Hearing and vocalizations in hybrid Waterslager-Roller canaries (Serinus canarius).

A male canary from the Belgian Waterslager strain, which is known for its elevated high-frequency thresholds and a female of German Roller canary with normal high-frequency thresholds were bred. Operant techniques and a psychophysical tracking procedure were used to measure auditory sensitivity of six F1 hybrid canaries from this cross. Three patterns of auditory sensitivity were observed in the six hybrid birds. Four birds showed elevated high-frequency hearing characteristic of the Belgian Waterslager strain; one bird showed normal hearing, and one bird showed an intermediate pattern of auditory sensitivity. A spectral analysis of contact calls recorded from these F1 hybrid canaries showed a spectral distribution of energy which was intermediate between that of Belgian Waterslager strain and the German Roller strain. These results suggest there may be a relation between hearing sensitivity and the spectral distribution of energy in the calls of domestic canaries. Such hybrids may prove useful for examining the genetic basis of more complex behaviors such as vocal learning.