51
|
Zaugg S, van der Schaar M, Houégnigan L, André M. Extraction of pulse repetition intervals from sperm whale click trains for ocean acoustic data mining. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2013; 133:902-911. [PMID: 23363108 DOI: 10.1121/1.4773278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The analysis of acoustic data from the ocean is a valuable tool to study free ranging cetaceans and anthropogenic noise. Due to the typically large volume of acquired data, there is a demand for automated analysis techniques. Many cetaceans produce acoustic pulses (echolocation clicks) with a pulse repetition interval (PRI) remaining nearly constant over several pulses. Analyzing these pulse trains is challenging because they are often interleaved. This article presents an algorithm that estimates a pulse's PRI with respect to neighboring pulses. It includes a deinterleaving step that operates via a spectral dissimilarity metric. The sperm whale (SW) produces trains with PRIs between 0.5 and 2 s. As a validation, the algorithm was used for the PRI-based identification of SW click trains with data from the NEMO-ONDE observatory that contained other pulsed sounds, mainly from ship propellers. Separation of files containing SW clicks with a medium and high signal to noise ratio from files containing other pulsed sounds gave an area under the receiver operating characteristic curve value of 0.96. This study demonstrates that PRI can be used for the automated identification of SW clicks and that deinterleaving via spectral dissimilarity contributes to algorithm performance.
Collapse
Affiliation(s)
- Serge Zaugg
- Laboratori d'Aplicacions Bioacústiques, Universitat Politècnica de Catalunya (UPC, Barcelona Tech), 08800 Vilanova i la Geltrú, Spain
| | | | | | | |
Collapse
|
52
|
Jensen FH, Perez JM, Johnson M, Soto NA, Madsen PT. Calling under pressure: short-finned pilot whales make social calls during deep foraging dives. Proc Biol Sci 2011; 278:3017-25. [PMID: 21345867 PMCID: PMC3158928 DOI: 10.1098/rspb.2010.2604] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Accepted: 02/03/2011] [Indexed: 11/12/2022] Open
Abstract
Toothed whales rely on sound to echolocate prey and communicate with conspecifics, but little is known about how extreme pressure affects pneumatic sound production in deep-diving species with a limited air supply. The short-finned pilot whale (Globicephala macrorhynchus) is a highly social species among the deep-diving toothed whales, in which individuals socialize at the surface but leave their social group in pursuit of prey at depths of up to 1000 m. To investigate if these animals communicate acoustically at depth and test whether hydrostatic pressure affects communication signals, acoustic DTAGs logging sound, depth and orientation were attached to 12 pilot whales. Tagged whales produced tonal calls during deep foraging dives at depths of up to 800 m. Mean call output and duration decreased with depth despite the increased distance to conspecifics at the surface. This shows that the energy content of calls is lower at depths where lungs are collapsed and where the air volume available for sound generation is limited by ambient pressure. Frequency content was unaffected, providing a possible cue for group or species identification of diving whales. Social calls may be important to maintain social ties for foraging animals, but may be impacted adversely by vessel noise.
Collapse
Affiliation(s)
- Frants H Jensen
- Zoophysiology, Department of Biological Sciences, Aarhus University, 8000 Aarhus, Denmark.
| | | | | | | | | |
Collapse
|
53
|
Wahlberg M, Jensen FH, Soto NA, Beedholm K, Bejder L, Oliveira C, Rasmussen M, Simon M, Villadsgaard A, Madsen PT. Source parameters of echolocation clicks from wild bottlenose dolphins (Tursiops aduncus and Tursiops truncatus). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2011; 130:2263-2274. [PMID: 21973382 DOI: 10.1121/1.3624822] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The Indian Ocean and Atlantic bottlenose dolphins (Tursiops aduncus and Tursiops truncatus) are among the best studied echolocating toothed whales. However, almost all echolocation studies on bottlenose dolphins have been made with captive animals, and the echolocation signals of free-ranging animals have not been quantified. Here, biosonar source parameters from wild T. aduncus and T. truncatus were measured with linear three- and four-hydrophone arrays in four geographic locations. The two species had similar source parameters, with source levels of 177-228 dB re 1 μPa peak to peak, click durations of 8-72 μs, centroid frequencies of 33-109 kHz and rms bandwidths between 23 and 54 kHz. T. aduncus clicks had a higher frequency emphasis than T. truncatus. The transmission directionality index was up to 3 dB higher for T. aduncus (29 dB) as compared to T. truncatus (26 dB). The high directionality of T. aduncus does not appear to be only a physical consequence of a higher frequency emphasis in clicks, but may also be caused by differences in the internal properties of the sound production system.
Collapse
Affiliation(s)
- Magnus Wahlberg
- Fjord & Bælt and Marine Research Laboratory, University of Southern Denmark, Margrethes Plads 1, 5300 Kerteminde, Denmark.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
54
|
Baggenstoss PM. Separation of sperm whale click-trains for multipath rejection. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2011; 129:3598-3609. [PMID: 21682385 DOI: 10.1121/1.3578454] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In this paper an algorithm is described for grouping sperm whale clicks received at a single hydrophone into click-trains associated with a given whale and propagation path. To accomplish this, features are extracted from pairs of clicks in order to derive a statistical measure of click similarity. Then, the algorithm maximizes a global measure of similarity between the associated clicks. In addition to grouping clicks according to click-trains, it classifies click-trains into a propagation path (direct, surface, bottom reverberation). The propagation path is identified using a combination of (1) a statistical classifier operating on features extracted from individual clicks and (2) the cross-correlation of click-trains to identify the relative time delays. The algorithm is demonstrated on at-sea recorded data, showing the elimination of time-delay ambiguities associated with the reverberation paths observed at sensor pairs.
