Ordinary Marinka - Schizothorax intermedia
This representative of the unique mountain-Asian fauna inhabits both rivers and standing water bodies—lakes and reservoirs. Marinkas, being typical inhabitants of turbulent mountain streams, have an elongated torpedo-shaped body, which allows them to easily overcome strong currents and waterfalls when they ascend rivers in search of spawning grounds. Their bodies are covered with small but dense scales and slime, which ensures easy gliding in the water. However, the role of the slime covering the fish's body is not only this—it also serves a protective function and acts as thermal insulation. It has been observed that in winter, when fish lie in deep holes in hibernation, their bodies are covered with a thicker layer of slime than usual, which protects them from hypothermia.
All marinkas (as well as osmans) have their anal opening and anal fin bordered by larger scales than those on their bodies. This is the so-called "cleft," from which the name of the subfamily "cleft-bellied" comes, uniting marinkas and osmans. There are two pairs of whiskers on the head.
The coloration of the body changes depending on the transparency of the water in the marinka's habitat. In clear water, the back is dark brown, the head is olive green, the sides are orange, and the belly is white or light yellow. In murky water, it acquires a silvery-white color on the sides and a light gray coloration on the back. It reaches a length of 70 cm and a weight of 3 kg or more.
The ordinary marinka is widespread across a vast territory of Central and Middle Asia. It inhabits the upper and foothill sections of the Indus, Hilmend, Tarim, and Amu Darya rivers. In Kyrgyzstan, the ordinary marinka is found in the basin of the Naryn River with all its tributaries, the Chatkal River, Lake Sary-Chelek, and the Sary-Jaz River with its tributaries (Tarim basin). In Lake Issyk-Kul and the basins of the Chu and Talas rivers, it is replaced by subspecies of the Ili small-scaled marinka.
The ordinary marinka demonstrates an astonishing adaptability to life in different conditions, which has allowed it to inhabit water bodies across a vast territory with various natural-climatic and hydro-ecological conditions.
The marinka reaches sexual maturity at 3 to 5 years of age, with males usually maturing a year earlier than females.
Due to the fact that the ordinary marinka, like other species of marinkas, spawns in portions, that is, in several batches, its spawning period is significantly stretched from April to September, which in the conditions of low-food mountain rivers ensures better survival of the young. Spawning usually occurs at night. The female, accompanied by several males, chooses small streams or river backwaters with calm water flow and sandy-stony bottom for spawning. Marinkas living in lakes or reservoirs migrate to rivers or shallow areas where groundwater emerges and suitable solid substrates (gravel, pebbles with sand) free from aquatic and submerged vegetation. The numerical predominance of males over females ensures better fertilization and fertilization of the eggs in the water flow conditions.
The eggs of the marinka are large (up to 3 mm in diameter when swollen), sticky. It should be noted that the eggs of this fish, like those of the osman, are toxic, but their toxic properties are dangerous only for humans and warm-blooded animals. Individual fecundity is relatively low. In five female marinkas caught in July 1965 in Susamyr, measuring 15 to 34 cm, the number of eggs ranged from 1500 to 11810. In the Toktogul Reservoir, females measuring 30 to 46 cm had a fecundity ranging from 8.4 to 20.9 thousand eggs.
The marinka is an omnivorous fish. Its diet includes aquatic invertebrates (larvae of caddisflies, mayflies, chironomids, beetles, roundworms), aerial insects, and small fish species (bullheads, sand gobies). A significant part of its diet consists of vegetation (filamentous algae) and detritus flakes. The growth rate of the ordinary marinka, like that of all mountain-Asian fish species, is slow. At one year of age, it has a body length of 5 to 6 cm, while five-year-old fish measure 22 to 25 cm in length and weigh 200 to 300 g.
In Kyrgyzstan, the ordinary marinka has commercial significance only in the Toktogul Reservoir, where its stocks began to be exploited in 1978. The industrial nets used for catching marinkas with a mesh size of 38 mm catch 31.6% of immature females and 42.1% of first-time spawners, which causes significant harm to the reproduction of this valuable species in the Toktogul Reservoir.
Moreover, poaching thrives in this water body, which requires urgent regulation of fishing and protection of fish stocks in the artificial reservoir. In other water bodies of Kyrgyzstan (Naryn with its tributaries, Lake Sary-Chelek, etc.), the marinka is an object of recreational fishing.
Fish