The ocean is full of mysteries and mysteries. The inhabitants of the depths are very diverse and differ from each other. One of the unusual inhabitants is a predatory sword fish. Swordfish (Swordfish) belongs to the species of ray-finned fish, detachment — perciformes. This is a fairly large inhabitant that can move very quickly.
Origin of the species and description
Photo: Swordfish
This species was first described in 1758 by the Swedish naturalist and physician Carl Linnaeus. The work was presented in one of the volumes of the book “The System of Nature”. The name of this species comes from the Latin “gladius” — “sword”, and the naming of the genus from lat. “Xiphias” — “a short sword sharpened on both sides.” To date, the name of the species has not changed. This is the only representative of the swordfish family.
The naming of the predator indicates its unusual appearance: the long outgrowth of the bones of the upper jaw in structure and size resembles a real weapon, like a sword, which is almost a third of the length of the fish itself. This jaw is called the rostrum. Biologists say that thanks to him, swordfish stun their prey, breaking into schools of mackerel and tuna. The fish itself does not suffer from such actions, since at the base of its “sword” there are fatty shock absorbers that soften the force of impact.
Video: Swordfish
Sometimes the sword-bearer also attacks ships. This behavior is not explained in science. Sometimes this is explained by the swordfish mistaking the ship for its enemy (for example, a whale).
Interesting fact: In 2015, a swordfish stabbed a man who harpooned her in the chest. This led to the death of the underwater hunter.
Swordfish is a valuable commercial fish. Its world catches exceed 100 thousand tons per year. The swordtail makes long migrations.
Appearance and Features
Photo: Swordfish
Swordfish is a large inhabitant of the ocean. Body size usually reaches 3 meters, and some grow to a length of almost 5 meters. The weight of an adult is from 300 to 550 kg. By its appearance, the predator resembles a powerful deadly weapon (hence the name of the species). The main difference from other inhabitants of the ocean is the long outgrowth of the upper jaw, which resembles a sword. It is 1/3 the length of the entire body.
The fish has an oblong snout with maxillary claws, and under it a dense fatty layer is hidden. It will not be difficult for an inhabitant to break through, for example, metal 2-3 cm thick, without even getting injured! The swordfish has a fairly wide mouth. Only young fish have teeth. Over time, the predator loses them. In babies (individuals up to 1 m.) There are small spikes on the body. Young predators acquire stripes on the body, which also disappear over time. The swordfish does not have scales, but it has a very developed and streamlined body. The tail has a semi-lunar shape.
The color of these individuals is most often brown with a dark blue tint. Blue eyes. This inhabitant does not have ventral fins, but there are dorsal, lateral and pectoral fins, delimited into 2 parts. A high black triangular front fin originates from the back of the head, and the rear one is located near the tail.
Interesting fact: The structure of the body allows you to reach speeds of up to 130 km/h! Ichthyologists say that such a huge speed of overcoming the water column violates all known laws of physics!
The average life of a swordsman is 10 years. Females live longer than males and are larger.
Where do swordfish live?
Photo: Beautiful swordfish
Swordfish love warm climates. Sometimes she swims under the rays of the sun and ventilates the fin, which is located on the dorsal part. Most often, the predator is found in the Atlantic, Indian and Pacific oceans, that is, these are tropical and subtropical waters, where the active time for food production takes place.
These individuals have a period of migration, when they move their place of residence to another water. Usually they swim in temperate latitudes: the Mediterranean, Marmara, Black, Azov Sea. In the colder part, they can also be found, for example, they are found in the North Sea. In summer, the fish swims into cold waters, and then returns with a change in habitat temperature.
Favorable water for existence is 12-15 degrees (reproduction occurs at 23 degrees). Fry and eggs survive at 24 degrees. The swordfish lives at a depth of 800 meters, if necessary, it can go down to 2800 m. During the day, the swordtail prefers spending time in the water column, and at night it is near the surface. The average speed of movement of swordfish is about 34 km per day.
The fish does not gather in flocks or shoals, but prefers to be alone. Pairs are formed only during periods of active reproduction. The distance between the inhabitants of this species is from 10 to 100 m from each other. The individual does not live off the coast. Swordfish do not live in the Arctic latitudes. Fishermen have witnessed swordfish jumping out of the water. This means that the fish is getting rid of the parasites that are infested on their body.
What do swordfish eat?
Photo: Swordfish
The swordfish is an opportunistic predator and a powerful hunter. The diet is huge (other fish, shellfish, plankton, etc.). The fry of the swordtail already have several small teeth and a thin snout. They feed on commonly found plankton and grow rapidly. This is how the gradual transformation into an adult takes place.
In pursuit of its prey, the swordsman develops a speed of up to 140 km/h. Thanks to the near-eye organ, a predator can see and capture its prey in the thickness of the ocean waters. Hiding from a predator is almost impossible! Based on the fact that the fish dives into the water to a depth of 800 m, and also moves on the surface, between open waters and coastal areas, it feeds on both large and small organisms. In a word, the swordsman eats absolutely everyone who meets on her way. It is able to cope even with a predator (like a shark).
To a greater extent, the diet consists of:
- squid;
- mackerel;
- herring;
- mackerel;
- tuna;
- sea bass;
- crustaceans;
- anchovy ;
- hake
Sometimes a swordfish, having found a prey, can stun it with a “sword”. The researchers found that in the stomach of this individual there are squids, fish that are cut into pieces or damaged by the “sword”. In addition, a predator is able to swallow its prey whole.
