I think it's a geoffroy's side necked turtle (Phrynops Geoffroanus). On the website they say that they have this species at the park, and I did a photoshop comparison between the screen shot and a clearer one.
4:34 am here on the west coast of the states. I'm watching an isis program and though it's recorded, the forum keeps me awake. Guess I'll end up sleeping all day and not at all ,(unless there's no rain.)