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Chevallay M, Guinet C, Goulet-Tran D, Jeanniard du Dot T. Sealing the deal - Antarctic fur seals' active hunting tactics to capture small evasive prey revealed by miniature sonar tags. J Exp Biol 2024; 227:jeb246937. [PMID: 38634142 DOI: 10.1242/jeb.246937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 04/04/2024] [Indexed: 04/19/2024]
Abstract
The ability of predators to adopt hunting tactics that minimise escape reactions from prey is crucial for efficient foraging, and depends on detection capabilities and locomotor performance of both predators and prey. Here, we investigated the efficiency of a small pinniped, the Antarctic fur seal (Arctocephalus gazella) at exploiting their small prey by describing for the first time their fine-scale predator-prey interactions. We compared these with those from another diving predator, the southern elephant seal (Mirounga leonina) that forage on the same prey type. We used data recorded by a newly developed sonar tag that combines active acoustics with ultrahigh-resolution movement sensors to study simultaneously the fine-scale behaviour of both Antarctic fur seals and prey during predator-prey interactions in more than 1200 prey capture events for eight female Antarctic fur seals. Our results showed that Antarctic fur seals and their prey detect each other at the same time, i.e. 1-2 s before the strike, forcing Antarctic fur seals to display reactive fast-moving chases to capture their prey. In contrast, southern elephant seals detect their prey up to 10 s before the strike, allowing them to approach their prey stealthily without triggering an escape reaction. The active hunting tactics used by Antarctic fur seals is probably very energy consuming compared with the stalking tactics used by southern elephant seals but might be compensated for by the consumption of faster-moving larger prey. We suggest that differences in manoeuvrability, locomotor performance and detection capacities and in pace of life between Antarctic fur seals and southern elephant seals might explain these differences in hunting styles.
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Affiliation(s)
- Mathilde Chevallay
- Centre d'Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, 79360 Villiers-en-Bois, France
| | - Christophe Guinet
- Centre d'Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, 79360 Villiers-en-Bois, France
| | - Didier Goulet-Tran
- Centre d'Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, 79360 Villiers-en-Bois, France
| | - Tiphaine Jeanniard du Dot
- Centre d'Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, 79360 Villiers-en-Bois, France
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2
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Denk M, McLellan W, Pabst DA, Rommel S, Keenan T, Sharp S, Niemeyer M, Hunter N, Block G, Nelson N, Harms C, Thornton S, Costidis A, Moore M. Melon and rostral muscle morphology of Gervais' beaked whale (Mesoplodon europaeus): Alternating patterns of bilateral asymmetry. Anat Rec (Hoboken) 2024; 307:633-657. [PMID: 37548999 DOI: 10.1002/ar.25301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 07/08/2023] [Accepted: 07/20/2023] [Indexed: 08/08/2023]
Abstract
Toothed whales utilize specialized nasal structures such as the lipid-rich melon to produce sound and propagate it into the aquatic environment. Very little nasal morphology of mesoplodont beaked whales has been described in the literature, and the anatomy of the melon and associated musculature of Gervais' beaked whale (Mesoplodon europaeus) remains undescribed. Heads of three (n = 3) Gervais' beaked whales were examined in detail via dissection as well as computed tomography (CT) and magnetic resonance imaging (MRI). Two additional Gervais' beaked whale individuals (n = 2) were studied via archived CT and MRI scans. Representative transverse dissection sections of the melon were processed for polarized light imaging to verify the presence of tendons inserting into the melon tissue. Three-dimensional (3D) CT reconstructions of the melon, rostral muscles, and associated structures were performed to assess morphology and spatial relationships. In all individuals, the melon's main body demonstrated a bilaterally asymmetrical, curvilinear geometry. This curvilinear shape was defined by a pattern of alternating asymmetry in the medial rostral muscles that projected into the melon's tissue. In transverse polarized light imaging, a network of tendons originating from these asymmetrical rostral muscle projections was observed permeating the melon's lipid tissue. This curvilinear melon morphology and associated asymmetrical musculature suggest a means of lengthening the lipid pathway within a relatively short dimensional footprint. In addition, the species-specific arrangement of muscular projections suggests complex fine-tuning of the melon's geometry during echolocation. Further studies may lend additional insight into the function of this unusual melon morphology.
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Affiliation(s)
- Michael Denk
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA
- Cape May Whale Watch and Research Center, Cape May, New Jersey, USA
| | - William McLellan
- Department of Biology and Marine Biology, University of North Carolina Wilmington USA, Wilmington, North Carolina, USA
| | - D Ann Pabst
- Department of Biology and Marine Biology, University of North Carolina Wilmington USA, Wilmington, North Carolina, USA
| | - Sentiel Rommel
- Department of Biology and Marine Biology, University of North Carolina Wilmington USA, Wilmington, North Carolina, USA
| | - Tiffany Keenan
- Department of Biology and Marine Biology, University of North Carolina Wilmington USA, Wilmington, North Carolina, USA
| | - Sarah Sharp
- International Fund for Animal Welfare, Yarmouth Port, Massachusetts, USA
| | - Misty Niemeyer
- International Fund for Animal Welfare, Yarmouth Port, Massachusetts, USA
| | - Nicole Hunter
- International Fund for Animal Welfare, Yarmouth Port, Massachusetts, USA
| | - Gary Block
- Ocean State Veterinary Specialists, East Greenwich, Rhode Island, USA
| | - Nathan Nelson
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | - Craig Harms
- Department of Molecular Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, North Carolina, USA
| | - Steven Thornton
- Department of Biology and Marine Biology, University of North Carolina Wilmington USA, Wilmington, North Carolina, USA
| | | | - Michael Moore
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, USA
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3
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Abildtrup Nielsen N, Dawson SM, Torres Ortiz S, Wahlberg M, Martin MJ. Hector's dolphins (Cephalorhynchus hectori) produce both narrowband high-frequency and broadband acoustic signals. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2024; 155:1437-1450. [PMID: 38364047 DOI: 10.1121/10.0024820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 01/25/2024] [Indexed: 02/18/2024]
Abstract
Odontocetes produce clicks for echolocation and communication. Most odontocetes are thought to produce either broadband (BB) or narrowband high-frequency (NBHF) clicks. Here, we show that the click repertoire of Hector's dolphin (Cephalorhynchus hectori) comprises highly stereotypical NBHF clicks and far more variable broadband clicks, with some that are intermediate between these two categories. Both NBHF and broadband clicks were made in trains, buzzes, and burst-pulses. Most clicks within click trains were typical NBHF clicks, which had a median centroid frequency of 130.3 kHz (median -10 dB bandwidth = 29.8 kHz). Some, however, while having only marginally lower centroid frequency (median = 123.8 kHz), had significant energy below 100 kHz and approximately double the bandwidth (median -10 dB bandwidth = 69.8 kHz); we refer to these as broadband. Broadband clicks in buzzes and burst-pulses had lower median centroid frequencies (120.7 and 121.8 kHz, respectively) compared to NBHF buzzes and burst-pulses (129.5 and 130.3 kHz, respectively). Source levels of NBHF clicks, estimated by using a drone to measure ranges from a single hydrophone and by computing time-of-arrival differences at a vertical hydrophone array, ranged from 116 to 171 dB re 1 μPa at 1 m, whereas source levels of broadband clicks, obtained from array data only, ranged from 138 to 184 dB re 1 μPa at 1 m. Our findings challenge the grouping of toothed whales as either NBHF or broadband species.
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Affiliation(s)
- Nicoline Abildtrup Nielsen
- Marine Biological Research Center, Department of Biology, University of Southern Denmark, 5300 Kerteminde, Denmark
| | - Stephen M Dawson
- Department of Marine Science, University of Otago, Dunedin 9054, New Zealand
| | - Sara Torres Ortiz
- Marine Biological Research Center, Department of Biology, University of Southern Denmark, 5300 Kerteminde, Denmark
| | - Magnus Wahlberg
- Marine Biological Research Center, Department of Biology, University of Southern Denmark, 5300 Kerteminde, Denmark
| | - Morgan J Martin
- Center for Marine Acoustics, Bureau of Ocean Energy Management, Sterling, Virginia 20166, USA
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4
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Mishima Y, Matsuo I, Karasawa Y, Ishii M, Morisaka T. Directional and amplitude characteristics of pulsed call sequences in captive free-swimming Pacific white-sided dolphins (Lagenorhynchus obliquidens). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 154:2974-2987. [PMID: 37947396 DOI: 10.1121/10.0022377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 10/24/2023] [Indexed: 11/12/2023]
Abstract
We investigated the directional properties and gain control of a pulsed call sequence that functions as a contact call in Pacific white-sided dolphins (Lagenorhynchus obliquidens). The pulsed call sequences were stereotyped patterns composed of three or more pulsed call elements and were collected from two dolphins, separated into adjacent pools, and allowed to swim freely. Eight hydrophones and an overhead camera were used to determine the positions and directions of the participants. The mean peak frequency and source levels were 8.4 ± 4.4 (standard deviation)-18.7 ± 12.7 kHz and 160.8 ± 3.8 to 176.4 ± 7.9 dB re 1 μPa (peak-to-peak), respectively, depending on the element types. The elements were omnidirectional, with mean directivity index of 0.9 ± 3.4 dB. The dolphins produced sequences, regardless of their relative position and direction to the lattice, leading to the adjacent pool where the conspecific was housed. They increased the amplitude by 6.5 ± 4.6 dB as the distance from the caller to an arbitrary point in the adjacent pool doubled. These results suggest that callers broadcast pulsed call sequences in a wide direction to reach dispersed conspecifics. However, they can adjust the acoustic active space by controlling the source levels.
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Affiliation(s)
- Yuka Mishima
- Department of Marine Resources and Energy, Tokyo University of Marine Science and Technology, 4-5-7, Konan, Minato-ku, Tokyo, 108-8477, Japan
| | - Ikuo Matsuo
- Department of Information Science, Tohoku Gakuin University, 2-1-1 Tenjinzawa, Izumi-ku, Sendai, 981-3193, Japan
| | - Yuu Karasawa
- Izu Mito Sea Paradise, 3-1, Nagahama, Uchiura, Numazu-shi, Shizuoka, 410-0295, Japan
| | - Marina Ishii
- Graduate School of Marine Science and Technology, Tokyo University of Marine Science and Technology, 4-5-7, Konan, Minato-ku, Tokyo, 108-8477, Japan
| | - Tadamichi Morisaka
- Cetacean Research Center, Graduate School of Bioresources, Mie University, 1577, Kurimamachiya-cho, Tsu-shi, Mie, 514-8507, Japan
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5
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Chevallay M, Goulet P, Madsen PT, Campagna J, Campagna C, Guinet C, Johnson MP. Large sensory volumes enable Southern elephant seals to exploit sparse deep-sea prey. Proc Natl Acad Sci U S A 2023; 120:e2307129120. [PMID: 37844247 PMCID: PMC10614626 DOI: 10.1073/pnas.2307129120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Accepted: 09/08/2023] [Indexed: 10/18/2023] Open
Abstract
The ability of echolocating toothed whales to detect and classify prey at long ranges enables efficient searching and stalking of sparse prey in these time-limited dives. However, nonecholocating deep-diving seals such as elephant seals appear to have much less sensory advantage over their prey. Both elephant seals and their prey rely on visual and hydrodynamic cues that may be detectable only at short ranges in the deep ocean, leading us to hypothesize that elephant seals must adopt a less efficient reactive mode of hunting that requires high prey densities. To test that hypothesis, we deployed high-resolution sonar and movement tags on 25 females to record simultaneous predator and prey behavior during foraging interactions. We demonstrate that elephant seals have a sensory advantage over their prey that allows them to potentially detect prey 5 to 10 s before striking. The corresponding prey detection ranges of 7 to 17 m enable stealthy approaches and prey-specific capture tactics. In comparison, prey react at a median range of 0.7 m, close to the neck extension range of striking elephant seals. Estimated search swathes of 150 to 900 m2 explain how elephant seals can locate up to 2,000 prey while swimming more than 100 km per day. This efficient search capability allows elephant seals to subsist on prey densities that are consonant with the deep scattering layer resources estimated by hydroacoustic surveys but which are two orders of magnitude lower than the prey densities needed by a reactive hunter.
