Good job guys ...

The bright area is indeed a riprap jetty ...

The structure seems to be all man-made (including the porcupine fish attractor) ...as the entire rest of the bay is nothing more than flat mud ...

This is one of those honey holes that should be cast to from a distance ... (That is when you can actually see some fish echoes milling around the structure) ...

And there is a little structure that passed right under the boat to the left just a little ... As indicated right at the bottom of the left water column at the bottom of the SI image scroll ...

There's also a few fish echoes in the lower left of the screen ...but I think those were Asian carp from the size of the white dots ...