Give Yourself an Edge by Captain Mike Schoonveld

Give Yourself an Edge by Captain Mike Schoonveld

I was a hunter first and a fisherman only when there were no hunting seasons open when I was young. I was mostly a self-taught hunter and there’s no lesson plan for the “school of hard knocks.” Only with time and experience did I learned the best places go as I traipsed over field and forest in quest of whatever was my quarry that day. I learned the lessons, I just didn’t know what to call them. 

A few years later, as I was studying to become a wildlife biologist, some of the lessons I learned at Purdue reinforced what I’d already found true in the field.

One of those is the concept of “edge.”

Edge is the place where two different habitat types come together. Where a meadow transitions to a woodland is an edge. Where a marsh or lake transitions to an upland area is an edge. 

There are some species of game and other wildlife totally dependent on one habitat type. They are only found in dense woodlands or they live out their lives never leaving a marsh. There are many, many other species fitting the bill as edge species. They get a part of their habitat needs, say nesting and resting cover from a woodland, but they get their feeding and breeding habitat in grasslands or croplands. 

The pheasants, quail, rabbits and fox squirrels I pursued as a young man were edge species and my on-the-hunt training taught me I had greater success along the edges than putting on miles and miles through the center of large forested areas or wandering through huge tracts of monotypic uplands. 

Interesting stuff if you are a hunter, but this is Great Lakes Angler, not Great Lakes Hunter magazine.

How does this relate to catching more fish from the Great Lakes?

Years ago I participated in a fishing derby in Thunder Bay, Ontario called the Lake Superior Trout Hunt. It was a catchy name, made so because most people don’t directly associate fishing with hunting. With fishing, the fish are out there, the trick is to get them to bite the lure or bait. With hunting, the game is out there, the trick is to find them and get in position for an accurate shot. 

That’s two different concepts, isn’t it?

Maybe it’s not so different, especially when it comes to Great Lakes fishing. 

The Great Lakes are huge and there are millions of trout, salmon, walleye and other game fish in each lake. But there’s much, much more water. Luckily, the fish are not distributed evenly across the length, breadth, and depth of the lakes. There are vast areas completely void of predator fish and other areas where the salmon, trout, walleye or other predators frequent. That’s a good thing. If the fish were distributed evenly in lakes the size of the Great Lakes it would be a very long troll from one fish to the next. 

The job for the fishermen, then, is to hunt down the places fish are concentrated and ignore the empty spaces. Just as in hunting for game animals, scouring the edges in the lake are great places to look. 


When most people think of the “edge” of the lake they think shoreline.

At times, right along the shoreline is a great place to fish on the Great Lakes—and for many species. Few of the top predators Great Lakers are after are structure-oriented, as are bass or pike. On the big waters, the shoreline effect usually has to do with temperature, food or current. 

brown trout great lakes crankbait trolling

A shallow diving crankbait trolled along the shoreline edge is a brown trout killer in late winter. 

Almost anywhere with a decent brown trout population or in parts of the lakes where coho salmon congregate in late winter or early spring, trolling just off the beaches can be crazy good. Even with only a weak, late-winter sun, warming will occur in the shallowest water from just off the beach to where it’s as deep as 10 or 12 feet. That slim column of warm water along the shallow edge of the lake will put browns and cohos into action. 

Along the beaches, I troll regularly the water deepens to about five feet from the beach outward, then a sandbar builds up to bring the depth up to about three feet.

Past this bar, the bottom slopes back down out towards the depths. I often position my boat just on or along the outside of this bar and use planer boards to position lures in the trough between the boat and beach. The opposite side puts lures over the offshore slope.

Some days the lures running closest to the beach do the best, other days the outside lures are hot and many days the results are mixed. My best lures are shallow-running plugs and jointed stick baits whether on the inside board or outside. Even when the lures are tracking over 12 or 15 feet of water, the surface water is slightly warmer and the fish are surface oriented. 


It’s not only in the spring when trolling close to shore when fish are oriented and prone to bite near the surface. Some fish, such as steelhead, are just plain surface oriented. On calm days, even in triple-digit depths, I’ve seen them swimming on the surface with their dorsal fins protruding from the water like sharks do in the ocean.

No doubt this is a throwback to their rainbow trout ancestry when bugs provided most of their food. Steelhead love to key on floating insects instead of the baitfish they could be gulping by diving just a bit deeper. 

Until the surface water gets OMG warm in mid or late summer, I always have a fluorescent red spoon or plug running just under the surface “edge” regardless of how much water is under the boat—usually, there’s one planing out to each side of the boat. It’s a rare day they don’t pick off one or more bonus steelies. 

bay edges fishing michigan great lakes

Shoreline structures such as these industrial walls and harbors at East Chicago, Indiana make plenty of current edges for fish to relate. 


Just as steelhead are naturally surface-oriented, some fish are naturally bottom oriented. None of the Great Lake predators fit this category so much as lake trout, but walleyes are on the bottom feeder list at times.

