New data on diversity and distribution of fish in shallow waters in western Lake Balkhash (Kazakhstan)

Abstract

Lake Balkhash is one of the largest lakes of Asia and belongs to the Republic of Kazakhstan. The lake has suffered from alien fish introduction, water pollution and overfishing during last decades. The goal of this study was to investigate contemporary fish diversity in shallow waters in western part of the Lake Balkhash. Fish samples were collected there 2018 and 2019. The data obtained showed changes in fish species diversity and significant decrease in the proportion of juvenile commercial fish in shallow sites of western part of the lake. The distribution of species seems random and needs further study to elucidate key factors. Thus, our data indicated deterioration of shallow waters in the western Balkhash as "nursery" for commercial fish species.