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Affiliation(s)
- Mathilde Chevallay
- Centre d’Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, Villiers-en-Bois79360, France
| | - Pauline Goulet
- Centre d’Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, Villiers-en-Bois79360, France
| | | | - Julieta Campagna
- Centro Nacional Patagónico, Centro Científico Tecnológico del Consejo Nacional de Investigaciones Científicas y Técnicas, Puerto Madryn9120, Argentina
| | | | - Christophe Guinet
- Centre d’Etudes Biologiques de Chizé, Centre National de la Recherche Scientifique, Villiers-en-Bois79360, France
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Laeta M, Oliveira JA, Siciliano S, Lambert O, Jensen FH, Galatius A. Cranial asymmetry in odontocetes: a facilitator of sonic exploration? ZOOLOGY 2023; 160:126108. [PMID: 37633185 DOI: 10.1016/j.zool.2023.126108] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Revised: 07/31/2023] [Accepted: 08/04/2023] [Indexed: 08/28/2023]
Abstract
Directional cranial asymmetry is an intriguing condition that has evolved in all odontocetes which has mostly been associated with sound production for echolocation. In this study, we investigated how cranial asymmetry varies across odontocete species both in terms of quality (i.e., shape), and quantity (magnitude of deviation from symmetry). We investigated 72 species across all ten families of Odontoceti using two-dimensional geometric morphometrics. The average asymmetric shape was largely consistent across odontocetes - the rostral tip, maxillae, antorbital notches and braincase, as well as the suture crest between the frontal and interparietal bones were displaced to the right, whereas the nasal septum and premaxillae showed leftward shifts, in concert with an enlargement of the right premaxilla and maxilla. A clear phylogenetic signal related to asymmetric shape variation was identified across odontocetes using squared-change parsimony. The magnitude of asymmetry was widely variable across Odontoceti, with greatest asymmetry in Kogiidae, Monodontidae and Globicephalinae, followed by Physeteridae, Platanistidae and Lipotidae, while the asymmetry was lowest in Lissodelphininae, Phocoenidae, Iniidae and Pontoporiidae. Ziphiidae presented a wide spectrum of asymmetry. Generalized linear models explaining magnitude of asymmetry found associations with click source level while accounting for cranial size. Using phylogenetic generalized least squares, we reconfirm that source level and centroid size significantly predict the level of cranial asymmetry, with more asymmetric marine taxa generally consisting of bigger species emitting higher output sonar signal, i.e. louder sounds. Both characteristics theoretically support foraging at depth, the former by allowing extended diving and the latter being adaptive for prey detection at longer distances. Thus, cranial asymmetry seems to be an evolutionary pathway that allows odontocetes to devote more space for sound-generating structures associated with echolocation and thus increases biosonar search range and foraging efficiency beyond simple phylogenetic scaling predictions.
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Affiliation(s)
- Maíra Laeta
- Setor de Mastozoologia, Departamento de Vertebrados, Museu Nacional/Universidade Federal do Rio de Janeiro, 20941-160 Rio de Janeiro, RJ, Brazil.
| | - João A Oliveira
- Setor de Mastozoologia, Departamento de Vertebrados, Museu Nacional/Universidade Federal do Rio de Janeiro, 20941-160 Rio de Janeiro, RJ, Brazil
| | - Salvatore Siciliano
- Departamento de Ciências Biológicas, Escola Nacional de Saúde Pública Sergio Arouca/Fiocruz, 21040-360 Rio de Janeiro, RJ, Brazil; Grupo de Estudos de Mamíferos Marinhos da Região dos Lagos (GEMM-Lagos), Rua São José, 1.260, Praia Seca, 28970-000 Araruama, RJ, Brazil
| | - Olivier Lambert
- D.O. Terre et Histoire de la Vie, Institut royal des Sciences naturelles de Belgique, 1000 Brussels, Belgium
| | - Frants H Jensen
- Section for Marine Mammal Research, Department of Ecoscience, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark; Biology Department, Woods Hole Oceanographic Institution, 266 Woods Hole Rd, MA 02543, USA; Biology Department, Syracuse University, 107 College Place, Syracuse, NY 13244, USA
| | - Anders Galatius
- Section for Marine Mammal Research, Department of Ecoscience, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark.
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Macaulay JDJ, Rojano-Doñate L, Ladegaard M, Tougaard J, Teilmann J, Marques TA, Siebert U, Madsen PT. Implications of porpoise echolocation and dive behaviour on passive acoustic monitoring. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 154:1982-1995. [PMID: 37782119 DOI: 10.1121/10.0021163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Accepted: 09/06/2023] [Indexed: 10/03/2023]
Abstract
Harbour porpoises are visually inconspicuous but highly soniferous echolocating marine predators that are regularly studied using passive acoustic monitoring (PAM). PAM can provide quality data on animal abundance, human impact, habitat use, and behaviour. The probability of detecting porpoise clicks within a given area (P̂) is a key metric when interpreting PAM data. Estimates of P̂ can be used to determine the number of clicks per porpoise encounter that may have been missed on a PAM device, which, in turn, allows for the calculation of abundance and ideally non-biased comparison of acoustic data between habitats and time periods. However, P̂ is influenced by several factors, including the behaviour of the vocalising animal. Here, the common implicit assumption that changes in animal behaviour have a negligible effect on P̂ between different monitoring stations or across time is tested. Using a simulation-based approach informed by acoustic biologging data from 22 tagged harbour porpoises, it is demonstrated that porpoise behavioural states can have significant (up to 3× difference) effects on P̂. Consequently, the behavioural state of the animals must be considered in analysis of animal abundance to avoid substantial over- or underestimation of the true abundance, habitat use, or effects of human disturbance.
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Affiliation(s)
- Jamie Donald John Macaulay
- Department of Biology-Zoophysiology, Aarhus University, C. F. Møllers Allé 3, building 1131, 8000 Aarhus C, Denmark
| | - Laia Rojano-Doñate
- Department of Biology-Zoophysiology, Aarhus University, C. F. Møllers Allé 3, building 1131, 8000 Aarhus C, Denmark
| | - Michael Ladegaard
- Department of Biology-Zoophysiology, Aarhus University, C. F. Møllers Allé 3, building 1131, 8000 Aarhus C, Denmark
| | - Jakob Tougaard
- Department of Ecoscience-Marine Mammal Research, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Jonas Teilmann
- Department of Ecoscience-Marine Mammal Research, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Tiago A Marques
- Centre for Research into Ecological and Environmental Modelling, University of St. Andrews, St. Andrews, Scotland, United Kingdom
| | - Ursula Siebert
- Department of Ecoscience-Marine Mammal Research, Aarhus University, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Peter Teglberg Madsen
- Department of Biology-Zoophysiology, Aarhus University, C. F. Møllers Allé 3, building 1131, 8000 Aarhus C, Denmark
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8
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Wei C, Houser D, Erbe C, Mátrai E, Ketten DR, Finneran JJ. Does rotation increase the acoustic field of view? Comparative models based on CT data of a live dolphin versus a dead dolphin. BIOINSPIRATION & BIOMIMETICS 2023; 18:035006. [PMID: 36917857 DOI: 10.1088/1748-3190/acc43d] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2022] [Accepted: 03/14/2023] [Indexed: 06/18/2023]
Abstract
Rotational behaviour has been observed when dolphins track or detect targets, however, its role in echolocation is unknown. We used computed tomography data of one live and one recently deceased bottlenose dolphin, together with measurements of the acoustic properties of head tissues, to perform acoustic property reconstruction. The anatomical configuration and acoustic properties of the main forehead structures between the live and deceased dolphins were compared. Finite element analysis (FEA) was applied to simulate the generation and propagation of echolocation clicks, to compute their waveforms and spectra in both near- and far-fields, and to derive echolocation beam patterns. Modelling results from both the live and deceased dolphins were in good agreement with click recordings from other, live, echolocating individuals. FEA was also used to estimate the acoustic scene experienced by a dolphin rotating 180° about its longitudinal axis to detect fish in the far-field at elevation angles of -20° to 20°. The results suggest that the rotational behaviour provides a wider insonification area and a wider receiving area. Thus, it may provide compensation for the dolphin's relatively narrow biosonar beam, asymmetries in sound reception, and constraints on the pointing direction that are limited by head movement. The results also have implications for examining the accuracy of FEA in acoustic simulations using recently deceased specimens.
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Affiliation(s)
- Chong Wei
- Centre for Marine Science and Technology, Curtin University, Perth, WA 6102, Australia
| | - Dorian Houser
- National Marine Mammal Foundation, 2240 Shelter Island Drive, #200, San Diego, CA 92106, United States of America
| | - Christine Erbe
- Centre for Marine Science and Technology, Curtin University, Perth, WA 6102, Australia
| | - Eszter Mátrai
- Research Department, Ocean Park, Hong Kong, People's Republic of China
| | - Darlene R Ketten
- Department of Biomedical Engineering, Boston University, Boston, MA 02215, United States of America
| | - James J Finneran
- United States Navy Marine Mammal Program, Naval Information Warfare Center Pacific Code 56710, 53560 Hull Street, San Diego, CA 92152, United States of America
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9
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Bakkeren C, Ladegaard M, Hansen KA, Wahlberg M, Madsen PT, Rojano-Doñate L. Visual deprivation induces a stronger dive response in a harbor porpoise. iScience 2023; 26:106204. [PMID: 36876128 PMCID: PMC9982314 DOI: 10.1016/j.isci.2023.106204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 11/15/2022] [Accepted: 02/10/2023] [Indexed: 02/16/2023] Open
Abstract
The dive response allows marine mammals to perform prolonged breath-hold dives to access rich marine prey resources. Via dynamic adjustments of peripheral vasoconstriction and bradycardia, oxygen consumption can be tailored to breath-hold duration, depth, exercise, and even expectations during dives. By investigating the heart rate of a trained harbor porpoise during a two-alternative forced choice task, where the animal is either acoustically masked or blindfolded, we test the hypothesis that sensory deprivation will lead to a stronger dive response to conserve oxygen when facing a more uncertain and smaller sensory umwelt. We show that the porpoise halves its diving heart rate (from 55 to 25 bpm) when blindfolded but presents no change in heart rate during masking of its echolocation. Therefore, visual stimuli may matter more to echolocating toothed whales than previously assumed, and sensory deprivation can be a major driver of the dive response, possibly as an anti-predator measure.