In areas or at times where fishermen are trying to avoid catching lake trout, avoiding positioning lures at or even near the lake bottom is as likely a way (not a sure way) to keep lakers off the line as any.

Doing so, however, can also cost those fishermen the chance of hooking other, more desirable salmon or trout, also attracted to the bottom edge of the lake. 

Plenty of browns, steelhead, and salmon (cohos in particular) swim belly to the bottom slurping up gobies and other bottom-dwelling baitfish. The same dodger and Spin-n-Glos run right at the bottom, expressly for lake trout, will dredge up this deep-down silver-fish.


When you drop a couple of ice cubes into a lukewarm glass of water, what’s the next thing you do? I always give the drink a quick stir to mix the cold water created by the ice and the warm water needing to be chilled. 

Why do I need to stir the drink?

Because of the physical propensity for waters of different temperatures to resist mixing. My glass of water will eventually get chilled, top to bottom and in a location where a tributary stream with water significantly warmer than the lake into which it flows, the waters will eventually mix and become uniform in temperature as well. Initially, however, they’ll resist mixing and there will be an abrupt water temperature edge formed. 

Fish are cold-blooded so if the water in which they are swimming is 50 degrees, their internal temperature is 50 degrees. This makes fish very sensitive to quick changes in water temperature. A temperature change of 10 degrees can be fatal and even a two-degree change is stressful.

The interface between areas with different water temperatures is an edge.

By and large, the fish on the warm side will stay in the warm, the fish on the cool side will stay in the cool. Quite often, the fish will swim along, following this edge, much like there’s usually a well-worn path around the fence of a pasture filled with horses or cows. They spend more time patrolling the edge of their world than wandering aimlessly through the middle. 

It’s not only predator fish working the cold/warm interface, it’s prey fish as well and on both sides of the temperature break. Though a fish will be hesitant to swim directly from warm to cold or cold to warm and stay there, they will often make a quick dart to the other side to nab a prey fish and then dart back before breaking a sweat or getting a chill.

When I’m working a temperature break on my boat, I try to stay right on the break initially, with lures pulled behind planers on either side. Usually, both sides produce. If one side or the other brings the most action, I’ll move one way or the other to put the most lures in front of the most fish. 

At stream or river outflows, this is a simple task.

The stream water is usually a different color than the lake water and the color line defines the temperature break. Where temperature breaks aren’t well defined by the look, stay on the edge by reading your surface temperature gauge while setting your plotter to leave a trail marking where you have trolled. Then zoom in on the plotter and just retrace the trail showing on the screen. 


Much of the summer over much of the Great Lakes the thermocline forms another important temperature. On some days it is vitally important. 

This narrow layer of water separates the cold water found deep from the sun-warmed surface water.

It’s an edge.

Find the thermocline “edge” with a Fish Hawk, Depth Raider or other temperature probes that attach to downrigger cables. The thermocline often attracts enough algae, plankton, and baitfish it’s visible on a sonar screen.

thermocline probe fishing downrigger

Underwater probes attaching to downriggers are a sure way to find the edges of the thermocline. 

Regardless of how you find the ‘cline, position lures just under it or just above it. Salmon and trout are cool water-loving fish and lurk just below looking for a snack. Suspended walleye do the same, but stay on the warm side. 


Predator fish love currents because they provide a conveyor belt-like supply of food washing along through the water. All the predator has to do is position itself just out of the current edge, keep an eye out for passing baitfish washing along and then darting into the flow to pick off easy meals. 

There are almost always currents present in the Great Lakes.

Some occur where major tributaries feed into the lake. The greater the flow, the more consistent the edges will be. The Niagara Bar where Lake Ontario accepts the entire flow from the upper Great Lakes is probably the best river current edge in the entire Great Lakes system. 

There are natural lake currents caused by the Coriolis Effect initiated by the Earth’s rotation. There are also wind-driven currents created by short bursts of strong winds or more often, several days of sustained winds from the same direction. 

Breaks to these currents that congregate fish don’t occur everywhere. But where they do, fishing these edges can be dynamite. 

Nearshore, look for long industrial break walls or natural points jutting out abruptly away from shore. These normally affect wind created currents more than the natural currents.

Often the fish attracting current edge off points or piers come and go.

A north wind may not create much of a current or much of an edge. A south wind or one from some other direction may make it the hottest spot you’ve ever trolled a lure.

steelhead fishing great lakes

Positioning a lure or two just under the surface can produce a bonus steelhead almost any day. 

Natural islands in the lakes can disrupt both natural and wind-blown currents. Again, the direction of the current affects where the current break occurs or if one sets up at all. 

Abrupt changes in water depth can disrupt natural lake currents and create an almost perpetual “hotspot” for fish to congregate. The “shelf” just south of Big Point Sable near Ludington and the “bank” offshore of Sturgeon Bay are both rapid, deep drops that always give fish an edge. 

An edge is what you need to seek the next time your fishing trip seems more like hunting than fishing.

Think like a hunter and hunt for an edge. The fish do.  

- written by Mike Schoonveld

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