Calves suckle from their mothers for about 18 to 24 months, although they may begin eating fish and squid at about six months. During the long suckling period, the mother teaches the calf how to hunt and behave, much like humans teach their offspring. Dolphins hunt for fish and squid and often cooperate in catching these prey. A group will surround a school of fish and dash in one at a time to gorge themselves. Although dolphin eyesight is good, long distance vision is reduced underwater.
Echolocation is as important to dolphins as sight is to most land mammals.
It provides information such as water depth and the position of food and rocks. There is even evidence that some dolphins use powerful sound waves to stun their prey, making the prey easier to catch. Dolphins do not have a sense of smell, but they can taste quite well and their skins are very sensitive. With these senses they are aware of where they are through feeling different water temperatures or tasting water types. This is useful if sight or echolocation are restricted.