Humminbird Side image interpreted
Here is a image from the Humminbird 1197 with "my" interpretation.
The picture is taken going off a steep ledge that has a hard bottom. The ledge goes from 22 to 32 feet.
The red circle is a nice brush pile up on top of the ledge.
The yellow circle is nice tight bait ball suspended high in the water column.
The blue circle is the sonar shadow created by the tight bait ball.
The yellow circle is what I find quite interesting. I think it is bait being attacked by fish of some kind.