Collapse
Affiliation(s)
- Paul M Baggenstoss
- Naval Undersea Warfare Center, 1176 Howell Street, Newport, Rhode Island 02841, USA.
| |
Collapse
|
55
|
Antunes R, Schulz T, Gero S, Whitehead H, Gordon J, Rendell L. Individually distinctive acoustic features in sperm whale codas. Anim Behav 2011. [DOI: 10.1016/j.anbehav.2010.12.019] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
56
|
CLAUSEN KARINTUBBERT, WAHLBERG MAGNUS, BEEDHOLM KRISTIAN, DERUITER STACY, MADSEN PETERTEGLBERG. CLICK COMMUNICATION IN HARBOUR PORPOISESPHOCOENA PHOCOENA. BIOACOUSTICS 2011. [DOI: 10.1080/09524622.2011.9753630] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
57
|
Madsen PT, Wisniewska D, Beedholm K. Single source sound production and dynamic beam formation in echolocating harbour porpoises (Phocoena phocoena). J Exp Biol 2010; 213:3105-10. [DOI: 10.1242/jeb.044420] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Echolocating toothed whales produce high-powered clicks by pneumatic actuation of phonic lips in their nasal complexes. All non-physeteroid toothed whales have two pairs of phonic lips allowing many of these species to produce both whistles and clicks at the same time. That has led to the hypothesis that toothed whales can increase the power outputs and bandwidths of clicks, and enable fast clicking and beam steering by acutely timed actuation of both phonic lip pairs simultaneously. Here we test that hypothesis by applying suction cup hydrophones on the sound-producing nasal complexes of three echolocating porpoises (Phocoena phocoena) with symmetrical pairs of phonic lips. Using time of arrival differences on three hydrophones, we show that all recorded clicks from these three porpoises are produced by the right pair of phonic lips with no evidence of simultaneous or independent actuation of the left pair. It is demonstrated that porpoises, despite actuation of only one sound source, can change their output and sound beam probably through conformation changes in the sound-producing soft tissues and nasal sacs, and that the coupling of the phonic lips and the melon acts as a waveguide for sound energy between 100 and 160 kHz to generate a forward-directed sound beam for echolocation.
Collapse
Affiliation(s)
- P. T. Madsen
- Zoophysiology, Department of Biological Sciences, Aarhus University, Build 1131, 8000 Aarhus C, Denmark
| | - D. Wisniewska
- Zoophysiology, Department of Biological Sciences, Aarhus University, Build 1131, 8000 Aarhus C, Denmark
| | - K. Beedholm
- Zoophysiology, Department of Biological Sciences, Aarhus University, Build 1131, 8000 Aarhus C, Denmark
| |
Collapse
|
58
|
Baumann-Pickering S, Wiggins SM, Roth EH, Roch MA, Schnitzler HU, Hildebrand JA. Echolocation signals of a beaked whale at Palmyra Atoll. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2010; 127:3790-3799. [PMID: 20550277 DOI: 10.1121/1.3409478] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Acoustic recordings from Palmyra Atoll, northern Line Islands, central Pacific, showed upsweep frequency modulated pulses reminiscent of those produced by beaked whales. These signals had higher frequencies, broader bandwidths, longer pulse durations and shorter inter-pulse intervals than previously described pulses of Blainville's, Cuvier's and Gervais' beaked whales [Zimmer et al. (2005). J. Acoust. Soc. Am. 117, 3919-3927; Johnson et al. (2006). J. Exp. Biol. 209, 5038-5050; Gillespie et al. (2009). J. Acoust. Soc. Am. 125, 3428-3433]. They were distinctly different temporally and spectrally from the unknown beaked whale at Cross Seamount, HI [McDonald et al. (2009). J. Acoust. Soc. Am. 125, 624-627]. Genetics on beaked whale specimens found at Palmyra Atoll suggest the presence of a poorly known beaked whale species. Mesoplodon sp. might be the source of the FM pulses described in this paper. The Palmyra Atoll FM pulse peak frequency was at 44 kHz with a -10 dB bandwidth of 26 kHz. Mean pulse duration was 355 mus and inter-pulse interval was 225 ms, with a bimodal distribution. Buzz sequences were detected with inter-pulse intervals below 20 ms and unmodulated spectra, with about 20 dB lower amplitude than prior FM pulses. These clicks had a 39 kHz bandwidth (-10 dB), peak frequency at 37 kHz, click duration 155 mus, and inter-click interval between 4 and 10 ms.
Collapse
Affiliation(s)
- Simone Baumann-Pickering
- Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Drive, La Jolla, California 92093-0205, USA.
| | | | | | | | | | | |
Collapse
|
59
|
Antunes R, Rendell L, Gordon J. Measuring inter-pulse intervals in sperm whale clicks: consistency of automatic estimation methods. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2010; 127:3239-3247. [PMID: 21117772 DOI: 10.1121/1.3327509] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Sperm whale clicks are characterized by a multi-pulsed structure. The time lag between consecutive pulses, i.e., the inter-pulse interval (IPI), is related to the size of the sound production organ such that its measurement provides a means to acoustically estimate the size of individual whales. Due to off-axis effects the identification of pulses is, however, not always straightforward, and automatic measurement methods provide not only more objective estimation, but may also facilitate IPI estimation in cases where single click measurements are ambiguous. In particular, averaging measurements over a time series of clicks from the same whale could enhance the discrimination of time invariant pulses. The authors developed two automatic methods of automatic IPI measurement based on waveform and autocorrelation averaging and compared their accuracy and consistency with other previously used methods. Manual measurement by an experienced operator provided the most self-consistent estimates. The autocorrelation averaging technique had the best overall performance of the automated methods achieving a very similar performance to manual measurement. On some recordings cepstrum averaging methods converged when autocorrelation did not. Therefore, applying both of these automated methods and choosing the best of the two are recommended.
