[Long-term changes in the parasitic fauna of fishes in the Aral Sea].

In the period of 1967--1971 investigations were carried out of the fishes from the Aral Sea. 65 species of parasites have been first recorded from the above fishes, their total list includes 215 species. 23 of them were introduced during the acclimatization of fishes. Progressive salinity growth of this water body has caused the reduction of the distribution area and the decrease in the number of the Aral population of many species. Under changing conditions many species of monogenne and some members of other classes have preserved a wide distribution and in some places a high quantity. The cases of morbidity and mortality of fishes are reported. Materials on the parasite fauna of fishes enabled the author to establish their food relations which are affected by modern hydroregime of the Aral Sea as well as by the acclimatization of the Caspian gobiids.