Sounds Emitted by the Bottlenose Dolphin

Lilly, John C.; Miller, Alice

doi:10.1126/science.133.3465.1689

Cited by 88 publications

(31 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Simultaneous emission of clicks and tonal calls has been described in bottlenose dolphins [67]; however reports of two-voice whistle production are lacking. If the sound production mechanism for whistles and clicks is similar [68], [69], and if both sets of phonic lips can produce both classes of call [70], then two-voice whistle production may be possible and could explain the structure of signature whistle type SW12.…”

Section: Discussionmentioning

confidence: 99%

Identification and Characteristics of Signature Whistles in Wild Bottlenose Dolphins (Tursiops truncatus) from Namibia

et al. 2014

View full text Add to dashboard Cite

A signature whistle type is a learned, individually distinctive whistle type in a dolphin's acoustic repertoire that broadcasts the identity of the whistle owner. The acquisition and use of signature whistles indicates complex cognitive functioning that requires wider investigation in wild dolphin populations. Here we identify signature whistle types from a population of approximately 100 wild common bottlenose dolphins (Tursiops truncatus) inhabiting Walvis Bay, and describe signature whistle occurrence, acoustic parameters and temporal production. A catalogue of 43 repeatedly emitted whistle types (REWTs) was generated by analysing 79 hrs of acoustic recordings. From this, 28 signature whistle types were identified using a method based on the temporal patterns in whistle sequences. A visual classification task conducted by 5 naïve judges showed high levels of agreement in classification of whistles (Fleiss-Kappa statistic, κ = 0.848, Z = 55.3, P<0.001) and supported our categorisation. Signature whistle structure remained stable over time and location, with most types (82%) recorded in 2 or more years, and 4 identified at Walvis Bay and a second field site approximately 450 km away. Whistle acoustic parameters were consistent with those of signature whistles documented in Sarasota Bay (Florida, USA). We provide evidence of possible two-voice signature whistle production by a common bottlenose dolphin. Although signature whistle types have potential use as a marker for studying individual habitat use, we only identified approximately 28% of those from the Walvis Bay population, despite considerable recording effort. We found that signature whistle type diversity was higher in larger dolphin groups and groups with calves present. This is the first study describing signature whistles in a wild free-ranging T. truncatus population inhabiting African waters and it provides a baseline on which more in depth behavioural studies can be based.

show abstract

Section: Discussionmentioning

confidence: 99%

Identification and Characteristics of Signature Whistles in Wild Bottlenose Dolphins (Tursiops truncatus) from Namibia

et al. 2014

View full text Add to dashboard Cite

show abstract

“…The cuts will therefore have to be sorted by hand to pick out the ones with whistles. In addition, some whistles may overlap broadband sounds, particularly since dolphins can produce whistles and broadband sounds simultaneously (Lilly & Miller 1961). Without an extremely advanced filter, this method will miss those sounds.…”

Section: Sturtivant and Datta 1995) What Makes Whistles Different Frommentioning

confidence: 99%

“…However, some whistles were so closely followed or preceded by broad-band sounds that the two sounds were not separated by the extraction program. In fact, a single dolphin can produce whistles and broadband sounds simultaneously (Lilly & Miller 1961). Therefore, whistles were often found overlapping broadband sounds.…”

Section: Automatic Sorting Of Soundsmentioning

confidence: 99%

Techniques for studying vocal learning in bottlenose dolphins, Tursiops truncatus

