Elephant calves are quite clumsy after their birth and need to learn how to use their trunks. They cannot feed themselves with it yet and are nursed by their mother for the first year. During this time, they gain a good kilogram in weight each day. It is very important for them to grow quickly, as adult, healthy animals are hardly vulnerable to lions or crocodiles. If a predator comes dangerously close, the adult elephants form a circle around the young ones, providing them with good protection in the center.