Contextual variations in calls of two nonoscine birds: the blue petrel Halobaena caerulea and the Antarctic prion Pachyptila desolata. (18th May 2021)

• Record Type: Journal Article
• Authors: Gémard, Charlène; Planas-Bielsa, Víctor; Bonadonna, Francesco; Aubin, Thierry
• Editors: Naguib, Marc
• Is Part Of: Behavioral ecology. Volume 32:Number 4(2021)
• Page Start: 769
• Page End: 779
• Publication Date: 2021-05-18
• Subjects: acoustic communication -- frequency shift -- motivation -- petrels -- seabirds -- vocal plasticity; Animal behavior -- Periodicals; Behavior evolution -- Periodicals; Ecology -- Periodicals; Psychology, Comparative -- Periodicals; 591.5
• DOI: 10.1093/beheco/arab020
• Languages: English
• ISSNs: 1045-2249

Abstract

Abstract: Bird vocalizations are critical cues in social interactions as they convey temporary information varying with the social context, for example, the signaler motivation when facing a rival or a potential mate. To date, literature mainly focused on learning birds. Burrowing petrels (Procellariidae) are nonlearning birds with a limited vocal repertoire. Bachelor males communicate with conspecifics with a single call emitted in three situations: in the absence of a certain auditory (spontaneous calls), toward females (female-directed calls), and toward males (male-directed calls). We first hypothesized that, although the call structure is preserved, temporal and spectral parameters vary between the three call types of bachelor males, translating different motivations (Motivation Hypothesis). To go further, we hypothesized that acoustic variations in male-directed calls indicate the signaler's aggressive motivation and, therefore, the variations are similar whether calls are produced by breeder or bachelor males (Breeding Status Hypothesis). We tested the two hypotheses performing field playback experiments on two petrel species: the blue petrel ( Halobaena caerulea ) and the Antarctic prion ( Pachyptila desolata ). Despite the obvious call stereotypy, we observed temporal variations and frequency shifts when males react to a female or a male, which may translate the sexual or aggressive motivation of the signaler. Furthermore, the similarity of variations in male-directed calls of both breeder and bachelor males suggests the aggressive motivation. So far, vocal plasticity in nonlearning birds has been greatly underestimated. Here, we highlighted the expression of different motivations through vocal variations and the ability to produce frequency variations in species with genetically coded vocalizations. Abstract : In burrow-nesting seabirds, the details in male calls make a great difference to their meaning. Using a field playback experiment, we showed that male petrels produce the same stereotyped calls toward another male or a female but with subtle variations according to the social context. They show aggressiveness to rivals and sexual arousal to potential mates solely through their calls by calling longer and higher-pitched than when calling alone.