Pinnipeds = Seal, Sea lion, Fur Seal and Walrus. California Sea Lion is the fastest pinniped with top speed (in short burst) of 24-25 mph. Crabeater Seal is one of the fastest phocid seals, with speed up to 16 mph. Harbor Seal (aka Common Seal) tops 12 mph (in short burst). Harp Seal = 20 mph. Grey Seal = 20 mph (in short burst too). Walrus is the slowest of the pinniped but can reach 20 mph (in short burst). Unlike dolphins and whales, pinniped cannot maintain high speed for a long period.