Listen for the bellowing wail of a mating call. During the breeding period in mid-September, male unicorns "begin to seek out mature females by periodic calling. The calls are heard during early morning and late evening hours. The voice of the male unicorn has usually been described as a loud wail. Other than during breeding season, unicorns are surprisingly silent and as a result are extremely hard to find" (Paul A. Johnshard, Dragons and Unicorns: A Natural History, 1992). The waveform of a unicorn's mating bellow.