Ichthyofaunal diversity in snow-fed Mardi Stream of Gandaki River, Central Nepal

Abstract

Abstract. Chapagain N, Pandey N, Chitrakar P. 2021. Ichthyofaunal diversity in snow-fed Mardi Stream of Gandaki River, Central Nepal. Biodiversitas 22: 2940-2948. This study assessed site-wise and season-wise diversity and investigated the potential environmental correlates of ichthyofaunal assemblage in snow-fed Mardi Stream of central Nepal by extensive fieldworks from June 2018 to April 2019. The ichthyofaunal diversity and community structure in the hill streams of the Nepal Himalaya are understudied. A total of 1850 individual fish belonging to 3 orders, 3 families, 9 genera, and 10 species were collected. Cypriniformes emerged as the most species-rich order, accounting for 92.6% of the total species. Based on Similarity Percentage (SIMPER) analysis, the major contributing species were Schizothorax richardsonii (27.58%), Garra annandalei (26.3%), and Naziritor chelynoides (10.82%). Diversity indices were found higher in summer season and downstream areas. Results from Generalized Linear Model (GLM) and Canonical Correspondence Analysis (CCA) revealed that pH, Dissolved Oxygen (DO), water temperature and water velocity had significant relationship with fish assemblages. The fish assemblages along the gradient of the stream may be interrupted due to climate factors and anthropogenic disturbances. This study provides baseline data on hill stream fishes of Mardi Stream which might be helpful for implementation of conservation approaches.

Short Communication: Fish diversity and its relationship with environmental variables in Kamala River, Nepal

“…Species under Channidae family were recorded even from the deeper section of the Seti Gandaki River basin influenced by urbanization (Pokharel et al 2018). Likewise, species such as Channa orientalis and Naziritor chelynoides recorded in lower segment of Mardi stream, Nepal showed a positive association with water temperature and negative association with water velocity, dissolved oxygen, and pH (Chapagain et al 2021). In Lijiang River, China, fish richness and diversity showed significant relation to habitat type where most species under Cypriniformes had strong relationships with turbidity, depth, and wetted width (Huang et al 2019).…”