tracked gazelles, (and thus, many gazelles living on the southwestern side of the
railway) could not use better sites existing on the opposite side due to the barrier
caused by the railway.
The barrier effect of the railway became more evident as more animal tracking
data were gathered. An Asiatic wild ass tracked from July 2005 to February 2006
also moved along the southwestern side of the railway but did not cross it
(Kaczensky et al. 2006, 2011b). The railway now likely forms the eastern edge of
Fig. 14.4 Underpasses on the Ulaanbaatar–Beijing Railway
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