Microhabitat characteristics related to seasonal roost switching:implications from a threatened and introduced cockatoo species in an urban landscape  

作　　者：Sifeng Wang L.M.Chu 

机构地区：[1]School of Life Sciences,The Chinese University of Hong Kong,Shatin,NT,Hong Kong SAR,China

出　　处：《Avian Research》2021年第3期317-326,共10页鸟类学研究（英文版）

基　　金：supported by the Hong Kong Environment and Conservation Fund(ECF Project 02/2014);the United College Endowment Fund of The Chinese University of Hong Kong.

摘　　要：Background:Communal roosting is a common avian social behaviour,which potentially provides foraging benefits,predation avoidance or thermoregulation in birds.To identify the crucial environmental factors associated with roost site selection,most studies have focused on the comparison of physical characteristics between roosts and non-roosts.However,the differences among roosts have usually been neglected and the causes of roost switching have seldom been investigated.Methods:To explore the variations among roost sites and assess the most influential environmental factors related to seasonal roost switching,we conducted a 105-day observation on an introduced population of critically endan-gered Yellow-crested Cockatoo(Cacatua sulphurea)in an urban environment in Hong Kong from 2014 to 2016.We identified seven roost sites that were occupied in different seasons and then measured their microhabitat character-istics in terms of land use types,human disturbance and microclimate temperature.To quantify these differences,we used Pearson’s chi-squared test,partial least squares determinant analysis(PLS-DA)and one-way repeated measures ANOVA,respectively.Results:Our results distinguished roost sites occupied in three seasons,i.e.spring,summer and winter roosts,using several microhabitat characteristics.The land use types were significantly associated with roosts,where spring roosts were usually located in tree-dominated areas,which are the major feeding grounds.The discriminant analysis on human disturbance variables indicated that summer roosts were positively associated with night illumination.The microhabitat temperatures of winter roosts were significantly higher than those of most other roosts on cold nights.Conclusions:The results highlighted significant variations among roosts,and seasonal roost switching was likely driven by specific microhabitat characteristics of each roost site,such as microclimate.It also helps us understand the behavioural adaptation of birds to urban environments.

关 键 词：Communal roosting Human disturbance Land use MICROCLIMATE Seasonal variation 

分 类 号：Q958.1[生物学—动物学]