April 23, 2014
Post by guest student blogger Nathaniel Young – thanks for teaching us a little bit about Chickadee-speak, Nathaniel!
As winter begins to fade across the North, one of the first sounds of spring to meet your ears is likely to be the sweetly whistled “fee-bee” song of the Black-capped Chickadee. Perhaps you have often noticed multiple males singing at once. Indeed, behaviorists have understood for a while now that chickadees, like many other songbirds, use song to establish territories, signal aggression, and maintain social hierarchies. However, new research indicates that chickadees use information conveyed through song in ways more complex than we may have previously thought.
A recent article in the journal Behavioral Ecology reports on findings from Queen’s University Biological Station in Ontario. Researchers Cory Toth, Daniel Menill, and Laurene Ratcliffe placed color bands on the legs of a small population of Black-capped Chickadees so that they could easily tell apart individuals, and with the coming of spring, mapped out the territories of singing males.
They then conducted an experiment using three speakers (labelled A, B, and C) forming a triangle pointing inward toward the center in order to simulate the effects of intruding males. We understand from previous studies that males advertise their dominance over other males by singing at the same time as other males. Using this knowledge, the researchers played a series of song contests between the speakers, telling the chickadee that “male” A was dominant to B and that B was dominant to C, but giving no direct information about dominance in the interaction between A and C.
As it turns out, during the playback between speakers A and C, the great majority of chickadees approached and signaled aggression toward A, suggesting that they were able to figure out from listening to the other simulated contests that since A was dominant to B and B was dominant to C, A must be dominant to C. Such an ability to eavesdrop on songs of multiple other males and integrate all the information on dominance may be quite useful in maintaining hierarchies in groups of chickadees and in helping new males figure out who’s who in the neighborhood.
Toth, Cory; Daniel Menill, and Laurene Ratcliffe. “Evidence for multicontest eavesdropping in chickadees.” Behavioral Ecology 23.4 (2012) : 836-842.