Otter is a mammal that lives in reservoirs and on the banks of rivers, lakes and seas. They have a long body, short legs and thick fur that protects them from the cold in the water. Otters are predators and feed on fish, crustaceans, mollusks and other aquatic animals. They also know how to use stones to open crayfish and shellfish. Otters are very agile and fast in the water, and can also dive to great depths and hold their breath for a long time.
