Abstract:

Aims: Livestock grazing is one of the primary threats to wildlife, and elucidating the responses of wildlife to grazing disturbance is crucial for species conservation. Free-ranging livestock such as cattle and horses in nature reserves can degrade wildlife habitats. However, quantitative assessments of how livestock influence the spatiotemporal distribution patterns of pheasants remain scarce. 

Methods: From 2011 to 2015, we conducted this study at Wanglang National Nature Reserve in Sichuan Province, China. Camera trap surveys were implemented targeting Tragopan temminckii and livestock (cattle and horses). Multi-species occupancy models, kernel density estimation, and the avoidance-attraction ratios (AAR) were employed to investigate the effects of livestock grazing on the activity rhythm, habitat use, and occupancy of Tragopan temminckii. 

Results: The results revealed that in the temporal dimension, the activity pattern of Tragopan temminckii overlapped highly with that of livestock (coefficient of overlap ∆₄ = 0.74, 95% CI: 0.73–0.95), and the species exhibited significant behavioral avoidance of livestock (AAR = 3.17). In the spatial dimension, the marginal occupancy probability of Tragopan temminckii was positively correlated with shrub coverage (β = 0.16) and canopy density (β = 0.06), but negatively correlated with litter layer (β = –0.36), herbaceous coverage (β = –0.41), altitude (β = –0.20), and bamboo coverage (β = –0.10). For livestock, the marginal occupancy probability was positively correlated with canopy closure (β = 0.39) and negatively correlated with litter layer (β = –0.10), distance to the nearest river (β = –0.15), altitude (β = –0.33), shrub coverage (β = –0.54), and bamboo coverage (β = –0.25). The habitat use of Tragopan temminckii was jointly affected by livestock and other ecological factors. The presence of livestock altered the occupancy responses of Tragopan temminckii to bamboo coverage, altitude, and distance to the nearest river, driving the species to prefer habitats with higher bamboo coverage, lower altitude, and greater distance from river. 

Conclusion: We propose that grazing management measures should be implemented to promote the recovery of pheasant populations and their habitats in Wanglang National Nature Reserve.

Key words: grazing disturbance, habitat use, activity rhythm, Wanglang National Nature Reserve, camera trap, occupancy model