Whistle characteristics and daytime dive behavior in pantropical spotted dolphins (Stenella attenuata) in Hawai‘i measured using digital acoustic recording tags (DTAGs)
Abstract
This study characterizes daytime acoustic and dive behavior of pantropical spotted dolphins (Stenella attenuata) in Hawai‘i using 14.58 h of data collected from five deployments of digital acoustic recording tags (DTAG3) in 2013. For each tagged animal, the number of whistles, foraging buzzes, dive profiles, and dive statistics were calculated. Start, end, minimum, and maximum frequencies, number of inflection points and duration were measured from 746 whistles. Whistles ranged in frequency from 9.7 ± 2.8 to 19.8 ± 4.2 kHz, had a mean duration of 0.7 ± 0.5 s and a mean of 1.2 ± 1.2 inflection points. Thirteen foraging buzzes were recorded across all tags. Mean dive depth and duration were 16 ± 9 m and 1.9 ± 1.0 min, respectively. Tagged animals spent the majority of time in the upper 10 m (76.9% ± 16.1%) of the water column. Both whistle frequency characteristics and dive statistics measured here were similar to previously reported values for spotted dolphins in Hawai‘i. Shallow, short dive profiles combined with few foraging buzzes provide evidence that little spotted dolphin feeding behavior occurs during daytime hours. This work represents one of the first successful DTAG3 studies of small pelagic delphinids, providing rare insights into baseline bioacoustics and dive behavior.
Citation
Silva , T L , Mooney , T A , Sayigh , L S , Tyack , P L , Baird , R W & Oswald , J N 2016 , ' Whistle characteristics and daytime dive behavior in pantropical spotted dolphins ( Stenella attenuata ) in Hawai‘i measured using digital acoustic recording tags (DTAGs) ' , Journal of the Acoustical Society of America , vol. 140 , no. 421 , pp. 421-429 . https://doi.org/10.1121/1.4955081
Publication
Journal of the Acoustical Society of America
Status
Peer reviewed
ISSN
0001-4966Type
Journal article
Description
Funding to support P.L.T. was received from the MASTS pooling initiative (The Marine Alliance for Science and Technology for Scotland) and their support is gratefully acknowledged. MASTS is funded by the Scottish Funding Council (grant reference HR09011) and contributing institutions.Collections
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.