Assessment of spatial and habitat use overlap between Himalayan tahr and livestock in Kedarnath Wildlife Sanctuary, India

Abstract

Livestock grazing and associated habitat degradation are considered as major reasons for declining populations of wild ungulates. In the Himalaya, livestock grazing has been practiced for centuries. We studied the spatial and habitat use overlap between the Himalayan tahr (Hemitragus jemlahicus) and domestic migratory livestock (Capra aegagrus hircus and Ovis aries) in the subalpine and alpine areas of the Kedarnath Wildlife Sanctuary, Uttarakhand, India, from April 2003 to March 2004 to investigate if there was an impact of livestock grazing on the habitat use of tahr in this area. Habitat parameters such as altitude, aspect, slope, and vegetation cover used by the tahr and livestock were quantified and compared. Minimal spatial overlap was observed. Tahr demonstrated preference for higher altitude and steeper terrain and occupied rocky terrain with comparatively less grass, shrub, and tree cover, while livestock occupied lower slope categories with low rock cover and more shrub and tree cover. Livestock used altitude, slope, and aspect categories in proportion to their availability. However, the difference in use of altitude and slope was not significant, and an increase in the population of the tahr over the years in the study area was concomitant to the decrease in the livestock use of the area, which raises doubts as to whether this minimal habitat overlap is an outcome of spatial displacement or exclusion of the tahr from certain habitats.