Can you expand your view of the underwater world without breaking the bank?
What’s the best advice never spoken when it comes to catching yellowfin tuna? Troll directly over the school of fish. Sure, that would help, but this advice is utterly useless since you rarely know just where that school is until you get bit. At least, that’s the deal if you’re fishing with status-quo tech.
Case in point: we’re trolling aboard the Talkin’ Trash, a 58’ custom Carolina, when the captain suddenly makes a 90-degree turn to starboard. He gooses the throttles for a few moments, pulls them back to trolling speed, zigs, zags, and BOOM! Three rods go down and start singing almost simultaneously. He leans over the edge of the flybridge overhang, snickers a bit, and says “I saw ‘em on the Omni.”
Furuno’s CSH8LMK2 360-degree Omni sonar, developed for commercial fishermen but being adapted by some segments of the recreational market in recent years, is in many ways the holy grail of offshore fishfinders. With hundreds of individual elements in a transducer that drops down two feet beneath the hull when you flip a switch, it gives you a 360-degree scan at up to around 5,000 feet around the boat. It’s very much like looking at underwater radar with almost a mile of range. It also costs more than some 26-foot center consoles (including installation you’re going to be well over the $100K mark) and requires a boat big enough to house the rather enormous sonar tube that the transducer retracts into for cruising. For 99-percent of us, how helpful Omni may be is completely moot.
For Those of Us Living in the Real World
This doesn’t mean, however, that Joe Average offshore angler can’t expand his or her visual acuity beneath the waterline with a 360-degree view of the undersea world. The most obvious option is stepping from the tech developed for commercial vessels to the tech designed for recreational vessels in Furuno’s lineup, with takes you to the units commonly described as “searchlight” sonar, like the CH-500. The main difference between omnidirectional and searchlight is that omni blasts out its 360-degree pattern all at once (every half a second at a 1,000-foot range), while searchlight scans the water in a rotational pattern (which takes more like 14 to 18 seconds at 1,000 feet). It still has built-in motion stabilizers to provide a rock-solid view in rough seas, and it still allows you to look 360-degrees around.
Shifting to this sort of option, rather than needing the space for a housing that allows the monstrous 180-pound transducer two feet of movement, you’ll need to accommodate more like 16 inches for a 90-pound transducer. And as for cost, you can count on it being around one quarter to one third of the cost as compared to an Omni, with the installation job included.
Hybrid Solution
Another (very) scaled down solution providing 360-degree visibility is available to boats with bow-mounted trolling motors, which have become a bit more common on the offshore grounds these days thanks to the increasing popularity of hybrid boats: real-time imaging. For 2022 Garmin has rolled out LiveScope XR, which boosts saltwater environment range out to 350 feet. That won’t help you one iota when it comes to trolling for tuna, but it could come in handy when you come across a big weed paddy or chunk of flotsam and want to see if and where any fish may be holding under or around it. Real-time imaging could also help you keep track of a school of fish after initially locating it.
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Garmin does also offer a Panoptix through-hull transducer which will get you those real-time images. Since it’s a fixed mount, however, you’ll only see 360-degrees around the boat if you turn the boat in a 360. And at least for the time being, range on this transducer is just 200 feet.
One downside to consider about all of these options is that they take constant attention to be used effectively. Unlike traditional sonar they don’t scroll, so you can’t glance down every so often and hope to see something you went by a few moments ago. If you miss seeing the mark you’ve missed it. And you can count on a big learning curve being required to effectively interpret the display and adjust the sonar for the best effect.
Is it fair that those guys in their 60-footers can accommodate and afford the same sort of uber-techy fish-finding ability found on factory trawlers? Heck no. But if they can get it and use it to catch fish more effectively, you can bet they will. And whatever sort of boat you own, you’d be crazy not to do the same — with whatever level of 360-degree vision you can arm yourself with.
