Abstract
Twenty-live cardinals (Richmondena cardinalis) living on the campus of the University of Western Ontario at London, Ontario, had a total repertoire of 14 types of sounds, or syllables, which they used in their songs. The birds sang the syllables in various combinations to form song types, but only 10 song types were commonly used by most birds. These 10 types each consisted of only one or two types of syllables. One bird sang its 10 types in varying amounts. The results were based on tape recordings followed by analysis on a sound spectrograph instrument, or sonagraph, and also based on periods of listening.