The animal known for being the fastest swimmer is the black marlin. This species of billfish can reach speeds of up to 82 miles per hour (about 132 kilometers per hour), making it one of the fastest marine creatures. Native to warm ocean waters, black marlins are known for their powerful bodies and long, slender fins, which enable them to navigate through the water with agility and speed. Their impressive swimming abilities are essential for hunting prey, such as smaller fish and squid, as well as evading predators. Their remarkable speed and strength make black marlins a favored target for sport fishing.