Population status, habitat occupancy and conservation threats to Mugger crocodile (Crocodylus palustris) in Ghodaghodi lake complex, Nepal

Mugger crocodile is a keystone species of slow flowing fresh water ecosystem. Few studies regarding status and distribution of Vulnerable Mugger have been conducted in Nepal. However, studies on ecology and other aspects of the species are limited. The goal of this study was to determine the Mugger crocodile's population status, habitat occupancy, and conservation threats in the Ghodaghodi lake complex, located in the western lowlands of Nepal. A detailed survey was conducted on 18 lakes of the lake complex in February, 2021. The population status of the Mugger was surveyed by walking along the entire boundary line of each lake. For habitat survey, perimeter of all the lakes of the complex was divided into the number of stations spaced at 500 m intervals. Habitat factors associated with the presence and absence of the Mugger were analyzed using Generalized Linear Model under binary logistic regression and likelihood ratio test was performed to test predictors for statistical significance. During the survey, 26 muggers were recorded. The probability of sighting Mugger in the lake complex was significantly differ by distance to settlement, distance to river, and human disturbances, among the nine habitat variables examined. Similarly, habitat modification and illegal fishing were ranked as most severe threats to Mugger crocodile in the lake complex. The concerned authorities, responsible for managing the lake complex shall pay attention on controlling the major identified threats like habitat modification, illegal fishing, unmanaged infrastructure development, and pollution in the lake complex in order to support future conservation of Vulnerable Mugger population in the area. Furthermore, a detailed and extensive study is suggested to investigate the movement of Muggers between different lakes of the complex as well as from Ghodaghodi lake complex to the nearby rivers during breeding season in order to support effective planning and execution of habitat management activities of this Vulnerable species.