Study and comparison of the habitat suitability indices of Cyprinion macrostomum Heckel, 1843 from Zab River in four seasons

Knowledge of habitat requirements of aquatic animals plays an important role in fisheries and protection programs of aquatic ecosystems. Hence, this study was conducted to investigate the suitability indices of habitat use and habitat suitability index (HSI) of Cyprinion macrostomum in its distribution range, Zab River. A number of environmental variables, including pH, temperature, EC, TDS, elevation, water depth, river width, river slope, velocity, substrate type, and the relative abundance of C. macrostomum at 6 stations and three replications from the downstream to upstream were examined during from the fall of 2021 to the summer of 2022. The results showed that habitat suitability of C. macrostomum is different during four seasons and this species prefers areas with pH in the range 9-10, high temperature, low altitude, low bed slope, medium velocity, and gravel and slate beds without vegetation, and these environmental factors expressed during the four seasons of the year are almost similar. But EC, TDS, river width and water depth factors are distinct in different seasons and it prefers different ranges of these factors during the seasons. In spring and summer preferred the lower width and depth of the river, and in winter and autumn seasons preferred the width greater and depth higher of the water.