A playback experiment is a well-established method for behavior research, especially in the study of the territorial responses of songbirds. Birds obtain information from multimodal signals, whereas only acoustic sign...A playback experiment is a well-established method for behavior research, especially in the study of the territorial responses of songbirds. Birds obtain information from multimodal signals, whereas only acoustic signals are provided in traditional playbacks. Many efforts have been made to combine visual signals with playback experiments, e.g., static specimens, videos, live birds and robotic models. Multimodal signal playback provides an elaborate way to study the behavior of focal birds. Although combining visual signals with playback experiments can elicit more authentic responses, empirical evidence remains scarce. In this study, a robot model mimicking a territory intruder was presented to Eurasian Nuthatch (Sitta europaea) to evaluate its effect on playback experiments. The experiments were conducted on 45 individuals during the 2021 breeding season in Baihua Mountain National Nature Reserve (39°83ʹ N, 115°58ʹ E), China. These 45 individuals were randomly divided into three equal-sized groups corresponding to the experimental treatments: playback sound only;sound with a static model;and sound with a dynamic model. Behavioral variables were recorded during each experiment to generate response intensity via principal component analysis. The results revealed that there was no significant difference in response intensity among the three different experimental treatments. Considering the dense habitat where nuthatches live, the robot model may have insufficiently increased the stimulation of sensory perception. We propose that the effect of visual signals during playback should be evaluated in more species and that behavioral studies could be conducted using multimodal signals to provide a more realistic representation of bird‒bird interactions.展开更多
Extra-pair paternity(EPP)is commonly found in socially monogamous birds,especially in small passerine birds,and there are interspecific and intraspecific variations in the extent of EPP.The Chestnut-vented Nuthatch(Si...Extra-pair paternity(EPP)is commonly found in socially monogamous birds,especially in small passerine birds,and there are interspecific and intraspecific variations in the extent of EPP.The Chestnut-vented Nuthatch(Sitta nagaensis)is a socially monogamous passerine bird,and verifying whether this species has EPP relies on parentage testing-S.nagaensis is not known to have EPP.In this study,we developed SNP markers of this species that are informative for parentage analysis from double digest restriction site-associated DNA sequencing(ddRAD-seq)data.A panel consisting of 50 SNP markers,with a mean heterozygosity of 0.343,was used to resolve 95% of nestlings to fathers.The combined exclusion probabilities for the first parent and second parent were 0.991 and 0.9999,respectively.This panel of SNP markers is a powerful tool for parentage assignments in S.nagaensis.In addition,we found that three offspring(7.9%)from three nests(23.1%)were the result of extra-pair fertilization out of 38 offspring in 13 nests.Our study provided information on parentage analysis that has not been reported before in S.nagaensis.It also supplemented the understudied EPP behavior of birds in Asia,contributing to a general understanding of the EPP behaviors of birds.展开更多
Background:For cavity-nesting birds,the nest entrance plays an important role in preventing predators from accessing nests.Several species of nuthatches use mud to narrow the entrance of cavities.In theory,the smaller...Background:For cavity-nesting birds,the nest entrance plays an important role in preventing predators from accessing nests.Several species of nuthatches use mud to narrow the entrance of cavities.In theory,the smaller the entrance hole size,the more effective it is against predators;however,few studies have tested whether narrowing the entrance hole size can affect the estimation of threat levels from nest predators in cavity-nesting birds.Methods:Using dummy experiments,we tested whether Eurasian Nuthatches(Sitta europaea,narrow the entrance hole of cavities)and Cinereous Tits(Parus cinereus,do not narrow the entrance hole,as a control)perform different nest defence behaviours against Common Chipmunks(Tamias sibiricus,small nest predator)and Red Squirrels(Sciurus vulgaris,larger nest predator).Results:Both nuthatches and tits exhibited stronger response behaviours(high dummy response scores)against chipmunks than against squirrels.Compared with tits,nuthatches exhibited more aggressive behaviours to chipmunks,but their responses to squirrels were similar.Conclusions:Nest defence behaviours of nuthatches to chipmunks differed from tits,and the results suggested that nuthatches might estimate threat levels of nest predators according to their narrowed entrance-hole size.展开更多
基金supported by the National Natural Science Foundation of China(No.32170491)the Scientific Research Team Project of the College of Life Sciences,Beijing Normal University,in 2024.
