Photo: A blue marlin leaps from the water

The blue marlin, one of the largest and most beautiful fish in the ocean, spends most of its life far out at sea.

Photograph by Tony Arruza/Corbis

Map

Map: Blue marlin range

Blue Marlin Range

Fast Facts

Type:
Fish
Diet:
Carnivore
Average life span in the wild:
Up to 27 years (female)
Size:
Up to 14 ft (4.3 m)
Weight:
Up to 1,985 lbs (900 kg)
Group name:
School
Did you know?
It is a blue marlin that the fisherman battles in Ernest Hemingway's classic novella The Old Man and the Sea.
Size relative to a 6-ft (2-m) man:
Illustration: Blue marlin compared with adult man

The strikingly beautiful blue marlin is the largest of the Atlantic marlins and one of the biggest fish in the world. Females, which are significantly larger than males, can reach 14 feet (4.3 meters) in length and weigh more than 1,985 pounds (900 kilograms). Average sizes tend to be in the range of 11 feet (3.4 meters) and 200 to 400 pounds (91 to 181 kilograms).

Native to the tropical and temperate waters of the Atlantic, Pacific, and Indian Oceans, blue marlins are among the most recognizable of all fish. They are cobalt-blue on top and silvery-white below, with a pronounced dorsal fin and a long, lethal, spear-shaped upper jaw.

They are so-called blue-water fish, spending most of their lives far out at sea. They are also highly migratory, and will follow warm ocean currents for hundreds and even thousands of miles.

Blue marlins prefer the higher temperature of surface waters, feeding on mackerel and tuna, but will also dive deep to eat squid. They are among the fastest fish in the ocean, and use their spears to slash through dense schools, returning to eat their stunned and wounded victims.

Known for putting up a tremendous fight when hooked, these rare marine monsters are the holy grail for sport fishers. Their meat is considered a delicacy, particularly in Japan, where it is served raw as sashimi. Although not currently endangered, conservationists worry that they are being unsustainably fished, particularly in the Atlantic.

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