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Affiliation(s)
- Ciska Bakkeren
- Zoophysiology, Department of Biology, Aarhus University, Building 1131, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
| | - Michael Ladegaard
- Zoophysiology, Department of Biology, Aarhus University, Building 1131, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
| | - Kirstin Anderson Hansen
- Department of Biology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark.,Fjord&Bælt, Margrethes Plads 1, 5300 Kerteminde, Denmark
| | - Magnus Wahlberg
- Department of Biology, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
| | - Peter Teglberg Madsen
- Zoophysiology, Department of Biology, Aarhus University, Building 1131, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
| | - Laia Rojano-Doñate
- Zoophysiology, Department of Biology, Aarhus University, Building 1131, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
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10
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Madsen PT, Siebert U, Elemans CPH. Toothed whales use distinct vocal registers for echolocation and communication. Science 2023; 379:928-933. [PMID: 36862790 DOI: 10.1126/science.adc9570] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Echolocating toothed whales (odontocetes) capture fast-moving prey in dark marine environments, which critically depends on their ability to generate powerful, ultrasonic clicks. How their supposedly air-driven sound source can produce biosonar clicks at depths of >1000 meters, while also producing rich vocal repertoires to mediate complex social communication, remains unknown. We show that odontocetes possess a sound production system based on air driven through nasal passages that is functionally analogous to laryngeal and syringeal sound production. Tissue vibration in different registers produces distinct echolocation and communication signals across all major odontocete clades, and thus provides a physiological basis for classifying their vocal repertoires. The vocal fry register is used by species from porpoises to sperm whales for generating powerful, highly air-efficient echolocation clicks.
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Affiliation(s)
- Peter T Madsen
- Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark
| | - Ursula Siebert
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, 25761 Büsum, Germany
| | - Coen P H Elemans
- Sound Communication and Behavior Group, Department of Biology, University of Southern Denmark, 5230 Odense M, Denmark
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11
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Zhao L, Giorli G, Caruso F, Dong L, Gong Z, Lin M, Li S. Echolocation clicks of free-ranging Indo-Pacific finless porpoises (Neophocaena phocaenoides) in Hainan waters. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 153:1934. [PMID: 37002078 DOI: 10.1121/10.0017655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 03/06/2023] [Indexed: 05/18/2023]
Abstract
The echolocation clicks of free-ranging Indo-Pacific finless porpoises (IPFPs, Neophocaena phocaenoides) have been rarely studied in the wild. This paper aims at describing the echolocation-click characteristics of IPFPs and examining whether IPFPs adapt their sonar system to the habitats in Hainan waters, China. The echolocation clicks were recorded using a 13 elements star-shaped array of hydrophones. A total of 65 on-axis clicks were identified and analyzed. IPFPs use echolocation clicks with a source level (SL) of 158 ± 9 dB re: 1 μPa peak-peak, mean peak, and centroid frequency of 134 ± 3 kHz, -3 dB bandwidth of 14 ± 2 kHz and produce at inter-click intervals of 104 ± 51 ms. The results relative to other porpoises show that finless porpoises in Hainan waters produce clicks with moderate SLs and high peak frequency. These results could be useful in detecting the presence and estimating the density of IPFPs during passive acoustic monitoring in the study area and serve to shed light on the interpopulation variation of click characteristics of finless porpoises as well.
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Affiliation(s)
- Likun Zhao
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences (CAS), Sanya, 572000, China
| | - Giacomo Giorli
- National Institute of Water and Atmospheric Research, Coasts and Oceans, 301 Evans Bay Parade, Greta Point, Wellington, 6021, New Zealand
| | - Francesco Caruso
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences (CAS), Sanya, 572000, China
| | - Lijun Dong
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences (CAS), Sanya, 572000, China
| | - Zining Gong
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences (CAS), Sanya, 572000, China
| | - Mingli Lin
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences (CAS), Sanya, 572000, China
| | - Songhai Li
- Marine Mammal and Marine Bioacoustics Laboratory, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences (CAS), Sanya, 572000, China
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12
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Ecomorphology of toothed whales (Cetacea, Odontoceti) as revealed by 3D skull geometry. J MAMM EVOL 2023. [DOI: 10.1007/s10914-022-09642-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
AbstractExtant odontocetes (toothed whales) exhibit differences in body size and brain mass, biosonar mode, feeding strategies, and diving and habitat adaptations. Strong selective pressures associated with these factors have likely contributed to the morphological diversification of their skull. Here, we used 3D landmark geometric morphometric data from the skulls of 60 out of ~ 72 extant odontocete species and a well-supported phylogenetic tree to test whether size and shape variation are associated with ecological adaptations at an interspecific scale. Odontocete skull morphology exhibited a significant phylogenetic signal, with skull size showing stronger signal than shape. After accounting for phylogeny, significant associations were detected between skull size and biosonar mode, body length, brain and body mass, maximum and minimum prey size, and maximum peak frequency. Brain mass was also strongly correlated with skull shape together with surface temperature and average and minimum prey size. When asymmetric and symmetric components of shape were analysed separately, a significant correlation was detected between sea surface temperature and both symmetric and asymmetric components of skull shape, and between diving ecology and the asymmetric component. Skull shape variation of odontocetes was strongly influenced by evolutionary allometry but most of the associations with ecological variables were not supported after phylogenetic correction. This suggests that ecomorphological feeding adaptations vary more between, rather than within, odontocete families, and functional anatomical patterns across odontocete clades are canalised by size constraints.
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13
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Lanzetti A, Coombs EJ, Portela Miguez R, Fernandez V, Goswami A. The ontogeny of asymmetry in echolocating whales. Proc Biol Sci 2022; 289:20221090. [PMID: 35919995 PMCID: PMC9346347 DOI: 10.1098/rspb.2022.1090] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Accepted: 07/12/2022] [Indexed: 12/14/2022] Open
Abstract
Extreme asymmetry of the skull is one of the most distinctive traits that characterizes toothed whales (Odontoceti, Cetacea). The origin and function of cranial asymmetry are connected to the evolution of echolocation, the ability to use high-frequency sounds to navigate the surrounding environment. Although this novel phenotype must arise through changes in cranial development, the ontogeny of cetacean asymmetry has never been investigated. Here we use three-dimensional geometric morphometrics to quantify the changes in degree of asymmetry and skull shape during prenatal and postnatal ontogeny for five genera spanning odontocete diversity (oceanic dolphins, porpoises and beluga). Asymmetry in early ontogeny starts low and tracks phylogenetic relatedness of taxa. Distantly related taxa that share aspects of their ecology overwrite these initial differences via heterochronic shifts, ultimately converging on comparable high levels of skull asymmetry. Porpoises maintain low levels of asymmetry into maturity and present a decelerated rate of growth, probably retained from the ancestral condition. Ancestral state reconstruction of allometric trajectories demonstrates that both paedomorphism and peramorphism contribute to cranial shape diversity across odontocetes. This study provides a striking example of how divergent developmental pathways can produce convergent ecological adaptations, even for some of the most unusual phenotypes exhibited among vertebrates.
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Affiliation(s)
- Agnese Lanzetti
- Department of Life Sciences, Natural History Museum, Cromwell Road, Kensington, London SW7 5BD, UK
| | - Ellen J. Coombs
- Department of Vertebrate Zoology, Smithsonian National Museum of Natural History, PO Box 37012, MRC 108, Washington, DC 20013-7012, USA
| | - Roberto Portela Miguez
- Department of Life Sciences, Natural History Museum, Cromwell Road, Kensington, London SW7 5BD, UK
| | | | - Anjali Goswami
- Department of Life Sciences, Natural History Museum, Cromwell Road, Kensington, London SW7 5BD, UK
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14
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Cohen RE, Frasier KE, Baumann-Pickering S, Wiggins SM, Rafter MA, Baggett LM, Hildebrand JA. Identification of western North Atlantic odontocete echolocation click types using machine learning and spatiotemporal correlates. PLoS One 2022; 17:e0264988. [PMID: 35324943 PMCID: PMC8946748 DOI: 10.1371/journal.pone.0264988] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 02/21/2022] [Indexed: 11/18/2022] Open
Abstract
A combination of machine learning and expert analyst review was used to detect odontocete echolocation clicks, identify dominant click types, and classify clicks in 32 years of acoustic data collected at 11 autonomous monitoring sites in the western North Atlantic between 2016 and 2019. Previously-described click types for eight known odontocete species or genera were identified in this data set: Blainville's beaked whales (Mesoplodon densirostris), Cuvier's beaked whales (Ziphius cavirostris), Gervais' beaked whales (Mesoplodon europaeus), Sowerby's beaked whales (Mesoplodon bidens), and True's beaked whales (Mesoplodon mirus), Kogia spp., Risso's dolphin (Grampus griseus), and sperm whales (Physeter macrocephalus). Six novel delphinid echolocation click types were identified and named according to their median peak frequencies. Consideration of the spatiotemporal distribution of these unidentified click types, and comparison to historical sighting data, enabled assignment of the probable species identity to three of the six types, and group identity to a fourth type. UD36, UD26, and UD28 were attributed to Risso's dolphin (G. griseus), short-finned pilot whale (G. macrorhynchus), and short-beaked common dolphin (D. delphis), respectively, based on similar regional distributions and seasonal presence patterns. UD19 was attributed to one or more species in the subfamily Globicephalinae based on spectral content and signal timing. UD47 and UD38 represent distinct types for which no clear spatiotemporal match was apparent. This approach leveraged the power of big acoustic and big visual data to add to the catalog of known species-specific acoustic signals and yield new inferences about odontocete spatiotemporal distribution patterns. The tools and call types described here can be used for efficient analysis of other existing and future passive acoustic data sets from this region.
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Affiliation(s)
- Rebecca E. Cohen
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
- * E-mail:
| | - Kaitlin E. Frasier
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
| | - Simone Baumann-Pickering
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
| | - Sean M. Wiggins
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
| | - Macey A. Rafter
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
| | - Lauren M. Baggett
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
| | - John A. Hildebrand
- Scripps Institution of Oceanography, University of California San Diego, La Jolla, California, United States of America
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15
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Vicari D, Sabin RC, Brown RP, Lambert O, Bianucci G, Meloro C. Skull morphological variation in a British stranded population of false killer whale (Pseudorca crassidens): a three-dimensional geometric morphometric approach. CAN J ZOOL 2022. [DOI: 10.1139/cjz-2021-0112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The false killer whale (Pseudorca crassidens (Owen, 1846)) is a globally distributed delphinid that shows geographical differentiation in its skull morphology. We explored cranial morphological variation in a sample of 85 skulls belonging to a mixed sex population stranded in the Moray Firth, Scotland, in 1927. A three-dimensional digitizer (Microscribe 2GX) was used to record 37 anatomical landmarks on the cranium and 25 on the mandible to investigate size and shape variation and to explore sexual dimorphism using geometric morphometric. Males showed greater overall skull size than females, whereas no sexual dimorphism could be identified in cranial and mandibular shape. Allometric skull changes occurred in parallel for both males and females, supporting the lack of sexual shape dimorphism for this particular sample. Also, fluctuating asymmetry did not differ between crania of males and females. This study confirms the absence of sexual shape dimorphism and the presence of a sexual size dimorphism in this false killer whale population.