Collapse
Affiliation(s)
- Ricardo Antunes
- Sea Mammal Research Unit, Scottish Oceans Institute, Gatty Marine Laboratory, University of St Andrews, St Andrews KY16 8LB, United Kingdom.
| | | | | |
Collapse
|
60
|
Hirotsu R, Yanagisawa M, Ura T, Sakata M, Sugimatsu H, Kojima J, Bahl R. Localization of sperm whales in a group using clicks received at two separated short baseline arrays. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2010; 127:133-147. [PMID: 20058957 DOI: 10.1121/1.3268593] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In this paper, a sperm whale click analysis scheme is proposed in order to calculate the position of individual sperm whales in a group using data received at two arrays deployed near the surface. The proposed method mainly consists of two parts: short baseline (SBL) with classification and long baseline (LBL) with class matching. In SBL with classification, a click is automatically detected, and its direction of arrival is calculated. The clicks are then classified based on their direction vectors. The class data are then sent together with direction data and matched to the other array's class data. LBL with class matching is used for localization. The classification algorithm can be used to estimate the number of whales clicking and to list potential candidates for LBL matching. As a result, the proposed method is able to localize the positions of the whales in a group. The performance of the proposed method is evaluated using data recorded off Ogasawara islands with two arrays near the surface. The three-dimensional underwater trajectories of six sperm whales are extracted to demonstrate the capability of the proposed method.
Collapse
Affiliation(s)
- Ryo Hirotsu
- Department of Computer Science, Waseda University, 3-4-1 Ohkubo, Shinjukuku, Tokyo 169-8555, Japan
| | | | | | | | | | | | | |
Collapse
|
61
|
DeRuiter SL, Bahr A, Blanchet MA, Hansen SF, Kristensen JH, Madsen PT, Tyack PL, Wahlberg M. Acoustic behaviour of echolocating porpoises during prey capture. J Exp Biol 2009; 212:3100-7. [DOI: 10.1242/jeb.030825] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Porpoise echolocation has been studied previously, mainly in target detection experiments using stationed animals and steel sphere targets, but little is known about the acoustic behaviour of free-swimming porpoises echolocating for prey. Here, we used small onboard sound and orientation recording tags to study the echolocation behaviour of free-swimming trained porpoises as they caught dead, freely drifting fish. We analysed porpoise echolocation behaviour leading up to and following prey capture events,including variability in echolocation in response to vision restriction, prey species, and individual porpoise tested. The porpoises produced echolocation clicks as they searched for the fish, followed by fast-repetition-rate clicks(echolocation buzzes) when acquiring prey. During buzzes, which usually began when porpoises were about 1–2 body lengths from prey, tag-recorded click levels decreased by about 10 dB, click rates increased to over 300 clicks per second, and variability in body orientation (roll) increased. Buzzes generally continued beyond the first contact with the fish, and often extended until or after the end of prey handling. This unexplained continuation of buzzes after prey capture raises questions about the function of buzzes, suggesting that in addition to providing detailed information on target location during the capture, they may serve additional purposes such as the relocation of potentially escaping prey. We conclude that porpoises display the same overall acoustic prey capture behaviour seen in larger toothed whales in the wild,albeit at a faster pace, clicking slowly during search and approach phases and buzzing during prey capture.
Collapse
Affiliation(s)
- Stacy L. DeRuiter
- IFREMER, Service Acoustique et Sismique, B.P. 70, 29280 Plouzané,France
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Alexander Bahr
- Massachusetts Institute of Technology, Center for Ocean Engineering, 32 Vassar Street, Cambridge, MA 02139, USA
| | | | | | | | - Peter T. Madsen
- Department of Biological Sciences, Zoophysiology, Aarhus University, C.F. Møllers Allé, Building 1131, DK-8000 Aarhus C, Denmark
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Peter L. Tyack
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Magnus Wahlberg
- Fjord and Baelt, Margrethes Plads 1, DK-5300 Kerteminde, Denmark
- Marine Biological Laboratory, University of Southern Denmark, Hindsholmsvej 10, 5300 Kerteminde, Denmark
| |
Collapse
|
62
|
Jensen FH, Bejder L, Wahlberg M, Madsen PT. Biosonar adjustments to target range of echolocating bottlenose dolphins(Tursiops sp.) in the wild. J Exp Biol 2009; 212:1078-86. [DOI: 10.1242/jeb.025619] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Toothed whales use echolocation to locate and track prey. Most knowledge of toothed whale echolocation stems from studies on trained animals, and little is known about how toothed whales regulate and use their biosonar systems in the wild. Recent research suggests that an automatic gain control mechanism in delphinid biosonars adjusts the biosonar output to the one-way transmission loss to the target, possibly a consequence of pneumatic restrictions in how fast the sound generator can be actuated and still maintain high outputs. This study examines the relationships between target range (R), click intervals,and source levels of wild bottlenose dolphins (Tursiops sp.) by recording regular (non-buzz) echolocation clicks with a linear hydrophone array. Dolphins clicked faster with decreasing distance to the array,reflecting a decreasing delay between the outgoing echolocation click and the returning array echo. However, for interclick intervals longer than 30–40 ms, source levels were not limited by the repetition rate. Thus,pneumatic constraints in the sound-production apparatus cannot account for source level adjustments to range as a possible automatic gain control mechanism for target ranges longer than a few body lengths of the dolphin. Source level estimates drop with reducing range between the echolocating dolphins and the target as a function of 17 log(R). This may indicate either(1) an active form of time-varying gain in the biosonar independent of click intervals or (2) a bias in array recordings towards a 20 log(R) relationship for apparent source levels introduced by a threshold on received click levels included in the analysis.
