Nighttime and daytime habitat use
Based on the GLMM model results, we revealed that leopard nocturnal and diurnal activity during the four moon phases changed in response to habitat variables. Specifically, during the daytime, leopards preferred to be closer to deciduous forest and secondary roads, and to use areas of higher elevation (and vice versa for nighttime). We assume that these significant variables are associated with movement and hunting grounds for leopards at both day and night on a daily basis, offering higher concealment in deciduous forest while undistributed roads provide substrate for territory marking (Macdonald et al., 2010) and also facilitate leopard travel (Carroll and Miquelle, 2006). Finally, in cat species, prey movement is the primary factor influencing habitat selection (Hayward et al., 2007). While we expect that leopards move throughout the fragmented landscape by using high elevation corridors, these highest areas also may provide suitable habitat and maximum hunting opportunity for ungulates or medium sized prey (PU et al., 2019); the relationships with elevation were consistent across leopards and two of three prey species studied, while the leopards and roe deer had similar use of areas near to secondary roads during the daytime.
In addition to the results here derived from camera trap data, field observations (unpublished data) and literature sources validate some of our conclusions concerning prey activity. For example, we encountered a great number of footprints of roe deer on (snow-covered) secondary roads during winter field trips, as well as fecal pellets, footprints, and bedding sites of wild boar in mixed forest habitat. In the case of roe deer and secondary roads, we also observed that dogs used these roads and found that they may attack ungulates at nighttime, forcing these prey animals to temporally shift their use of the landscape to minimize risk (Young et al., 2018). With regards to mixed forests, (Acevedo et al., 2006) concluded that wild boar select broad-leaved mixed forest as habitat, as these environments, dominated by Chinese red pine (Pinus tabuliformis ) and Liaotung oak (Quercus liaotungensis) trees, provide foraging opportunities. While boar have been found to avoid high elevations during nights (Roberts and Bernhard, 1977) and we may have suspected that this may be to avoid the predator vantage points at high elevation, leopard and boar showed similar trends in daytime/nighttime use, though we here offer a new insight into how elevation use may vary within a daily 24-hour cycle. Finally, Tolai hare showed a preference to be near open grassland and far from human settlement during the daytime and similar results have also been found for other lagomorph species in the Karakorum range, Pakistan (Zaman et al., 2020a).