Dolphin echolocation behaviour during active long-range target approaches
Financial support was provided by the US Office of Naval Research Code 32 (Mine Countermeasures, Acoustics Phenomenology & Modeling Group). M.L. and P.T.M. were funded by frame grants from the National Danish Research Council (Det Frie Forskningsråd) and by a Semper Ardens grant from the Carlsbe...
Published in: | Journal of Experimental Biology |
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Main Authors: | , , , , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
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2020
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Online Access: | http://hdl.handle.net/10023/19353 https://doi.org/10.1242/jeb.189217 http://jeb.biologists.org/lookup/doi/10.1242/jeb.189217.supplemental |
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ftstandrewserep:oai:research-repository.st-andrews.ac.uk:10023/19353 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
University of St Andrews: Digital Research Repository |
op_collection_id |
ftstandrewserep |
language |
English |
topic |
Biosonar Click packet Dtag Interclick interval Source level Toothed whale QH301 Biology Ecology Evolution Behavior and Systematics Physiology Aquatic Science Animal Science and Zoology Molecular Biology Insect Science NDAS QH301 |
spellingShingle |
Biosonar Click packet Dtag Interclick interval Source level Toothed whale QH301 Biology Ecology Evolution Behavior and Systematics Physiology Aquatic Science Animal Science and Zoology Molecular Biology Insect Science NDAS QH301 Ladegaard, Michael Mulsow, Jason Houser, Dorian S. Jensen, Frants Havmand Johnson, Mark Madsen, Peter Teglberg Finneran, James J. Dolphin echolocation behaviour during active long-range target approaches |
topic_facet |
Biosonar Click packet Dtag Interclick interval Source level Toothed whale QH301 Biology Ecology Evolution Behavior and Systematics Physiology Aquatic Science Animal Science and Zoology Molecular Biology Insect Science NDAS QH301 |
description |
Financial support was provided by the US Office of Naval Research Code 32 (Mine Countermeasures, Acoustics Phenomenology & Modeling Group). M.L. and P.T.M. were funded by frame grants from the National Danish Research Council (Det Frie Forskningsråd) and by a Semper Ardens grant from the Carlsberg Foundation. M.L.’s travel expenses were covered by grants from Augustinus Fonden and DAS-Fonden (Danish Acoustical Society, Dansk Akustisk Selskab). F.H.J. was funded by an AIAS-COFUND fellowship from Aarhus Institute of Advanced Studies under the EU's Seventh Framework Programme (Agreement No. 609033). Echolocating toothed whales generally adjust click intensity and rate according to target range to ensure that echoes from targets of interest arrive before a subsequent click is produced, presumably facilitating range estimation from the delay between clicks and returning echoes. However, this click-echo-click paradigm for the dolphin biosonar is mostly based on experiments with stationary animals echolocating fixed targets at ranges below ∼120 m. Therefore, we trained two bottlenose dolphins instrumented with a sound recording tag to approach a target from ranges up to 400 m and either touch the target (subject TRO) or detect a target orientation change (subject SAY). We show that free-swimming dolphins dynamically increase interclick interval (ICI) out to target ranges of ∼100 m. TRO consistently kept ICIs above the two-way travel time (TWTT) for target ranges shorter than ∼100 m, whereas SAY switched between clicking at ICIs above and below the TWTT for target ranges down to ∼25 m. Source levels changed on average by 17log10(target range), but with considerable variation for individual slopes (4.1 standard deviations for by-trial random effects), demonstrating that dolphins do not adopt a fixed automatic gain control matched to target range. At target ranges exceeding ∼100 m, both dolphins frequently switched to click packet production in which interpacket intervals exceeded the TWTT, but ICIs were shorter ... |
author2 |
University of St Andrews. Scottish Oceans Institute University of St Andrews. Bioacoustics group University of St Andrews. Sound Tags Group University of St Andrews. Sea Mammal Research Unit University of St Andrews. Marine Alliance for Science & Technology Scotland University of St Andrews. School of Biology |
format |
Article in Journal/Newspaper |
author |
Ladegaard, Michael Mulsow, Jason Houser, Dorian S. Jensen, Frants Havmand Johnson, Mark Madsen, Peter Teglberg Finneran, James J. |
author_facet |
Ladegaard, Michael Mulsow, Jason Houser, Dorian S. Jensen, Frants Havmand Johnson, Mark Madsen, Peter Teglberg Finneran, James J. |
author_sort |
Ladegaard, Michael |
title |
Dolphin echolocation behaviour during active long-range target approaches |
title_short |
Dolphin echolocation behaviour during active long-range target approaches |
title_full |
Dolphin echolocation behaviour during active long-range target approaches |
title_fullStr |
Dolphin echolocation behaviour during active long-range target approaches |
title_full_unstemmed |
Dolphin echolocation behaviour during active long-range target approaches |
title_sort |
dolphin echolocation behaviour during active long-range target approaches |
publishDate |
2020 |
url |
