Dolphins are small toothed aquatic mammals with superb hearing that live in saltwater and freshwater environments. Dolphins communicate with many different vocalizations, such as clicks and whistles, have advanced hearing that works underwater or above water, and can track prey using echolocation. The smallest dolphin, the Maui Dolphin, is only about 6 feet (1.82 m) in length while the largest dolphin, the Orca, can grow up to 31 feet (9.5 m) long. While mostly found in saltwater oceans, some dolphin species live in rivers, while others are kept in captivity and trained to perform tricks. Sleek and playful, the dolphin can reach speeds of over 18 miles an hour and are known to enjoy leaping out of the water and playing in the wake of a passing boat.
A dolphin’s diet typically consists of a variety of fish, squid, shrimp, jellyfish, and octopuses. Their diet also depends on the species of the dolphin (there are more than 40 species of dolphin), where the dolphin lives, and the other wildlife that lives around them.
The life expectancy of a dolphin is affected by their habitat, geography, diet, level of endangerment, health, social structure, and species. Dolphins are able to live for an average of 20 years, and female dolphins tend live longer than males. Dolphins that live in captivity tend to have shorter lifespans than those in the wild.
Dolphins are able to live in all of the world’s oceans and in some rivers. Not all species of dolphins are able to live in every environment, except for the bottlenose dolphin who is able to live in almost every ocean except for the Arctic and Antarctic ocean. Most dolphins prefer tropical and temperate waters since they are warm-blooded mammals.