Moon fish - Rare and precious fish in Vietnam Red Book

Moon fish or sun fish, scientific name is Mola Mola, fish of the Moonfish family, in puffer fish. This is a large marine fish with vivid colors and short stems that live outside the ocean, often diving under deep waters, where temperatures are very low.

Biological characteristics

General characteristics of fish are strange fish, they have round oval body, mainly distributed in the tropics, their flat catfish, short tail, round head, large eyes, small mouth, good mouth small compared to full body size, two short fins. Most of the time the sun fish let the bulk of the body float freely to follow the currents. Adults like to drift sideways.

Body shape

Moon fish have a round oval body, very flat, the length of the body can reach from 3.5 to 5.5m, weighs 1400kg to 1700kg, but looks far away, the body is short, looks almost like oval or circle, seen from a distance, looks like a big head. Although the body is large but with a limp body structure, the moon fish swim weakly.

Moon Fish.

Dorsal and anal fin are short but very high, located near the end of the body and almost symmetrical. (above and below). Pectoral fins (small breasts), round, caudal fin low but long, surrounding the rear of the body, looking like a narrow band with little swimming effect. The outer edge of the fins is only slightly wavy. Fish skin is rough, thin, not covered in scales and has no lateral but rough and tough sides, the upper body is gray or brown, and the color is lighter.

Fish moon does not have a real head. Fish face and small gill slit, especially very small fish mouth. Although they are big, their mouths are very small, each has two teeth together to form a mine. With such a special mouth, they could not swallow big lures but only eat small crustaceans and other plankton. The main food of fish is seaweed, aquatic samples, planktonic crustaceans, eel larvae etc

Although the body is large but with a limp body structure, the moon fish swim weakly; most of the time, they only let the mass of their bodies float freely according to the currents . Adults like to drift sideways. Sometimes ocean currents take them from the tropics to the temperate regions. Because of this characteristic, the moon fish is also named "sunfish / sunfish" because it is believed that they "sunbathe" on the sea surface because they often swim lumbering.

Moon fish swim weakly, most of the time they only let their massive body float freely following the water.

Special structure

Because moon fish are in deep water, low temperatures here can affect the neurological and visual functions of fish, so some groups of fish have evolved independently with the ability to warm their eyes. and the brain to limit the effect, some studies show that muscle tissue behind the moon's ankle usually has a temperature higher than 2.1 degrees Celsius compared to normal muscle tissue - but some In the case of up to 6 degrees Celsius, it shows that the moon fish have evolved a number of functions that allow it to produce heat and prevent it from leaking to the surrounding cold water environment. This special function is called "skull endothermy" (cranial endothermy) by scientists .

The base of the diaphragm of the fish is said to be the source of heat. This muscle is the largest muscle, located next to the brain and optic nerve and a thin layer of bone from the brain. The diaphragm stem is reddish and is where many citrate fusion occurs, giving rise to calorific value, compared to all other external muscles. The muscles of the fish are encased in a thin layer of fat to insulate the cold water in the gills, and an inner vein net creates a "heat conductor - transducer" that people think helps the Moon fish. maintain high temperature in the skull.

Moon fish is one of the fish that spawns the most eggs in ocean fishes.

Reproduction

Moon fish is one of the fish that spawns the most eggs in ocean fishes. Although the moon fish is only 3 weeks pregnant, it can produce about 300 million eggs at a time. The eggs of this fish float along the ocean currents. When they were young, they would swim normally like other fish, until they grew up, they started to be lazy just like drifting along the ocean currents.

Distribution

This species is widely distributed all over the world , in the tropics and warm waters, but the moonfish is distributed mainly in tropical waters. In the hot season can come temperate, even to the tropical region, when there is warm weather they come in temperate regions, north and south of the equator. The days of good weather and less turbulence they often emerge to expose part of the body and dorsal surface to catch zooplankton. When there is heavy rain, high winds or chasing prey, they flip horizontally in the water using the dorsal and anal fins by very quickly.

Most of the moon fish life lives away from the mainland.

Most of the moon fish life lives away from the land, moon fish as young people swim normally like other fish, until adulthood, they just like to drift along the ocean currents. The little ones gather together, but when they are big, they just like to live alone, traveling around the oceans.

Moon fish rarely appear in Vietnamese waters, moon fish are recorded in the Gulf of Tonkin (Bach Long Vi). For the first time, the fish has a strange shape and color, the fishermen have been kicked under the ship compartment and transported to the mainland. The largest moon fish during this time was captured up to 400kg. In Vietnam, moon fish is a rare and precious fish, named in the red book and a species that needs urgent protection, completely banning fishing and exploitation activities in any form.