This time of year they spend 90% of their time doing absolutely nothing, 5% thinking about mating, and 5% thinking of food.

Hmmm, sounds a lot like a teenage boy.
You may not notice at first either, and this is exactly how it happens. Click the image to view in full size.
There are 2 hidden Alligators within a few feet of this Heron. Even knowing they are there it is hard to see them.
None had moved while I was watching, they all may have stayed that way for hours. Patience is how both Alligators and Herons hunt.