Fish diversity of Rampur ghol, Chitwan, Nepal

Abstract

The present study was conducted to explore the diversity of Rampur Ghol, situated in Bharatpur Municipality, Chitwan. The fieldwork was carried out from August 2023 to February 2024, covering the summer, autumn, and winter seasons. Samples were collected from four sites, and physico-chemical parameters such as temperature, depth, pH, and dissolved oxygen were analysed. The cast net (mesh size 5 mm) and ghamka (mesh size 2 mm) were used to gather fish with the help of a local fisherman. A total of 25 fish species belonging to 6 Orders, 14 Families, and 17 Genera were recorded. The dominant order was Cypriniformes (40%), with 10 species, and the dominant family was Cyprinidae (32%), with 8 species. The most abundant fish species is Puntius sophore with a relative abundance of 22.44%, followed by Puntius ticto at 14.49%. Temperature had a positive correlation with fish variety, while pH, dissolved oxygen (DO), and water depth had negative correlations. The highest Shannon Weiner diversity index was recorded at site III (2.48) and in winter (2.59), whereas the lowest was recorded at site IV (1.99) and in autumn (2.36). The evenness was found to be maximum at site I (0.87) and in winter (0.93), whereas it was minimum at site IV (0.8) and in summer (0.8). Similarly, the highest species richness was obtained at site III (3.74) and during summer (3.98), while the lowest was obtained at site I (1.99) and during autumn (2.98). The Shannon Weiner diversity index, Margalef’s richness and evenness index revealed a strong relationship with overall species richness. Therefore, it can be concluded that Rampur Ghol provides a suitable habitat for a variety of fish species. Keywords: Diversity indices, Fish diversity, Physico-chemical parameters, Rampur Ghol