(Rutilus frisii), a fish of the carp family. Body length, 75 cm; weight, 6 kg. Distributed in the basins of the Black and Azov seas, they enter the mouths of rivers and travel far upstream. They spawn in the second half of May on rocky stretches of rivers with swift, clean water and a rocky bottom. They feed mostly on bottom mollusks, whose shells they crush with powerful gullet teeth. A special subspecies, the kutum, a valuable commercial fish, lives in the basins of the Caspian Sea. Their numbers are not great and continue to grow smaller because of unfavorable conditions for reproduction.
(Cyprinus carpio), a fish of the family Cyprinidae of the order Cypriniformes. The carp reaches a length of 1 m and a weight of 12 kg. The fish inhabits Lake Issyk-Kul’ and the basins of the Mediterranean, Black, Caspian, and Aral seas. It also dwells in rivers of East Asia and of the western basin of the Pacific Ocean. Carps are raised artificially in Poland, Denmark, Sweden, and Great Britain. In the USSR the fish has been acclimatized in the Barabinskie lakes, Lake Balkhash, and Lake Alakol’. There are resident and migratory forms. The former live permanently in a single body of water, and the latter live in freshened areas of seas or lakes and migrate from spawning estuarine areas into rivers. Carps attain sexual maturity in the second to fifth year of life. They produce about 1.5 million roe. Spawning is intermittent, from April through July, occurring among soft vegetation in fresh or brackish coastal waters having a temperature of 12°–20°C. The roe are sticky. Carps feed on invertebrates and plants. They are commercially valuable. A cultivated form has been obtained by selection.
Z. V. KRASIUKOVA