Swordfish

Swordfish (Xiphias gladius) are large, highly migratory, predatory fish characterized by a long, flat bill. They are a popular sport fish, though elusive. are elongated, round-bodied, and lose all teeth and scales by adulthood. They reach a maximum size of 14.75 ft (4.3 m) and 3,190 lb (1,446kg). The International Game Fish Association's all-tackle angling record for a was a 3,183 lb (1,443 kg) specimen taken off Chile in 1953.

They are the sole member of their family Xiphiidae.

The is also known as The Gladiator (gladius) because of the sharp, sword-like bill it possesses as an addition to its streamlined physique, alowing it to cut through the water with great ease and agility. Contrary to belief the "sword" is not used to spear, but instead may be used to slash at its prey in order to injure the prey animal, to make for an easier catch. Mainly the relies on its great speed and agility in the water to catch its prey. One possible defensive use for the sword-like bill is for protection from its few natural predators. The shortfin mako shark is one of the rare sea creatures big enough and fast enough to chase down and kill an adult swordfish, but they don't always win. Sometimes in the struggle with a shark a can kill it by ramming it in the gills or belly.

Females grow larger than males, with males over 300 lb (135 kg) being rare. Females mature at 4-5 years of age in northwest Pacific while males mature first at about 3 to 4   years. In the North Pacific, batch spawning occurs in water warmer than 24 °C from March to July and year round in the equatorial Pacific. Adult forage includes pelagic fish including small tuna, dorado, barracuda, flying fish, mackerel, as well as benthic species of hake and rockfish. Squid are important when available. likely have few predators as adults although juveniles are vulnerable to predation by large pelagic fish.

While are cold-blooded animals, they have special organs next to their eyes to heat their eyes and also their brain. Temperatures of 10 to 15 C° above the surrounding water temperature have been measured. The heating of the eyes greatly improves the vision, and subsequently improves their ability to catch prey. Out of the 25 000+ species of bony fish, only about 22 are known to have the ability to heat selected body parts above the temperature of the surrounding water. These include the swordfish, marlin, tuna and some sharks.