Sonar Scanning (Idle mapping): Scenario-based execution: boat position, landing spot, cadence, and adjustments

Unknown flat: draw three scan lines before running

On the map, mark three lines: flat top, breakline, and exit. First pass idle the breakline from the deep side, second pass cut across contours, third pass check the flat top. Start with low cruise within the device manual’s recommended range, keep steady speed; if the image stretches, check ping/scroll speed matching to boat speed.

Place the “hard bottom edge” waypoint at the side-imaging cursor, not by casually saving directly under the boat. When you see an isolated rock, scan it again from the opposite direction to confirm the shadow direction changes with angle while the target body stays put. A single-pass dark area could be terrain shadow; don’t name it a school outright.

Existing juice spot: save both fish spot and boat spot

After getting bit, first save the target, then save a boat-position point, noting rod direction and landing spot. Drag a 1/2 oz jig from soft bottom toward hard; each lateral drag 30–50 cm, pause, then pick up slack. Areas with consistent gritty feel mark the narrow sections to verify next round.

If the main line is getting pulled at a big cross angle, your waypoint and bait position are offset; reduce crosswind first, then re-mark. On return, don’t drive straight to the “fish spot”; go to the “boat spot” to reconstruct the path. Use different icons for the two to keep partners from navigating to the wrong one.

Clear, shallow water: stop where the scan says

When water is clear, fish are shallow, and they bolt as the boat approaches, don’t keep idling directly over the target just to get pretty images. First scan the outside to find grass edge and hard bottom, then back out to casting distance, and verify edges with a 1/4 oz minnow-style bait. Land past the target at least one sink-ahead so the bait is already at depth as it passes the target.

If you can see fish on the deep side but only bottom shadows on the shallow side, verify the deep side first; it’s not that the shallow has no fish, it’s that current observation is insufficient. Add a question mark to unverified waypoints and only change to a fish icon after real bites. Finish the fishing, then backfill scans to reduce pre-fishing disturbance.

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