An interesting fact: swordfish can even attack whales! Such behavior has not yet been explained by scientists, since this individual does not eat whale meat.
Peculiarities of character and lifestyle
Photo: Swordfish
The swordfish has its own characteristics:
- great speed movement;
- special structure of the gills;
- unusual body temperature;
- attacking ships (ships).
Swordfish is considered the fastest individual in the ocean, which carries a weapon in the form of a sharp sword. This characterizes it as a dangerous and predatory fish, which is better not to catch the eye! Fish also have a special gill structure. They perform not only the function of breathing, but also a jet-type engine. For example, when a fish moves quickly, water passes in an endless stream through the gills and is ejected with the help of them under pressure. At the same time, the swordfish constricts and expands the gills, which helps control the speed of the water flow.
Another feature is the unique body temperature. It is almost a dozen and a half degrees higher than the temperature of the water in which the fish lives. A special property is the fact that the swordsman has a near-eye organ that warms the blood. This allows the fish to be almost unnoticed in the depths of the ocean, as blood flows to the brain stem and eyes.
Such features allow the swordfish to be constantly in motion and active. She is always ready for a lightning-fast throw and capture of the victim, and also quickly dodges her enemies. The swordsman has a habit of attacking boats or large ships. Since the fish has a huge movement speed, this gives it great power to strike. The sword pierces metal sheathing and thick oak planks. Under such conditions, the fish itself does not receive blows.
But there is another danger for it: sometimes it happens that the sword gets stuck in the bottom of the vessel, and it cannot be pulled out or broken off. Unfortunately, after this, the swordsman dies. For fishermen, this is a valuable prey.
Social Structure and Reproduction
Photo: Sea fish sword
Swordfish prefer to hunt and move individually rather than in groups. Each predator acts independently of its neighbors. Groupings of pairs can be observed only during the breeding season. At such times, individuals usually approach the shores for the spawning process. Favorable water temperature for breeding is 24 degrees, but not lower. Caviar reaches large sizes (up to 1.8 mm) and has a significant fatty subshell.
Hatched fish have peculiar rough scales and prickly spines arranged in a row. The fins are not yet separated, but are continuous. The fry initially live on the surface of the water, not falling below 3 meters. Further, with growth, the development and change in the activity of predators occurs. The sword grows when the fish has reached a length of 8 mm, and already with a length of 1 cm, the swordsman can hunt fry of other fish. By the first year of life, the predator has a length of up to 60 cm.
The process of turning a larva into an adult proceeds smoothly, without sudden changes. A fish 1 meter long acquires all the signs of an adult. At the age of 3, most young swordfish move to the border waters of tropical latitudes, where they continue to intensively feed, grow and develop.
Puberty occurs upon reaching a body length of 140-170 cm (this is approximately 5 or 6 years). The fecundity of swordfish is high. The larger the female, the more she spawns. For example, a female weighing 65 kg can produce about 15 million eggs.
Natural enemies of the swordfish
Photo: Swordfish
The swordfish has a frightening and formidable appearance. With her behavior, she is able to scare away many inhabitants of the ocean. Despite this, the swordsman has natural enemies. One of them is a killer whale. This mammal will attack swordfish, but adults, thanks to their gigantic physique, give a sharp rebuff to killer whales. Another of the enemies was the mako shark or the blue-gray shark. She often hunts young swordtails that have not yet learned how to defend themselves. Adult representatives fight the shark to the last, until the enemy dies from a smashing sword.
The main enemy of the swordfish (and of all animals and fish) is a man. Fish suffer from pelagic longline fishing. There is also sport fishing, where trapping takes place by trolling. This fish has been caught since ancient times for delicacy meat. It is very tasty and expensive, does not have a “river” flavor and small bones.
Depending on how and what the fish ate, the meat can be red, orange (if shrimp dominated the diet) or white. The most popular is white fillet, which is considered more refined and of higher quality. Scientists do not worry about the activity of obtaining swordtail meat, as they have good fertility.
An important fact: swordtail meat is contraindicated for pregnant women and young children, as it is considered toxic due to the predominance of organometallic cations in it. .
Population and species status
Photo: Swordfish
Scientists conducted studies and calculated that almost 40% of marine inhabitants are on the verge of exhaustion. If no attempts are made to reduce the catch, then by 2050 the figure may approach or even increase to 90%. The problem boils down to the fact that when fish and shellfish disappear, large individuals also die. Fishing is not only an official fishery, but also amateur fishing, and, worst of all, poaching.
Currently, news about the illegal catching of valuable fish — swordsman. For this purpose, deep-water networks or special drifter networks are used. The well-known Greenpeace organization 10 years ago put the swordfish on the red list of seafood that are on store shelves in huge volumes, which is the result of overfishing.
The swordfish (Swordfish) has a special structure and appearance, which turns her into an enemy or into reliable self-defense. The struggle with unlimited fishing of this fish continues, but so far its population is still large, thanks to fertilization. The fish is both predator and prey for other inhabitants of the ocean (sharks and killer whales), as well as food for humans. It is always worth remembering that the planet’s reserves are in limited quantities. It is necessary not only to consume, but also to protect and protect what surrounds us.