Collapse
Affiliation(s)
- F. H. Jensen
- Zoophysiology, Department of Biological Sciences, Aarhus University, 8000 Aarhus C, Denmark
| | - L. Bejder
- Murdoch University Cetacean Research Unit, Centre for Fish and Fisheries Research, Murdoch University, Perth, 6150 Western Australia
| | - M. Wahlberg
- Murdoch University Cetacean Research Unit, Centre for Fish and Fisheries Research, Murdoch University, Perth, 6150 Western Australia
- Fjord and Bælt and University of Southern Denmark, Margrethes Plads 1,5300 Kerteminde, Denmark
| | - P. T. Madsen
- Zoophysiology, Department of Biological Sciences, Aarhus University, 8000 Aarhus C, Denmark
- Murdoch University Cetacean Research Unit, Centre for Fish and Fisheries Research, Murdoch University, Perth, 6150 Western Australia
- Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| |
Collapse
|
63
|
Verfuß UK, Miller LA, Pilz PKD, Schnitzler HU. Echolocation by two foraging harbour porpoises (Phocoena phocoena). J Exp Biol 2009; 212:823-34. [DOI: 10.1242/jeb.022137] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Synchronized video and high-frequency audio recordings of two trained harbour porpoises searching for and capturing live fish were used to study swimming and echolocation behaviour. One animal repeated the tasks blindfolded. A splash generated by the fish being thrown into the pool or– in controls – by a boat hook indicated prey and stimulated search behaviour. The echolocation sequences were divided into search and approach phases. In the search phase the porpoises displayed a clear range-locking behaviour on landmarks, indicated by a distance-dependent decrease in click interval. Only in trials with fish was the search phase followed by an approach phase. In the initial part of the approach phase the porpoises used a rather constant click interval of around 50 ms. The terminal part started with a sudden drop in click interval at distances around 2–4 m. Close to the prey the terminal part ended with a buzz,characterized by constant click intervals around 1.5 ms. The lag time in the search and the initial part of the approach phase seems to be long enough for the porpoise to process echo information before emitting the next click (pulse mode). However, we assume that during the buzz lag times are too short for pulse mode processing and that distance information is perceived as a `pitch'with a `frequency' corresponding to the inverse of the two-way transit time(pitch mode). The swimming speed of the animal was halved when it was blindfolded, while the click intervals hardly changed, resulting in more clicks emitted per metre swum.
Collapse
Affiliation(s)
- Ursula K. Verfuß
- Fjord & Bælt, Margrethes Plads 1, DK-5300 Kerteminde, Denmark
- Tierphysiologie, Zoologisches Institut, Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
| | - Lee A. Miller
- Institute of Biology, University of Southern Denmark, DK-5230 Odense M,Denmark
| | - Peter K. D. Pilz
- Tierphysiologie, Zoologisches Institut, Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
| | - Hans-Ulrich Schnitzler
- Tierphysiologie, Zoologisches Institut, Universität Tübingen, Auf der Morgenstelle 28, D-72076 Tübingen, Germany
| |
Collapse
|
64
|
Schulz TM, Whitehead H, Rendell L. Off-axis effects on the multi-pulse structure of sperm whale coda clicks. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2009; 125:1768-1773. [PMID: 19275333 DOI: 10.1121/1.3075598] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Sperm whale (Physeter macrocephalus) clicks have a multi-pulse structure, a result of the reflection of sound energy between air sacs in the spermaceti organ. Although previous research revealed that usual clicks (used for echolocation) recorded away from a vocalizing whale's longitudinal axis have waveforms with poorly defined pulse structures, it has been unknown whether sperm whale coda clicks (used for communication) show similar off-axis effects. To address this knowledge gap, a hydrophone array was used to localize vocalizing sperm whales, and the waveforms of coda clicks recorded from different aspects were examined. Coda clicks recorded close to the whale's acoustic axis showed well-defined multi-pulsed waveforms, while those recorded off-axis did not. As for usual clicks, this suggests that sound energy radiates directly into the water upon reflection off the frontal sac.
Collapse
Affiliation(s)
- Tyler M Schulz
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada.
| | | | | |
Collapse
|
65
|
ATEM ANACAROLINAG, RASMUSSEN MARIANNEH, WAHLBERG MAGNUS, PETERSEN HANSC, MILLER LEEA. CHANGES IN CLICK SOURCE LEVELS WITH DISTANCE TO TARGETS: STUDIES OF FREE-RANGING WHITE-BEAKED DOLPHINSLAGENORHYNCHUS ALBIROSTRISAND CAPTIVE HARBOUR PORPOISESPHOCOENA PHOCOENA. BIOACOUSTICS 2009. [DOI: 10.1080/09524622.2009.9753614] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
66
|
Hansen M, Wahlberg M, Madsen PT. Low-frequency components in harbor porpoise (Phocoena phocoena) clicks: communication signal, by-products, or artifacts? THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2008; 124:4059. [PMID: 19206828 DOI: 10.1121/1.2945154] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Underwater sound signals for biosonar and communication normally have different source properties to serve the purposes of generating efficient acoustic backscatter from small objects or conveying information to conspecifics. Harbor porpoises (Phocoena phocoena) are nonwhistling toothed whales that produce directional, narrowband, high-frequency (HF) echolocation clicks. This study tests the hypothesis that their 130 kHz HF clicks also contain a low-frequency (LF) component more suited for communication. Clicks from three captive porpoises were analyzed to quantify the LF and HF source properties. The LF component is 59 (S.E.M=1.45 dB) dB lower than the HF component recorded on axis, and even at extreme off-axis angles of up to 135 degrees , the HF component is 9 dB higher than the LF component. Consequently, the active space of the HF component will always be larger than that of the LF component. It is concluded that the LF component is a by-product of the sound generator rather than a dedicated pulse produced to serve communication purposes. It is demonstrated that distortion and clipping in analog tape recorders can explain some of the prominent LF components reported in earlier studies, emphasizing the risk of erroneous classification of sound types based on recording artifacts.
