Otters sometimes use tools to hunt and catch their prey.
Picture from Archies
An otter will sometimes use rocks to smash open clams, mussels, or other small shellfish. They also will sometimes dive up to 330 feet to find their prey. Adult sea otters can eat 25 to 30 percent of their body weight per day in order to stay warm. Feeding is a very important activity for sea otters, and occurs mainly in the morning and afternoon.