unison calling
n.— «The breeding adults are noisiest now during the mating ritual, when pairs are engaged in what is known as “unison calling.” They throw their heads back and unleash a stream of songs and rattles, turning their heads back and forth. This throws their voices into many different directions, which makes it tricky to know exactly where the sounds are coming from. Their windpipes form a loop within the breastbone, which makes their calls so resonant.» —“The return of the cranes” by Elizabeth Laden Island Park News (Idaho) Apr. 23, 2009. (source: Double-Tongued Dictionary)