 strikes a day, but that’s amazing for inland lakers sometimes. Calm days are the way this thing works. The liveliness of the live bait is the key. Just let it work under a fixed float on a flat day. Sunny flat days are best.”
Because inland lakers can be spooky even down deep, Bohn throws markers above a rock bar or deep tip of a point so he can keep his distance. “We often throw a marker, anchor well off the bar and cast quite a distance,” he said. “You have to cast well past the spot as the sinking rig drags the float back toward you. It takes a long time to get down, even with 1-ounce sinkers, but you have to be ready, They’ll come up 40 feet to hit it and you can’t see them rising when casting. The neat thing about the slip bobber is you’re only casting about 4 feet of line. Long casts are easy. It’s like deep-water walleye fishing.”
Unlike most fish, a hooked laker is able to dump air as it rises, relieving pressure on the swim bladder so it can be safely released with no threat of barotrauma if you take your time bringing it up.
With big fish, that’s not a problem.
The size of the air bubble is an indicator that can raise the hair on your neck. And when you see several bubbles, some excited, curious followers are coming up behind your fish. In clear water, you can see them circling below the boat.
“Inland lakers are totally different animals,” Bohn said. “What a neat thing to be able to do—the clarity, the depth, the cold water, and the way they fight. A laker on light gear is a tough, tough animal. They average close to 30 inches around here. A nice one is 35 inches. A really nice one is 40 inches.”
Well worth the wait.
- written by Matt Straw