African or Cape Buffalo (Syncerus caffer) in stream, West Tanzania.
Vicki and I were drifting off to sleep the other night when we were startled by one of these Dagga Boys ("Mud boys") scratching against the wood frame of our tent platform. From inside the canvas, we listened to him breathe heavily and munch wet grass. Eventually he wandered off. We slipped away under the covers. All's well that ends well.
Never mind the lions, an excommunicated old bull is the most feared animal of the Serengeti. Its power, speed, and unpredictable nature have given it the nickname, "Black Death."