Assessing the occurrence and resource use pattern of smooth-coated otters Lutrogale Perspicillata Geoffroy (Carnivora, Mustelidae) in the Moyar River of the Western Ghats biodiversity hotspot

Understanding the factors affecting presence and habitat requirements of threatened species is fundamental to their conservation. Patterns of occurrence and resource use by the vulnerable Smooth-coated otter were examined by sampling Moyar River in the Western Ghats biodiversity hotspot of India between 2015 and 2017 for otter spraints, tracks, dens and grooming sites. An occurrence-based framework was used to determine the influence of environmental covariates on otter detectability. Information on environmental parameters was recorded every 400 meters along the riverbanks in post-monsoon, winter, and summer seasons. Smooth-coated otter occurrence was high before the summer but waned drastically after monsoon when increased water levels reduce detectability of otters by washing away signs of their presence. Otter occurrence and resource use patterns were influenced by river substrate, habitat characteristics, riverbank traits and forest types. Otters prefer wider rivers, but avoided rocky areas with shallow water. Resource use patterns were determined by habitat traits and disturbance in all three seasons. Various forms of disturbances adversely affected the otter occurrence. Restoration of degraded habitats is necessary to improve the long-term conservation prospects of otters. Regional otter conservation plans need to be species-specific to help maintain the ecological balance of Moyar River ecosystem.