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Affiliation(s)
- Deborah Vicari
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Biological and Environmental Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK
| | - Richard C. Sabin
- Department of Life Sciences, The Natural History Museum, Cromwell Road, South Kensington, London SW7 5BD, UK
| | - Richard P. Brown
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Biological and Environmental Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK
| | - Olivier Lambert
- D.O. Terre et Histoire de la Vie, Institut Royal des Sciences Naturelles de Belgique, 1000 Brussels, Belgium
| | - Giovanni Bianucci
- Dipartimento di Scienze della Terra, Università di Pisa, 56126 Pisa, Italy
| | - Carlo Meloro
- Research Centre in Evolutionary Anthropology and Palaeoecology, School of Biological and Environmental Sciences, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK
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16
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Ladegaard M, Macaulay J, Simon M, Laidre KL, Mitseva A, Videsen S, Pedersen MB, Tougaard J, Madsen PT. Soundscape and ambient noise levels of the Arctic waters around Greenland. Sci Rep 2021; 11:23360. [PMID: 34862381 PMCID: PMC8642542 DOI: 10.1038/s41598-021-02255-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 10/27/2021] [Indexed: 11/09/2022] Open
Abstract
A longer Arctic open water season is expected to increase underwater noise levels due to anthropogenic activities such as shipping, seismic surveys, sonar, and construction. Many Arctic marine mammal species depend on sound for communication, navigation, and foraging, therefore quantifying underwater noise levels is critical for documenting change and providing input to management and legislation. Here we present long-term underwater sound recordings from 26 deployments around Greenland from 2011 to 2020. Ambient noise was analysed in third octave and decade bands and further investigated using generic detectors searching for tonal and transient sounds. Ambient noise levels partly overlap with previous Arctic observations, however we report much lower noise levels than previously documented, specifically for Melville Bay and the Greenland Sea. Consistent seasonal noise patterns occur in Melville Bay, Baffin Bay and Greenland Sea, with noise levels peaking in late summer and autumn correlating with open water periods and seismic surveys. These three regions also had similar tonal detection patterns that peaked in May/June, likely due to bearded seal vocalisations. Biological activity was more readily identified using detectors rather than band levels. We encourage additional research to quantify proportional noise contributions from geophysical, biological, and anthropogenic sources in Arctic waters.
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Affiliation(s)
- Michael Ladegaard
- Zoophysiology, Department of Biology, Aarhus University, Aarhus, Denmark.
| | - Jamie Macaulay
- Zoophysiology, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Malene Simon
- Greenland Institute of Natural Resources, Nuuk, Greenland
- Greenland Climate Research Centre, Greenland Institute of Natural Resources, Nuuk, Greenland
| | - Kristin L Laidre
- Greenland Institute of Natural Resources, Nuuk, Greenland
- Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle, WA, USA
| | | | - Simone Videsen
- Zoophysiology, Department of Biology, Aarhus University, Aarhus, Denmark
| | | | - Jakob Tougaard
- Marine Mammal Research, Department of Ecoscience, Aarhus University, Roskilde, Denmark
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17
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Jones TK, Allen KM, Moss CF. Communication with self, friends and foes in active-sensing animals. J Exp Biol 2021; 224:273391. [PMID: 34752625 DOI: 10.1242/jeb.242637] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Animals that rely on electrolocation and echolocation for navigation and prey detection benefit from sensory systems that can operate in the dark, allowing them to exploit sensory niches with few competitors. Active sensing has been characterized as a highly specialized form of communication, whereby an echolocating or electrolocating animal serves as both the sender and receiver of sensory information. This characterization inspires a framework to explore the functions of sensory channels that communicate information with the self and with others. Overlapping communication functions create challenges for signal privacy and fidelity by leaving active-sensing animals vulnerable to eavesdropping, jamming and masking. Here, we present an overview of active-sensing systems used by weakly electric fish, bats and odontocetes, and consider their susceptibility to heterospecific and conspecific jamming signals and eavesdropping. Susceptibility to interference from signals produced by both conspecifics and prey animals reduces the fidelity of electrolocation and echolocation for prey capture and foraging. Likewise, active-sensing signals may be eavesdropped, increasing the risk of alerting prey to the threat of predation or the risk of predation to the sender, or drawing competition to productive foraging sites. The evolutionary success of electrolocating and echolocating animals suggests that they effectively counter the costs of active sensing through rich and diverse adaptive behaviors that allow them to mitigate the effects of competition for signal space and the exploitation of their signals.
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Affiliation(s)
- Te K Jones
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Kathryne M Allen
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Cynthia F Moss
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA
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18
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Zahn MJ, Laidre KL, Stilz P, Rasmussen MH, Koblitz JC. Vertical sonar beam width and scanning behavior of wild belugas (Delphinapterus leucas) in West Greenland. PLoS One 2021; 16:e0257054. [PMID: 34499678 PMCID: PMC8428689 DOI: 10.1371/journal.pone.0257054] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 08/22/2021] [Indexed: 11/18/2022] Open
Abstract
Echolocation signals of wild beluga whales (Delphinapterus leucas) were recorded in 2013 using a vertical, linear 16-hydrophone array at two locations in the pack ice of Baffin Bay, West Greenland. Individual whales were localized for 4:42 minutes of 1:04 hours of recordings. Clicks centered on the recording equipment (i.e. on-axis clicks) were isolated to calculate sonar parameters. We report the first sonar beam estimate of in situ recordings of wild belugas with an average -3 dB asymmetrical vertical beam width of 5.4°, showing a wider ventral beam. This narrow beam width is consistent with estimates from captive belugas; however, our results indicate that beluga sonar beams may not be symmetrical and may differ in wild and captive contexts. The mean apparent source level for on-axis clicks was 212 dB pp re 1 μPa and whales were shown to vertically scan the array from 120 meters distance. Our findings support the hypothesis that highly directional sonar beams and high source levels are an evolutionary adaptation for Arctic odontocetes to reduce unwanted surface echoes from sea ice (i.e., acoustic clutter) and effectively navigate through leads in the pack ice (e.g., find breathing holes). These results provide the first baseline beluga sonar metrics from free-ranging animals using a hydrophone array and are important for acoustic programs throughout the Arctic, particularly for acoustic classification between belugas and narwhals (Monodon monoceros).
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Affiliation(s)
- Marie J Zahn
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, United States of America
| | - Kristin L Laidre
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, United States of America.,Polar Science Center, Applied Physics Laboratory, University of Washington, Seattle, WA, United States of America
| | - Peter Stilz
- Animal Physiology, Institute for Neurobiology, University of Tübingen, Tübingen, Germany
| | | | - Jens C Koblitz
- Max Planck Institute of Animal Behavior, Konstanz, Germany.,Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany.,Department of Biology, University of Konstanz, Konstanz, Germany
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19
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Malinka CE, Rojano-Doñate L, Madsen PT. Directional biosonar beams allow echolocating harbour porpoises to actively discriminate and intercept closely spaced targets. J Exp Biol 2021; 224:271830. [PMID: 34387665 DOI: 10.1242/jeb.242779] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/28/2021] [Indexed: 10/20/2022]
Abstract
Echolocating toothed whales face the problem that high sound speeds in water mean that echoes from closely spaced targets will arrive at time delays within their reported auditory integration time of some 264 µs. Here, we test the hypothesis that echolocating harbour porpoises cannot resolve and discriminate targets within a clutter interference zone given by their integration time. To do this, we trained two harbour porpoises (Phocoena phocoena) to actively approach and choose between two spherical targets at four varying inter-target distances (13.5, 27, 56 and 108 cm) in a two-alternative forced-choice task. The free-swimming, blindfolded porpoises were tagged with a sound and movement tag (DTAG4) to record their echoic scene and acoustic outputs. The known ranges between targets and the porpoise, combined with the sound levels received on target-mounted hydrophones revealed how the porpoises controlled their acoustic gaze. When targets were close together, the discrimination task was more difficult because of smaller echo time delays and lower echo level ratios between the targets. Under these conditions, buzzes were longer and started from farther away, source levels were reduced at short ranges, and the porpoises clicked faster, scanned across the targets more, and delayed making their discrimination decision until closer to the target. We conclude that harbour porpoises can resolve and discriminate closely spaced targets, suggesting a clutter rejection zone much shorter than their auditory integration time, and that such clutter rejection is greatly aided by spatial filtering with their directional biosonar beam.
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Affiliation(s)
- Chloe E Malinka
- Zoophysiology, Department of Biology, Aarhus University, Aarhus 8000, Denmark
| | - Laia Rojano-Doñate
- Zoophysiology, Department of Biology, Aarhus University, Aarhus 8000, Denmark
| | - Peter T Madsen
- Zoophysiology, Department of Biology, Aarhus University, Aarhus 8000, Denmark
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20
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Hamilton RA, Starkhammar J, Gazda SK, Connor RC. Separating overlapping echolocation: An updated method for estimating the number of echolocating animals in high background noise levels. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 150:709. [PMID: 34470329 DOI: 10.1121/10.0005756] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
Much can be learned by investigating the click trains of odontocetes, including estimating the number of vocalizing animals and comparing the acoustic behavior of different individuals. Analyzing such information gathered from groups of echolocating animals in a natural environment is complicated by two main factors: overlapping echolocation produced by multiple animals at the same time, and varying levels of background noise. Starkhammar et al. [(2011a). Biol. Lett. 7(6), 836-839] described an algorithm that measures and compares the frequency spectra of individual clicks to identify groups of clicks produced by different individuals. This study presents an update to this click group separation algorithm that improves performance by comparing multiple click characteristics. There is a focus on reducing error when high background noise levels cause false click detection and recordings are of a limited frequency bandwidth, making the method applicable to a wide range of existing datasets. This method was successfully tested on recordings of free-swimming foraging dolphins with both low and high natural background noise levels. The algorithm can be adjusted via user-set parameters for application to recordings with varying sampling parameters and to species of varying click characteristics, allowing for estimates of the number of echolocating animals in free-swimming groups.
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Affiliation(s)
- Rebecca A Hamilton
- Biology Department, University of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02747, USA
| | | | - Stefanie K Gazda
- Department of Biology, University of Florida, Gainesville, Florida 32611, USA
| | - Richard C Connor
- Biology Department, University of Massachusetts Dartmouth, North Dartmouth, Massachusetts 02747, USA
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21
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Springer MS, Guerrero-Juarez CF, Huelsmann M, Collin MA, Danil K, McGowen MR, Oh JW, Ramos R, Hiller M, Plikus MV, Gatesy J. Genomic and anatomical comparisons of skin support independent adaptation to life in water by cetaceans and hippos. Curr Biol 2021; 31:2124-2139.e3. [PMID: 33798433 PMCID: PMC8154672 DOI: 10.1016/j.cub.2021.02.057] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 01/21/2021] [Accepted: 02/25/2021] [Indexed: 12/17/2022]
Abstract
The macroevolutionary transition from terra firma to obligatory inhabitance of the marine hydrosphere has occurred twice in the history of Mammalia: Cetacea and Sirenia. In the case of Cetacea (whales, dolphins, and porpoises), molecular phylogenies provide unambiguous evidence that fully aquatic cetaceans and semiaquatic hippopotamids (hippos) are each other's closest living relatives. Ancestral reconstructions suggest that some adaptations to the aquatic realm evolved in the common ancestor of Cetancodonta (Cetacea + Hippopotamidae). An alternative hypothesis is that these adaptations evolved independently in cetaceans and hippos. Here, we focus on the integumentary system and evaluate these hypotheses by integrating new histological data for cetaceans and hippos, the first genome-scale data for pygmy hippopotamus, and comprehensive genomic screens and molecular evolutionary analyses for protein-coding genes that have been inactivated in hippos and cetaceans. We identified eight skin-related genes that are inactivated in both cetaceans and hippos, including genes that are related to sebaceous glands, hair follicles, and epidermal differentiation. However, none of these genes exhibit inactivating mutations that are shared by cetaceans and hippos. Mean dates for the inactivation of skin genes in these two clades serve as proxies for phenotypic changes and suggest that hair reduction/loss, the loss of sebaceous glands, and changes to the keratinization program occurred ∼16 Ma earlier in cetaceans (∼46.5 Ma) than in hippos (∼30.5 Ma). These results, together with histological differences in the integument and prior analyses of oxygen isotopes from stem hippopotamids ("anthracotheres"), support the hypothesis that aquatic skin adaptations evolved independently in hippos and cetaceans.
