Algae blooms are a fact of life this time of year on lakes across the Walleye Belt. Though dreaded by many anglers, they can create opportunities for some of the season’s finest fishing for all sizes of walleyes. Best of all, you don’t need to be a night owl or brave foul weather to pull walleyes from beneath the green curtain. You just need sunscreen and shades, because some of the fastest action occurs on calm seas under scorching sunny skies.
Veteran North Woods guide Jeff Sundin has been chasing summer walleyes across central and northern Minnesota for three decades. His fishing grounds include rivers and lakes of all shapes, sizes, and types, and if a pattern exists for putting hot weather walleyes in the boat, he’s tried it. To the surprise of many anglers, one of his favorite setups is a full-blown bloom on a walleye-rich, fertile fishery.
“It looks disgusting when the water’s so green that you leave a hole on the surface when you drop your bait through it,” he says. “A lot of people take one look at these conditions and say, ‘Nope, I’m not doing this.’ But if you fish the right spots with the right tactics, algae blooms can produce some of the summer’s most consistent and enjoyable walleye fishing.”
I can’t argue with him on any of this. Years ago, while editing In-Fisherman’s Walleye In-Sider magazine and covering the company’s Professional Walleye Trail, I tailored some of the PWT pros’ algae bloom tactics to my home waters a short cast north of Minneapolis and struck walleye gold. Even though these lakes were within an hour’s drive of hundreds of thousands of anglers and offered ample public access, I had the spots—and the fish—all to myself. As a bonus, there wasn’t a water-skier or jet ski in sight.
Like most of my fishing strategies, the plan was simple. Find a promising rockpile, hump, or point where walleyes would likely feed at twilight in clear-water conditions and fish it during the midday hours when the lake greened up. Nothing fancy, either. I hovered my boat over the spot, jig-and-minnow in the sonar cone, and watched the fish react to various jigging cadences. Most days, this approach yielded a mix of walleyes and crappies.
As with most presentations and patterns, Sundin elevates the algae game to an art form. He begins by noting the link between blooms and good fishing likely extends beyond just the conditions created during the bloom. “The lakes we fish that have the heaviest blooms typically have expansive shallow flats and are warmer, more fertile, and more productive than deeper, clear lakes,” he explains. “So even if you didn’t have a bloom going on, these are better fishing lakes anyway. The bloom just accentuates it by concentrating aggressive fish in predictable locations.”
Finding those hotspots is the key to success when you’re faced with a sea of pea soup. Although Sundin keeps the search simple, he avoids classic summer structure, and ventures instead into areas where few fishermen tread.
When a lake’s in full bloom, he focuses on weedy shallows shunned by most summertime walleye anglers. “You’d think shallow water would be too warm and the fish would go deep,” he says. “But a couple of factors combine to make the shallows attractive to walleyes. First, the depletion of dissolved oxygen below the thermocline limits how deep walleyes can go. So, on many lakes, the deep edges that held fish from late May into early July are now out of play.”
Second, and equally important, he says, shallow weedgrowth offers a sheltering environment rich in oxygen and flush with forage ranging from large aquatic insects to crustaceans, minnows, and bite-sized panfish. “Throw in the added shade from an algae bloom and shallow weeds are hard for walleyes to resist,” he says.
Productive depths vary by lake, of course. “I spend a lot of time fishing 5 to 6 feet,” Sundin says. “But walleyes can slide into 3 or 4 feet of water and still be more comfortable than they would be in clearer, deeper water.”
While you’d think finding submerged weedbeds in such low-vis conditions would be challenging, he says just the opposite is true. “It’s an interesting phenomenon. The weedflats are shallow and the tops of the weeds practically break the surface,. You can see insects and small baitfish dimpling the surface. Hovering right over the top of the weeds, they’re a dead giveaway for where to fish.
“It helps that you’re typically doing this in flat-calm conditions, which, combined with hot, sunny weather, tend to produce the heaviest blooms and congregate the most fish in the shallow weeds you’re trying to find,” he adds. “Under these conditions, you can look around the lake when it’s calm and see the areas of activity. We could talk about using the latest in side-imaging sonar to figure it out, but you can find the best spots with the fishfinders on the front of your face.”
