Dawn singing of the Brownish-flanked Bush Warbler influences dawn chorusing in a bird community

Despite numerous studies on the function of the avian dawn chorus, few studies have examined whether dawn singing may influence the singing of other species. Here, we built on our previous study which found male Brownish-flanked Bush Warblers (Horornis fortipes) increase their dawn singing intensity after conspecific playback on the previous day. We reanalyzed those recordings to quantify the start of dawn singing in other nine sympatric songbird species. Ranking-scaling analyses identified a distinctive sequential pattern of dawn singing among these bird species between the first and the second dawn chorus, and meta-analysis showed a significant trend to singing earlier in the bird community accompanied by the increase in dawn singing intensity in Brownish-flanked Bush Warbler. Species with songs most similar to that of the Brownish-flanked Bush Warbler and species that were phylogenetically distantly related to the Brownish-flanked Bush Warbler showed a greater shift in the onset of dawn singing. Our study is one of the few studies showing how bird song influences heterospecific singing, and this may influence the temporal organization of song activity in the community, and result in synchronization in singing activities among different species, such as singing in dawn and dusk chorus.