Habitat utilization during the pairing season by the Common Hill Partridge Arborophila torqueola in Baiposhan Natural Reserve, Sichuan, China

Abstract

A goal of many resource selection studies is to identify those habitats se- lected by a species. However, favorability of a particular habitat feature is likely con- tingent on such factors as landscape composition, predation risk, and an individual's resource needs. Identifying causes of variability in habitat utilization may serve to increase our understanding of the functional aspects of a species' habitat ecology. The Common Hill Partridge Arborophila torqueola is a species that requires broadleaf forest, but whose populations have declined as a result of fragmentation of subtropi- cal forest. While habitat conditions during the pairing season (March-April) are thought to be important for the Common Hill Partridge's survival and reproduction, information on habitat utilization during this period is limited. We investigated habitat utilization by Hill Partridges within Baiposhan Natural Reserve in the mountains of southwestern China. We used pointing dogs to locate Hill Partridges during the pair- ing seasons of 2004 and 2005, and measured habitat characteristics at 60 flush sites and 60 associated random sites (within 100 m of flush sites). We recorded information on terrain, vegetation traits and defoliation leaf layer. Hill Partridges mainly utilized sites within elevations of 2,400-2,900 m and with an east-facing slope of 28.6� 2.9 degrees, close to water resources and roads. The utilized sites had greater tree cover, shrub cover and thicker defoliation layers than randomly available, whereas numbers of bamboo and bamboo cover were less at flush sites than at random sites. PCA indi- cated that concealment, food, terrain and water resources best explained the birds' habitat utilization. Forest management practices that reduce poaching, livestock and logging may benefit the Common Hill Partridge through raising habitat quality and availability. Based on habitat utilization patterns of the partridges, we discussed the difference of habitat between them and Sichuan Partridge A. rufipectus, and indicated that Common Hill Partridges in the reserve should be Common Hill Partridges rather than Sichuan Partridges.