Screaming Piha is famous for its characteristic qui, qui, yo call, which is audible through up to 400 m of rainforest (Snow 1961). This call is preceded by 2-3 preparatory groo notes which are made during inhalation, and less audible. Variously described as cri-cri-o, pi-pi-yo, or qui-qui-yo, the vocalizations of the Screaming Piha are well-studied in comparison to its other characteristics.
For a representative audio recording with sonogram, see audio
The sound pressure level of the song of Screaming Piha, at a distance of 1 m, is 111.5 dB ± 1.3 (n = 29); "translated for human ears, this between 120-140 phons, a value of loudness between 'discomfort' and 'pain' " (Nemeth 2004).
The song of the Screaming Piha is believed to be innate rather than learned (Oliviera 2007), although individual variation exists within leks. Fitzsimmons et. al. (2008) reported that individual songs bear lek signatures, but Kroodsma (2011) disputed their methods.
B.K. Snow (1961) observed a repeated wee-oo call made during the morning and evening. She observed no corresponding body movement like that of the main song, but the call was equally as loud. Other vocalizations are described as "loud mewing TOWW notes, often in a series, and various random piercing squeaks, whistles, and moans" (Lane, in Schulenberg et al. 2010).
Screaming Pihas sing throughout the year (Snow 1982).
During B.K. Snow’s (1961) observations of Screaming Piha, a male was found to spend 77% of his time calling from 06:45 through 17:15. Before and after this calling period, wee-oo calls were exchanged, which Snow (1961) inferred was to establish contact between individuals that had been separated by silence. Occasional silent periods, which typically last from 5-10 min, were observed throughout the day. Snow assumed that the bird was foraging during this time, as the individual disappeared from view into the canopy.
Places of vocalizing
Screaming Piha typically vocalizes in the understory and midstory, from perches that are 6-16 meters above the ground. Between calls the piha moves between many different branches within its territory, with no particular preference for any branch (Snow 1961). Similar to bellbirds (Procnias), Snow (1961) observed male pihas moving to lower branches when excited; presumably a female was in view of the male but not the researchers.
Repertoire and delivery of songs
An abrupt change in posture accompanies this vocal display. During the groo tones, the male leans forward, and then violently tips backwards during each qui syllable of the much louder qui, qui, y-o portion of the song. While calling, a small crest is raised (Snow 1982).
Individual males coordinate their songs with their immediate neighbors, alternating such that their songs do not overlap. Snow (1961) noted that this took significant coordination, as the “preparation” time for each song is approximately as long as the song itself. When excited, songs could be heard at a rate of 12 per minute, but 2-3 per minute was much more common.
Social context and presumed function
The male’s song serves to define territorial boundaries and also functions as the Screaming Piha’s lekking display (Snow 1982).