Written by Ryan Ketter, Courtesy of Fishing with Maps by Fishing Hot Spots

Ways a depth finder enhances a fishing map:

  1.  Knowing a precise location – Your depth finder agrees with your Fishidy.com map.
  2. Updating your fishing map – Navigating with a fishing map and a depth finder tells the angler if his map is accurate.
  3. Finding specific locations and structure – A depth finder is necessary to confirm that exact location
  4. Visualizing a 3-D image – Projects enough data for an angler to create a mental view of the subsurface environment.
  5. Staying on edges with fish – Weed edges and breaklines are outstanding places to catch fish and an angler must have a depth finder to stay on top of them.
  6. Estimating distance – Depth finders display speed and distance traveled on screen.
  7. Locating fish – A depth finder will tell you whether fish are present or to motor on to the next predetermined area to fish.


Depth finders have become an integral part of every angler’s tools over the past decade or so. The term depth finder refers to a device utilizing sonar. Sonar emits high frequency sound waves that are inaudible to fish and humans. These impulses strike an object and reflect back to a receiver. The receiver measures the time it took for the impulses to return and continually calculates the distance between it and the object. Screens, graphs, or calibrated flashes display distance. The data you obtain from a depth finder screen, in part, includes: bottom composition, bottom terrain, depth, structure type and configuration, presence of fish, size of fish, and submerged weeds and wood. With the bank of information a depth finder furnishes, savvy anglers can create a complete representation of the fish’s world—a picture that will allow them to catch more fish.