Surprisingly hippos are herbivores. Their main source of food are different species of grass. You will often find them eating grass on plains, often by water. Hippos sometime travel up to 5 kilometers in the night to reach feeding grounds. They follow paths marked with dung. Hippos don't use their strong teeth for eating. Instead, they have strong lips to clip the grass and cheek teeth to chew. Hippos eat around 40 kilograms of food, even though they're huge. This is because they do not use much energy floating in the water. Hippos that live by human settlements often eat the rice plants that they humans grow as well as trample the other crops.