Collapse
Affiliation(s)
- M Hansen
- Department of Biological Sciences, University of Aarhus, Denmark.
| | | | | |
Collapse
|
67
|
Aguilar Soto N, Johnson MP, Madsen PT, Díaz F, Domínguez I, Brito A, Tyack P. Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands). J Anim Ecol 2008; 77:936-47. [PMID: 18444999 DOI: 10.1111/j.1365-2656.2008.01393.x] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Natacha Aguilar Soto
- BIOECOMAC Department of Animal Biology, La Laguna University, Tenerife, Canary Islands, Spain.
| | | | | | | | | | | | | |
Collapse
|
68
|
Baumgartner MF, Van Parijs SM, Wenzel FW, Tremblay CJ, Carter Esch H, Warde AM. Low frequency vocalizations attributed to sei whales (Balaenoptera borealis). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2008; 124:1339-1349. [PMID: 18681619 DOI: 10.1121/1.2945155] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Low frequency (<100 Hz) downsweep vocalizations were repeatedly recorded from ocean gliders east of Cape Cod, MA in May 2005. To identify the species responsible for this call, arrays of acoustic recorders were deployed in this same area during 2006 and 2007. 70 h of collocated visual observations at the center of each array were used to compare the localized occurrence of this call to the occurrence of three baleen whale species: right, humpback, and sei whales. The low frequency call was significantly associated only with the occurrence of sei whales. On average, the call swept from 82 to 34 Hz over 1.4 s and was most often produced as a single call, although pairs and (more rarely) triplets were occasionally detected. Individual calls comprising the pairs were localized to within tens of meters of one another and were more similar to one another than to contemporaneous calls by other whales, suggesting that paired calls may be produced by the same animal. A synthetic kernel was developed to facilitate automatic detection of this call using spectrogram-correlation methods. The optimal kernel missed 14% of calls, and of all the calls that were automatically detected, 15% were false positives.
Collapse
Affiliation(s)
- Mark F Baumgartner
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543
| | | | | | | | | | | |
Collapse
|
69
|
Johnson M, Hickmott LS, Aguilar Soto N, Madsen PT. Echolocation behaviour adapted to prey in foraging Blainville's beaked whale (Mesoplodon densirostris). Proc Biol Sci 2008; 275:133-9. [PMID: 17986434 DOI: 10.1098/rspb.2007.1190] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Toothed whales echolocating in the wild generate clicks with low repetition rates to locate prey but then produce rapid sequences of clicks, called buzzes, when attempting to capture prey. However, little is known about the factors that determine clicking rates or how prey type and behaviour influence echolocation-based foraging. Here we study Blainville's beaked whales foraging in deep water using a multi-sensor DTAG that records both outgoing echolocation clicks and echoes returning from mesopelagic prey. We demonstrate that the clicking rate at the beginning of buzzes is related to the distance between whale and prey, supporting the presumption that whales focus on a specific prey target during the buzz. One whale showed a bimodal relationship between target range and clicking rate producing abnormally slow buzz clicks while attempting to capture large echoic targets, probably schooling prey, with echo duration indicating a school diameter of up to 4.3m. These targets were only found when the whale performed tight circling manoeuvres spending up to five times longer in water volumes with large targets than with small targets. The result indicates that toothed whales in the wild can adjust their echolocation behaviour and movement for capture of different prey on the basis of structural echo information.
Collapse
Affiliation(s)
- M Johnson
- Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
| | | | | | | |
Collapse
|
70
|
Frantzis A, Alexiadou P. Male sperm whale (Physeter macrocephalus) coda production and coda-type usage depend on the presence of conspecifics and the behavioural context. CAN J ZOOL 2008. [DOI: 10.1139/z07-114] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Sperm whale ( Physeter macrocephalus L., 1758 (= Physeter catodon L., 1758)) codas serve a communication function, but the message they carry remains unknown. Very few codas and extremely few coda types are available from males. For 7 years we studied the coda occurrence and the coda types produced by 15 males in different behavioural and encounter contexts. Of the 67 encounters, 615 codas were produced by nonsolitary males. Codas occurred in 60% of the nonsolitary encounters and 36% of the dive cycles. Four hundred and ninety codas have been categorized into 8 coda families and 25 distinctive coda types. Both the coda type used and the dive cycle phase in which codas occurred strongly depended on the behavioural context. This is the first time that coda types have been associated with particular behavioural contexts. The “Three plus” family coda types were mainly used by ascending or descending whales in feeding dive cycles. The “Regular” and “Progressive” families were used almost exclusively by interacting whales. The “Root” coda family was used exclusively at surface, mainly in altered dive cycles. The coda types used in these three behavioural contexts seem to carry different messages and are proposed to be named “dive cycle codas”, “social codas”, and “alarm codas”, respectively.
Collapse
Affiliation(s)
- Alexandros Frantzis
- Pelagos Cetacean Research Institute, Terpsichoris 21, 16671 Vouliagmeni, Greece
| | - Paraskevi Alexiadou
- Pelagos Cetacean Research Institute, Terpsichoris 21, 16671 Vouliagmeni, Greece
| |
Collapse
|
71
|
Cranford TW, Mckenna MF, Soldevilla MS, Wiggins SM, Goldbogen JA, Shadwick RE, Krysl P, St. Leger JA, Hildebrand JA. Anatomic Geometry of Sound Transmission and Reception in Cuvier's Beaked Whale (Ziphius cavirostris). Anat Rec (Hoboken) 2008; 291:353-78. [DOI: 10.1002/ar.20652] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
72
|
Nosal EM, Frazer LN. Sperm whale three-dimensional track, swim orientation, beam pattern, and click levels observed on bottom-mounted hydrophones. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2007; 122:1969-78. [PMID: 17902833 DOI: 10.1121/1.2775423] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
In an earlier paper [Nosal and Frazer Appl. Acoust. 61, 1187-1201 (2006)], a sperm whale was tracked in three-dimensions using direct and surface-reflected time differences (DRTD) of clicks recorded on five bottom-mounted hydrophones, a passive method that is robust to timing errors between hydrophones. This paper refines the DRTD method and combines it with a time of (direct) arrival method to improve the accuracy of the track. The position and origin time of each click having been estimated, pitch and yaw are then obtained by assuming the main axis of the whale is tangent to the track. Roll is then found by applying the bent horn model of sperm whale phonation, in which each click is composed of two pulses, p0 and p1, that exit the whale at different points. With instantaneous pitch, roll, and yaw estimated from time differences, amplitudes are then used to estimate the beam patterns of the p0 and p1 pulses. The resulting beam patterns independently confirm those obtained by Zimmer et al. [J. Acoust. Soc. Am. 117, 1473-1485 (2005); 118, 3337-3345 (2005)] with a very different experimental setup. A method for estimating relative click levels is presented and used to find that click levels decrease toward the end of a click series, prior to the "creak" associated with prey capture.
