title: Analysis of whistles produced by the Tucuxi Dolphin Sotalia fluviatilis from Sepetiba Bay, Brazil.
abstract: From July 2001 to June 2002, we recorded a total of 2 h 55 min of Tucuxi Dolphin Sotalia fluviatilis vocalizations from Sepetiba Bay, Brazil (22 degrees 35'S-44 degrees 03'W). A total of 3350 whistles were analyzed quantitative and qualitatively and were divided into 124 types, by visual inspection of sonograms. The following parameters were measured: Initial Frequency, Final Frequency, Minimum Frequency, Maximum Frequency, Duration, Number of Inflections, Frequency at the Inflection Points, Frequency at 1/2, 1/4, and 3/4 of whistle duration, Presence of Frequency Modulation and Harmonics. Ascending type whistles (N = 2719) were most common, representing 82% of the total. Dolphin behavior and average group size observed during recording influenced the whistle's quantitative and qualitative parameters. The results demonstrate the great diversity of whistles emitted and indicate a functional role of these vocalizations during the observed behaviors.
authors.affiliation: Departamento de Ciências Ambientais, Instituto de Florestas, UFRRJ, Seropédica, RJ, Brasil.
authors.forename: Claudia
authors.initials: C
authors.lastname: Erber
authors.forename: Sheila M
authors.initials: SM
authors.lastname: Simão
mesh_terms: D000818:Animals; D001938:Brazil; D004289:Dolphins / Q000502:physiology*; D013018:Sound Spectrography; D014828:Vocalization, Animal / Q000145:classification*