Interpreting Targets on Your Flasher

Jake Williamson writes:

Hey Joel, I really enjoy reading the articles you have been posting on your page. I appreciate the helpful advice I gather from them! I have been using a flasher for a few years now and it has made a huge difference in landing fish on the ice. One of the struggles I have is interpreting what I see on the bottom while searching holes for fish. A lot of times I interpret lines as fish while later finding they are just weeds along the bottom. Do you have any advice or links for better interpreting what we see on the bottom?

Thanks for the question Jake.  I know what you mean, especially when you’re in search and destroy mode.  You’re bopping along and see some lines here and there, and decide that you should fish them.  As you later find out, those lines are stationary and don’t add up to much. 

One thing to key in on is the strength/color interpretation of the target or mark.  On a Marcum, only the densest of weed growth and usually only cabbage or other high-climbing greenery that you see up in the water column a bit will actually show up as “red.”  Most weeds along bottom will always be green or weaker sonar returns.  Fish, especially anywhere near the middle of the cone angle will show up as distinct red targets, usually separate from bottom instead of faint signals that flicker or seem attached to bottom.

In extremely shallow systems (less than 10FOW), it can be difficult to drill right on top of fish and have them stay directly below you.  That can account for not finding or seeing much when you’re hole hopping.  For everything else, you’re looking for more than just a flicker of small hint of fish, you’re looking for strong red returns that are distinctly separated from cover or the bottom. 

In terms of reading bottom content or hardness, a larger or longer tail behind the leading edge of bottom indicates soft muck or mud.  The thinner that red bottom target, the more likely you are to be on sand, gravel, or rock, in that order progressing from thick to thin. 

Nothing beats time on the water with a sonar, but an underwater camera is an invaluable tool to help you visually pair what you’re seeing on sonar, with what you’re mind’s eye interprets that as being.  Work with them in tandem, and you can get really good with your sonar!    

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