Niche and Interspecific Relationship of Breeding Birds in Urban Parks
Understanding niche and interspecific relationship of bird species in cities is conducive to identifying their coexistence mechanism.From April to August 2021,using the line-transect method,we conducted bird surveys at 12 urban parks in Liuzhou,Guangxi.In this study,we use Levins niche breadth index,Pianka niche overlap index and Spearman rank correlation coefficient to measure niche characteristics and interspecific relationships of 14 breeding bird species.Our study shows that the Levins niche breadth of Zosterops japonicus is the highest,while the niche overlap of Pycnonotus sinensis and Copsychus saularis is the highest.There is a significant linear correlation between the niche breadth of birds and the number of parks with the birds,while bird communities show significant positive associations and the rates of positively associated species pairs in bird communities are much higher than the rates of negatively associated species pairs at that.This supports the conclusion of overall positive community associations.The niche overlap of bird species is affected by the functional distance of species.The closer the functional distance,the greater the niche overlap and the higher the probability of co-occurrence.This study provides the empirical data and new insights over the coexistence of bird species in cities.We suggest that priority should be given to conserving the habitat of specialized species in urban habitat environments.Additionally,increasing the habitat complexity of urban parks to meet the ecological needs of different bird species could promote the coexistence of urban bird species and enhance ecosystem services and functions.