Spatio-temporal dynamics of fish assemblage in the Datong and Xiaotong rivers, karst tributaries in the upper Yangtze River drainage: Implications for ecological adaptation and conservation of fish in rivers

The Datong and Xiaotong rivers are karst tributaries in the upper Yangtze River drainage represent considerable habitat diversity that contributes to high fish rich fishery resources two rivers. During few decades, have abruptly declined due overfishing, water pollution degradation. In order further strengthen conservation restoration of provide scientific support for management these rivers, temporal spatial dynamics assemblage were investigated present study. A total 45 species captured at 30 sample sites during four surveys conducted from March 2016 January 2017. Species richness both increased upstream downstream assemblages significantly differed between river reaches, while did not differ 4 months. variations abundance Rhynchocypris oxycephalus , Zacco platypus Triplophysa bleekeri Sinogastromyzon szechuanensis Platysmacheilus nudiventris Sinibrama taeniatus Saurogobio gymnocheilus Pseudorasbora parva Pseudobagrus truncates Opsariichthys bidens considered contribute most pattern assemblages. lack a might be attributed ecological habits short-distance migration diversified mesohabitats with riffles pools spawning, feeding or overwintering within very short range. Our results suggest spatio-temporal is highly adapted characteristics We recommend focused on mesohabitats, particularly many riffles.