Thermoclines and Trophy Walleye

“Thermocline”. That word intimidates many walleye anglers on deep, clear lakes. The walleye that feed on cisco, smelt, alewife, etc. are usually plump and lazy, getting easy meals and rarely having to work very hard due to the sheer abundance of baitfish in many of these lakes.

So if these fish aren’t as willing to bite as a suspended walleye in 15ft of water at night, what it the trick? Well, that is a great question. You can troll crankbaits with dispy divers, snap weights, an unweighted setup, you can cast slip bobbers or vertical jig, you can catch a cisco and rig it on a bobber or dead stick. There are many ways to get a lure to the thermocline, but again, the issue is trying to compete with a million other baitfish for the walleye’s attention.

That is why I will find structure that intersects the thermocline. Shoreline is fine, but then you have to fish deeper than 25ft which can cause delayed mortality due to barotrauma. The structure I am referring to is more along the lines of humps and saddles (think narrows, between islands, etc.), or bars that are just above thermocline level. Fish that have spent the day patrolling the open basin will often swim right up and into these pieces of structure and that is why they are particularly vulnerable. There are less baitfish that shallow, so your lure gets noticed a lot easier. These areas can act as highways, especially when they are the only way fish can get around the structure. They are funneled in and will hit lures with lightning fast speed.

Every lake is a little different, so try live bait under a bobber, trolling, vertical jigging. But odds are, those special spots where isolated structure meets the thermocline will the be the best.