Observation of a golden cheeked warbler (Setophaga chrysoparia), utilizing a typical B-song but an atypical A-song

Abstract

From 27 March through 2 June 2017, a golden cheeked warbler (Setophaga chrysoparia), code named “Piccolo,” claimed a territory within the Balcones Canyonland Preserve near Austin, Texas and sang a combination of atypical A-songs combined with typical B-songs. To the authors’ knowledge, this A-song variant has not been previously reported. In situ observations of Piccolo’s movements were used to determine the extent of Piccolo’s defended territory. In addition, between 14 April and 7 June, an acoustic recorder was deployed in the territory to record the variant song along with the soundscape. On April 28, a second-year competitor male entered Piccolo’s territory and intense and prolonged counter-singing was recorded through May 24. The competitor produced typical A- and B-songs while Piccolo counter-sang in the aforementioned variant A-songs and typical B-songs. During the recording period, Piccolo did not vocalize any typical A-songs. Two additional competitor males that used typical B-songs were also observed and recorded. The in situ observations and acoustic analysis of Piccolo’s atypical countersigning were compared to typical interactions between other nearby birds to ascertain whether the variant song provided an advantage or disadvantage for Piccolo. [Work supported by the City of Austin.]