Basic fishing sonar devices locate and mark the depth of fish under a boat, but modern devices can also help you understand how water depth, contours, structure, and water temperature affect fish habits and patterns. Some are also GPS enabled with mapping functions that store waypoints so you can return to places you caught fish before and navigate home. Here are a few additional notes on how these features can make you a more effective angler.

Great Value

This model is also ideal for canoe-fishing setups. Garmin

Fishing sonar displays depth, structure (such as slopes, hard or soft bottom, rocks), depth contours, and water temperature information, among other details. When fish icons appear on the screen, or if you catch a fish, note all the other data because it tells you where you might find fish elsewhere that day. For example, if you find largemouth bass congregating midway down a slope in 15 feet of water, chances are good you’ll find bass in other locations with similar characteristics.

Premium Pick

This device records your routes and boat speed for later reference. Hummingbird

Some fish finders can save your locations—something you’ll want to do if you catch fish at a particular spot. Knowing the places where you caught fish over time is valuable intel because fish behaviors and patterns change throughout the year.

Also Consider

This model has an SD card slot for saving additional maps or waypoints. Humminbird

Fish sonar with GPS and mapping features that show exactly where you are on a lake in real-time provides several advantages. The first is easy navigation. You won’t waste time figuring out where you are on a large body of water, how to get to your next destination, or how to get back to the dock or ramp. Another is the ability to identify areas that may hold fish. Lake maps detail underwater depth contours, so if you find fish hitting at a certain depth, you’ll have an easier time finding other areas with the same depth and rule out areas that probably don’t.