Biography Skat fish

The slopes of the slopes are not like any other fish. A large, flat, disk -shaped body, unlike flounder, symmetrically. On the sides it is bordered by large thoracic fins and ends with a thin tail stem. The main movement of the slopes is the chest fins. The tail stem is sharply delimited from the body. It should be borne in mind that the body length of the slopes, unlike other fish, is measured without a tail stem.

In the northwestern part of the Sea of ​​Japan, seven types of slopes are known, represented by two families: slopes and slopes-hvostokols. Skates-Khvostokols Dasyatidae family come to us only in the warm season in small quantities. These fish are found both at the bottom and on the surface of the sea. The giant slope of the Dasyatis akajei reaches a length of 2.3 m. The family of slopes-hvostokols is not at all rich in species variety.

The Rajidae Skat family is more diverse - in the world ocean there are several dozen species. There are five of them in the waters of Primorye, and they are all similar to each other. These fish belong to bottom species. However, they are able to rise to the surface. I watched the slopes twice at the very surface of the water in the open sea. Both times in the summer. The first time at night at a light station in the city of many fish, preferring life in the trunk of water, rise at night to the surface of the water after the plankton migrating from the depths.

Plankton is followed by small fish, and behind them are large. The raising of a slope to the surface in the daytime is difficult to explain. I could not establish a species, but the fact that these were not slopes-hvostokols, but representatives of the Skat family, I can say unequivocally. Of the five types of slopes in fishing catches, two types are most often found: Bathyraja Parmifera thyroid slide and Bathyraja Bergi Berg.

These two species are very similar. In the first species, the middle row of spikes along the ridge on the back is continuous or interrupted in the rear of the body. The second has the middle row of spikes, unlike a thyroid ramp, always interrupted. The lower part of the disc is always white. Coloring varies from gray to dark brown. In a thyroid slope, the coloring is still more often gray-brown, and in the ramp of Berg-dark brown.

The widespread thyroid slide is more massive. He lives along the Asian coast from the Bering Sea to the south to the coast of the Japanese archipelago and the Korean peninsula. Near the American coast is found in the Gulf of Alaska. It can fall to almost one and a half kilometer depth. In the spring, he is able to come close to the shore to a depth of 10-20 m. But still, it is common only at the depths from to m.

The thyroid slide reaches the length to cm. According to the power method, it refers to pronounced Bentiophage predators with a fairly wide range of food objects. Simply put, since the thyroid ramp leads a bottom, sedentary lifestyle, it consumes not too mobile bottom fish, crustaceans and mollusks. Spawning is year -round, depending on the time of the year, it takes place in the upper section of the depths of the depths and on the shelf.

These slopes are characterized by pronounced sexual dimorphism. Adult males have large pherigopodia. This is an oviparous look. The egg is enclosed in an elastic, but strong keratin shell. The shape of the egg resembles a small pillow with cords-ultrasounds at the corners. At first, flexible and mobile, these antennae cling to the irregularities of the bottom, who wrap the roasts, playing the role of the anchor.

In general, the egg is well protected, and the survival of the eggs is high. But small slopes, with a length of the disk 10-15 cm, are often found in the stomachs of other fish. And this despite the fact that from the very moment of hatching and for the rest of the life of the ramp, it is densely covered with small, but sharp spikes. The danger of such spikes has long been seen by people.

Polynesians from the skins of slopes made combat mittens. True, there were other species.

However, mittens made of shield -bearing slope and ramp of berg would be no worse. Nevertheless, fish, swallowing slopes, remain alive and healthy. It would be okay to cod or large bulls. A one -perimal terpug, the length of which is three times the length of the slope of the ramp, swallows them entirely. However, such cases are inappropriate and, in general, there are few enemies of the slopes.

Even the largest of the slopes in the Russian waters of the Sea of ​​Japan - thyroid - is not a massive, but to ordinary species. Nevertheless, its reserves are high enough to conduct specialized fishing. In Russia, the demand for it is low. The meat gives a little a weak ammonia smell, which, however, can easily eliminate the usual soaking in fresh water. In the fish markets of Vladivostok, the slopes are not in particular high demand.

Nevertheless, the domestic fishing of the slopes begins to develop due to high demand for this fish in the Asian countries of the Far East, especially in South Korea and China. The number of Berg is several times smaller than the shield. It is also widespread already. This is a more southern look. It is found in the Japanese Sea and the southern part of the Okhotsk, in the Pacific waters of Honshu, Hokkaido and the Southern Kuril Islands.It is believed that the spread in the depths is narrower than that of a thyroid ramp.

The capture is not awarded more. The latter may be associated with its weaker knowledge, since the distribution by depths in its general terms coincides with the thyroid ramp. As a new look, it is known relatively recently. Berg biology is similar to the biology of the thyroid ramp, and, like the thyroid, it is a promising object of fishing. In conclusion, I would like to note that the practical use of cartilage is not limited to gastronomic and pharmaceutical aspects.

Their skins are a great, very durable raw material for skin-galance products. Well, of course, exotic souvenirs are jaws, masks of monsters from slopes of slopes and other products are in great demand. Vdovin A. AMAOKA, K. NAKAYA, M. The Fishes of Northern Japan. Hokkaido Universiti. Tokai Universiti Press.