Occupancy and activity rhythms of the Siberian roe deer

The assessment of spatiotemporal behaviour patterns of wild species is pivotal both for conservation and for management, especially when involving rare or elusive species, or species living in delicate ecosystems, e.g. mountains. The Siberian roe deer Capreolus pygargus is a native Asian ungulate, whose ecology is still poorly known, especially on mountain ecosystems. In particular, information on its spatial behaviour and temporal patterns of activity is poor. We have assessed its patterns of circadian rhythms in relation to moon phases, with some conclusions on spatial behaviour in respect to potential predation and slope inclination. Data were collected between August and October 2019, with 35 camera-traps deployed over an area of mountain forests alternated to steppe, in Central Mongolia. Camera trap data were analyzed with occupancy models and kernel smoothers, providing a reliable assessment of the presence of Siberian roe deer, with only 1 % of false absence and a very high detection probability. This ungulate showed a bimodal temporal behaviour, with activity peaks at dawn and at early night, irrespective from moon phases. The detection of Siberian roe deer was negatively influenced by the presence of large carnivores and by increasing slope steepness.