The species that is confused with the marlin fish, with the emerald fish and with other species is the swordfish, one of the most stylized fishes that have been described. In this post some characteristics will be explained, as well as their diet, reproduction, habitat and finally the dangers that make it considered a threatened species.
Swordfish
The swordfish is also known as palá needle in Spain - Andalusia and "albacore" in Chile, this species has the scientific name Xiphias gladius and belongs to the family Xiphiidae of order perciformes, which is part of the class ACtinopterygii, wire Chordata of the kingdom animals, which is one of the five kingdoms of living beings that group in different taxonomic classifications all organisms that have life, whether marine, terrestrial or aquatic.
Another way of referring to the swordfish is "the gladiator", this name refers to the shape of its body, especially its sword, since the term gladius means sword in its translation from Latin. It is also confused with the emperor fish, which is a quite different species of scientific name. Luvarus imperialis. This occurs not because of similar physical characteristics but because of the appearance and flavor of their meat.
Habitat
This is a species that can be found in all the oceans of the planet, even so, they seem to prefer temperate waters, an example would be the Black Sea and the Mediterranean Sea, which is where they have been seen most frequently. In addition to the areas mentioned, they also prefer those that are tropical, subtropical or temperate, such as the Atlantic, Pacific and Indian Oceans.
They usually make migrations to move from warm waters to colder waters, because they feed on those where the temperature is lower. They keep swimming at depths ranging from 500 to 800 meters during the day, as night falls they rise to the surface and jump out of the water. These jumps have been confused with other species such as the Marlin fish.
Several specimens of swordfish have been seen on the coasts of North America, specifically in Mexico and the United States, in eastern Japan and in the western Pacific they abound. There is a certain amount of swordfish in the North Atlantic, these are in danger of extinction.
Features
Some characteristics will be explained below, the first ones correspond to physical aspects of the swordfish and the others are general data about the species, to then talk about the feeding and reproduction of these large aquatic animals.
- The colors that are most common in this species are blue or black, it is in the part of the belly where they show a silver color but the rest of their body has one of the first two colors.
- What has the appearance of a sword is the fusion of the bones of the upper jaw that are developed and prolonged in this way as they grow. This beak is very useful for attacking predators that threaten prey that are part of their diet.
- On average they measure from two to three meters, but there are specimens that exceed four meters. While the average weight is 120 kilos and can also be exceeded.
- Swordfish can reach a speed of 100 kilometers per hour.
- When they are adult fish they lose their teeth and scales.
- There are several characteristics that have led people to confuse them with other species, for example, the jumps out of the water mentioned above and the meat, the latter because their meat is very similar (in physical appearance) to that of the dogfish.
- Several cases have been described of swordfish that have pretended to be tired or injured when a boat approaches them, and when there is little distance they cross it with their sword causing holes of up to 5 centimeters in diameter, which allows one to get an idea of the thickness of this part of your body.
- Swordfish can be classified as a homeothermic or warm-blooded fish, although they feed in cold waters they need to regulate their body temperature to keep their blood warm (between 10 or 15 C°) regardless of the temperature of the environment in which they live. the one they meet. However, this temperature control is not complete, it is only in your eyes and your brain.
- This ability to keep their eyes temperature controlled allows them to have good vision, especially when they are catching prey. In addition, they share this with more than 25.000 species that have this characteristic as part of their adaptations to the aquatic environment, an example of this is tuna, also sharks, but not all of them, those that belong to the family of lamnids are homeotherms.
Food
They have a fairly aggressive behavior, they are capable of attacking fish that are larger than them. However, their diet is not based on larger species but cephalopod fish, barracuda, molluscs, hake, tuna, mackerel, squid and some types of crustaceans. Their prey really must be smaller, to hunt them they use their beak in the form of a sword with which they hit them so that they are stunned, then they prick them and eat them.
Reproduction
A swordfish can be considered sexually mature when they are between 2 and XNUMX years old, at this time they begin to reproduce and begin to check out the females by swimming around them. This reproductive process takes place in warmer waters than those they prefer to feed on, so they migrate and reproduce there. This occurs between June and September.
Upon fertilization, the females are capable of fertilizing millions of eggs that they lay in successive clutches of eggs. While the males stay close to protect them from other predators looking to eat them, the females also stay close both for the next laying of eggs and for the protection of those that are already there.
After being born, the swordfish can measure only four centimeters, little by little they grow while they stay close to the surface. During this development process, it is seen how their body becomes more stylized and thinner, they reach 12 centimeters when their beak is already considerably developed. First, this part develops very well, the upper part growing first than the lower part, that is, they do so at the same time, but at a different speed.
Then the dorsal fin grows more until little by little it spreads throughout the body of the swordfish, by this point the specimen should measure about 23 centimeters, then the second dorsal fin forms until it is fully developed and the fish measures approximately 52 centimeters. From there it can continue to grow or the measures mentioned can be double or triple until it reaches a large size.
Threats
Swordfish in the aquatic environment do not fight against many predators, only killer whales and some species of sharks, such as the White shark they have it as part of their list of potential prey. The shortfin mako is a species with which the swordfish has fought for its survival to the point of losing its beak, some shortfin mako carcasses have been found with the sword of a swordfish embedded in their skulls.
In addition to those mentioned species they fight with several species that are located in the pelagic zone of the ocean. However, they have been able to defend themselves against them much more successfully than they have at defending themselves against humans. A characteristic of human beings is that they are the most dangerous predators for millions of species of animals, plants and other living beings. Human activity in the sea has affected not only swordfish but other species, bringing them to the brink of extinction.
One of the main actions is excessive fishing, as a commercial and sporting activity, swordfish have been seen as an object of decoration in homes and public places such as restaurants. Swordfish have been hunted that measured almost and a little more than six meters, with a weight that exceeded 600 kilos, a loss for marine fauna and a trophy for its fishermen.
Although the fishing of this species is prohibited, it is still one of the most coveted specimens by humans who practice fishing as a sport, seeking to capture as large a swordfish as possible, in fact, they hold a record in the «International Game Fish Association”, where the records of the largest and heaviest fish caught in the world are recorded. The size and weight of the largest swordfish caught was five meters and 536 kilos (it was in Chile in 1953).
In addition to that, they are hunted for food due to their high nutritional value, according to the fish information sword that is handled all over the world is rich in vitamin A, B1, B2, B3, B5, B6, B9, B12, C, D, E, calcium, copper, phosphorus, iron, zinc, magnesium, sodium, iodine, potassium, among other things.