“Now that’s a walleye,” my friend Sid Brown exclaimed as the trolling rod bent into a deep bend. Though we’d had prior action from yellow perch — walleyes —our target species, had eluded us during the initial part of the outing.

Sid grabbed the trolling rod from its holder and began steadily winding in the strong fish. A veteran troller, Sid knew not to pump the fish, which can result in just enough slack line to set the hooks free when winding in a fish with 100 feet of line out.

When the fish dove and shook its head, he simply paused while maintaining pressure. After a couple minutes the fish – a 23-inch walleye – was safely in the net. Several more would follow as the day unfolded.

The adventure took place late April on Crawford County’s Pymatuning Lake, one of the state’s premier walleye destinations and one that does not have a closed season. Statewide, the season opened May 1.

Our fish came by way of trolling crankbaits on leadcore line, a tactic detailed in last week’s column. In addition to several quality-sized walleyes, we also caught numerous yellow perch, white bass, crappies, channel catfish and a small musky. Shad-shaped crankbaits in perch patterns were most productive.

Mapping was a big component of our day. Though electronic lake maps that display on the screen of a marine chartplotter have been around for years, by and large they were lacking much detail for waters in our area.

Happily, that’s changing, at least with some brands of marine electronics.

For instance, a couple of years ago, Garmin Marine purchased Navionics, a third-party marine mapping company. In the months that followed, Garmin merged Navionics’s data with its own, the result being Lake Vu G3 maps which includes detailed maps of many area lakes including Pymatuning.

Since I run Garmin Echomap chartplotters in my boat, it’s what I’m most familiar with. It’s possible that other electronic marine makers like Lowrance and Humminbird now have access to improved maps for local waters as well.

Accurate, detailed mapping provides a huge advantage for the angler, particularly one that fishes structure away from the bank. Submerged humps, points, creek channels, bridges, and roadbeds are among the features that are often plainly revealed on maps.

Understanding how features such as these are laid out provides one with the ability to know where to position the boat and how to present lures.

In the case of our recent Pymatuning trip, after fishing a large, submerged hump with blade baits and jigs, and catching only a few perch and bass, we switched to trolling main lake basin areas.

Our first walleye came from 20 to 21 feet of water. We’d been marking fish on the sonar unit and catching some yellow perch and theorized the walleyes were likely feeding on these perch. So, our subsequent strategy was to continue to work this depth range.

Utilizing the chartplotter map made it easy to keep the boat in this zone. Without it. we’d have been forced to weave between the main creek channel in 25-foot depths, and the shallower inshore waters, consistently blindly adjusting to keep in the productive zone.

Leadcore line allows you to troll lures within inches of the bottom, where walleyes often are early in the spring, a task made much easier when you can keep the boat at a consistent depth.

Jeff Knapp is an outdoors columnist for the Butler Eagle