Habitat selection of smooth-coated otters (Lutrogale perspicillata) in the peri-coastal, urbanised landscape of Goa, India

Abstract

Human development can have detrimental impacts on the environment and its contained ecosystems. However, several species have adapted to thrive in human-modified landscapes. This study was aimed to assess habitat selection of threatened smooth-coated otters (Lutrogale perspicillata) in the peri-coastal landscape of Goa, India. In the Indian context, there are significant gaps in knowledge pertaining to factors that influence otter occurrence in such environments. Otter presence/absence in 78 1 km2 plots across two river catchments was modelled against several habitat variables including measures of agricultural pollution, salinity, mangrove cover, and fishing presence. The effect size and direction of relationships between the probability of otter occurrence and the habitat variables were analysed by building a set of candidate generalised linear models. The models were subsequently ranked using small-sample Akaike’s information criterion (AICc). Analysis indicated that water salinity, mangrove cover, and fishing presence had a significant positive influence on otter occurrence. However, the concentrations of agricultural pollutants (nitrates, phosphates, and sulphates) were not contributing factors in influencing otter occurrence in the surveyed landscape. The metrics used in this study can be applied for preliminary assessments of presence and occupancy of otters in other coastal landscapes of India, and aid in the conservation of the species.