Shortfin Mako sharks are really fast fish, some scientists say they are the fastest fish in the ocean. They normally swim at 30-35 miles per hour, but can swim up to 50 miles per hour. They even look fast, torpedo shaped body, short fins, and strong tail. They can't help being fast. These sharks grow up to 13 feet long and have 4-25 pups. These sharks feed mostly on oceanic fish, including other sharks, large marine mammals, and invertebrates. These sharks have attacked humans, but only if they feel threatened by humans in their habitat.