GEOGRAPHIC VARIATION IN THE SONG OF CARDINALS

Abstract

Songs from 95 cardinals, Richmondena cardinalis, in 15 localities in Ontario were recorded on tape and analyzed by a sonagraph. These showed maxima of 9 to 13 syllables, per bird per locality, organized into 8 to 11 song types. The syllables and song types of any bird in a locality were similar to others in the locality. These, in turn, often differed from those of other localities in "pronunciation" of syllables, in the presence of more than one variant of a particular syllable type, in the presence or absence of certain syllables, and by different combinations of the syllables in song types. In spite of differences in dialect between localities, many syllables and song types were widespread throughout Ontario. Recordings from approximately 130 birds in Ohio, Florida, Texas, and Mexico showed that certain syllables occurred in more than one region, although the further from Ontario, the fewer were the syllables in common with it.It is concluded that dialects have arisen from the combined influences of fidelity to a locality by adults, learning of song by young from adults, and variation from several sources, involving learning, dispersal, and possibly innate factors. No conclusions are reached concerning similarities and differences among widely separated areas, although some influences are considered.