7.4 Wednesday, Jan. 4 Photoperiodic and Social Regulation of Song Rate and Structure in Male Border Canaries (Serinus canaria) ALWARD, B.A.*; ROUSE, M.L.; STEVENSON, T.J.; BALL, G.F.; The Johns Hopkins Univerisity ; The Johns Hopkins Univerisity ; The Johns Hopkins Univerisity ; The Johns Hopkins Univerisity firstname.lastname@example.org
Songbird species exhibit marked variability in the types and quality of song produced across the seasons. Here, we investigated the effects of photoperiod and social milieu on variation in both song output and structure. We conducted our studies in Border canaries (Serinus canaria), a strain that is very responsive to changes in photoperiod. We housed male canaries alone on short days (SD) or alone on long days (LD) for fourteen days. Furthermore, an additional group of LD males were paired with a female for fourteen days. We analyzed: 1) number of songs, 2) number of special syllables that are attractive to females, 3) duration of song, 4) latency to sing, 5) amplitude, 6) energy (a measure of amplitude), and 7) entropy variance (an inverse measure of the uniformity of a signal). LD-Alone birds sang more songs throughout the experiment and tended to sing earlier in the day than the other groups. LD-Alone birds also exhibited increases over time in the energy of their songs. By day 7, these birds were singing with more energy than the other groups. LD-Alone birds also increased the number of special syllables sung over time in a near-linear fashion, while the other groups did not. Another feature that distinguished LD-Alone birds is that they sang with higher entropy variance than the other two groups. Therefore, photoperiod and the social environment differentially regulate song output and structure in Border canaries: LD-Alone birds sang more songs and earlier than SD and LD-Paired birds and they sang louder and with less uniformity. We hypothesize that LD-Alone birds emphasize these changes in order to broadcast a complex signal to attract a potential mate.