Composition Of Common Woody Plant Species And Their Influence On Bird Communities In Urban Green Areas

Abstract:Urban green areas have already been confirmed as important habitat of birds in fast urbanized areas. Woody plants composition has significant influence to the structure of bird communities in urban green areas. Therefore, to enhance the function of public green areas as wild bird habitats, we studied how woody plants would influence the composition of bird community in Binjiang Forest Park, a typical urban green area in Shanghai city. A total of5,368bird individuals were recorded during a bird surveys carried out between2009and2010, which comprised64species, from25families,10orders. Bird abundance showed significant differences in different months with the two highest abundance recorded in April and November. Data of bird species richness showed a two-peak curve with the highest abundance recorded in April and December. Meanwhile, Simpson index revealed a significant difference of bird diversity during the entire year, with the highest value recorded in October and the lowest in August. A total of77woody plant species were identified in the park by a square plot (400m2per each square) sampling analysis. Only15of them were common species (nine arbors, and six shrubs, i.e., woody species recorded in no less than five square plot), among which, fruiting seasons of12species were periods during September to the next February (autumn and winter), while the main seasons of forestry insects outbreaks on these plant species occurred from May to November (summer and autumn). Using a principal component analysis, all birds observed on the15woody plant species were grouped into eight guilds according to their diets, foraging behaviors, and distributions in various vegetation layers. The Spearman’s correlation analysis indicated that the autumn-winter fruiting season significantly positively correlated with five bird guilds including vegetarians, omnivores, raptors, and insectivores. The abundant food supply coincided with the highest bird abundance and richness in autum and winter. In addition, the importance of each common woody plant species on bird community was also evaluated based on the comprehensive evaluation of the relative richness, the relative abundance and the relative number of guilds of birds. Studies show that the fall and winter fruiting plants provide a rich food resources for terrestrial migratory bird; Poplar, maple, camphor are the highest value angiosperms in tree layer, and followed with gymnosperms. The shrub layer is low on birds reflect the importance of the park shrub layer functions need to be strengthened. Comments and recommendations were then provided based on the research results for the purpose to improve the function of urban green areas as wild bird habitats.