All vegetation isn’t created equal in the eyes of walleyes or savvy anglers, and Sundin perennially steers for specific species of vegetation. “You may find walleyes in any decent patch of green weeds,” he says. “But the best, at least in my area, are patches of cabbage growing on shallow flats. Walleyes swim right past coontail and other weeds to get to them. That being said, if your lake doesn’t have cabbage, they use other vegetation types as long as they provide cover and produce oxygen. Don’t shy away from thick vegetation, either. Sometimes the best beds are so dense you can only fish the outskirts of them.”
Location can also play a role in a weedbed’s promise. “Another trick to making this program work best is to focus on patches of vegetation that grow closest to a steep break near the shoreline,” he says. “So if you have a big wide flat with weeds all over, look to the corners of the bed close to a shoreline break—as opposed to the center of the greenery. I’m speculating as to what the walleyes think, but I believe they like being able to hold in the weeds one minute and dart out into deeper water the next.”
Once Sundin settles on a likely area, he breaks out standard jigging tackle. “The same pole you’d use for virtually any jigging application is fine,” he says. “I like a 6-foot 3-inch to 6-foot 9-inch light to medium-light spinning rod with a fast tip, that handles line weights from 4 to 8 pounds. I typically use 6-pound mono on all my rods. Simple and easy to fish, yet effective.”
Jigs are his weapon of choice, and he isn’t shy about tying on leadheads with enough heft to take the bait straight to bottom in heavy cover. “Too light a jig is a deal-breaker,” he says. “Even in five feet of water, I use at least an 1/8-ounce head and sometimes 1/4-ounce is even better. The goal is to drop the jig straight down into small openings in clusters of cabbage or coontail, briefly hold it in place, then pull it straight up and out. If the jig starts moving horizontally at any point in this process, you might as well be dragging it across your lawn, because it’ll get stuck on every blade of grass.”
To reduce snags yet provide solid hookups, he favors relatively short and stout jigs like the Live Bait Jig he designed for Lindy Fishing Tackle. “The compact jig helps prevent hangups,” he says. “It also allows you to rig minnow so the hook is coming out the top of the skull and the minnow’s mouth is pushed tight against the jighead. There’s no extra space between the bait and the jighead for weeds to get wrapped up on, like there is with long-shank jigs.”
Sundin’s jig color palette covers the spectrum. “I experiment with bright patterns like chartreuse yellow, but also go to the opposite extreme with black. I probably tie on black more than anything else,” he says. “Keep in mind, the water may be green at the surface, but you don’t have to get down very far before it clears up, so the fish still have fairly good visibility.”
While it’s tempting to dance a jig, Sundin is adamant about no animation. “No jig action is key,” he says. “Lift the jig just off bottom, hold it still for 15 to 30 seconds, then lift it up and pick the next pocket.” He also cautions against running, gunning, and flights of wild fancasting. “The object is to slowly pick your way through these little patches of vegetation,” he says. “Done correctly, it’s like bass fishing—flipping and pitching into holes and open pockets in the canopy. Although you’re not casting, you’re literally dropping the jig from the end of the rod tip at boatside.”
Strikes are hard to miss. “Walleyes hit and you smack them right away,” Sundin says. “There’s a very low level of finesse involved in this technique. Most people enjoy it once they get the hang of it. There’s plenty of action, because bonus crappies, perch, and pike are common catches along with walleyes of all sizes.”
Sundin’s bloom jigging isn’t exactly a laid-back affair. “You’re so focused on getting your jig down through the weed and pinpointing it in one spot, it gets intense,” he says. “You’re not sitting back in a chair, relaxing. After a while the back of your neck gets tight and your eyes bug out, but it’s worth it.”
As a bonus, anglers who dial in a happening weed bite in one spot can often enjoy similar success elsewhere on the lake. “It’s a repeatable pattern,” he says. “A school of walleyes don’t go to one spot like they might gather on a big rockpile. They spread out in little groups, so you’re more likely to find three or four walleyes per small weed patch.”
