SPECIES COMPOSITION AND ABUNDANCE OF EGG AND LARVAL FISH IN THE LOWER REACHES OF GANJIANG RIVER UNDER CASCADED DEVELOPMENT.

Egg and larval fish investigation can be deduced the distribution and reproductive characteristics of adult fish. Ganjiang River is the longest river flowing into the Poyang Lake, and one of the important tributaries of the Yangtze River. Due to the construction of cascade water conservancy projects on the mainstream of the river, the fish resources have been affected. In order to correctly design protection measures of fish resources, egg and larval fish species composition and abundance at Fengcheng section in lower reaches of the river were investigated between May and June 2019. The results indicated that: (a) of the 29 species of egg and larval fish collected, and the individuals of Hemiculter bleekeri, Rhinogobius giurinus, Parabramis pekinensis, Squalidus argentatus and Xenocypris argentea were most abundant; (b) egg abundance was higher through May while larval abundance was higher during June; (c) the egg abundance of the four carps further declined and two new spawning grounds were found. Therefore, we suggested that the ecological regulation of the Ganjiang River should be managed to create flood peaks and make the daily increment of water level greater than 0.55 m when water temperature was between 18-24 °C during May to July. [ABSTRACT FROM AUTHOR]