what do sea otters eat

Sea otters primarily eat marine invertebrates such as sea urchins, crabs, clams, mussels, snails, abalones, and sometimes slow-moving fish. They use rocks as tools to crack open the shells of their prey. Sea otters consume about 25 to 30 percent of their body weight daily to maintain their high metabolism and stay warm in cold ocean waters. Their diet helps control populations of sea urchins, which in turn protects kelp forests, making sea otters a keystone species in their ecosystem