Strange image on my Side Imaging sonar

While trolling Wed. I went under the bridge at the section closest to the North shore and had a strange image appear on the screen. It was a donut shaped object that looked to be 5-8 feet in diameter and maybe 12inches thick. It's hard to tell sizes but I had the bridge pillars on the screen as well and the circle was about half the size of the pillars. Then there was a smaller circle maybe 8 feet out in front of it. They were 15 feet down. It looked like a bait fish ball on my regular sonar, but a bait fish ball on side image looks like a cloud if they are small fish and if they are bigger, you can make out the fish. This had the cloud look but was in the shape of a donut.

I came back through a little later and it had moved from the bridge to out in front of the wheelchair platform, which would be against the current and wind direction. The odd thing was the size and spacing of the two circles looked to be the same. I was wondering if it was bait swimming in a circle like you see fish do on TV in the ocean. Anyone have any ideas. I need to figure out how to use the picture function on my side image unit, that way I could have posted it.

Well, on another note, got a nice 38"er trolling. Put up a great fight and swam off strong.



Jarrod

Great fish Jarrod and nice visor!!! :) Congrats, and I really do not have a good answer on your electronics question. Sounds weird to me. Could have been baitfish, but who knows?

Thanks Tom, that's my new lucky visor.

I took Dad out for some muskie hunting and he got a 31''er tonight. We lost another about half way to the boat.

We were trolling tight to cover and one of the rods had a short rip, then another. I had been watching my side imageing and new we were not hitting anything, so I figured a skie was following and kept grabbing the lure. I did a hard turn towards open water and gunned it. As soon as the lure turned, FISH ON!! We lost it but it was cool to get a strike like that.

Jarrod