How western meadowlarks classify their songs: evidence from song matching

Song matching during playback experiments was used to assess how western meadowlarks, Sturnella neglecta, classify variants of their primary song. In separate trials, subjects were played renditions of song types of strangers that they had in their own song repertoires and songs that were similar to their own, but of different types. Birds matched those song types that they had in their own repertoires, but responded to similar songs of different types with song types apparently chosen at random. When half-songs were used as playback stimuli, subjects were able to classify song types correctly using cues present only in the introductory portions of songs. These findings suggest that the song types human observers recognize as 'natural' units in the repertoire of this species are also recognized by the birds. A four-level classification of the variation in western meadowlark song is discussed.