Abstract: In order to investigate the diversity of birds in Yongde County, Lincang, Yunnan Province and reveal their community dynamics, the fixed line transect method was used to observe birds twice a year during the breeding season (from March to June) between 2018 and 2020. A total of 15 orders, 52 families and 197 species of birds were recorded and 6 135 individuals were observed. The local bird assembly was dominated by Passerine birds, accounting for 73.60% of the total number of species surveyed. In terms of the residence type, there were 158 species of resident birds (80.20%), 19 species of summer migratory birds (9.64%), 18 species of winter migratory birds (9.14%) and 2 species of travelling birds (1.01%). Resident and summer migratory birds added up to 177 species (89.85%), which constitute the breeding birds in Yongde County. Among breeding birds, there were 113 Oriental species, 64 widely distributed species and no Palearctic species. Among different habitats, species richness (121 species), Shannon-Wiener index (H=4.147) and evenness index (J=0.864) were the highest in broad-leaved forest, while in shrub habitat, birds species richness (64 species), Shannon-Wiener diversity index (H=3.270) and evenness index (J=0.786) were the lowest. The results of oneway ANOVA indicate significant differences in encounter rate among habitats (F=2.751, df=4, P=0.037), with the highest encounter rate discovered in both farmland and shrub habitat. The Sorensen similarity of bird communities show that the species composition was most similar between broad-leaved forest and mixed forest, while it was significantly different between broad-leaved forest and shrub habitat. The Shannon-Wiener diversity index and evenness index of bird community show little difference among the three years, and the species composition of bird community was relatively stable with limited fluctuation. This study facilitates a better understanding of the species composition, community structure and diversity status of birds in breeding season of Yongde County, providing a basis for the protection and management of local bird resources.

Key words: Yongde County, avian diversity, breeding season, annual variation