Active Sonar: Learning What Fish Want

By Jim Davis

As a lifelong diver, I’ve spent years exploring the underwater world, watching fish move through their environment and observing how they react to predators, currents, and changes in light. Diving gave me a front-row seat to the intricate behaviors of aquatic life, and it taught me patience and curiosity—two qualities that have shaped my approach to fishing. When I transitioned to kayak fishing as a tournament angler, I carried those lessons with me. Recently, I added active (forward-facing) sonar to my toolbox, and it has taken my understanding of fish behavior to a whole new level.

Active sonar works by sending sound waves into the water and displaying real-time images of what’s happening below. It’s like having underwater vision, showing fish movements, structures, and even how fish react to your bait. For someone like me who’s spent hours submerged in the water observing fish firsthand, sonar feels like an extension of that experience. It allows me to see what I used to watch while diving—how fish interact with their surroundings and respond to different stimuli—but now from the seat of my kayak.

One day while fishing for walleye, I started with a blade bait, which is usually reliable for triggering strikes. As I worked the lure through the water, I noticed on the sonar screen that the fish were scattering away from it. This was surprising because blade baits are designed to mimic distressed baitfish, which typically attract predators. Watching their reactions in real time made me realize that something wasn’t right—they weren’t interested in the flash or vibration that usually draws them in.

I switched tactics and tied on a spoon paired with a Sonic BaitFish lure. The spoon’s fluttering action mimics an injured baitfish perfectly, and its reflective surface creates flashes of light that catch the attention of predatory fish. But even with this adjustment, the walleye followed the lure without committing to a strike. Seeing this behavior unfold on the sonar was eye-opening; without it, I might have wasted hours fishing with presentations that weren’t working.

Determined to figure out what they wanted, I tied on a Wally Pop Crawler—a slower worm harness presentation—and dropped it down. Almost immediately, I saw a fish follow closely behind it on the screen. This time, it struck. That moment was a reminder of why I love fishing: it’s not just about catching fish; it’s about solving puzzles and learning from each trip on the water.

Sonar has transformed fishing into an interactive experience where every cast is an experiment and every strike teaches me something new. It allows me to test different lures and presentations while observing how fish respond in real time. This feedback helps me adapt quickly—whether it’s changing retrieve speed, switching colors, or trying a completely different bait—and makes every outing more productive.

My diving background has given me an appreciation for how fish behave naturally in their environments. When you’re underwater with them, you notice things like how they use structure for cover or how they position themselves in currents to conserve energy while waiting for food to drift by. Active sonar complements this knowledge by showing me these behaviors as they happen during fishing trips. For example, I can see bass holding tight to submerged logs or walleye suspending near drop-offs—all without disturbing them.

Fishing becomes less about luck and more about strategy—an ongoing challenge that stimulates curiosity and problem-solving skills. Every trip is an opportunity to learn something new about fish behavior or refine my techniques based on what I see on the screen.

The Importance of Note-Taking

I keep a detailed logbook on my phone, recording everything from weather conditions to lure performance. Over time, patterns emerge: how fish behave during specific seasons or under certain water conditions. By reviewing past notes and combining them with sonar data, I can even more accurately predict where and how to fish more effectively.

Sonar as a Placement Tool

In a kayak, efficiency is key. Unlike motorboats that can cover vast distances quickly, I rely on sonar to pinpoint productive spots before making long paddles. Once I find fish on the graph, precise placement becomes critical. Watching how fish interact with my bait on-screen helps me adjust my positioning and presentation until I get it right.

Time Management: The Tournament Factor

In tournaments, time is everything. Sonar helps me manage my time wisely by identifying productive areas faster. I plan my day meticulously:

1. Start at the farthest spot and work my way back.
2. Use sonar to determine which areas are worth fishing longer.
3. Leave enough time to return to the dock without missing weigh-in.

This disciplined approach ensures I maximize every minute on the water.

A Never-Ending Learning Curve

Active sonar has revolutionized how I approach fishing from my kayak. It’s not just a tool; it’s an extension of my curiosity. With every outing, I learn something new—that’s what keeps me coming back for more. Even without technology, I approach fishing like I would putting together a puzzle—learning from each element and adjusting as needed. Ultimately, fishing success lies in one’s ability to think critically, stay creative, and embrace the challenge of understanding fish on their terms.

Every time I prepare to fish, I feel like an explorer—just as I did when I first put on that diving mask years ago. The thrill of discovery never fades; it only deepens as I continue learning from each cast and each moment spent on the water.