Single hippo in a small pool of water making aggressive gestures to show its might. Hippos are by nature quite aggressive and you have to be careful if crossing their path on a lake or a waterway. Hippos are usually seen in large bodies of water, but this one was different. This hippo was in a small pool of water that was surrounded by a savanna. The hippo was making aggressive gestures to show its might. It would open its mouth wide and then make loud grunts.