title: Comparison of Indo-Pacific humpback dolphin (Sousa chinensis) whistles from two areas of western Peninsular Malaysia.
abstract: Differences in the acoustic variables of whistles emitted by Indo-Pacific humpback dolphins (Sousa chinensis) from two coastal locations along western Peninsular Malaysia were investigated. Duration, frequency, and frequency modulation variables were extracted from and used to characterize recordings of free-ranging humpback dolphins that were made using a broadband towed hydrophone. A total of 960 whistles from Matang Mangroves and 823 whistles from Langkawi Island were used in analyses. The whistles of Malaysian humpback dolphins covered frequencies from 1231 to 27 120 Hz with durations from 0.010-1.575 s. Significant multivariate differences were found in whistles emitted between locations. Significant differences were also found between dolphins of the two locations in their whistle duration, frequency modulation, and all frequency variables except for minimum frequency, which is likely under morphological constraints. The differences in whistles may be related to adaptations to the local acoustic habitat or unique whistles may have developed due to social interactions within each location, or broader scale differences resulting from geographic separation between the locations.
authors.affiliation: Environmental and Life Sciences, Trent University, 1600 East Bank Drive, Peterborough, Ontario K9J 7B8, Canada.
authors.forename: Jordan M
authors.initials: JM
authors.lastname: Hoffman
authors.affiliation: Institute of Ocean and Earth Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Louisa S
authors.initials: LS
authors.lastname: Ponnampalam
authors.affiliation: CetAsia Research Group, 310-7250 Thornhill, Ontario, L4J 7X1, Canada.
authors.forename: Claryana C
authors.initials: CC
authors.lastname: Araújo
authors.affiliation: CetAsia Research Group, 310-7250 Thornhill, Ontario, L4J 7X1, Canada.
authors.forename: John Y
authors.initials: JY
authors.lastname: Wang
authors.affiliation: Institute of Biological Sciences, University of Malaya, 50603 Kuala Lumpur, Malaysia.
authors.forename: Sui Hyang
authors.initials: SH
authors.lastname: Kuit
authors.affiliation: Hong Kong Cetacean Research Project, Lam Tin, Kowloon, Hong Kong.
authors.forename: Samuel K
authors.initials: SK
authors.lastname: Hung
mesh_terms: D000818:Animals; D004289:Dolphins / Q000502:physiology*; D017753:Ecosystem; D019156:Indian Ocean; D013018:Sound Spectrography; D013045:Species Specificity; D014828:Vocalization, Animal / Q000502:physiology*