Annual Change of Avian Species Richness in Winter at Zixi Mountain, Yunnan

The Zixi Mountain is located in north central Yunnan and is characterized by the obvious change of rainy and dry seasons. The vegetation community is dominated by evergreen broadleaved forest, with some land patches covered by pine tree succession. The Zixishan Provincial Nature Reserve was established in 1994, but data on avian species richness are limited since then. Here, we used a combination of line transects, direct counts, observations from high vantage points, night sound recordings, and infrared camera traps, to survey avian species richness during winter in the Zixi Mountain (n = 8 years, 2010−2017). The results showed that 177 species from 14 orders and 51 families were detected, which accounted for 19% of the 945 species of birds known to occur in Yunnan Province. Nine of these species were first records of Chuxiong Prefecture. Among 177 species detected, 147 (83.05%) were residents, 29 (16.38%) were migrants and 1 was occasionally encountered, which suggested residents were the majority for avian communities in winter. From regression analysis, winter species richness was positively correlated with breeding season precipitation, from which we hypothesized that breeding season precipitation contributes to the reproduction and species diversity of birds, and influencing avian winter species richness in Zixi Mountain. We detected 22 endangered bird species, and the species richness of birds in Zixi Mountain was higher than in rural areas of Chuxiong Prefecture. This suggests that Zixi Mountain is an important area for maintaining avian biodiversity in Central Yunnan.