Bottlenose dolphin signature whistle variation : a perspective on physical characteristics, long-term stability, relatedness, and disturbance effects
Year: 2017
Type: dissertation
Abstract: Bottlenose dolphin signature whistles are individually specific, modulated tonal sounds \nthat have been the focus of interest for studying the social acoustic repertoire in this species. \nHowever, there is still limited understanding about the factors that might drive variation in these \nsignals. The dolphin community in Sarasota Bay is ideal for investigating the influence of \ninterspecific and intraspecific characteristics as well as the social structure on signature whistles as \nit has been a long-term study for over 30 years. In this thesis, I investigated whether sex, age and \nsize affected the acoustic parameters and modulation patterns of signature whistles. I also \ndetermined the variation in signature whistle acoustic characteristics over a long period of time to \ntest the stability of contour patterns. To look at the possible influence of genetic relationships on \nwhistle structure, I studied the influence of maternal kinship (including mothers, grandmothers, \nsiblings and aunts or uncles) and associations during the first year of life on signature whistle \nacoustic parameters and contour modulation patterns. Since short-term responses to \nenvironmental changes can also be encoded in whistles and can lead to changes in whistle \nparameters, I investigated the effect of carrying digital acoustic devices (D-TAGs) after brief \ncapture-release session on the acoustic properties of signature whistles and dolphin behaviour. \nThe overall results of this thesis highlighted that signature whistles are arbitrary signals that have \nlong-term stability allowing them to be reliable signature calls. Mother-calf relations and social \ninteractions during very early development were found to have the highest influence on the \ncrystallisation of a signature whistle modulation pattern. Carrying suction cup D-TAGs, on the \nother hand, had no clear effect on the dolphins’ signature whistles and surface behaviour, \nconfirming that these research methods are appropriate for studying vocal behaviour in \nbottlenose dolphins.
Author: Braulio Leon‐Lopez
Language: English
Subfield: Ecology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2967378832