http://hdl.handle.net/10023/19353 https://doi.org/10.1242/jeb.189217 http://jeb.biologists.org/lookup/doi/10.1242/jeb.189217.supplemental |
genre |
toothed whale toothed whales |
genre_facet |
toothed whale toothed whales |
op_relation |
Journal of Experimental Biology Ladegaard , M , Mulsow , J , Houser , D S , Jensen , F H , Johnson , M , Madsen , P T & Finneran , J J 2019 , ' Dolphin echolocation behaviour during active long-range target approaches ' , Journal of Experimental Biology , vol. 222 , jeb189217 . https://doi.org/10.1242/jeb.189217 0022-0949 PURE: 257966858 PURE UUID: 9e15b632-bb8f-4379-8e51-2c0d2da9645d Scopus: 85060543398 PubMed: 30478155 WOS: 000457426400011 http://hdl.handle.net/10023/19353 https://doi.org/10.1242/jeb.189217 http://jeb.biologists.org/lookup/doi/10.1242/jeb.189217.supplemental |
op_rights |
Copyright © 2019. Published by The Company of Biologists Ltd. This work is made available online in accordance with the publisher’s policies. This is the final published version of the work, which was originally published at: https://doi.org/10.1242/jeb.189217 |
op_doi |
https://doi.org/10.1242/jeb.189217 |
container_title |
Journal of Experimental Biology |
_version_ |
1770273987438313472 |
spelling |
ftstandrewserep:oai:research-repository.st-andrews.ac.uk:10023/19353 2023-07-02T03:33:52+02:00 Dolphin echolocation behaviour during active long-range target approaches Ladegaard, Michael Mulsow, Jason Houser, Dorian S. Jensen, Frants Havmand Johnson, Mark Madsen, Peter Teglberg Finneran, James J. University of St Andrews. Scottish Oceans Institute University of St Andrews. Bioacoustics group University of St Andrews. Sound Tags Group University of St Andrews. Sea Mammal Research Unit University of St Andrews. Marine Alliance for Science & Technology Scotland University of St Andrews. School of Biology 2020-01-25 12 application/pdf http://hdl.handle.net/10023/19353 https://doi.org/10.1242/jeb.189217 http://jeb.biologists.org/lookup/doi/10.1242/jeb.189217.supplemental eng eng Journal of Experimental Biology Ladegaard , M , Mulsow , J , Houser , D S , Jensen , F H , Johnson , M , Madsen , P T & Finneran , J J 2019 , ' Dolphin echolocation behaviour during active long-range target approaches ' , Journal of Experimental Biology , vol. 222 , jeb189217 . https://doi.org/10.1242/jeb.189217 0022-0949 PURE: 257966858 PURE UUID: 9e15b632-bb8f-4379-8e51-2c0d2da9645d Scopus: 85060543398 PubMed: 30478155 WOS: 000457426400011 http://hdl.handle.net/10023/19353 https://doi.org/10.1242/jeb.189217 http://jeb.biologists.org/lookup/doi/10.1242/jeb.189217.supplemental Copyright © 2019. Published by The Company of Biologists Ltd. This work is made available online in accordance with the publisher’s policies. This is the final published version of the work, which was originally published at: https://doi.org/10.1242/jeb.189217 Biosonar Click packet Dtag Interclick interval Source level Toothed whale QH301 Biology Ecology Evolution Behavior and Systematics Physiology Aquatic Science Animal Science and Zoology Molecular Biology Insect Science NDAS QH301 Journal article 2020 ftstandrewserep https://doi.org/10.1242/jeb.189217 2023-06-13T18:29:19Z Financial support was provided by the US Office of Naval Research Code 32 (Mine Countermeasures, Acoustics Phenomenology & Modeling Group). M.L. and P.T.M. were funded by frame grants from the National Danish Research Council (Det Frie Forskningsråd) and by a Semper Ardens grant from the Carlsberg Foundation. M.L.’s travel expenses were covered by grants from Augustinus Fonden and DAS-Fonden (Danish Acoustical Society, Dansk Akustisk Selskab). F.H.J. was funded by an AIAS-COFUND fellowship from Aarhus Institute of Advanced Studies under the EU's Seventh Framework Programme (Agreement No. 609033). Echolocating toothed whales generally adjust click intensity and rate according to target range to ensure that echoes from targets of interest arrive before a subsequent click is produced, presumably facilitating range estimation from the delay between clicks and returning echoes. However, this click-echo-click paradigm for the dolphin biosonar is mostly based on experiments with stationary animals echolocating fixed targets at ranges below ∼120 m. Therefore, we trained two bottlenose dolphins instrumented with a sound recording tag to approach a target from ranges up to 400 m and either touch the target (subject TRO) or detect a target orientation change (subject SAY). We show that free-swimming dolphins dynamically increase interclick interval (ICI) out to target ranges of ∼100 m. TRO consistently kept ICIs above the two-way travel time (TWTT) for target ranges shorter than ∼100 m, whereas SAY switched between clicking at ICIs above and below the TWTT for target ranges down to ∼25 m. Source levels changed on average by 17log10(target range), but with considerable variation for individual slopes (4.1 standard deviations for by-trial random effects), demonstrating that dolphins do not adopt a fixed automatic gain control matched to target range. At target ranges exceeding ∼100 m, both dolphins frequently switched to click packet production in which interpacket intervals exceeded the TWTT, but ICIs were shorter ... Article in Journal/Newspaper toothed whale toothed whales University of St Andrews: Digital Research Repository Journal of Experimental Biology |