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Affiliation(s)
- Mark S Springer
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, CA 92521, USA.
| | - Christian F Guerrero-Juarez
- Department of Mathematics, University of California, Irvine, Irvine, CA 92697, USA; NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA 92697, USA; Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA
| | - Matthias Huelsmann
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany; Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany; Center for Systems Biology Dresden, 01307 Dresden, Germany
| | - Matthew A Collin
- Department of Evolution, Ecology, and Organismal Biology, University of California, Riverside, Riverside, CA 92521, USA; Department of Botany & Plant Sciences, University of California, Riverside, Riverside, CA 92521, USA
| | - Kerri Danil
- Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, La Jolla, CA 92037, USA
| | - Michael R McGowen
- Department of Vertebrate Zoology, Smithsonian Museum of Natural History, 10th & Constitution Avenue NW, Washington, DC 20560, USA
| | - Ji Won Oh
- Department of Anatomy, School of Medicine, Kyungpook National University, Daegu, Korea; Biomedical Research Institute, Kyungpook National University Hospital, Daegu, Korea; Hair Transplantation Center, Kyungpook National University Hospital, Daegu, Korea
| | - Raul Ramos
- NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA 92697, USA; Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA
| | - Michael Hiller
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany; Max Planck Institute for the Physics of Complex Systems, 01187 Dresden, Germany; Center for Systems Biology Dresden, 01307 Dresden, Germany; LOEWE Centre for Translational Biodiversity Genomics, 60325 Frankfurt, Germany; Senckenberg Research Institute, 60325 Frankfurt, Germany; Faculty of Biosciences, Goethe-University, 60438 Frankfurt, Germany.
| | - Maksim V Plikus
- NSF-Simons Center for Multiscale Cell Fate Research, University of California, Irvine, Irvine, CA 92697, USA; Department of Developmental and Cell Biology, University of California, Irvine, Irvine, CA 92697, USA; Sue and Bill Gross Stem Cell Research Center, University of California, Irvine, Irvine, CA 92697, USA.
| | - John Gatesy
- Division of Vertebrate Zoology and Sackler Institute for Comparative Genomics, American Museum of Natural History, New York, NY 10024, USA.
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22
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Jakobsen L, Christensen-Dalsgaard J, Juhl PM, Elemans CPH. How Loud Can you go? Physical and Physiological Constraints to Producing High Sound Pressures in Animal Vocalizations. Front Ecol Evol 2021. [DOI: 10.3389/fevo.2021.657254] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Sound is vital for communication and navigation across the animal kingdom and sound communication is unrivaled in accuracy and information richness over long distances both in air and water. The source level (SL) of the sound is a key factor in determining the range at which animals can communicate and the range at which echolocators can operate their biosonar. Here we compile, standardize and compare measurements of the loudest animals both in air and water. In air we find a remarkable similarity in the highest SLs produced across the different taxa. Within all taxa we find species that produce sound above 100 dBpeak re 20 μPa at 1 m, and a few bird and mammal species have SLs as high as 125 dBpeak re 20 μPa at 1 m. We next used pulsating sphere and piston models to estimate the maximum sound pressures generated in the radiated sound field. These data suggest that the loudest species within all taxa converge upon maximum pressures of 140–150 dBpeak re 20 μPa in air. In water, the toothed whales produce by far the loudest SLs up to 240 dBpeak re 1 μPa at 1 m. We discuss possible physical limitations to the production, radiation and propagation of high sound pressures. Furthermore, we discuss physiological limitations to the wide variety of sound generating mechanisms that have evolved in air and water of which many are still not well-understood or even unknown. We propose that in air, non-linear sound propagation forms a limit to producing louder sounds. While non-linear sound propagation may play a role in water as well, both sperm whale and pistol shrimp reach another physical limit of sound production, the cavitation limit in water. Taken together, our data suggests that both in air and water, animals evolved that produce sound so loud that they are pushing against physical rather than physiological limits of sound production, radiation and propagation.
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23
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Frainer G, Huggenberger S, Moreno IB, Plön S, Galatius A. Head adaptation for sound production and feeding strategy in dolphins (Odontoceti: Delphinida). J Anat 2021; 238:1070-1081. [PMID: 33319356 PMCID: PMC8053589 DOI: 10.1111/joa.13364] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 10/29/2020] [Accepted: 11/02/2020] [Indexed: 01/01/2023] Open
Abstract
Head morphology in toothed whales evolved under selective pressures on feeding strategy and sound production. The postnatal development of the skull (n = 207) and mandible (n = 219) of six Delphinida species which differ in feeding strategy but exhibit similar sound emission patterns, including two narrow-band high-frequency species, were investigated through 3D morphometrics. Morphological changes throughout ontogeny were demonstrated based on the main source of variation (i.e., prediction lines) and the common allometric component. Multivariate trajectory analysis with pairwise comparisons between all species was performed to evaluate specific differences on the postnatal development of skulls and mandibles. Changes in the rostrum formation contributed to the variation (skull: 49%; mandible: 90%) of the entire data set and might not only reflect the feeding strategy adopted by each lineage but also represents an adaptation for sound production and reception. As an important structure for directionality of sound emissions, this may increase directionality in raptorial feeders. Phylogenetic generalized least squares analyses indicated that shape of the anterior portion of the skull is strongly dependent on phylogeny and might not only reflect feeding mode, but also morphological adaptations for sound production, particularly in raptorial species. Thus, postnatal development seems to represent a crucial stage for biosonar maturation in some raptorial species such as Pontoporia blainvillei and Sousa plumbea. The ontogeny of their main tool for navigation and hunting might reflect their natural history peculiarities and thus potentially define their main vulnerabilities to anthropogenic changes in the environment.
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Affiliation(s)
- Guilherme Frainer
- Programa de Pós-Graduação em Biologia Animal, Departamento de Zoologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
| | | | - Ignacio B Moreno
- Programa de Pós-Graduação em Biologia Animal, Departamento de Zoologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.,Centro de Estudos Costeiros, Limnológicos e Marinhos (CECLIMAR/CLN/UFRGS), Universidade Federal do Rio Grande do Sul, Imbé, Brazil
| | - Stephanie Plön
- Bayworld Centre for Research and Education (BCRE), Port Elizabeth, South Africa
| | - Anders Galatius
- Marine Mammal Research, Department of Bioscience, Aarhus University, Roskilde, Denmark
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von Benda-Beckmann AM, Isojunno S, Zandvliet M, Ainslie MA, Wensveen PJ, Tyack PL, Kvadsheim PH, Lam FPA, Miller PJO. Modeling potential masking of echolocating sperm whales exposed to continuous 1-2 kHz naval sonar. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 149:2908. [PMID: 33940877 DOI: 10.1121/10.0004769] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 04/02/2021] [Indexed: 06/12/2023]
Abstract
Modern active sonar systems can (almost) continuously transmit and receive sound, which can lead to more masking of important sounds for marine mammals than conventional pulsed sonar systems transmitting at a much lower duty cycle. This study investigated the potential of 1-2 kHz active sonar to mask echolocation-based foraging of sperm whales by modeling their echolocation detection process. Continuous masking for an echolocating sperm whale facing a sonar was predicted for sonar sound pressure levels of 160 dB re 1 μPa2, with intermittent masking at levels of 120 dB re 1 μPa2, but model predictions strongly depended on the animal orientation, harmonic content of the sonar, click source level, and target strength of the prey. The masking model predicted lower masking potential of buzz clicks compared to regular clicks, even though the energy source level is much lower. For buzz clicks, the lower source level is compensated for by the reduced two-way propagation loss to nearby prey during buzzes. These results help to predict what types of behavioral changes could indicate masking in the wild. Several key knowledge gaps related to masking potential of sonar in echolocating odontocetes were identified that require further investigation to assess the significance of masking.
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Affiliation(s)
- A M von Benda-Beckmann
- Acoustics and Sonar, Netherlands Organization for Applied Scientific Research (TNO), P.O. Box 96864, The Hague 2509 JG, The Netherlands
| | - S Isojunno
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 8LB, United Kingdom
| | - M Zandvliet
- Acoustics and Sonar, Netherlands Organization for Applied Scientific Research (TNO), P.O. Box 96864, The Hague 2509 JG, The Netherlands
| | - M A Ainslie
- JASCO Applied Sciences (Deutschland) GmbH, Eschborn, Germany
| | - P J Wensveen
- Faculty of Life and Environmental Sciences, University of Iceland, Askja, Sturlugata 7, 102 Reykjavik, Iceland
| | - P L Tyack
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 8LB, United Kingdom
| | - P H Kvadsheim
- Sensor and Surveillance Systems, Norwegian Defense Research Establishment (FFI), NO-3191 Horten, Norway
| | - F P A Lam
- Acoustics and Sonar, Netherlands Organization for Applied Scientific Research (TNO), P.O. Box 96864, The Hague 2509 JG, The Netherlands
| | - P J O Miller
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife KY16 8LB, United Kingdom
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25
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Pedersen MB, Tønnesen P, Malinka CE, Ladegaard M, Johnson M, Aguilar de Soto N, Madsen PT. Echolocation click parameters of short-finned pilot whales (Globicephala macrorhynchus) in the wild. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 149:1923. [PMID: 33765819 DOI: 10.1121/10.0003762] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 02/23/2021] [Indexed: 06/12/2023]
Abstract
Short-finned pilot whales (Globicephala macrorhynchus) are large, deep-diving predators with diverse foraging strategies, but little is known about their echolocation. To quantify the source properties of short-finned pilot whale clicks, we made 15 deployments off the coast of Tenerife of a deep-water hydrophone array consisting of seven autonomous time-synced hydrophone recorders (SoundTraps), enabling acoustic localization and quantification of click source parameters. Of 8185 recorded pilot whale clicks, 47 were classified as being recorded on-axis, with a mean peak-to-peak source level (SL) of 181 ± 7 dB re 1 μPa, a centroid frequency of 40 ± 4 kHz, and a duration of 57 ± 23 μs. A fit to a piston model yielded an estimated half-power (-3 dB) beam width of 13.7° [95% confidence interval (CI) 13.2°-14.5°] and a mean directivity index (DI) of 22.6 dB (95% CI 22.5-22.9 dB). These measured SLs and DIs are surprisingly low for a deep-diving toothed whale, suggesting we sampled the short-finned pilot whales in a context with little need for operating a long-range biosonar. The substantial spectral overlap with beaked whale clicks emitted in similar deep-water habitats implies that pilot whale clicks may constitute a common source of false detections in beaked whale passive acoustic monitoring efforts.
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Affiliation(s)
- M B Pedersen
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - P Tønnesen
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - C E Malinka
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - M Ladegaard
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - M Johnson
- Aarhus Institute of Advanced Studies, Aarhus University, 8000 Aarhus C, Denmark
| | - N Aguilar de Soto
- Biodiversidad, Ecología Marina y Conservación (BIOECOMAC), University of La Laguna, 38206 La Laguna, Tenerife, Canary Islands, Spain
| | - P T Madsen
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
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26
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Alcázar-Treviño J, Johnson M, Arranz P, Warren VE, Pérez-González CJ, Marques T, Madsen PT, Aguilar de Soto N. Deep-diving beaked whales dive together but forage apart. Proc Biol Sci 2021; 288:20201905. [PMID: 33402065 DOI: 10.1098/rspb.2020.1905] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Echolocating animals that forage in social groups can potentially benefit from eavesdropping on other group members, cooperative foraging or social defence, but may also face problems of acoustic interference and intra-group competition for prey. Here, we investigate these potential trade-offs of sociality for extreme deep-diving Blainville's and Cuvier's beaked whales. These species perform highly synchronous group dives as a presumed predator-avoidance behaviour, but the benefits and costs of this on foraging have not been investigated. We show that group members could hear their companions for a median of at least 91% of the vocal foraging phase of their dives. This enables whales to coordinate their mean travel direction despite differing individual headings as they pursue prey on a minute-by-minute basis. While beaked whales coordinate their echolocation-based foraging periods tightly, individual click and buzz rates are both independent of the number of whales in the group. Thus, their foraging performance is not affected by intra-group competition or interference from group members, and they do not seem to capitalize directly on eavesdropping on the echoes produced by the echolocation clicks of their companions. We conclude that the close diving and vocal synchronization of beaked whale groups that quantitatively reduces predation risk has little impact on foraging performance.
