This falls more on the "behaviour" category of the forum...
I was taking a few shots of Anhingas feeding, and this one had a fish and lost it. A few seconds later she started ... I guess playing is the word... with a leaf. She picked it up, carried it, tossed it a couple times, then moved over to the shore to dry. She never actually tried to eat it (so I presume she knew it wasn't a real fish).
Or maybe she wanted some salad to go with her sushi.
Very strange.
Practice?
Trying to fool the observer humans that she hadn't really lost the fish?
Interesting behaviour. I was hanging on to see if other Floridians had seen this. It is possible the bird mistook the leaf for a fish or what you saw was an example of play, which is quite common in the animal kingdom. The most common interpretation of play is that it provides practice for the "real thing".