Species diversity and structure of the fish community in different types water bodies of the Ergaki natural park (Western Sayan)

Abstract

The Yenisei is one of the largest rivers on our planet. Flowing from south to north, it crosses all the natural zones of Siberia. The Yenisei basin covers the mountains and intermountain hollows of the Altai-Sayan mountainous country, the plateaus of Central and the lowlands of Western Siberia. The ichthyofauna of the flat part of the Yenisei basin is relatively well studied, while the data on the fish of the water bodies of the Western Sayan which are part of the Yenisei basin is limited in the available literature, and includes information only about the fish of some lakes. In this work, we studied of the ichthyofauna and the fish community of different types of water bodies in a specially protected natural area in the central part of the Western Sayan, in the Ergaki Natural Park — the Nizhnyaya Buiba and Bolshaya Oya rivers, and information about the ichthyofauna of Lake Oyskoye was clarified. In the studied water bodies, three species of fish (typical for rivers and lakes of the mountains of southern Siberia) were identified: Arctic grayling Thymallus arcticus (Pallas, 1776), Siberian loach Barbatula toni (Dybowski, 1869) and Eurasian minnow Phoxinus phoxinus (Linnaeus, 1758). Previously there was no information about the presence of Siberian loach in water bodies on the territory of the Ergaki Natural Park in the available scientific literature. The abundance and biomass of fish species varies significantly in different water bodies. Arctic grayling is common or dominant in rivers, Eurasian minnow is super dominant in the Nizhnyaya Buiba river and in the Oyskoe lake. In the Bolshaya Oya river, the superdominant species is the Siberian loach. Eurasian minnow in the Oyskoe lake is large of size.