Spatio-temporal habitat assessment of a tropical megaherbivore, Indian gaur in Bandipur Tiger Reserve, southern India

Abstract

Habitat use of large mammals is a complex ecological phenomenon determined by intricate interplays between biotic and abiotic components at multiple spatial and temporal scales. Indian gaur (Bos gaurus) is experiencing dynamic landscape transformation threats within its habitats due to various natural and anthropogenic stresses. Identification of key limiting factors acting at different scales is important for its habitat management. We evaluated the spatio-temporal scale dependent gaur habitat suitability in Bandipur Tiger Reserve, India. We recorded direct and indirect signs of gaur alongside topo-bio-climatic and anthropogenic attributes. We used weighted random forest model to predict gaur’s occurrence using sampling grids at macro (25 km²) and micro (4 km²) scales for dry and wet seasons. We found that the distribution of gaur was highly influenced by spatio-temporal scales. Shrub coverage positively affected gaur’s habitat suitability in the dry season, while waterhole density had a positive effect on it across spatio-temporal scales. The occurrence of gaur was positively (strong) influenced by distance to nearest road in the wet season but negatively (weak) influenced by the same in the dry season. We also observed contrasting effects of ruggedness at macro scale (negative) and micro scale (positive). The identified high suitable area ranged from 11.23 % to 43.83 % across scales, with the highest suitability during wet season at macro scale. Wildlife management based on studies conducted at single spatial scale can mask critical responses of a species to certain variables. Thus, this study emphasizes the significance of incorporating spatio-temporal scales into habitat suitability models for developing more comprehensive and efficient conservation strategies for conservation of species and preservation of vulnerable habitats.