Nine canaries (Serinus canaria) and 8 European starlings (Sturnus vulgaris) were tested for responsiveness to conspecific song, alien song, or no sound at all. Responsiveness was assessed by letting the birds choose among perches associated with the different auditory stimuli. The birds were tested when they were adapted to short and to long photoperiods. The results showed that both species responded to song, especially conspecific song, more in the long-day condition than in the short-day one. For canaries, but not for starlings, perch selection also varied as a function of sex. These data show that responsiveness to song in songbirds changes as a function of day length. An important implication of this result is that song perception, as well as song production, may change with the photoperiod.