About Properly Using Fishfinders

A fish finder uses sonar waves to show the depth of the water you are fishing and what objects are in the water. You can maximize the effectiveness of fish finders by placing their sensors in prime locations, setting sensitivity levels to the correct degree, and learning how to read the data correctly. A fish finder may also include GPS capabilities for reading the lay of the land and temperature devices that indicate how hot or cool the water is.

Facts

Garmin Fishfinder 160C

Fish finders are electronic guides that help fishers measure things such as the depth of the water, what the ground beneath the boat looks like and what kinds objects are in the water. Used properly, fish finders can be a great asset, showing experienced fishers where fish are most likely to hide and where the primary fishing places are along rivers and in lakes.

Fish finders have several different modes, including a demo mode, an automatic mode and a manual mode. You will want to make sure the device is off of the demo mode, but it is up to you whether to use the automatic mode. This mode generally takes care of sensitivity, speed, resolution and how wide the "window" of the finder is, or the square of water that it examines.

Sonar

Fish finders use sonar to judge the distances to the bottom of the lake or river and the size of objects floating in the water. You will usually need to mount some sort of sonar device manually when setting up your fish finder. You can set this transducer device on the bottom of the boat, centered near the motor, or you can set it up inside the boat inside the hull, where it is separated from the water by only one layer.

If there is a sensitivity setting, you can set it to a degree you feel comfortable with (usually a percentage) and then experiment. Prime sensitivity usually lies between 75 and 95 percent. Sonar is distorted by the type of water, whether saltwater or freshwater, along with winds, currents and silt deposits, so the performance depends on what type of water you fish in. It is best to never take the results of sonar too seriously.

You will also need to set the speed of your fish finder, unless you want to simply program maximum and minimum levels for the automatic mode. Will you be trolling? Will most of your fishing be done when the boat is stationary? This will affect your speed decisions.

Screens

There are two important considerations when dealing with the screens of fish Finders. The first concern is the type of screen you are looking at. Finder screens can range in type from a simple black and white LCD display to different types of gray-scale and color views. The most important feature to look for is durability and readability. If you can read a black and white screen in the sun and not worry about it breaking or failing during the rougher times, don't hesitate to use it instead of a fancier and more fragile model.

The second consideration is the "window" positioning. This feature depends on how wide an area you have your fish finder set to scan. A wider area will give you a better view of the upcoming depth and any larger groups of fish, but the finder will have a difficult time telling fish apart from one another and can misjudge objects more easily. A smaller window gives you better resolution but also less to see. Thirty to 40 feet is considered a good average window size.

GPS

GPS Fishfinder

Certain fish finders have a GPS function to help pinpoint precise locations. It is important to note what a GPS will and will not do. A GPS cannot help you immediately judge depth or differentiate between fish and debris. A GPS tracks your location with a great amount of accuracy and shows topographical maps of the surround land, both above and below water.

This is helpful when you find a particular spot on the river you like and want to return there -- you can record the longitude and latitude with the GPS and have it in your fish finder for future reference. A GPS can also help you find fishing spots you have not been to before, giving you very precise maps of your surroundings and showing locations you have preprogrammed.

Temperature Readers

Some fish finders come with temperature-reading devices that show you the temperature of the water. This can be a very useful guide if you are experienced in different species of fish and what type of water they prefer. If you want to use this feature, you can buy a manual or book that shows the temperatures various fish prefer for spawning, feeding and other activities.