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Affiliation(s)
- Jesús Alcázar-Treviño
- BIOECOMAC, Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna (ULL), Avenida Astrofísico F. Sánchez, s/n. 38206, San Cristóbal de La Laguna (Tenerife), Spain
| | - Mark Johnson
- Aarhus Institute of Advanced Studies, Aarhus University, Høegh-Guldbergs Gade 6B, 8000, Aarhus C, Denmark
| | - Patricia Arranz
- BIOECOMAC, Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna (ULL), Avenida Astrofísico F. Sánchez, s/n. 38206, San Cristóbal de La Laguna (Tenerife), Spain.,Centre for Research into Ecological and Environmental Modelling, University of St Andrews, Fife, KY16 8LB, UK
| | - Victoria E Warren
- Institute of Marine Science, Leigh Marine Laboratory, University of Auckland, 160 Goat Island Road, Leigh 0985, New Zealand
| | - Carlos J Pérez-González
- Departamento de Matemáticas, Estadística e Investigación Operativa, Universidad de La Laguna (ULL), Avenida Astrofísico F. Sánchez, s/n. 38206, San Cristóbal de La Laguna (Tenerife), Spain
| | - Tiago Marques
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, Fife, KY16 8LB, UK.,Departamento de Biologia Animal, Centro de Estatística e Aplicações, Faculdade de Ciências, Universidade de Lisboa, Bloco C6 - Piso 4, Campo Grande, 1749-016 Lisboa, Portugal
| | - Peter T Madsen
- Zoophysiology, Department of Biology, Aarhus University, C.F. Moellers Allé 3, 8000, Aarhus C, Denmark
| | - Natacha Aguilar de Soto
- BIOECOMAC, Departamento de Biología Animal, Edafología y Geología, Universidad de La Laguna (ULL), Avenida Astrofísico F. Sánchez, s/n. 38206, San Cristóbal de La Laguna (Tenerife), Spain
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27
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Beedholm K, Malinka C, Ladegaard M, Madsen PT. Do echolocating toothed whales direct their acoustic gaze on- or off-target in a static detection task? THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 149:581. [PMID: 33514151 DOI: 10.1121/10.0003357] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 12/28/2020] [Indexed: 06/12/2023]
Abstract
Echolocating mammals produce directional sound beams with high source levels to improve echo-to-noise ratios and reduce clutter. Recent studies have suggested that the differential spectral gradients of such narrow beams are exploited to facilitate target localization by pointing the beam slightly off targets to maximize the precision of angular position estimates [maximizing bearing Fisher information (FI)]. Here, we test the hypothesis that echolocating toothed whales focus their acoustic gaze askew during target detection to maximize spectral cues by investigating the acoustic gaze direction of two trained delphinids (Tursiops truncatus and Pseudorca crassidens) echolocating to detect an aluminum cylinder behind a hydrophone array in a go/no-go paradigm. The animals rarely placed their beam axis directly on the target, nor within the narrow range around the off-axis angle that maximizes FI. However, the target was, for each trial, ensonified within the swath of the half-power beam width, and hence we conclude that the animals solved the detection task using a strategy that seeks to render high echo-to-noise ratios rather than maximizing bearing FI. We posit that biosonar beam adjustment and acoustic gaze strategies are likely task-dependent and that maximizing bearing FI by pointing off-axis does not improve target detection performance.
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Affiliation(s)
- Kristian Beedholm
- Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - Chloe Malinka
- Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - Michael Ladegaard
- Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
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28
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Laeta M, Ruenes GF, Siciliano S, Oliveira JA, Galatius A. Variation in cranial asymmetry among the Delphinoidea. Biol J Linn Soc Lond 2020. [DOI: 10.1093/biolinnean/blaa161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Abstract
The remarkable directional cranial asymmetry of odontocete skulls has been proposed to be related to sound production. We investigated the variation in quality and quantity of cranial asymmetry in the superfamily Delphinoidea using geometric morphometrics and then investigated the relationship between asymmetry and aspects of sound production. In the average asymmetric shape, the dorsal aspect of the skull outline and interparietal suture crest were displaced to the right, while the nasal septum, nasal bones and right premaxilla were displaced to the left. The nasal bone, premaxilla and maxilla were all larger on the right side. Three delphinoid families presented similar expressions of asymmetry; however, the magnitude of the asymmetry varied. The Monodontidae showed the greatest magnitude of asymmetry, whereas the Phocoenidae were much less asymmetric. The most speciose family, the Delphinidae, presented a wide spectrum of asymmetry, with globicephalines and lissodelphinines among the most and least asymmetric species, respectively. Generalized linear models explaining the magnitude of asymmetry with characteristics of echolocation clicks, habitat use and size revealed associations with source level, dive depth and centroid size. This supports a relationship between asymmetry and sound production, with more asymmetric species emitting louder sounds. For example, louder clicks would be beneficial for prey detection at longer ranges in deeper waters.
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Affiliation(s)
- Maíra Laeta
- Programa de Pós-graduação em Biodiversidade e Biologia Evolutiva, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Setor de Mastozoologia, Departamento de Vertebrados, Museu Nacional/Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
- Grupo de Estudos de Mamíferos Marinhos da Região dos Lagos, Praia Seca, Araruama, RJ, Brazil
| | - Greicy F Ruenes
- Programa de Pós-graduação em Ecologia e Recursos Naturais, Universidade Estadual do Norte Fluminense “Darcy Ribeiro”, Campos dos Goytacazes, RJ, Brazil
- Laboratório de Ecologia de Mamíferos, Universidade do Vale do Rio dos Sinos, São Leopoldo, RS, Brazil
| | - Salvatore Siciliano
- Laboratório de Biodiversidade, Instituto Oswaldo Cruz/Fiocruz, Rio de Janeiro, Rio de Janeiro, Brazil
- Grupo de Estudos de Mamíferos Marinhos da Região dos Lagos, Praia Seca, Araruama, RJ, Brazil
| | - João A Oliveira
- Setor de Mastozoologia, Departamento de Vertebrados, Museu Nacional/Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Anders Galatius
- Marine Mammal Research, Department of Bioscience, Aarhus University, Roskilde, Denmark
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29
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Finneran AE, Mulsow J, Finneran JJ. Detection of simulated patterned echo packets by bottlenose dolphins (Tursiops truncatus). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2020; 148:1007. [PMID: 32872998 DOI: 10.1121/10.0001777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 08/03/2020] [Indexed: 06/11/2023]
Abstract
Dolphins performing long-range biosonar tasks sometimes use "packets" of clicks, where inter-click-intervals within each packet are less than the two-way acoustic travel time from dolphin to target. The multi-echo nature of packets results in lower detection thresholds than single echoes; however, other potential benefits of packet use remain unexplored. The present study investigated whether structured temporal patterns observed in click packets impart some advantage in detecting echo-like signals embedded in noise. Two bottlenose dolphins were trained to passively listen and detect simulated packets of echoes in background noise consisting of either steady-state broadband Gaussian noise, or Gaussian noise containing randomly presented impulses similar to dolphin clicks. Four different inter-stimulus-interval (ISI) patterns (constant, random, increasing, or decreasing ISI within each packet) were tested. It was hypothesized that decreasing ISIs-found naturally in dolphin packets-would result in the lowest thresholds, while random, unlearnable patterns would result in the highest. However, no biologically significant differences in threshold were found among the four ISI patterns for either noise condition. Thus, the bottlenose dolphin's stereotypical pattern of decreasing ISI during active echolocation did not appear to provide an advantage in packet detection in this passive listening task.
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Affiliation(s)
- Ann E Finneran
- UCLA Department of Ecology and Evolutionary Biology, 612 Charles E. Young Drive South, Box 957246, Los Angeles, California 90095-7246, USA
| | - Jason Mulsow
- National Marine Mammal Foundation, 2240 Shelter Island Drive #200, San Diego, California 92106, USA
| | - James J Finneran
- U.S. Navy Marine Mammal Program, Naval Information Warfare Center Pacific Code 56710, 53560 Hull Street, San Diego, California 92152, USA
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Coombs EJ, Clavel J, Park T, Churchill M, Goswami A. Wonky whales: the evolution of cranial asymmetry in cetaceans. BMC Biol 2020; 18:86. [PMID: 32646447 PMCID: PMC7350770 DOI: 10.1186/s12915-020-00805-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/01/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Unlike most mammals, toothed whale (Odontoceti) skulls lack symmetry in the nasal and facial (nasofacial) region. This asymmetry is hypothesised to relate to echolocation, which may have evolved in the earliest diverging odontocetes. Early cetaceans (whales, dolphins, and porpoises) such as archaeocetes, namely the protocetids and basilosaurids, have asymmetric rostra, but it is unclear when nasofacial asymmetry evolved during the transition from archaeocetes to modern whales. We used three-dimensional geometric morphometrics and phylogenetic comparative methods to reconstruct the evolution of asymmetry in the skulls of 162 living and extinct cetaceans over 50 million years. RESULTS In archaeocetes, we found asymmetry is prevalent in the rostrum and also in the squamosal, jugal, and orbit, possibly reflecting preservational deformation. Asymmetry in odontocetes is predominant in the nasofacial region. Mysticetes (baleen whales) show symmetry similar to terrestrial artiodactyls such as bovines. The first significant shift in asymmetry occurred in the stem odontocete family Xenorophidae during the Early Oligocene. Further increases in asymmetry occur in the physeteroids in the Late Oligocene, Squalodelphinidae and Platanistidae in the Late Oligocene/Early Miocene, and in the Monodontidae in the Late Miocene/Early Pliocene. Additional episodes of rapid change in odontocete skull asymmetry were found in the Mid-Late Oligocene, a period of rapid evolution and diversification. No high-probability increases or jumps in asymmetry were found in mysticetes or archaeocetes. Unexpectedly, no increases in asymmetry were recovered within the highly asymmetric ziphiids, which may result from the extreme, asymmetric shape of premaxillary crests in these taxa not being captured by landmarks alone. CONCLUSIONS Early ancestors of living whales had little cranial asymmetry and likely were not able to echolocate. Archaeocetes display high levels of asymmetry in the rostrum, potentially related to directional hearing, which is lost in early neocetes-the taxon including the most recent common ancestor of living cetaceans. Nasofacial asymmetry becomes a significant feature of Odontoceti skulls in the Early Oligocene, reaching its highest levels in extant taxa. Separate evolutionary regimes are reconstructed for odontocetes living in acoustically complex environments, suggesting that these niches impose strong selective pressure on echolocation ability and thus increased cranial asymmetry.
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Affiliation(s)
- Ellen J Coombs
- Genetics, Evolution, and Environment Department, University College London, Gower Street, London, WC1E 6BT, UK.
