Ichthyofaunal Diversity and Physicochemical Water Quality of Dahod Reservoir, Raisen, Madhya Pradesh, India

Abstract

This study assessed ichthyofaunal diversity and selected physicochemical water quality parameters of Dahod Reservoir in Raisen district, Madhya Pradesh, India. The reservoir, constructed in 1958, is used for irrigation and water supply and also supports aquatic biodiversity. Monthly sampling was conducted from December 2025 to April 2026 at four selected sites, namely Bithori, Dahod, Landing Centre and Imaliya Gondi, with the assistance of local fishermen. Fish specimens were collected using gill nets, cast nets and drag nets of different mesh sizes, and species were identified using standard taxonomic keys. Water quality was evaluated through measurements of air temperature, water temperature, transparency, pH, free carbon dioxide, dissolved oxygen, total hardness and total alkalinity. The study recorded 18 aquatic taxa distributed across 7 orders and 10 families. Cypriniformes was the dominant order, contributing 47% of the total recorded fauna, followed by Siluriformes (24%), Perciformes (8%), Cichliformes (6%), Beloniformes (5%), Osteoglossiformes (6%) and Decapoda (5%). The family Cyprinidae was represented by eight species and was the most abundant family. Shannon diversity values ranged from 1.519 to 1.890, while Shannon equitability ranged from 0.547 to 0.667, indicating moderate diversity with uneven species distribution. Physicochemical parameters remained within ranges generally favourable for freshwater fish survival, with pH from 6.9 to 8.5, dissolved oxygen from 6.0 to 9.8 mg/L, total hardness from 110 to 136 mg/L and total alkalinity from 136 to 190 mg/L. Overall, the findings indicate that Dahod Reservoir supports moderate aquatic diversity and maintains water quality conditions suitable for fish productivity, while continued monitoring is needed to address increasing anthropogenic pressures and the presence of exotic species.