September 03, 2015
The image shows structure, a bait school and larger predatory fish port and starboard.
It's by no coincidence that an angler's day, during the summer months, starts early. Cooler morning temps make it favorable for bass to cruise the shallows in search of prey. This is where most fishermen concentrate their efforts because of the visual clues. Fallen trees, lily pads and other emergent vegetation offer cover for fish and casting targets for anglers.
As the sun rises, it doesn't take long before rays penetrating the surface to warm shorelines and flats well above a fish's comfort zone. A slow migration begins as bass retreat to the cool sanctuary of deeper water. Largemouth tend to school on ledges, dropoffs and deep hydrilla walls such as the edge of a road bed. Find one of these areas and you can extend your fishing day well into the afternoon. I was recently faced with this scenario and rather than head back to the marina and wait until the late afternoon bite, I decided to press into service a new touchscreen fishfinder/chartplotter that I had installed on the dash of my bass boat.
The unit is a Lowrance HDS-7 Gen2 Touch. Standard features include built-in charts with a super-accurate internal GPS and a broadband sounder, but the most useful feature is its StructureScan HD sonar imaging. Bringing this high-definition bottom imagery to bear requires an optional StructureScan HD transducer. Once initiated, you will enjoy picture-like 180-degree views of structure and fish below your boat with the ability to see out to each side up to 600 feet.
Traditional fish finders use a cone-shaped signal emitted from a transducer to gather echoes directly below your boat. Obviously the HDS-7 has that same capability, but being able to send those same fish-locating echoes to the left and right of the boat allows you to create a super wide image of bottom contours and fish. Covering a larger amount of ground with each pass is the unit's biggest advantage when it comes to fish finding. The high resolution picture that the unit compiles lets you identify types of structure, schools of bait and larger predatory fish.
I started by using the mapping feature of the unit to find a location of the lake that had a shallow flat, adjacent to deep water. Big bass forage in shallow water because of the abundance of baitfish but like to have close access to deep water for security and cooler temps. Paralleling the drop off I was able to scan an area starting on my left from 5 feet down to 11 feet, beneath the boat, out to the right extending into 14 feet of water. Reading the StructureScan picture takes a little getting used to. The dark area in the center of the display is the water column between the boat and the bottom. The shaded part of the picture, to either side of the center, is what's on the sides of the boat. A range scale on the bottom of the display shows you how far you are looking to the sides. It doesn't take long to recognize what you are seeing and you will be awed by the incredible amount of detail the HDS-7 is able to display.
On my first pass I located a school of fish suspended in 7 feet of water. The unit's touch screen made it easy to use its TrackBack feature that allowed me to scroll back simply by swiping left to right on the screen. With the newly discovered school of fish back in view, I tapped the screen which assigned their position a waypoint that was saved. I shut off the outboard, lowered the trolling motor and let the boat drift off of the spot. A live shiner, rigged 5 feet below a foam bobber, was deployed and my wife Cheryl watched intently as the bobber trailed behind us. The Lowrance Goto cursor feature directed us back to the school of fish which came into view as the boat passed over them. The bobber was immediately
pulled under confirming our strategy and the HDS-7's ability to help an angler locate midday fish in deeper water. The Lowrance HDS-7 Gen 2 Touch has a host of other features to enhance your boating and fishing experience. It is also available in two larger sizes that include a 9 inch or 12 inch screen.
Other manufacturers have units available with similar side scanning features such Humminbird Side Imaging, Raymarine eS series, and Garmin echoMap. FS
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First published Florida Sportsman July 2015