Collapse
Affiliation(s)
- Eva-Marie Nosal
- School of Ocean and Earth Science and Technology, University of Hawaii, Honolulu, Hawaii 96822, USA.
| | | |
Collapse
|
73
|
Cooke SJ, Hinch SG, Wikelski M, Andrews RD, Kuchel LJ, Wolcott TG, Butler PJ. Biotelemetry: a mechanistic approach to ecology. Trends Ecol Evol 2007; 19:334-43. [PMID: 16701280 DOI: 10.1016/j.tree.2004.04.003] [Citation(s) in RCA: 363] [Impact Index Per Article: 21.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Remote measurement of the physiology, behaviour and energetic status of free-living animals is made possible by a variety of techniques that we refer to collectively as 'biotelemetry'. This set of tools ranges from transmitters that send their signals to receivers up to a few kilometers away to those that send data to orbiting satellites and, more frequently, to devices that log data. They enable researchers to document, for long uninterrupted periods, how undisturbed organisms interact with each other and their environment in real time. In spite of advances enabling the monitoring of many physiological and behavioural variables across a range of taxa of various sizes, these devices have yet to be embraced widely by the ecological community. Our review suggests that this technology has immense potential for research in basic and applied animal ecology. Efforts to incorporate biotelemetry into broader ecological research programs should yield novel information that has been challenging to collect historically from free-ranging animals in their natural environments. Examples of research that would benefit from biotelemetry include the assessment of animal responses to different anthropogenic perturbations and the development of life-time energy budgets.
Collapse
Affiliation(s)
- Steven J Cooke
- Centre for Applied Conservation Research, Department of Forest Sciences, University of British Columbia, 2424 Main Mall, Vancouver, BC, Canada, V6T 1Z4.
| | | | | | | | | | | | | |
Collapse
|
74
|
Laplanche C, Adam O, Lopatka M, Motsch JF. Measuring the off-axis angle and the rotational movements of phonating sperm whales using a single hydrophone. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2006; 119:4074-82. [PMID: 16838549 DOI: 10.1121/1.2184987] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The common use of the bent-horn model of the sperm whale sound generator describes sperm whale clicks as the pulse series {p0, p1, p2, p3,...}. Clicks, however, deviate from this standard when recorded using off-axis hydrophones. The existence of additional pulses within the {p0, p1, p2, p3, ...} series can be explained still using the bent-horn model. Multiple reflections on the whale's frontal and distal sacs of the p0 pulse lead to additional sets of pulses detectable using a farfield, off-axis hydrophone. The travel times of some of these additional pulses depend on the whale's orientation. The authors propose a method to estimate the off-axis angle of sperm whale clicks. They also propose a method to determine the nature of the movement (if it is pitch, yaw, or roll) of phonating sperm whales. The application of both methods requires the measurement of the travel time differences between pulses composing a sperm whale click. They lead, using a simple apparatus consisting of a single hydrophone at an unknown depth, to new measurements of the underwater movements of sperm whales. Using these methods shows that sperm whales would methodically scan seawater while searching for prey, by making periodic pitch and yaw movements in sync with their acoustic activity.
Collapse
Affiliation(s)
- Christophe Laplanche
- Laboratoire Images, Signaux et Systémes Intelligents, Groupe Ingénierie des Signaux Neuro-Sensoriels, Université Paris XII, France.
| | | | | | | |
Collapse
|
75
|
Marcoux M, Whitehead H, Rendell L. Coda vocalizations recorded in breeding areas are almost entirely produced by mature female sperm whales (Physeter macrocephalus). CAN J ZOOL 2006. [DOI: 10.1139/z06-035] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We investigated the use and function of coda communication by sperm whales ( Physeter macrocephalus L., 1758 (= Physeter catodon L., 1758)). Codas are stereotyped patterns of clicks often made by sperm whales in social contexts. We used the pulsed structure of coda clicks recorded from socializing female/immature groups to estimate the body-length distribution of the animals producing the codas. Ninety-five percent of the 10 653 codas that we measured were produced by whales measuring from 9 to 11 m. This size range corresponds to the lengths of mature females. We compared these data to a length distribution calculated from photographic measurements of individuals from the same groups encountered during the same studies. There were more whales shorter than 8.5 m (10.0%) and longer than 12.5 m (2.7%) in the photographic length distribution than in that of the coda producers (0.30% and 0.08%, respectively). Since males leave their natal group when they are shorter than 9 m and return to breeding areas when they measure 13 m or more, our data show that the codas were produced almost entirely by mature females. We suggest that coda communication serves several functions, including social bonding.
Collapse
Affiliation(s)
- Marianne Marcoux
- Department of Biology, Dalhousie University, Halifax, NS B3H 4J1, Canada
- Sea Mammal Research Unit, School of Biology, University of St. Andrews, St. Andrews, Fife KY16 8LB, UK
| | - Hal Whitehead
- Department of Biology, Dalhousie University, Halifax, NS B3H 4J1, Canada
- Sea Mammal Research Unit, School of Biology, University of St. Andrews, St. Andrews, Fife KY16 8LB, UK
| | - Luke Rendell
- Department of Biology, Dalhousie University, Halifax, NS B3H 4J1, Canada
- Sea Mammal Research Unit, School of Biology, University of St. Andrews, St. Andrews, Fife KY16 8LB, UK
| |
Collapse
|
76
|
Bradshaw CJA, Evans K, Hindell MA. Mass cetacean strandings-a plea for empiricism. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2006; 20:584-6. [PMID: 16903122 DOI: 10.1111/j.1523-1739.2006.00329.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Affiliation(s)
- Corey J A Bradshaw
- School for Environmental Research, Charles Darwin University, Darwin, Northern Territory 0909, Australia.
