The swordfish, also known as the green swordfish. Because its upper jaw extends forward in the shape of a sword, so the name. Belongs to the class of fish, perch order, swordfish family of a flying fish. Distributed in the Indian Ocean, the Atlantic Ocean and the Pacific Ocean, the western Atlantic coast of the Americas is the main origin of the swordfish. In China, swordfish activities in the East China Sea, Taiwan Strait to the South China Sea, the vast outer sea, fishermen in these waters are caught.
Swordfish young fish, meat is delicious, and can be salted into dry, long-term preservation. It can also be processed into canned food, fish sausage, fish ham and so on. These fish are rich in fat and contain a lot of vitamin A and so on. Due to the large individual size and high economic value of this fish, it occupies an important position in the fishing industry, and its production is rising.
Interesting Habits: The upper jaw of the swordfish is sharp and long, like a sharp sword, reaching straight forward. Its body is prismatic, back dark brown, belly silver gray, 4-5 meters long, the longest up to 6 meters, weighing about 300 kilograms, one of the large and ferocious fish. Swordfish is often active in the upper and middle water layers, swimming, often the head and dorsal fins out of the water, with the sword-like upper jaw splitting the water forward, the speed is very fast, up to 119 kilometers per hour, for the general train speed of about twice. It can also dive into the water at a depth of 500-800 meters, chasing fish and other aquatic animals. Predation, fierce impact on the fish, with the "sword" stabbing, and then swallowed. Although the swordfish is fierce, it is timid and fearful, and often avoids other large fish. However, once enraged, they charge at large fish or ships. It is said that in a foreign coastal museum, there is still displayed a small boat board, which contains the broken jawbone of the swordfish. Fish body length of 3-4 meters, the whole body steel blue, lusterless, with small white spots; head like swordfish, but shorter, conical; dorsal fins waving like a flag. Swordfish to fish for food, sexual ferocity, the king of the sea -- whale is also often its defeat. In pursuit of fish, the dorsal fin collection in the longitudinal groove of the back, so the swimming speed is very high, up to more than 100 kilometers per hour, second only to the sailfish, when it needs to reduce the speed of the flag will be unfurled to increase the resistance. When exposed to the surface, it looks like a fishing boat sails, so it is also known as the "sailfish".
Breeding habits
Adults are up to 5 meters long and weigh more than 400 kilograms. The age and growth of the swordfish are unknown. The smallest individual in the reproductive population is 1.39 meters in length and 0.5-2.8 meters in body length (eye to tail fork). Fish less than 1.3 m in length are immature individuals, and the average annual growth in body length for western Pacific swordfish has been calculated to be 25 cm. The sex ratio of males to females is roughly equal. Spawning occurs almost all year round, mainly from March to July in the Northern Hemisphere and January in the Southern Hemisphere. Wrasse lay floating eggs, 1.63-1.68 mm in diameter, single oil globules, 0.40 mm in diameter. At water temperatures of 22.5-25.2°C, oviposition takes place in about 70 hours, and the first eggs are 4.0 mm long. About 7-8 days and nights after the egg canon all absorbed. It feeds actively on small zooplankton, and pursues zooplankton and other fish vertebrates when its body length exceeds 100 millimeters, while adults feed on pelagic fish such as mackerel, jawed needlefish, and cephalopods, as well as deep-sea fishes such as cod, turbot flounder, and lantern fish.
Edit Appearance
The body is up to 3 meters long, with a mass of up to 900 kilograms, and the upper jaw protrudes like a sword. The muzzle is long and arrow-like, the body is stout and fusiform, and the dorsal and ventral surfaces are bluntly rounded. The caudal peduncle is thick and strong, flat, with a well-developed bulge on each side. Head large. The muzzle consists of the premaxilla and snout bone, extending forward, arrow-like, flattened, the eyes large, superiorly lateral, the interocular intervals broad and flat. Oral fissures large, mandibles short. Adults are edentulous (juveniles have fine teeth), with no teeth on the jawbone and tongue. Margins of anterior gill cover bones not serrated (juveniles dentate). Adult skin bare, scale-free epidermis rough, lateral line inconspicuous, two dorsal fins. The first dorsal fin is high in front, triangular and sail-shaped, and the fins after the 14th fin are very short and are contained in the dorsal groove, not exposed. The second dorsal fin is short and low, located on the caudal peduncle, and there are two anal fins, the first anal fin is larger and located at the back of the body, and the second anal is isomorphic to the second dorsal fin. The head and dorsum of the body are bluish-purple, the abdomen blackish, without markings. Each fin is dark blue with a silvery glow.
The body color of the green swordfish, with a bluish-purple head and dorsal part of the body and a blackish belly, is often referred to as the green swordfish. It is a large pelagic migratory fish, body length is usually between - meters, large up to meters; weight is usually - kilograms, some up to kilograms.
The body of the green swordfish is stout and extended backward, with a bluntly rounded dorsal-ventral region and an elongated, flat tail. The upper jaw consists of the maxilla and the nasal bone, and extends forward to form a sword-like muzzle, hard and extremely sharp. The eyes and mouth are large, and both jaws are dentate in juveniles, but toothless in adults. The fish is naked, with rough skin and obscure lateral lines. The dorsal fins are separate. The first dorsal fin is shaped like a triangular sail, and the second dorsal fin is short, homomorphic with the anal fin, and is positioned opposite to the anal fin. It has no ventral fin, and the caudal fin is y forked.
Habitat
The green swordfish lives in the upper layers of the tropical and subtropical oceans, and is an exceptionally fierce fish that feeds on fish and cephalopods, such as shrimp and gun squid, and has its reproductive season in the month of January each year. Swordfish swimming ability is extremely strong, extremely fast, up to 119 kilometers per hour, is one of the fastest swimming fish, it is generally migrating in the water surface layer, sometimes exposed dorsal fins, and sometimes leaping out of the water, this kind of fish swimming is not a group, each fish to maintain at least within the distance of meters. The arrow-like long muzzle is the main weapon of swordfish attack and predation, it flies out of the sea with great explosive power, often rushing out of the sea to attack large cetaceans and fish with the sword-like upper jaw, it is said that the green swordfish has also attacked the ship, resulting in the sinking of the ship. The swordfish is also a high value economic fish with bright red meat and liver rich in vitamins. It is caught by fishermen in Taiwan with dart guns and by fishermen in the Xisha Islands in the South China Sea with longlines.