Interactions Between Livestock and Ladakh Urial (Ovis vignei vigei)

Abstract

The Ladakh urial is a highly endangered and endemic subspecies of wild sheep. Past hunting pressures had decimated the population to extremely low levels. Recent estimates (1,000-1,500 individuals) suggest a marginal increase in numbers. The Ladakh urial occupies plateaus and gentle slopes along the lowermost elevations in the Indus and Shyok Valleys, areas that are easily accessible and heavily used by humans. This is also the most heavily populated area and due to geopolitical reasons, receives the highest developmental benefits. Due to such changes the Ladakh urial may be highly vulnerable to population decimation. Pastoralism is a way of life in bulk of the Ladakh Trans-Himalaya; a region Where wildlife including endangered species such as the urial and snow leopard are not restricted inside wildlife Protected Areas alone. Such species thus share their habitat with the over 3,00,000 livestock that occurs in the region. Recent studies from the Trans Himalaya have indicated competition with livestock as an important reason for the decimation of wild herbivore populations. This study thus aimed to investigate the interactions between the endangered Ladakh urial and livestock during the winter of 2002-03, a season of resource scarcity. We investigated the habitat selection of the Ladakh urial and its separation with livestock at the level of space, habitat variables and diet, to gather evidence for competition. Four trails were walked 10 times each to obtain information on the habitat usage by the urial and livestock. Further information on livestock use was gathered from the herders using semi-structured interviews and resource maps. Diet of both urial and livestock was investigated by examining recently foraged sites using 10, 1 mX1 m quadrats at each such site. All sightings from the trails were plotted on a 1 :50,000 501 Toposheet. A 500mX500m grid was overlaid on these locations to obtain the grids used exclusively by the urial and livestock and by both together to calculate spatial separation. Both, Ladakh urial and livestock primarily used the mid elevation zones (4,121- 4,400m) with gentle to moderate inclination (<30°). However, along the elevation gradient there was some separation in that the urial used the uppermost elevations to a substantial degree (44%) even during the cold winter season, which livestock avoided.The findings of this study thus show that the habitat and diet requirements of Ladakh urial and livestock sharing the range were similar during the winter season. The relatively high use of the sparsely vegetated uppermost elevations of the range by urial, where the cost of foraging is likely to be higher than the mid-elevations suggests that the urial were excluded from these areas by the livestock. We also reason that the relatively poor young:100 adult female ratio (31:100) may be a manifestation of the stress provided by such competition with livestock and survival in sub-optimal habitats.