Saltmarsh vegetation and social environment influence flexible seasonal vigilance strategies for two sympatric migratory curlew species in adjacent coastal habitats  

作　　者：Jing Zhang Hang Zhang Yu Liu Huw Lloyd Jianqiang Li Zhengwang Zhang Donglai Li 

机构地区：[1]Provincial Key Laboratory of Animal Resource and Epidemic Disease Preven-tion,College of Life Sciences,Liaoning University,Shenyang 110036,China [2]Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering,College of Life Sciences,Beijing Normal University,Bei-jing 100875,China [3]Ecology and Environment Research Centre,Department of Natural Sciences,Manchester Metropolitan University,Chester Street,Manchester M15GD,UK [4]School of Ecology and Nature Conservation,Beijing Forestry University,Beijing 100083,China.

出　　处：《Avian Research》2021年第3期327-337,共11页鸟类学研究（英文版）

基　　金：supported by National Key Research and Develop-ment Program of China(No.2017YFC1403500 to JL);National Natural Science Foundation of China(No.31911540468 and 31672316 to DL);non-profit Foundation of Marine Environment and Ecological Conservation of CNOOC(CF-MEEC/TR/2020-20 to ZZ);Natural Science Foundation of Liaoning Province of China(2019-MS-154 to DL).

摘　　要：Background:Animals need to adjust their vigilance strategies when foraging between physically contrasting veg-etated and non-vegetated habitats.Vegetated habitats may pose a greater risk for some if vegetation characteristics function as a visual obstruction but benefit others if they serve as protective shelter.Variation in group size,presence of similar species,along with variation in environmental conditions and anthropogenic disturbance can also influence vigilance investment.Methods:In this study,we quantified the vigilance behaviour of two large-bodied,sympatric migratory curlew species-Far Eastern Curlew(Numenius madagascariensis)and Eurasian Curlew(N.arquata)-in vegetated Suaeda salsa saltmarsh and non-vegetated mudflat habitat in Liaohekou National Nature Reserve,China.We used linear mixed models to examine the effects of habitat type,season,tide time,flock size(conspecific and heterospecific),and human disturbance on curlew vigilance investment.Results:Both species spent a higher percentage of time under visual obstruction in S.salsa habitat compared to mudflat habitat but in response,only Far Eastern Curlew increased their percentage of vigilance time,indicating that visual obstruction in this habitat is only a concern for this species.There was no evidence that S.salsa vegetation served as a form of cryptic background colouration since neither species decreased their vigilance effect in S.salsa habitat in spring compared to the autumn migration season.The effect of curlew social environment(i.e.flock size)was habitat dependent since percentage of vigilance time by curlews in saltmarsh increased with both the number of individual curlews and number of other birds present,but not in mudflat habitat.Conclusions:We conclude that both migratory curlew species exhibit a flexible vigilance adjustment strategy to cope with the different environmental and social conditions of adjacent and sharply contrasting coastal habitats,and that the trade-off between the risks of foraging and the abundance of prey may be

关 键 词：Flock size Foraging behaviour Linear mixed models Numenius curlews Suaeda salsa saltmarsh VIGILANCE Yellow Sea 

分 类 号：Q958.1[生物学—动物学]