The song of male canaries (Serinus canaria) differs greatly from one strain to another (wild and different domesticated breeds) depending on breeders' attempt during selective breedings. Female canaries (common canary strain) previously treated with estradiol were tested for their sexual copulation solicitation display in response to heterospecific and conspecific song stimuli. Heterospecific songs, winter wren (Troglodytes troglodytes) and greenfinch (Chloris chloris), elicited significantly weak reactions from females, but most of the females did react to these heterospecific songs. Two conspecific songs, the females' own strain song and a Border song, elicited significantly strong reactions compared to Harzer roller. A wild canary song has an intermediate song potential between Border and Harzer roller. As a whole these results support the ideas that artificial selection may have relaxed the strength of reproductive isolation and sexual selection.