| | | | | |
Collapse
|
77
|
Wahlberg M, Frantzis A, Alexiadou P, Madsen PT, Møhl B. Click production during breathing in a sperm whale (Physeter macrocephalus). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 118:3404-7. [PMID: 16419786 DOI: 10.1121/1.2126930] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
A sperm whale (Physeter macrocephalus) was observed at the surface with above- and underwater video and synchronized underwater sound recordings. During seven instances the whale ventilated its lungs while clicking. From this observation it is inferred that click production is achieved by pressurizing air in the right nasal passage, pneumatically disconnected from the lungs and the left nasal passage, and that air flows anterior through the phonic lips into the distal air sac. The capability of breathing and clicking at the same time is unique among studied odontocetes and relates to the extreme asymmetry of the sperm whale sound-producing forehead.
Collapse
Affiliation(s)
- Magnus Wahlberg
- Department of Zoophysiology, Aarhus University, C. F. Møllers Alle Building 131, DK-8000 Aarhus C, Denmark
| | | | | | | | | |
Collapse
|
78
|
Zimmer WMX, Madsen PT, Teloni V, Johnson MP, Tyack PL. Off-axis effects on the multipulse structure of sperm whale usual clicks with implications for sound production. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 118:3337-45. [PMID: 16334703 DOI: 10.1121/1.2082707] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Sperm whales (Physeter macrocephalus) produce multipulsed clicks with their hypertrophied nasal complex. The currently accepted view of the sound generation process is based on the click structure measured directly in front of, or behind, the whale where regular interpulse intervals (IPIs) are found between successive pulses in the click. Most sperm whales, however, are recorded with the whale in an unknown orientation with respect to the hydrophone where the multipulse structure and the IPI do not conform to a regular pulse pattern. By combining far-field recordings of usual clicks with acoustic and orientation information measured by a tag on the clicking whale, we analyzed clicks from known aspects to the whale. We show that a geometric model based on the bent horn theory for sound production can explain the varying off-axis multipulse structure. Some of the sound energy that is reflected off the frontal sac radiates directly into the water creating an intermediate pulse p1/2 seen in off-axis recordings. The powerful p1 sonar pulse exits the front of the junk as predicted by the bent-horn model, showing that the junk of the sperm whale nasal complex is both anatomically and functionally homologous to the melon of smaller toothed whales.
Collapse
Affiliation(s)
- Walter M X Zimmer
- NATO Undersea Research Centre, V.le San Bartolomeo 400, I-19138 La Spezia, Italy.
| | | | | | | | | |
Collapse
|
79
|
Laplanche C, Adam O, Lopatka M, Motsch JF. Male sperm whale acoustic behavior observed from multipaths at a single hydrophone. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 118:2677-87. [PMID: 16266187 DOI: 10.1121/1.2033567] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Sperm whales generate transient sounds (clicks) when foraging. These clicks have been described as echolocation sounds, a result of having measured the source level and the directionality of these signals and having extrapolated results from biosonar tests made on some small odontocetes. The authors propose a passive acoustic technique requiring only one hydrophone to investigate the acoustic behavior of free-ranging sperm whales. They estimate whale pitch angles from the multipath distribution of click energy. They emphasize the close bond between the sperm whale's physical and acoustic activity, leading to the hypothesis that sperm whales might, like some small odontocetes, control click level and rhythm. An echolocation model estimating the range of the sperm whale's targets from the interclick interval is computed and tested during different stages of the whale's dive. Such a hypothesis on the echolocation process would indicate that sperm whales echolocate their prey layer when initiating their dives and follow a methodic technique when foraging.
Collapse
Affiliation(s)
- Christophe Laplanche
- Laboratoire Images, Signaux et Systèmes Intelligents Groupe ingénierie des Signaux Neuro-Sensoriels, Université Paris XII, France.
| | | | | | | |
Collapse
|
80
|
Abstract
Detecting objects in their paths is a fundamental perceptional function of moving organisms. Potential risks and rewards, such as prey, predators, conspecifics or non-biological obstacles, must be detected so that an animal can modify its behaviour accordingly. However, to date few studies have considered how animals in the wild focus their attention. Dolphins and porpoises are known to actively use sonar or echolocation. A newly developed miniature data logger attached to a porpoise allows for individual recording of acoustical search efforts and inspection distance based on echolocation. In this study, we analysed the biosonar behaviour of eight free-ranging finless porpoises (Neophocaena phocaenoides) and demonstrated that these animals inspect the area ahead of them before swimming silently into it. The porpoises inspected distances up to 77 m, whereas their swimming distance without using sonar was less than 20 m. The inspection distance was long enough to ensure a wide safety margin before facing real risks or rewards. Once a potential prey item was detected, porpoises adjusted their inspection distance from the remote target throughout their approach.
Collapse
Affiliation(s)
- Tomonari Akamatsu
- National Research Institute of Fisheries Engineering, Kashima, Ibaraki 314-0421, Japan.
| | | | | | | |
Collapse
|
81
|
Douglas LA, Dawson SM, Jaquet N. Click rates and silences of sperm whales at Kaikoura, New Zealand. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 118:523-9. [PMID: 16119371 DOI: 10.1121/1.1937283] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Analysis of the usual click rates of sperm whales (Physeter macrocephalus) at Kaikoura, New Zealand, confirms the potential for assessing abundance via "click counting." Usual click rates over three dive cycles each of three photographically identified whales showed that 5 min averages of usual click rate did not differ significantly within dives, among dives of the same whale or among whales. Over the nine dives (n= 13 728 clicks) mean usual click rate was 1.272 clicks s(-1) (95% CI= 0.151). On average, individual sperm whales at Kaikoura spent 60% of their time usual clicking in winter and in summer. There was no evidence that whale identity or stage of the dive recorded affects significantly the percentage of time spent usual clicking. Differences in vocal behavior among sperm whale populations worldwide indicate that estimates of abundance that are based on click rates need to based on data from the population of interest, rather than from another population or some global average.
