At times I’ve mentioned finding surprises in shots I was not aware of at the time. It’s usually something in the background that was unimportant.
Well here is another, but big for something not important.

On the other side of the water, across from the birds, is a big Alligator. About 10 feet ( 3 meters) big. I would think something they were aware of.
Shadows had fallen on part of the marsh, the big guy in them.

How do you miss something that big ?