人工巢箱条件下两种山雀鸟类的同域共存机制

Abstract

Birds adjust their survival strategies in the face of interspecific competition.Integrative analysis is important for understanding the main factors accounting for coexistence mechanism of different species.Parus major and Parus varius are long-term coexistence avian species in eastern mountainous area of Liaoning province.However,we still know little about the mechanism accounting for their coexistence.During March to July in each year from 2009 to 2011,we attracted both species with artificial nest boxes.With the aim to reveal the mechanism of their coexistence,we analyze the breeding habitat selection and reproduction strategy for both species. The results showed that niche separation was the underlying mechanism for the long-term coexistence.Both of those two species immediately started to breed when breeding season arrival.Both of them showed two breeding peaks in each year.When environmental quality was poor,they chose brood reduction strategy in order to improve reproductive success.The breeding strategies for those two species belonged to k-choice,with that of Parus major was slightly close to r.Parus major had high egg number but low reproductive success,whereas Parus varius had low nest egg number and high reproductive success. Based on step discriminant analysis,we found that the average height of trees,nest height from ground,and tree abundance were important factors accounting for nest site selection of Parus major.For Parus varius,the average height of trees,vegetation types,and the average height of shrubs were important factors.Comparing the nest site selection activities of those two species,they both like their nest boxes in old forest and have some angle and vegetation around growth lush.Parus major often paid more attention to the safety performance of their nest sites as indicated by the fact that their nest sites were usually apart from the ground.In contrast,Parus varius usually located their nest sites in mixed wood,which may be closely related to its food structure.