A Pied-billed Grebe with a trophy sized Bream it just caught.
If you look closely you will see that the Bream's mouth is open, thus making it difficult for the Grebe to get the fish in its mouth.
Also note that the Grebe's bill is clamping the Bream's gills shut. I don't know if this deliberate. But it's a quick way to kill the fish by suffocating it.