Golden-marmot alarm calls: II. Asymmetrical production and perception of situationally specific vocalizations? [Les cris d'alarme chez la marmotte dorèe : II. Production asymètrique et perception de vocalisations spècifiques?].

Résumé

Many species produce alarm calls that vary according to situation. An implicit assumption for these species is that production and perception of situationally specific alarm calls is symmetrical: perceivers respond to variation produced by signalers. The companion paper to this one (Blumstein 1995) showed that golden marmots (Marmota caudata aurea) produce variable alarm calls that vary in proportion to the degree of risk the caller perceives. Calls produced in higher-risk situations have fewer notes than calls produced in lower-risk situations. In this study, to determine the salience of the number of notes per call in eliciting different responses in a conspecific perceivers, I played back three-note alarm calls, eight-note alarm calls, and the non-alarm vocalization of a local bird to adult golden marmots. Although marmots responded differently to birds calls and alarm calls, vigilance responses to the different alarm calls were similar. Several explanations may account for the apparent insensitivity to alarm-call variation: golden marmots may require additional contextual cues to properly interpret alarm calls, perceptual abilities do not parallel production abilities, or calls may serve a generalized alerting function.