How to Read a Fish Locator

How to Read a Fish Locator
Fish locators are highly technical tools used in fishing to help anglers see underwater. Also called fish finders or depth finders, these units display hidden terrain on a monitor and also identify the location of fish and often the size and even species of the fish. Fish locators use sonar to render images, which means they're not always foolproof--most of the visual renderings are educated guesses based on the general shape of the object being rendered. They are nonetheless very helpful to all fishermen, from novices to experts.


Difficulty: Moderate

Step 1
Familiarize yourself with the types of symbols used on the fish locator's monitor. Almost all locators produced these days graphically represent the estimated size of the fish found underwater, and many use differing shapes or symbols to represent the species of the fish. The symbols used are almost always fish-shaped. Read the user's guide to understand what the different symbols mean, as this will be essential to interpreting the information.
Step 2
Use automatic depth reading. Unless you are an expert who has used your fish locator extensively, manual reading can be difficult to do. Automatic depth reading will let you know how deep the water is, which is important when fishing for lunkers and other bottom-feeders. You will find the depth always displayed in one of the corners in either meters, feet or both.
Step 3
Watch the screen for objects or fish that don't move. This is a strong indication that the object is inanimate. Some locators, particularly less expensive models, can be prone to mistaking rocks or other objects as fish, throwing off your reading.
Step 4
Search for objects such as rocks or reefs that provide crevices for fish to hide. These are often popular places for fish to congregate, and many fish locators will have specific symbols for these appealing terrain monuments.
Step 5
Adjust your locator for sensitivity based on how abundant or sparse objects are. If the screen is inundated with inanimate objects, reduce the sensitivity at least 10 percent. If you are struggling to find anything in the water, slowly increase the sensitivity until you start seeing objects, then determine if they are fish or objects by watching for movement.

Article Written By Jonathan Croswell

Jonathan Croswell has spent more than five years writing and editing for a number of newspapers and online publications, including the "Omaha World-Herald" and "New York Newsday." Croswell received a Bachelor of Arts degree in English from the University of Nebraska and is currently pursuing a Master's of Health and Exercise Science at Portland State University.

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