Solid midday action is common during algae blooms. “It’s possible to be too early for the weed bite,” Sundin says. “In the morning, when the sun is low and the algae isn’t in full bloom, walleyes are scattered. You need calm, hot, sunny conditions and algae development to concentrate the fish in the weeds.”
On the flip side, a strong summer wind can shut down the algae pattern in a hurry. “This isn’t a windy day deal,” he says. “A strong wind that stirs things up definitely moves the fish out of shallow vegetation. If you’re in the middle of a day and the weed pattern has been working, then the wind works up a nice chop, it’s best to put your jigs away and try something else.”
Sundin’s Plan B when a wind whips up is trolling spinner rigs. “Windy conditions encourage walleyes to move out to the edges of these same weedflats and feed,” he explains. “A simple setup like a 1/8- or 3/16-ounce bullet sinker and Little Joe spinner rig with half a nightcrawler puts plenty of fish in the boat. The cheapest, ugliest fatheads you can find also work well, and pick up more of a mixed bag of fish species, but ‘crawlers catch more walleyes on average.”
He trolls weededges at 1.1 to 1.2 mph, slipping the rig along the tops of the vegetation. “You don’t want to get stuck down in the grass,” he says. “Choose sinker weight to keep you running at the weed tops.”
In-Fisherman friend and decorated tournament pro Keith Kavajecz doesn’t turn his back on a good algae bloom, either. “The walleyes’ metabolism is firing on all cylinders and the fish feed aggressively,” he says. “Don’t let a little bloom keep you off the water.”
Two of his top tips for tackling algae involve timing and colors. “The fish tend to bite better throughout the day, but you often find the evening bite isn’t as good—either because it’s too dark or the walleyes have been feeding all day,” he says.
“As for lure colors, remember light penetration is reduced. A lot of the same tactics that work in clear conditions also work during a bloom, but you might need to switch to cloudy-day colors like glows, whites, and bright chartreuses, versus the holographics and chromes that produce well in clear water with no algae. I’ve seen this happen many times while fishing a Shiver Minnow in August, but it holds true with other presentations, too.”
Besides shivering, trolling is one of his go-to bloom tactics. “Crankbaits and spinners have universal appeal,” he says. “However, a few adjustments are in order. To slow the rate at which algae slides down the line and fouls your presentation, pinch a split shot the size of an 1/8-ounce jig in front of the lure or spinner. A snapweight positioned 50 feet ahead of the lure also excels at this—but it also affects the dive curve, especially at slower speeds.”
Kavajecz notes that a thin superline like Berkley FireLine slices through blooms without accumulating much algae. “Thanks to the lack of stretch, it also lets you know when algae or moss from the lake bottom has fouled your lure,” he adds.
He does have his limits when it comes to summer blooms. “A little garden-variety surface algae is fine, but when the goop gets so thick it turns blue and clumpy, the fish don’t like to be around it—and neither do I,” he says.
Like Kavajecz and Sundin, fellow walleye warrior Jason Mitchell is also a fan of fishing moderate blooms. “We get a lot of them in the fertile lakes in the Dakotas,” he says. “They scare some people away, but produce tremendous walleye fishing. The fish bite all day and don’t spook from your boat, even in shallow water.”
Mitchell also takes steps to keep his lures clean. “A 1½-ounce bottom bouncer works wonders as an algae stopper,” he says. “I blaze through prime areas at 2 to 2.5 mph trolling spinner rigs with deep-cupped #4 and #5 Colorado blades. You don’t need livebait going that fast. Soft plastic trailers like a Gulp! Crawler or various paddletails are awesome.”
As for location, Mitchell plays the shallow game—but he also goes deep. “Weedlines in 4 to 8 feet of water are good, but top shallow spots include where a weedline and top of a sharp rock breakline meet,” he says. “If walleyes aren’t up shallow, look to main-lake structure in 30 to 50 feet of water, sweetened by boulders or smaller rocks. Here, slipbobbering livebait or vertically fishing jigs and softbaits or hard lures is your best bet unless the structure is large enough to allow trolling runs.”
*Dan Johnson, Isanti, Minnesota, is a frequent contributor to In-Fisherman publications and director of All Creation Outdoor Media. Guide contact: Jeff Sundin, 218/259-2263.