Supplemental Feeding and Dawn Singing in Black-Capped Chickadees

Abstract

Abstract. The dawn chorus is a collective behavior involving a network of birds signaling at the same time. Two hypotheses can explain the mechanisms of dawn singing. The “condition-dependent hypothesis” states that the dawn chorus consists of a “broadcast network” in which the signal is given in all directions but is not dependent on the singer's neighbors' chorus. The song output is condition dependent and can thus be limited by the amount of food to which a signaler has access to in its territory. On the other hand, the “social-dynamic hypothesis” states that during the chorus the birds are constantly interacting with their neighbors. Under this scenario, the dawn chorus consists of an “interactive network” and the song output is not dependent on the condition of the signaler but on the interaction with the neighbors. To determine which scenario best explains the mechanisms of the dawn chorus in the Black-capped Chickadee (Poecile atricapillus), we set up a supplemental-feeding experiment in a dyadic f...