If you can't make head or tail of this, it is a White Oak Rat Snake Elaphe obsoleta spiloides wrapped around the body of a squirrel. Squirrel's tail and hind feet are at left. Neither head is visible as Snake is trying to swallow Squirrel. Squirrel is very still and green bottle flies are already here.
I suspect Snake lay in wait along an oak limb above, blending in well. He struck Mr. Squirrel as he came in reach. The thud was them hitting the ground where Snake's plan was to finish off his meal.
Disturbed, Snake hissed his displeasure at me. You can tell he is not a rattlesnake because there is no pit between his beady little eyes, besides the different markings that distinguish a Rat Snake.
Satisfied that I'm coming no closer, he gave a little smile with his forked tongue still out.
Then he returned to his meal.
I left him alone to swallow Squirrel, intending to go back and get pictures of Mr. Snake (Miss Snake?) when he was all lumpy and full. When I went back he was gone and there was no sign of the Squirrel.
Two snakes in two days! Yesterday's snake was a Corn Snake. Fortunately both are of the Elaphe family and welcome in the garden to take care of rodents and such.
I'm careful where I put my hands and feet. While not poisonous, rat snakes will bite and the bite can get infected or we can react to the venom they use to kill their prey the way one is allergic to bee stings.