Characteristics Soft, fluffy fur, cute little paws, adorable face. All of these are characteristics of the adored Sea Otter! Learn some fast facts down below View fullsize Sea Otter Facts ~ 4 ft. ~ 50-100 pounds ~ Average life span: 23 years ~ Scientific name: Enhydra Iutris View fullsize Sea Otters have water repellent fur that keeps them warm and dry, but for it to work it needs to be clean. Sea Otters clean their own fur so this effect works. View fullsize Sea Otters have webbed feet to help them swim! View fullsize When Sea Otters swim underwater, their ears and nose close up. View fullsize When Sea Otters are resting in a group it's called a raft. View fullsize Sea Otters have the thickest fur of any animal. They can have between 600,000-1,000,000 hairs per square inch!