Evidence for lekking in chiru

Lek‐breeding or lekking is the clustering of small mating territories, which females visit primarily for mating. Although lekking is widespread in the animal kingdom, it is less commonly reported in ungulates. In this paper, we present data for the presence of lekking in another ungulate, the chiru or Tibetan antelope Pantholops hodgsonii . We drove 340 km of vehicle transects and observed chiru for a total of 249 scan samples and 22 h of ad libitum observations in the winters of 1998, 1999 and 2005 at the Arjin Mountain Nature Reserve in Xinjiang, China. We documented aggregations of chiru, courtship behaviour between males and females, dominance behaviours among males, time budgets for females at lekking aggregations as well as vegetational resources on and off the aggregations. Ninety‐two per cent ( n =617) of individuals in mixed‐sex groups were at aggregations, and at these aggregations, chiru males attempted to maintain harems in small closely spaced territories despite harassment by other males. Females spent a large amount of time feeding, but the vegetation analyses showed that these territories did not contain any resources to make them especially attractive to females, and the chiru mating system can justifiably be called lekking by multiple definitions. We discuss possibilities for future work to clarify the adaptive reasons for lekking in chiru.