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK.
| | - Julien Clavel
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR 5023 LEHNA, F-69622, Villeurbanne, France
| | - Travis Park
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
- Department of Earth Sciences, University of Oxford, Oxford, OX1 3AN, UK
| | - Morgan Churchill
- Department of Biology, University of Wisconsin-Oshkosh, Oshkosh, WI, 54901, USA
| | - Anjali Goswami
- Genetics, Evolution, and Environment Department, University College London, Gower Street, London, WC1E 6BT, UK
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
- Department of Earth Sciences, University College London, Gower Street, London, WC1E 6BT, UK
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31
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Macaulay JDJ, Malinka CE, Gillespie D, Madsen PT. High resolution three-dimensional beam radiation pattern of harbour porpoise clicks with implications for passive acoustic monitoring. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2020; 147:4175. [PMID: 32611133 DOI: 10.1121/10.0001376] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Accepted: 05/13/2020] [Indexed: 06/11/2023]
Abstract
The source properties and radiation patterns of animal vocalisations define, along with propagation and noise conditions, the active space in which these vocalisations can be detected by conspecifics, predators, prey, and by passive acoustic monitoring (PAM). This study reports the 4π (360° horizontal and vertical) beam profile of a free-swimming, trained harbour porpoise measured using a 27-element hydrophone array. The forward echolocation beam is highly directional, as predicted by a piston model, and is consistent with previous measurements. However, at off-axis angles greater than ±30°, the beam attenuates more rapidly than the piston model and no side lobes are present. A diffuse back beam is also present with levels about -30 dB relative to the source level. In PAM, up to 50% of detections can be from portions of the beam profile with distorted click spectra, although this drops substantially for higher detection thresholds. Simulations of the probability of acoustically detecting a harbour porpoise show that a traditional piston model can underestimate the probability of detection compared to the actual three-dimensional radiation pattern documented here. This highlights the importance of empirical 4π measurements of beam profiles of toothed whales, both to improve understanding of toothed whale biology and to inform PAM.
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Affiliation(s)
- Jamie D J Macaulay
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of Saint Andrews, East Sands, Saint Andrews, Fife, KY16 9LB, United Kingdom
| | - Chloe E Malinka
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark
| | - Douglas Gillespie
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of Saint Andrews, East Sands, Saint Andrews, Fife, KY16 9LB, United Kingdom
| | - Peter T Madsen
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus C, Denmark
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32
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McGowen MR, Tsagkogeorga G, Williamson J, Morin PA, Rossiter ASJ. Positive Selection and Inactivation in the Vision and Hearing Genes of Cetaceans. Mol Biol Evol 2020; 37:2069-2083. [DOI: 10.1093/molbev/msaa070] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Abstract
The transition to an aquatic lifestyle in cetaceans (whales and dolphins) resulted in a radical transformation in their sensory systems. Toothed whales acquired specialized high-frequency hearing tied to the evolution of echolocation, whereas baleen whales evolved low-frequency hearing. More generally, all cetaceans show adaptations for hearing and seeing underwater. To determine the extent to which these phenotypic changes have been driven by molecular adaptation, we performed large-scale targeted sequence capture of 179 sensory genes across the Cetacea, incorporating up to 54 cetacean species from all major clades as well as their closest relatives, the hippopotamuses. We screened for positive selection in 167 loci related to vision and hearing and found that the diversification of cetaceans has been accompanied by pervasive molecular adaptations in both sets of genes, including several loci implicated in nonsyndromic hearing loss. Despite these findings, however, we found no direct evidence of positive selection at the base of odontocetes coinciding with the origin of echolocation, as found in studies examining fewer taxa. By using contingency tables incorporating taxon- and gene-based controls, we show that, although numbers of positively selected hearing and nonsyndromic hearing loss genes are disproportionately high in cetaceans, counts of vision genes do not differ significantly from expected values. Alongside these adaptive changes, we find increased evidence of pseudogenization of genes involved in cone-mediated vision in mysticetes and deep-diving odontocetes.
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Affiliation(s)
- Michael R McGowen
- School of Biological and Chemical Sciences, Queen Mary, University of London, London, United Kingdom
- Department of Vertebrate Zoology, Smithsonian National Museum of Natural History, Washington, DC
| | - Georgia Tsagkogeorga
- School of Biological and Chemical Sciences, Queen Mary, University of London, London, United Kingdom
| | - Joseph Williamson
- School of Biological and Chemical Sciences, Queen Mary, University of London, London, United Kingdom
| | - Phillip A Morin
- Southwest Fisheries Science Center, National Marine Fisheries Service, NOAA, La Jolla, CA
| | - and Stephen J Rossiter
- School of Biological and Chemical Sciences, Queen Mary, University of London, London, United Kingdom
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33
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Goldbogen JA, Cade DE, Wisniewska DM, Potvin J, Segre PS, Savoca MS, Hazen EL, Czapanskiy MF, Kahane-Rapport SR, DeRuiter SL, Gero S, Tønnesen P, Gough WT, Hanson MB, Holt MM, Jensen FH, Simon M, Stimpert AK, Arranz P, Johnston DW, Nowacek DP, Parks SE, Visser F, Friedlaender AS, Tyack PL, Madsen PT, Pyenson ND. Why whales are big but not bigger: Physiological drivers and ecological limits in the age of ocean giants. Science 2020; 366:1367-1372. [PMID: 31831666 DOI: 10.1126/science.aax9044] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 10/31/2019] [Indexed: 12/27/2022]
Abstract
The largest animals are marine filter feeders, but the underlying mechanism of their large size remains unexplained. We measured feeding performance and prey quality to demonstrate how whale gigantism is driven by the interplay of prey abundance and harvesting mechanisms that increase prey capture rates and energy intake. The foraging efficiency of toothed whales that feed on single prey is constrained by the abundance of large prey, whereas filter-feeding baleen whales seasonally exploit vast swarms of small prey at high efficiencies. Given temporally and spatially aggregated prey, filter feeding provides an evolutionary pathway to extremes in body size that are not available to lineages that must feed on one prey at a time. Maximum size in filter feeders is likely constrained by prey availability across space and time.
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Affiliation(s)
- J A Goldbogen
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA.
| | - D E Cade
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA
| | - D M Wisniewska
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA
| | - J Potvin
- Department of Physics, Saint Louis University, St. Louis, MO, USA
| | - P S Segre
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA
| | - M S Savoca
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA
| | - E L Hazen
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA.,Environmental Research Division, National Oceanic and Atmospheric Administration, Southwest Fisheries Science Center, Monterey, CA, USA.,Institute of Marine Sciences, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - M F Czapanskiy
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA
| | - S R Kahane-Rapport
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA
| | - S L DeRuiter
- Mathematics and Statistics Department, Calvin University, Grand Rapids, MI, USA
| | - S Gero
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark
| | - P Tønnesen
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark
| | - W T Gough
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, CA, USA
| | - M B Hanson
- Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, USA
| | - M M Holt
- Conservation Biology Division, Northwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Seattle, WA, USA
| | - F H Jensen
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA, USA
| | - M Simon
- Greenland Climate Research Centre, Greenland Institute of Natural Resources, Nuuk, Greenland
| | - A K Stimpert
- Moss Landing Marine Laboratories, Moss Landing, CA, USA
| | - P Arranz
- Biodiversity, Marine Ecology and Conservation Group, Department of Animal Biology, University of La Laguna, La Laguna, Spain
| | - D W Johnston
- Nicholas School of the Environment, Duke University Marine Laboratory, Beaufort, NC, USA
| | - D P Nowacek
- Pratt School of Engineering, Duke University, Durham, NC, USA
| | - S E Parks
- Department of Biology, Syracuse University, Syracuse, NY, USA
| | - F Visser
- Department of Freshwater and Marine Ecology, IBED, University of Amsterdam, Amsterdam, Netherlands.,Department of Coastal Systems, NIOZ and Utrecht University, Utrecht, Netherlands.,Kelp Marine Research, Hoorn, Netherlands
| | - A S Friedlaender
- Institute of Marine Sciences, University of California, Santa Cruz, Santa Cruz, CA, USA
| | - P L Tyack
- Sea Mammal Research Unit, School of Biology, Scottish Oceans Institute, University of St Andrews, St Andrews, UK
| | - P T Madsen
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark.,Aarhus Institute of Advanced Studies, Aarhus University, DK-8000 Aarhus C, Denmark
| | - N D Pyenson
- Department of Paleobiology, National Museum of Natural History, Washington, DC, USA.,Department of Paleontology and Geology, Burke Museum of Natural History and Culture, Seattle, WA, USA
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Jensen FH, Keller OA, Tyack PL, Visser F. Dynamic biosonar adjustment strategies in deep-diving Risso's dolphins driven partly by prey evasion. ACTA ACUST UNITED AC 2020; 223:jeb.216283. [PMID: 31822550 DOI: 10.1242/jeb.216283] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 12/02/2019] [Indexed: 11/20/2022]
Abstract
Toothed whales have evolved flexible biosonar systems to find, track and capture prey in diverse habitats. Delphinids, phocoenids and iniids adjust inter-click intervals and source levels gradually while approaching prey. In contrast, deep-diving beaked and sperm whales maintain relatively constant inter-click intervals and apparent output levels during the approach followed by a rapid transition into the foraging buzz, presumably to maintain a long-range acoustic scene in a multi-target environment. However, it remains unknown whether this rapid biosonar adjustment strategy is shared by delphinids foraging in deep waters. To test this, we investigated biosonar adjustments of a deep-diving delphinid, the Risso's dolphin (Grampus griseus). We analyzed inter-click interval and apparent output level adjustments recorded from sound recording tags to quantify in situ sensory adjustment during prey capture attempts. Risso's dolphins did not follow typical (20logR) biosonar adjustment patterns seen in shallow-water species, but instead maintained stable repetition rates and output levels up to the foraging buzz. Our results suggest that maintaining a long-range acoustic scene to exploit complex, multi-target prey layers is a common strategy amongst deep-diving toothed whales. Risso's dolphins transitioned rapidly into the foraging buzz just like beaked whales during most foraging attempts, but employed a more gradual biosonar adjustment in a subset (19%) of prey approaches. These were characterized by higher speeds and minimum specific acceleration, indicating higher prey capture efforts associated with evasive prey. Thus, tracking and capturing evasive prey using biosonar may require a more gradual switch between multi-target echolocation and single-target tracking.
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Affiliation(s)
- Frants H Jensen
- Aarhus Institute of Advanced Studies, Aarhus University, 8000 Aarhus C, Denmark .,Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Onno A Keller
- Department of Coastal Systems, Royal Netherlands Institute for Sea Research and Utrecht University, P.O. Box 59, 1790 AB Den Burg Texel, The Netherlands.,Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1090 GE Amsterdam, The Netherlands.,Department of Animal Ecology, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Peter L Tyack
- Scottish Oceans Institute, School of Biology, University of St Andrews, East Sands, St Andrews KY16 8LB, UK
| | - Fleur Visser
- Department of Coastal Systems, Royal Netherlands Institute for Sea Research and Utrecht University, P.O. Box 59, 1790 AB Den Burg Texel, The Netherlands.,Department of Freshwater and Marine Ecology, Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1090 GE Amsterdam, The Netherlands.,Kelp Marine Research, 1624CJ Hoorn, The Netherlands
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35
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Information limitation and the dynamics of coupled ecological systems. Nat Ecol Evol 2019; 4:82-90. [PMID: 31659309 DOI: 10.1038/s41559-019-1008-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 09/16/2019] [Indexed: 01/09/2023]
Abstract
The dynamics of large ecological systems result from vast numbers of interactions between individual organisms. Here, we develop mathematical theory to show that the rate of such interactions is inherently limited by the ability of organisms to gain information about one another. This phenomenon, which we call 'information limitation', is likely to be widespread in real ecological systems and can dictate both the rates of ecological interactions and long-run dynamics of interacting populations. We show how information limitation leads to sigmoid interaction rate functions that can stabilize antagonistic interactions and destabilize mutualistic ones; as a species or type becomes rare, information on its whereabouts also becomes rare, weakening coupling with consumers, pathogens and mutualists. This can facilitate persistence of consumer-resource systems, alter the course of pathogen infections within a host and enhance the rates of oceanic productivity and carbon export. Our findings may shed light on phenomena in many living systems where information drives interactions.
