What do Bait Fish Look Like on a Fish Finder a.k.a. Bait Balls Posted on June 17, 2013
Everybody wants to know what a fish looks like with their sonar. The next question is, what do baitfish look like on sonar a.k.a. bait balls?
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Would you like to find walleyes faster? Read Bruce Samson's magazine article about how to use sonar at faster speeds.
Everybody wants to know what a fish looks like with their sonar. The next question is, what do baitfish look like on sonar a.k.a. bait balls?
Finding fish at fast speeds is one of my secrets to catching fish. Fish concentrate in certain areas and aren’t found everywhere. You can hunt for them at 2 mph or you can do it Doc’s way and search for them at 20 mph. I will show you how to high speed fish and how to make it useful. This method pertains to all species of fish.
Fish are shown as horizontal lines when the boat is stationary, arches when the boat moves slowly and as vertical lines when the boat moves fast. You can also change the way a fish appears with the chart speed but a fish arch will still change at different speeds no matter what your chart speed is set at.
You may ask yourself - what do small fish look like on sonar? It is not an easy answer. Sonar determines size as echo strength and displays echo strength as different colors and how thick the fish arch is. Echo strength is different from targets at 5 feet or 20 feet from the transducer because sound get weaker as it travels through water. This is why auto sensitivity turns the sensitivity higher in deeper water. I have some examples of perch on this tutorial.
Fish like rocks and one of my favorite fish to catch likes boulders (Smallmouth Bass). After we figure out the fish are relating to boulders, we need to find more spots with rocks and boulders so we have more choices. Maps help because if the best rocks are at 15 feet, we can find 15 foot spots on the maps. You must have high definition map cards (Navionics, LakeMaster and Lowrance Insight Pro/HD) to have accurate 15 foot depth contours.
Why does my screen show vertical lines on it when I turn on my other sonar unit or when someone is fishing near my boat? When two sonar units are sending sound at the same frequency you can get crosstalk. Each transducer is sending (pinging) and receiving sound. Sometimes one sonar unit will display the other sonar units pings sonar and you will see vertical lines. Since the cone shape of the sound from a transducer gets larger as it goes deeper you get more overlap of cones in deep water. In shallow water you get less or no crosstalk.
You find fish at 20 mph with old flashers, Lowrance LCX/LMS models and the new HDS models.
The first images shows fish with the LCX from 2007. I would tweak the setting to get these images by using the maximum ping speed, slightly increase the Colorline and manual sensitivity and use the blue background palette. Finding fish at high boat speeds was difficult to unless I tweaked the settings.
If you see lines coming from the bottom to almost the surface at an angle, they are air bubbles. Notice the speed of 0.4 mph, I rarely see bubbles unless I am moving slowly. It is easy to confirm on calm days by watching the water surface for the bubbles.
What are they and how big are they?
We want sonar to give us the answers to these questions but it isn’t easy. You must know the location, type of fish in your system, and how to determine size with sonar.
Sonar only gives you the echo strength of the target and displays it-it won't make identifying fish and their size with sonar easy. Sensitivity can change the echo strength and depth range changes the way the fish are displayed (fish in a 10 foot scale are larger than fish on a 100 foot scale).
Determining size of fish is difficult with sonar - but surely, you want to know what big fish look like on sonar. This image shows big fish I was targeting this day and this is what I would see on the sonar. Notice the DownScan and the traditional sonar show a thick band and this is the best way to tell size.
