Comparative analysis of the song of the Rufous-collared Sparrow Zonotrichia capensis (Emberizidae) between Campinas and Botucatu, São Paulo State, Brazil.

The regional dialects or regiolects of the Rufous-collared Sparrow Zonotrichia capensis were compared between Campinas (47 degrees 06'W-22 degrees 90'S) and Botucatu (48 degrees 44'W-22 degrees 88'S), São Paulo State, Southeastern Brazil. Songs of 88 individuals from thirteen localities were recorded. Sonograms showed that two areas presented more homogeneous songs, forming two regiolects. In 11 localities most individuals shared the same song type. At the other two localities, they sang up to 5 different song types. This occurs at the boundaries of the regiolects, and was also where individuals singing more than one song type were found. Similarities between song types were not related to geographic distance between the respective singers. A comparative analysis showed similarities in these regiolects with song of populations from Northeastern Brazil.