The blue marlin is a large species of fish found in tropical and subtropical oceans around the world. Known for its striking blue color and long, pointed bill, it can grow up to 14 feet in length and weigh over 1,800 pounds. Blue marlins are highly sought after by sport fishermen due to their size and fighting ability. These fish are part of the Istiophoridae family, which also includes other billfish like the swordfish and black marlin. Blue marlins primarily feed on smaller fish, such as tuna and sardines, and are known for their speed and agility in the water.