Characteristics of the Wing Sounds of Four Hummingbird Species that Breed in Canada

• Published in: The Condor (Los Angeles, Calif.) Calif.), 2005-08, Vol.107 (3), p.570-582
• Main Authors: Hunter, Todd A., Picman, Jaroslav
• Format: Article
• Language: English
• ISSN: 0010-5422; 1938-5129
• DOI: 10.1093/condor/107.3.570

In contrast to vocalizations, nonvocal avian sounds have received little attention as potential means of communication. The high wing-beat frequency of hummingbirds in concert with the modified flight feathers of some species, generate sounds with the potential to play a role in communication. Technological limitations of previous studies have compromised assessment of the acoustic characteristics and importance of these sounds. This study was designed to record and analyze the sex-specific wing sounds of four hummingbird species, in order to provide a framework for further communication studies. We collected digital recordings of hummingbirds during hover flight and analyzed these with computer-based sound software. Our results showed that (1) males of all four species had higher wing-beat frequencies than conspecific females; (2) there was greater intra- and interindividual variation in wing-beat frequency than previously documented; (3) though not specifically tested, the sexual dimorphism and interspecific differences in wing-beat frequency support previous findings that wing-beat frequency is inversely related to wing length; and (4) that digital sound analysis is a powerful new tool for detailed study of wing sounds. We provide the first description of a characteristic behavior, which we have called the ‘Cobra’, in which an individual dramatically increases its wing-beat frequency. Finally, we have significantly expanded understanding of the wing trill sound produced by the modified outer primary feathers, and have shown that female Black-chinned Hummingbirds (Archilochus alexandri) also produce wing trill components despite previous beliefs that these were unique to male hummingbirds. Características de los Sonidos de las Alas de Cuatro Especies de Picaflores que Crían en Canadá Resumen. A diferencia de las vocalizaciones, los sonidos no-vocales de las aves han recibido poca atención como medios potenciales de comunicación. Las altas frecuencias de aleteo de los picaflores, en conjunto con las plumas modificadas para el vuelo de algunas especies, generan sonidos que tienen el potencial de jugar un rol en la comunicación. Las limitaciones tecnológicas de los estudios previos han dificultado la evaluación de las características acústicas y de la importancia de estos sonidos. Este estudio fue diseñado para grabar y analizar los sonidos de las alas específicos de cada sexo en cuatro especies de picaflores con el objetivo de sentar las bases para futuros