ABSTRACT
Two dolphins carrying cameras swam in the ocean as they searched for and marked mine simulators – buried, proud or moored. As the animals swam ahead of a boat they searched the ocean. Cameras on their harness recorded continuous sound and video. Once a target was detected, the dolphins received a marker to take to the simulator's location. During search and detection, dolphins made almost continuous trains of varying interval clicks. During the marking phase, shorter click trains were interrupted by periods of silence. As the dolphins marked simulators, they often produced victory squeals – pulse bursts that vary in duration, peak frequency and amplitude. Victory squeals were produced on 72% of marks. Sometimes after marking, or at other times during their long swims, the dolphins produced click packets. Packets typically consisted of two to 10 clicks with inter-click intervals of 7-117 ms followed by a silence of 223-983 ms. Click packets appeared unrelated with searching or marking. We suggest that the packets were used to improve signal to noise ratios for locating a boat or other distant object. Victory squeals produced when marking the targets suggest to us that the dolphins know when they have succeeded in this multipart task.
Footnotes
Competing interests
The authors declare no competing or financial interests.
Author contributions
Conceptualization: S.H.R.; Methodology: S.H.R., J.A.K.; Formal analysis: S.H.R., D.S.D.; Investigation: S.H.R., D.S.D.; Resources: S.H.R.; Data curation: S.H.R.; Writing - original draft: S.H.R., D.S.D.; Writing - review & editing: S.H.R., D.S.D.; Visualization: S.H.R.; Supervision: S.H.R., J.A.K.; Project administration: S.H.R.
Funding
Funding and all animal support was provided by the U.S. Navy Marine Mammal Program.
Supplementary information
Supplementary information available online at http://bio.biologists.org/lookup/doi/10.1242/bio.031625.supplemental
- Received November 28, 2017.
- Accepted January 17, 2018.
- © 2018. Published by The Company of Biologists Ltd
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
Article Navigation
Related articles
Cited by...
More in this TOC section
Similar articles
Other journals from The Company of Biologists
Biology Open and COVID-19
We are aware that the COVID-19 pandemic is having an unprecedented impact on researchers worldwide. The Editors of all The Company of Biologists’ journals have been considering ways in which we can alleviate concerns that members of our community may have around publishing activities during this time. Read about the actions we are taking at this time.
Please don’t hesitate to contact the Editorial Office if you have any questions or concerns.
New funding scheme supports sustainable events
As part of our Sustainable Conferencing Initiative, we are pleased to announce funding for organisers that seek to reduce the environmental footprint of their event. The next deadline to apply for a Scientific Meeting grant is 26 March 2021.
Future Leader Review – early neurodegeneration of Alzheimer’s disease
A new Future Leader Review from Olayemi Olajide, Marcus Suvanto and Clifton Andrew Chapman evaluates the molecular mechanisms that may explain the vulnerability and susceptibility of the entorhinal cortex to early neurodegeneration during the pathogenesis of Alzheimer's disease.
Find out more about our Future Leader Reviews – they are an exclusive opportunity for early-career researchers who want to establish themselves in their field.
First author interviews
Catch up on our latest first author interviews to go behind the scenes of our latest research, find out more about the authors and hear from early-career researchers themselves how they’re finding life at the bench.
Retinal degeneration in Drosophila
Thank you to Elisabeth Knust and her team for their confocal image of a longitudinal section of an adult Drosophila retina, which brightens the cover of our latest issue. Read the research behind the cover.