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36
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Park T, Mennecart B, Costeur L, Grohé C, Cooper N. Convergent evolution in toothed whale cochleae. BMC Evol Biol 2019; 19:195. [PMID: 31651234 PMCID: PMC6813997 DOI: 10.1186/s12862-019-1525-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 10/01/2019] [Indexed: 11/10/2022] Open
Abstract
Background Odontocetes (toothed whales) are the most species-rich marine mammal lineage. The catalyst for their evolutionary success is echolocation - a form of biological sonar that uses high-frequency sound, produced in the forehead and ultimately detected by the cochlea. The ubiquity of echolocation in odontocetes across a wide range of physical and acoustic environments suggests that convergent evolution of cochlear shape is likely to have occurred. To test this, we used SURFACE; a method that fits Ornstein-Uhlenbeck (OU) models with stepwise AIC (Akaike Information Criterion) to identify convergent regimes on the odontocete phylogeny, and then tested whether convergence in these regimes was significantly greater than expected by chance. Results We identified three convergent regimes: (1) True’s (Mesoplodon mirus) and Cuvier’s (Ziphius cavirostris) beaked whales; (2) sperm whales (Physeter macrocephalus) and all other beaked whales sampled; and (3) pygmy (Kogia breviceps) and dwarf (Kogia sima) sperm whales and Dall’s porpoise (Phocoenoides dalli). Interestingly the ‘river dolphins’, a group notorious for their convergent morphologies and riverine ecologies, do not have convergent cochlear shapes. The first two regimes were significantly convergent, with habitat type and dive type significantly correlated with membership of the sperm whale + beaked whale regime. Conclusions The extreme acoustic environment of the deep ocean likely constrains cochlear shape, causing the cochlear morphology of sperm and beaked whales to converge. This study adds support for cochlear morphology being used to predict the ecology of extinct cetaceans.
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Affiliation(s)
- Travis Park
- Department of Life Sciences, Natural History Museum, Cromwell Road, SW7 5BD, London, UK.
| | - Bastien Mennecart
- Naturhistorisches Museum Basel, Augustinergasse 2, 4001, Basel, Switzerland.,Naturhistorisches Museum Wien, Burgring 7, 1010, Vienna, Austria
| | - Loïc Costeur
- Naturhistorisches Museum Basel, Augustinergasse 2, 4001, Basel, Switzerland
| | - Camille Grohé
- Division of Paleontology, American Museum of Natural History, Central Park West at 79th Street, New York, NY, 10024, USA.,Laboratory Paleontology Evolution Paleoecosystems Paleoprimatology (PALEVOPRIM) - UMR 7262, CNRS-INEE/University of Poitiers, 86073, Poitiers Cedex 9, France
| | - Natalie Cooper
- Department of Life Sciences, Natural History Museum, Cromwell Road, SW7 5BD, London, UK
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Frainer G, Moreno IB, Serpa N, Galatius A, Wiedermann D, Huggenberger S. Ontogeny and evolution of the sound-generating structures in the infraorder Delphinida (Odontoceti: Delphinida). Biol J Linn Soc Lond 2019. [DOI: 10.1093/biolinnean/blz118] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AbstractThe ontogeny of the structures involved in sound generation and modulation in dolphins was investigated through a comparison of the soft nasal structures of foetal, perinatal, neonatal and adult specimens of Pontoporiidae, Phocoenidae and Delphinidae. Foetal samples were sectioned at 10 µm in the saggital and coronal planes, and stained for histological examination. Computed tomography and magentic resonance imaging scan series were combined with new data to represent the ontogenetic stages of the three groups. The images were analysed in 3D-Slicer to characterize the general head topography. The origins of the melon and the vestibular air sac were detected between Carnegie stages C16 and F22. The three groups analysed showed distinct formation of the nasal plug and nasal plug muscles, mainly with regard to the loss of fat pathways (or their maintenance in Pontoporiidae) and the development of the nasal plug muscles on both sides (during perinatal development of Phocoenidae) or just on the left side (during postnatal development in Delphinidae). Broadband vocalizing delphinidans might have evolved under heterochronic events acting on the formation of sound-generating structures such as the rostrum and vestibular air sacs, and on the transformation of the branches of the melon, probably leading to a reduced directionality of the sonar beam.
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Affiliation(s)
- Guilherme Frainer
- Programa de Pós-Graduação em Biologia Animal, Departamento de Zoologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Centro de Estudos Costeiros, Limnológicos e Marinhos (CECLIMAR/UFRGS), Campus Litoral Norte, Universidade Federal do Rio Grande do Sul, Imbé, Brazil
- Department II of Anatomy, University of Cologne, Cologne, Germany
| | - Ignacio B Moreno
- Programa de Pós-Graduação em Biologia Animal, Departamento de Zoologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Centro de Estudos Costeiros, Limnológicos e Marinhos (CECLIMAR/UFRGS), Campus Litoral Norte, Universidade Federal do Rio Grande do Sul, Imbé, Brazil
| | - Nathalia Serpa
- Programa de Pós-Graduação em Biologia Animal, Departamento de Zoologia, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil
- Centro de Estudos Costeiros, Limnológicos e Marinhos (CECLIMAR/UFRGS), Campus Litoral Norte, Universidade Federal do Rio Grande do Sul, Imbé, Brazil
| | - Anders Galatius
- Department of Bioscience, Aarhus University, Roskilde, Denmark
| | - Dirk Wiedermann
- Max Planck Institute for Metabolism Research, Cologne, Germany
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38
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Gong Z, Dong L, Caruso F, Lin M, Liu M, Dong J, Li S. Echolocation signals of free-ranging pantropical spotted dolphins (Stenella attenuata) in the South China Sea. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 145:3480. [PMID: 31255156 DOI: 10.1121/1.5111742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Accepted: 05/28/2019] [Indexed: 06/09/2023]
Abstract
Echolocation signals of free-ranging pantropical spotted dolphins (Stenella attenuata) in the western Pacific Ocean have not been studied much. This paper aims to describe the characteristics of echolocation signals of S. attenuata in the northern South China Sea. A six-arm star array with 13 hydrophones was used and a total of 131 on-axis clicks were identified to analyze the acoustic features of the echolocation signals of dolphins. The mean center frequency was 89 ± 13 kHz, with mean peak-to-peak sound source levels of 190 ± 6 dB re: 1 μPa @ 1 m. The mean -3 dB bandwidth and root-mean-square bandwidth were 62 ± 15 kHz and 26 ± 3 kHz, respectively, with mean -10 dB duration of 18 ± 4 μs and root-mean-square duration of 6 ± 2 μs. The results showed that click parameters of S. attenuata in the northern South China Sea are different from those of clicks of the species in Hawaii waters. The differences in click parameters may be due to both behavioral context and/or environmental adaptation of S. attenuata in different habitats.
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Affiliation(s)
- Zining Gong
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, China
| | - Lijun Dong
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, China
| | - Francesco Caruso
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, China
| | - Mingli Lin
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, China
| | - Mingming Liu
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, China
| | - Jianchen Dong
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, China
| | - Songhai Li
- Sanya Key Laboratory of Marine Mammal and Marine Bioacoustics, Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, 572000, China
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Smith AB, Pacini AF, Nachtigall PE, Laule GE, Aragones LV, Magno C, Suarez LJA. Transmission beam pattern and dynamics of a spinner dolphin (Stenella longirostris). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 145:3595. [PMID: 31255135 DOI: 10.1121/1.5111347] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 05/24/2019] [Indexed: 06/09/2023]
Abstract
Toothed whales possess a sophisticated biosonar system by which ultrasonic clicks are projected in a highly directional transmission beam. Beam directivity is an important biosonar characteristic that reduces acoustic clutter and increases the acoustic detection range. This study measured click characteristics and the transmission beam pattern from a small odontocete, the spinner dolphin (Stenella longirostis). A formerly stranded individual was rehabilitated and trained to station underwater in front of a 16-element hydrophone array. On-axis clicks showed a mean duration of 20.1 μs, with mean peak and centroid frequencies of 58 and 64 kHz [standard deviation (s.d.) ±30 and ±12 kHz], respectively. Clicks were projected in an oval, vertically compressed beam, with mean vertical and horizontal beamwidths of 14.5° (s.d. ± 3.9) and 16.3° (s.d. ± 4.6), respectively. Directivity indices ranged from 14.9 to 27.4 dB, with a mean of 21.7 dB, although this likely represents a broader beam than what is normally produced by wild individuals. A click subset with characteristics more similar to those described for wild individuals exhibited a mean directivity index of 23.3 dB. Although one of the broadest transmission beams described for a dolphin, it is similar to other small bodied odontocetes.
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Affiliation(s)
- Adam B Smith
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii at Manoa, Kaneohe, Hawaii 96744, USA
| | - Aude F Pacini
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii at Manoa, Kaneohe, Hawaii 96744, USA
| | - Paul E Nachtigall
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, University of Hawaii at Manoa, Kaneohe, Hawaii 96744, USA
| | - Gail E Laule
- Ocean Adventure, Camayan Wharf, West Ilanin Forest, Subic Bay Freeport Zone, Philippines
| | - Lemnuel V Aragones
- Institute of Environmental Science and Meteorology, University of the Philippines, Diliman, Quezon City, Philippines
| | - Carlo Magno
- Ocean Adventure, Camayan Wharf, West Ilanin Forest, Subic Bay Freeport Zone, Philippines
| | - Leo J A Suarez
- Ocean Adventure, Camayan Wharf, West Ilanin Forest, Subic Bay Freeport Zone, Philippines
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40
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Ladegaard M, Mulsow J, Houser DS, Jensen FH, Johnson M, Madsen PT, Finneran JJ. Dolphin echolocation behaviour during active long-range target approaches. ACTA ACUST UNITED AC 2019; 222:jeb.189217. [PMID: 30478155 DOI: 10.1242/jeb.189217] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 11/22/2018] [Indexed: 11/20/2022]
Abstract
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 than the TWTT. We conclude that the click-echo-click paradigm is not a fixed echolocation strategy in dolphins, and we demonstrate the first use of click packets for free-swimming dolphins when solving an echolocation task.
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Affiliation(s)
- Michael Ladegaard
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
| | - Jason Mulsow
- National Marine Mammal Foundation, 2240 Shelter Island Drive, Suite 200, San Diego, CA 92106, USA
| | - Dorian S Houser
- National Marine Mammal Foundation, 2240 Shelter Island Drive, Suite 200, San Diego, CA 92106, USA
| | | | - Mark Johnson
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark.,Sea Mammal Research Unit, St Andrews KY16 8LB, UK
| | - Peter Teglberg Madsen
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark.,Aarhus Institute of Advanced Studies, Aarhus University, 8000 Aarhus, Denmark
| | - James J Finneran
- United States Navy Marine Mammal Program, Space and Naval Warfare Systems Center Pacific, Code 71510, 53560 Hull Street, San Diego, CA 92152, USA
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