Vigilance behaviour during the calving season in female Tibetan antelopes (Pantholops hodgsonii)

Tibetan antelopes (Pantholops hodgsonii) migrate great distances to specific delivery and calving areas. In the current study, we investigated calving site selection and vigilance behaviour during delivery and nursing in migratory female Tibetan antelopes at Zonag Lake. According to observations and analysis, the females were distributed south of Zonag Lake, where vegetation was abundant. We determined their dates of migration (crossing the Qinghai-Tibet Highway observation site), showing a shift of one month during the period from June in 2008 to May 2021. Results also showed that 81.4% of females expressed high vigilance behaviour during calving and nursing compared to those without calves (7.1%). From delivery until calf standing, females were highly vigilant and spent considerable time scanning, with 96% of females showing vigilance behaviour. Females with calves (average 9.94 & PLUSMN; 0.62 s) spent more time on vigilance behaviour than females without calves (average 6.25 & PLUSMN; 1.38 s). Females with newborns spent the greatest amount of time being vigilant (average 51.63 & PLUSMN; 4.24 s). These results not only identify basic Tibetan antelope calving behaviour, but also provide scientific analysis and evidence for further ethological research on female Tibetan antelopes.