The world’s largest ocean animal is the blue whale (Balaenoptera musculus). Blue whales are truly enormous creatures, known for their colossal size. They are considered the largest animal ever known to have existed on Earth. Adult blue whales can reach lengths of up to 98 feet (30 meters) and weigh around 150,000 to 200,000 pounds (70,000 to 90,000 kilograms). These magnificent marine mammals have long, slender bodies and are characterized by their bluish-gray coloration and mottled appearance. Blue whales are filter feeders, consuming massive amounts of small shrimp-like animals called krill by engulfing large quantities of water and filtering out the krill using baleen plates in their mouths. Despite their enormous size, blue whales primarily feed on tiny prey, relying on the abundance of krill in the ocean for sustenance.