Song Recognition Study Of Migratory Populations Of Marsh Grassbird

Bird song is a relatively long and complex voice produced mainly by male birds in the breeding season.Bird songs play an important role in species recognition in the context of territorial defense,mate guarding and mate attraction.Differences in environment and migratory behavior can influence the songs of birds which could lead to the formation of dialects and even isolation among different populations of the same species.The mash grassbird(Locustella pryeri sinensis)has 7 populations identified in China with different migratory strategies that 3 northern migratory populations sharing wintering areas with 4 southern sedentary populations.Differences in male songs has been found among different population which formed stable dialect.However,stimulus response and recognition ability of local and distant songs are still unclear.To analyze the differences of natural songs,response to male singing,and response intensity to local and allopatric stimuli in two migratory populations,local and distant playback had been carried out as simulation of male territorial invasion.From July 2017 to July 2019,the natural songs of 15 individuals in Zhalong Nature Reserve(Heilongjiang Province)and 17 individuals in Shuangtaihekou Nature Reserve(Liaoning province)were recorded,and the songs of local migratory population and distant sedentary population were used as playback to stimulate the male individuals.Differences had been found between two populations:The Element rate of trill(RET)of Shuangtaihekou population was significantly higher than that of Zhalong population,and the element rate of the entire song(RE)of Shuangtaihekou population was significantly higher than that of Zhalong population.There were differences in natural songs between the two populations,but there was no recognition barrier.After stimuli,all of the individuals approached quickly,and some of them showed wing-flapping or attack,indicating that both local and distant male songs were stimuli for mash grassbird in breeding season.After stimuli,changes of frequency,increasing of duration and element number were found in Zhalong population;only changes of frequency were found in Shuangtaihekou population.Most of song characteristics of the two migratory populations are species-specific when coping with territory invasion.But the responses of the two populations were different:the songs of Zhalong population had more changes in parameters,and the song rate changed greater.It is infired that response strength of Zhalong population was strgoner than that of Shuangtaihekou population.Both local and distant songs of males were stimulation signal for the mash grassbird in breeding season.There was no significant difference in behaviors and songs between the two populations.