title: Dolphins adjust species-specific frequency parameters to compensate for increasing background noise.
abstract: An increase in ocean noise levels could interfere with acoustic communication of marine mammals. In this study we explored the effects of anthropogenic and natural noise on the acoustic properties of a dolphin communication signal, the whistle. A towed array with four elements was used to record environmental background noise and whistles of short-beaked common-, Atlantic spotted- and striped-dolphins in the Canaries archipelago. Four frequency parameters were measured from each whistle, while Sound Pressure Levels (SPL) of the background noise were measured at the central frequencies of seven one-third octave bands, from 5 to 20 kHz. Results show that dolphins increase the whistles' frequency parameters with lower variability in the presence of anthropogenic noise, and increase the end frequency of their whistles when confronted with increasing natural noise. This study provides the first evidence that the synergy among SPLs has a role in shaping the whistles' structure of these three species, with respect to both natural and anthropogenic noise.
authors: University of Torino, Life Sciences and Systems Biology Department, Torino, Italy.
authors: Elena
authors: E
authors: Papale
authors: University of Torino, Life Sciences and Systems Biology Department, Torino, Italy.
authors: Marco
authors: M
authors: Gamba
authors: Society for the Study of Cetaceans in the Canary Archipelago (SECAC), Lanzarote, Spain.
authors: Monica
authors: M
authors: Perez-Gil
authors: Society for the Study of Cetaceans in the Canary Archipelago (SECAC), Lanzarote, Spain.
authors: Vidal Martel
authors: VM
authors: Martin
authors: University of Torino, Life Sciences and Systems Biology Department, Torino, Italy.
authors: Cristina
authors: C
authors: Giacoma
mesh_terms: D000818:Animals; D004289:Dolphins / Q000502:physiology*; D009622:Noise; D013018:Sound Spectrography; D013045:Species Specificity; D014828:Vocalization, Animal