文摘A playback experiment is a well-established method for behavior research, especially in the study of the territorial responses of songbirds. Birds obtain information from multimodal signals, whereas only acoustic signals are provided in traditional playbacks. Many efforts have been made to combine visual signals with playback experiments, e.g., static specimens, videos, live birds and robotic models. Multimodal signal playback provides an elaborate way to study the behavior of focal birds. Although combining visual signals with playback experiments can elicit more authentic responses, empirical evidence remains scarce. In this study, a robot model mimicking a territory intruder was presented to Eurasian Nuthatch (Sitta europaea) to evaluate its effect on playback experiments. The experiments were conducted on 45 individuals during the 2021 breeding season in Baihua Mountain National Nature Reserve (39°83ʹ N, 115°58ʹ E), China. These 45 individuals were randomly divided into three equal-sized groups corresponding to the experimental treatments: playback sound only;sound with a static model;and sound with a dynamic model. Behavioral variables were recorded during each experiment to generate response intensity via principal component analysis. The results revealed that there was no significant difference in response intensity among the three different experimental treatments. Considering the dense habitat where nuthatches live, the robot model may have insufficiently increased the stimulation of sensory perception. We propose that the effect of visual signals during playback should be evaluated in more species and that behavioral studies could be conducted using multimodal signals to provide a more realistic representation of bird‒bird interactions.
基金supported by the Science and Technology Project of Yunnan(202101AT070040)the National Natural Science Foundation of China(U23A20162)+1 种基金the Yunnan Provincial Department of Education Fund for Scientific Research Project(2023Y0722)the First Class Forestry Academic Subject in Yunnan Province.
文摘Extra-pair paternity(EPP)is commonly found in socially monogamous birds,especially in small passerine birds,and there are interspecific and intraspecific variations in the extent of EPP.The Chestnut-vented Nuthatch(Sitta nagaensis)is a socially monogamous passerine bird,and verifying whether this species has EPP relies on parentage testing-S.nagaensis is not known to have EPP.In this study,we developed SNP markers of this species that are informative for parentage analysis from double digest restriction site-associated DNA sequencing(ddRAD-seq)data.A panel consisting of 50 SNP markers,with a mean heterozygosity of 0.343,was used to resolve 95% of nestlings to fathers.The combined exclusion probabilities for the first parent and second parent were 0.991 and 0.9999,respectively.This panel of SNP markers is a powerful tool for parentage assignments in S.nagaensis.In addition,we found that three offspring(7.9%)from three nests(23.1%)were the result of extra-pair fertilization out of 38 offspring in 13 nests.Our study provided information on parentage analysis that has not been reported before in S.nagaensis.It also supplemented the understudied EPP behavior of birds in Asia,contributing to a general understanding of the EPP behaviors of birds.
基金supported by the National Natural Science Foundation of China(No.31870368 to KZ,No.31770419 and No.31971402 to HW,No.32001094 to J.Yu)the Science and Technology Project Program of Jilin Provincial Department of Education(JJKH20190281KJ to J.Yu)。
文摘Background:For cavity-nesting birds,the nest entrance plays an important role in preventing predators from accessing nests.Several species of nuthatches use mud to narrow the entrance of cavities.In theory,the smaller the entrance hole size,the more effective it is against predators;however,few studies have tested whether narrowing the entrance hole size can affect the estimation of threat levels from nest predators in cavity-nesting birds.Methods:Using dummy experiments,we tested whether Eurasian Nuthatches(Sitta europaea,narrow the entrance hole of cavities)and Cinereous Tits(Parus cinereus,do not narrow the entrance hole,as a control)perform different nest defence behaviours against Common Chipmunks(Tamias sibiricus,small nest predator)and Red Squirrels(Sciurus vulgaris,larger nest predator).Results:Both nuthatches and tits exhibited stronger response behaviours(high dummy response scores)against chipmunks than against squirrels.Compared with tits,nuthatches exhibited more aggressive behaviours to chipmunks,but their responses to squirrels were similar.Conclusions:Nest defence behaviours of nuthatches to chipmunks differed from tits,and the results suggested that nuthatches might estimate threat levels of nest predators according to their narrowed entrance-hole size.
