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Interesting Facts About Swordfish You Probably Didn't Know

Interesting Facts About Swordfish You Probably Didn't Know
The swordfish uses its remarkable bill to attack its prey and defend itself. Are you hungry for some more cool facts about this amazing fish? AnimalSake will give you a lot of interesting information about the swordfish, such as its diet, appearance, habitat, and much more.
Akshay Chavan
Last Updated: Aug 12, 2017
Did You Know?
The swordfish is one of the largest fish in the ocean, besides being among the top ten fastest ones around.
The swordfish is a large, marine fish, that is famous for its long sword-like bill. It is also known by other names, like the broadbill and the broadbill swordfish. In the scientific community, it is known as Xiphias gladius, in which the Latin word 'gladius' means sword. This fish belongs to a category of fish known as billfish, which also contains fish like sailfish and marlins, all of which have an elongated jaw or bill. The swordfish is the only surviving member of the fish family Xiphiidae.

Though the swordfish is highly migratory, it can also be found near the shores. It is commonly confused with another famous billfish, the marlin, and sometimes also with the sailfish, though there are major differences between them. The bill of the swordfish is longer and stronger than the other two. It is also much flatter. An important difference is that its dorsal fin is much smaller, and adults completely lack scales or teeth. Besides, the sailfish is the fastest fish in the ocean.

The swordfish's unique way of catching its prey, coupled with its fighting spirit, makes it a prized catch among fishermen. Its enormous size makes it ideal for steak and barbecues. A variety of recreational sports thrive on the difficulty and challenge of catching this elusive fish. Many more interesting facts about the swordfish are listed in the sections that follow.
Interesting Swordfish Facts
This is a large fish, on average about 5 to 8 feet in length, though individuals may grow to be 14 feet long. Its weight usually ranges between 150 to 250 lbs, but some may even be as high as 1,000 lbs. The heaviest swordfish on record, captured in Chile in 1953, weighed 1,182 lbs.
Females are much larger than the males.
male and female swordfish
Its upper jaw grows long and flat like a sword, giving it its famous name. When fully grown, the bill accounts for one-third for the swordfish's total length. It is used for defense and catching prey.
It is brownish to blueish-gray in color on the top, the sides, and fins. Its underbelly is off-white in color. This helps it to blend in its surroundings, both, when viewed from above or from below.
The fish has two dorsal (on the back) fins, with the front one being much larger than the one at the back. It has a pair of large pectoral (in chest region) fins and two pelvic fins, with one large and the other very small. The tail fin, called the caudal fin, is crescent-shaped.
There are several differences between juveniles and adults. Juveniles have teeth and scales, while the adults don't. Juveniles have equally-sized jaws with teeth, and with age, the upper jaw elongates into the bill. The lateral line―the line running lengthwise in the middle on the sides―is present in young fish, but not in adults.
It is found in both shallow water and water as deep as 650 meters.
It prefers warmer water in the range of 64 and 72º F, though it can tolerate a temperature between 41 to 81º F.
The swordfish is found in the Indian, Atlantic, and Pacific oceans, and even in some cold regions like the Mediterranean sea, the Sea of Marmara, the Black Sea, and the Sea of Azov. The majority of them are found in the Pacific ocean.
It is highly carnivorous, and feeds on a variety of fish and invertebrates, mostly at night.
They prefer fish like rockfish, barracuda, mackerel, menhaden, silver hake, bluefish, herring, tuna, butter fish, sand lance, gadids, scombrids, and lanternfish.
Among invertebrates, they prey on squids and octopuses.
They can move as fast as 50 mph in sudden bursts, making them one of the top ten fastest fish in the ocean.
While feeding, it uses its bill to separate prey from a shoal of fish, by injuring it. It then swallows it whole.
For larger prey, it slashes them into pieces by moving its head from side to side. The sword also makes it easier for them to swim through water.
Contrary to popular belief, swordfish don't pierce or use their bills like a spear. This will not allow them to reach a prey stuck at the tip of its bill. Rather, they simply make slashing movements.
It uses its bill to protect itself from killer whales, sperm whales, and sharks, which are some of the few predators that prey on them. In fact, mako sharks have been found dead with the bill of a swordfish lodged in their heads, which indicates the dangers of attacking a swordfish.
The body consists mostly of white muscle fibers, which are not built for endurance. Rather than swimming long distances, it allows the current to carry it everywhere.
Being highly migratory, it migrates from cold water to warmer water in the winters. However, in the summers, it may migrate to cooler regions to lay eggs.
Swordfish move alone, rather than in a shoal. At the most, they may move at a distance of 10 meters from another swordfish.
They are strong and aggressive fighters. In some cases, after being caught in a fishing line, they have pierced through the hull of the boat with their bills. Even more shockingly, when hurt by fishermen, some fish will dive so fast, that they plunge their beaks deep into the sea bottom right up to their eyes.
The swordfish has an interesting adaptation called the 'brain heater', which increases the blood flow to its brain and eyes to warm them up. This enables it to see much better in cold water; an ability which is possessed only by 22 among 25,000 fish species!
Swordfish Leaping Out
Swordfish Leaping Out
Its famous habit of leaping high out of the water is thought to remove parasite fish like lampreys from its body.
The swordfish basks in the sun with its first dorsal fin above the water, which makes for an attractive sight.
Swordfish become sexually active at the age of 5 to 6 years
While mating, fertilization is external. This means that the female ejects her eggs into the water, which are then fertilized by a secretion of sperms by the male.
Females can carry as many as 1 to 29 million eggs inside them. Larger females carry more eggs than smaller ones.
Juvenile swordfish are preyed on by several aquatic animals, including adult swordfish in times of food scarcity.
A swordfish may live as long as 15 years, though the average lifespan is around 9 to 10 years.
The swordfish is currently considered as a species of 'Least Concern' on the IUCN's Red List. This means that it is not endangered.
In 1998, dwindling swordfish populations prompted the US government to ban swordfish fishing in parts of the Atlantic. This has led to a resurgence in its population in the North Atlantic, though overfishing is still a concern in the Indian ocean.
It is a popular food source in countries like Japan, Spain, USA, Mexico, and Australia, with Japan accounting for one-fourth of the world's total catch.
Swordfish on Display in a Market
Swordfish on Display in a Market
'Swordfishing' is a recreational fishing game, which has gained popularity due to the fish's reputation of vigorously fighting back.
Its categorized as an 'oily' fish, which increases the risk of toxic chemicals like methyl mercury accumulating in its body. This is why pregnant women and children are commonly advised not to consume it.
While its long sword and large size may give the swordfish a formidable appearance, evidence suggests that it has never attacked humans without provocation.