Fishing 101: How to Use Fishfinder Features

By Jim Hendricks.

While trolling for tuna 30 miles ­offshore, all crewmembers scanned the water, ready to sing out at the first sign of feeding fish or bird activity at the surface. Meanwhile, a virtual crewmember was looking downward: our fish finder, pinging away, ready to sing out when the time came for action.

I had set an alarm in the machine’s menu to alert us of any echo returns from as deep as 300 feet. This eliminated the need for a human to ­constantly look at the display for signs of fish. Instead, we just needed to listen.

Sure enough, halfway through the morning, the alarm sounded, grabbing my attention. A quick glance at the screen indicated a school fish about 150 feet below the boat. I pulled back the throttle and told my two crewmembers to drop their Colt Sniper jigs straight down. As soon as the lures reached the marks, the anglers hooked up. Within 20 minutes, we had a pair of gleaming 45-pound yellowfin tuna lying on the deck.

A fish alarm is just one of many special features on a fish finder that help anglers locate more fish—or at least avoid missing them ­altogether. There are also several techniques to help maximize the effectiveness of these marvelous machines. Let’s look at four tricks that you can easily put into practice.

Fast Read
Dave Pfeiffer, president of Shimano North America Fishing, recently told me about a technique he uses when cruising along in his 32-foot SeaVee. He employs this in waters off Charleston, South Carolina (where Shimano is now located), but it works almost anywhere.

From the moment he leaves the dock, Pfeiffer keeps his Furuno NavNet TZtouch fish-finder mode on all the time, even during a long run to the offshore grounds. While the fish finder can’t mark fine bottom detail at cruising speeds of around 30 mph, it can pick up groups of fish, which appear like faint spikes or sprinkles. When Pfeiffer sees such marks on the ­fish-finder screen, he slows the boat and spins around to take a closer look, often finding an otherwise uncharted wreck, outcropping or ledge stacked with fish.

“You’d be amazed at how many new fishing spots I find like this,” he says. “And how many fish we catch on these spots.” Pfeiffer reports experiencing outstanding fishing for amberjack, cobia, grouper, snapper and more on these newly discovered hotspots, now treasured waypoints in his logbook.

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