Sonar Exploration to Catch More Shallow Fish
Blog by: Matt Snider 6/19/2021
I fly fish for anything that swims. It’s a choice I make because I really enjoy flinging noodle lines around, tying/designing (and buying) flies to imitate food sources, and mostly because I am better at fly fishing than I am spin fishing. I know it is not always the best way to catch fish. But I love it. I am sure that’s why you do what you do too – you understand your gear, and you’re good at it, and you enjoy it.
I do also fish conventional tackle. Especially when it comes to muskie - covering water and structure quickly to find active fish is one of my primary strategies. I do fly fish for muskie also, but only when I've figured things out or have someone on the boat with me crazy enough to do it. I also vertical jig to deep fish oriented with baitfish schools, and I am getting better at that. And then there’s ice fishing – I mix it up with conventional tackle and flies.
I also troll. When muskie fishing I like to troll strategically, typically when the sun is high, air is hot, and water still. With fish setting up further off structure typically, I’ll troll a big deep diving crankbait not far behind the boat, and zig zag around structure with tight turns bumping rocks and sticking tight.
When not fishing muskie, my trolling tends to be for the simple reason of keeping a line wet while exploring. I like to scout and map and mark spots and fish in an effort to get to know a lake. And why not have a lure in the water while doing that? When I show up to a lake I don’t know well, or haven’t fished in a while, it is important to me to get a feel for what’s going on. You can stare at a flat body of water and only wonder what’s underneath, or you can spend some time becoming familiar with it.
And so I troll. Even if my objective is to catch fish on a fly I’ll drive around, sometimes for an hour or two (or more admittedly) and glue my eyes to my sonar. I log the sonar and stick to a pattern so I can eventually turn this “boring” procedure into a contour map that will benefit me greatly down the road. I recently began using the Lowrance Genesis Live mapping to help me see what I want to see while still at the lake.
I add waypoint icons for significant fish marks and any structure I find. Weeds are marked with the “chicken feet” icon – I am not sure that’s the official term but that’s what I call them – which look like weeds, and rocks with different colored Xs based on size/depth. I mark fish on the bottom different than suspended fish, and mark baitfish and larger signals with different icons.
When I am done I can back out of the map zoom, hide my cluttering trail, and get a better idea of where these larger fish and baitfish are congregating. It surprises me that there is a commonality in many of the lakes in that the food and game tend to be amassed in certain sections while devoid in others. And those populated sections are where I turn my focus.
Many times there will be shallower structure and cover near these areas. I go inspect these and break out the sinking line with clousers and/or buggers to imitate the baitfish and crayfish that are often the most apparent food sources of choice for the big predatory warmwater game fish. And I start pounding the weeds, edges, rocks, shorelines, brush, etc. in these areas.
Same goes for when I am muskie fishing. The structure I know well that I’ve spent years mapping and learning are usually more active when the deeper surrounding body of water is more active on the sonar. So I troll, take mental notes, and then go cast structure.
It is a technique that requires patience but can pay off. When fly fishing, you just cannot cover as much water quickly as you can with conventional tackle. It helps when I am alone to carry out this sort of practice, as I have no pressure to appease anyone else’s desire to “just go catch fish.” Just my own. And I know that if I do this, chances are I will find fish.
This has proven successful recently on several occasions. I fished John Martin which I had not fished in at least 15 years, and ended up on some good white bass and crappie in what seemed to be the middle-of-nowhere in 14-15 FOW. At Jackson Lake, another one I hadn’t fished in years it was the same – mapped and trolled and found fish and hooked a couple wiper in the middle of nowhere. I went back and casted with flies and immediately got two wipers on one rig… what a great fight! I fished Boedecker and while I was mapping the main basin I kept noticing fish in a certain area. I went back and fished just off the seemingly featureless shoreline nearby and got into walleye, crappie, and white bass. Same at Douglas – walleye, wiper, and carp – yes surfacing carp that are an absolute blast to hook and land on a fly rod… which I would not have seen from further out had I not moved into the shoreline. And two lake trout lakes that I have spent hours mapping and marking produced for me through the ice and open water based on fish mark concentration.
I cannot tell you why the deeper fish were where they were, and why they were not where I might’ve thought they’d be. But the sonar exploration/scanning was key in getting to know these lakes better. They are ever-changing, so next time I may go back and find a different trend. But then again I’ve seen many times that fish are in the same sort of deep areas next time I visit the lake.
Unless you fish one body of water year-round, this kind of research and exploring will do you much good in getting to know a body of water and get you onto more fish. Why are guides so good at putting clients on fish? They know their lake(s) better than anyone. That goes a long way, and then all you need are skill, know-how, and the right tools to catch fish. Get to know the lake you are fishing and you will improve your chances of catching fish significantly.