Argali Ovis ammon surveys in Mongolia's South Gobi

Abstract

The argali, Ovis ammon, a species of wild sheep, is threatened in Mongolia, suffering from poaching and competition with domestic livestock. The authors conducted ground and aerial surveys of argali in Dundgobi, Omnogobi and Dornogobi aimags (or provinces) of the South Gobi region of Mongolia. Ground surveys were conducted by vehicle and on foot, while aerial surveys were conducted using two Soviet AN-2 aircraft flying 40-km parallel transects. The interactive computer programme Distance was used to estimate population size and density. The authors observed a total of 423 argali in 85 groups (mean group size = 5.0 ± 0.6 SE), including 300 individuals in 61 groups on the ground survey (mean size = 4.9 ± 0.8 SE) and 123 animals in 24 groups during the aerial survey (mean size = 5.1 ± 1.2 SE). Population structure of the groups observed during the ground survey was 14.3 per cent males, 53.3 per cent females, 19.7 per cent lambs, and 12.7 per cent animals of undetermined sex (means = 0.7 ± 0.2 SE males, 2.6 ± 0.6 SE females, 1.0 ± 0.2 SE lambs, and 0.6 ± 0.4 SE undetermined). We estimated a population size of 3900 ± 1132 SE argali in the study area for a population density of 0.0187 ± 0.0054 SE animals/sq km. More rigorous and comprehensive surveys for argali, preferably for each distinct population, should be conducted for more accurate estimates. Argali require more active conservation and management, especially with respect to poaching and competition with domestic livestock. If sport hunting is to continue, a large portion of all money