Diet characteristics of wild sheep (Ovis ammon darwini) in the Mengluoke Mountains, Xinjiang, China

Abstract

In most arid and semi-arid regions of the world, domestic livestock and native wildlife share pastures, and their competition for forage and habitat is thought to be a serious conservation issue. Moreover, unmanaged grazing by livestock can cause the population decline in wild ungulates. The diet of an animal species is a determining aspect of its ecological niche, and investigating its diet has been one of the initial steps in basic ecology study of a new species. To get an approximate understanding of the interspecific food relationships of argali (Ovis ammon darwini) between sexes, and sympatric domestic sheep and goats, we compared the diet compositions and diet-overlaps among these herbivores, i.e., male argali, female argali, domestic sheep, and domestic goats in the Mengluoke Mountains of Xinjiang, China by using micro-histological fecal analysis. Female argali, male argali, domestic sheep and domestic goat primarily consumed forbs (43.31%±4.86%), grass (36.02%±9.32%), forbs (41.01%±9.18%), and forbs (36.22%±10.61%), respectively in warm season. All these animals consumed mostly shrubs (female argali: 36.47%±7.56%; male argali: 47.28%±10.75%; domestic sheep: 40.46%±9.56%; and domestic goats: 42.88%±9.34%, respectively) in cold season. The diet-overlaps were relatively high among all species in cold season with values ranging from 0.88 to 0.94. Furthermore, Schoener's index measured between each possible pair of 4 herbivores increased from the warm season to the cold season. The results illustrate that the high degree of diet-overlap of argali and domestic livestock (sheep and goat) may pose a threat to the survival of the argali in cold season. From the viewpoint of rangeland management and conservation of the endangered argali, the numbers of domestic sheep and goats should be limited in cold season to reduce food competition.

A Case Study on the Convection Initiation Mechanisms of an Extreme Rainstorm over the Northern Slope of Kunlun Mountains, Xinjiang, Northwest China

“…Figure 2 shows that the maximum accumulated precipitation during the heavy precipitation event is mainly concentrated in the vicinity of the northern slope of the KLM. Cumulative precipitation for the process exceeded 80 mm at 13 automatic weather stations (AWSs), which suggests that this rainstorm, like previous rainstorms in this region [59][60][61][62][63], is closely related to the topography of the north slope of the KLM. It was found from the observations at nine stations (Figure 2b) that the accumulated precipitation during the heavy precipitation event significantly exceeded the over 50 years (1966-2018) of climatologically averaged accumulated precipitation intensity in June at all 9 stations.…”