Fripp¹

1999

View full text Add to dashboard Cite

The objective of this thesis is to develop the methods necessary for evaluating the role of learning in the natural whistle development of bottlenose dolphins. Bottlenose dolphins provide a unique opportunity to study social influences on vocal learning in a highly social non-human mammal. V ocallearning is critical for the development of human language but plays a much smaller role in the vocal development of most non-human terrestrial mammals. Preliminary evidence has indicated that the signature whistles of dolphin calves are modeled on the whistles in the calves' early environments and that the calves' social interactions influence the choice of model. The methods currently used to study the acoustic and social behavior of dolphins are insufficient to evaluate the role of learning in whistle development and the social influences on that development. The techniques necessary to perform such a study have therefore been developed and tested in this thesis.The methods used to study vocal learning in various species were reviewed and a study of vocal learning appropriate to dolphins was designed. A strategy for sampling the dolphins' social and acoustic behavior was developed. To test the sampling strategy, and to provide data for the development of analysis techniques, a pilot study was performed on dolphin calves born in captivity. Focal samples of the social interactions of dolphin mothers and calves were taken over several months before and after the births of four calves, with simultaneous acoustic recordings during all focal sessions. A test of sampling times determined that five focal samples spaced throughout the day adequately represented the dolphins' behavior for the entire day. The interactions recorded during the focal samples were analyzed with loglinear analysis, multidimensional scaling, and hierarchical cluster analysis to determine the types of social relationships that occurred between the dolphins. For both calves and adults, three types of relationships were found. An analysis of a prolonged alloparenting incident demonstrated that the social relationship between mothers and calves was a care-giving relationship independent of their genetic relationship. Measures other than the total association were found to be necessary to the evaluation of the subtle relationships between the dolphins.Methods for the quantitative analysis of the whistles produced by the dolphins were needed. Therefore, programs were developed to automatically detect and extract the whistles from the recordings in an unbiased manner. Several methods for categorizing whistles were compared and hierarchical cluster analysis of dynamic time warping of extracted contours was shown to perform well for comparing both stereotyped and un-stereotyped whistles. These techniques were then used to compare the early acoustic environments of the calves born in the pilot study. The early environments of the four calves were found to be distinctive. In particular, the putative signature whistle of each calf s mother made up a subst...

show abstract

“…Could the timing of the VS be consistent with an emotional response following dopamine release, as suggested previously (Ridgway et al, 2014)? Lilly and Miller (1961) showed that a solitary dolphin in the laboratory could simultaneously emit pulsed sounds and whistles. Previously, no context has been provided for simultaneous whistling and clicking.…”

Section: Introductionmentioning

confidence: 99%

On doing two things at once: dolphin brain and nose coordinate sonar clicks, buzzes, and emotional squeals with social sounds during fish capture

Ridgway

Dibble

Alstyne

et al. 2015

Journal of Experimental Biology

View full text Add to dashboard Cite

Dolphins fishing alone in open waters may whistle without interrupting their sonar clicks as they find and eat or reject fish. Our study is the first to match sound and video from the dolphin with sound and video from near the fish. During search and capture of fish, free-swimming dolphins carried cameras to record video and sound. A hydrophone in the far field near the fish also recorded sound. From these two perspectives, we studied the time course of dolphin sound production during fish capture. Our observations identify the instant of fish capture. There are three consistent acoustic phases: sonar clicks locate the fish; about 0.4 s before capture, the dolphin clicks become more rapid to form a second phase, the terminal buzz; at or just before capture, the buzz turns to an emotional squeal (the victory squeal), which may last 0.2 to 20 s after capture. The squeals are pulse bursts that vary in duration, peak frequency and amplitude. The victory squeal may be a reflection of emotion triggered by brain dopamine release. It may also affect prey to ease capture and/or it may be a way to communicate the presence of food to other dolphins. Dolphins also use whistles as communication or social sounds. Whistling during sonar clicking suggests that dolphins may be adept at doing two things at once. We know that dolphin brain hemispheres may sleep independently. Our results suggest that the two dolphin brain hemispheres may also act independently in communication.

show abstract

Sounds Emitted by the Bottlenose Dolphin

Cited by 88 publications

References 6 publications

Identification and Characteristics of Signature Whistles in Wild Bottlenose Dolphins (Tursiops truncatus) from Namibia

Identification and Characteristics of Signature Whistles in Wild Bottlenose Dolphins (Tursiops truncatus) from Namibia

Techniques for studying vocal learning in bottlenose dolphins, Tursiops truncatus

On doing two things at once: dolphin brain and nose coordinate sonar clicks, buzzes, and emotional squeals with social sounds during fish capture

Contact Info

Product

Resources

About