Collapse
Affiliation(s)
- Lesley A Douglas
- Department of Marine Science, University of Otago, PO Box 56, Dunedin, New Zealand
| | | | | |
Collapse
|
82
|
Zimmer WMX, Tyack PL, Johnson MP, Madsen PT. Three-dimensional beam pattern of regular sperm whale clicks confirms bent-horn hypothesis. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2005; 117:1473-1485. [PMID: 15807035 DOI: 10.1121/1.1828501] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The three-dimensional beam pattern of a sperm whale (Physeter macrocephalus) tagged in the Ligurian Sea was derived using data on regular clicks from the tag and from hydrophones towed behind a ship circling the tagged whale. The tag defined the orientation of the whale, while sightings and beamformer data were used to locate the whale with respect to the ship. The existence of a narrow, forward-directed P1 beam with source levels exceeding 210 dBpeak re: 1 microPa at 1 m is confirmed. A modeled forward-beam pattern, that matches clicks >20 degrees off-axis, predicts a directivity index of 26.7 dB and source levels of up to 229 dBpeak re: 1 microPa at 1 m. A broader backward-directed beam is produced by the P0 pulse with source levels near 200 dBpeak re: 1 microPa at 1 m and a directivity index of 7.4 dB. A low-frequency component with source levels near 190 dBpeak re: 1 microPa at 1 m is generated at the onset of the P0 pulse by air resonance. The results support the bent-horn model of sound production in sperm whales. While the sperm whale nose appears primarily adapted to produce an intense forward-directed sonar signal, less-directional click components convey information to conspecifics, and give rise to echoes from the seafloor and the surface, which may be useful for orientation during dives.
Collapse
Affiliation(s)
- Walter M X Zimmer
- NATO Undersea Research Centre, Vle San Bartolomeo 400, 19138 La Spezia, Italy
| | | | | | | |
Collapse
|
83
|
Miller PJO, Johnson MP, Tyack PL. Sperm whale behaviour indicates the use of echolocation click buzzes "creaks" in prey capture. Proc Biol Sci 2005; 271:2239-47. [PMID: 15539349 PMCID: PMC1691849 DOI: 10.1098/rspb.2004.2863] [Citation(s) in RCA: 198] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
During foraging dives, sperm whales (Physeter macrocephalus) produce long series of regular clicks at 0.5-2 s intervals interspersed with rapid-click buzzes called "creaks". Sound, depth and orientation recording Dtags were attached to 23 whales in the Ligurian Sea and Gulf of Mexico to test whether the behaviour of diving sperm whales supports the hypothesis that creaks are produced during prey capture. Sperm whales spent most of their bottom time within one or two depth bands, apparently feeding in vertically stratified prey layers. Creak rates were highest during the bottom phase: 99.8% of creaks were produced in the deepest 50% of dives, 57% in the deepest 15% of dives. Whales swam actively during the bottom phase, producing a mean of 12.5 depth inflections per dive. A mean of 32% of creaks produced during the bottom phase occurred within 10 s of an inflection (13x more than chance). Sperm whales actively altered their body orientation throughout the bottom phase with significantly increased rates of change during creaks, reflecting increased manoeuvring. Sperm whales increased their bottom foraging time when creak rates were higher. These results all strongly support the hypothesis that creaks are an echolocation signal adapted for foraging, analogous to terminal buzzes in taxonomically diverse echolocating species.
Collapse
Affiliation(s)
- Patrick J O Miller
- NERC Sea Mammal Research Unit, School of Biology, University of St Andrews, St Andrews KY16 9QQ, UK.
| | | | | |
Collapse
|
84
|
Madsen PT, Johnson M, de Soto NA, Zimmer WMX, Tyack P. Biosonar performance of foraging beaked whales (Mesoplodon densirostris). J Exp Biol 2005; 208:181-94. [PMID: 15634839 DOI: 10.1242/jeb.01327] [Citation(s) in RCA: 222] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARYToothed whales (Cetacea, odontoceti) emit sound pulses to probe their surroundings by active echolocation. Non-invasive, acoustic Dtags were placed on deep-diving Blainville's beaked whales (Mesoplodon densirostris) to record their ultrasonic clicks and the returning echoes from prey items, providing a unique view on how a whale operates its biosonar during foraging in the wild. The process of echolocation during prey capture in this species can be divided into search, approach and terminal phases, as in echolocating bats. The approach phase, defined by the onset of detectable echoes recorded on the tag for click sequences terminated by a buzz, has interclick intervals (ICI) of 300-400 ms. These ICIs are more than a magnitude longer than the decreasing two-way travel time to the targets, showing that ICIs are not given by the two-way-travel times plus a fixed, short lag time. During the approach phase, the received echo energy increases by 10.4(±2) dB when the target range is halved, demonstrating that the whales do not employ range-compensating gain control of the transmitter, as has been implicated for some bats and dolphins. The terminal/buzz phase with ICIs of around 10 ms is initiated when one or more targets are within approximately a body length of the whale (2-5 m), so that strong echo returns in the approach phase are traded for rapid updates in the terminal phase. It is suggested that stable ICIs in the search and approach phases facilitate auditory scene analysis in a complex multi-target environment, and that a concomitant low click rate allows the whales to maintain high sound pressure outputs for prey detection and discrimination with a pneumatically driven,bi-modal sound generator.
Collapse
Affiliation(s)
- P T Madsen
- Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
| | | | | | | | | |
Collapse
|
85
|
|
86
|
MADSEN PT, CARDER DA, BEDHOLM K, RIDGWAY SH. PORPOISE CLICKS FROM A SPERM WHALE NOSE—CONVERGENT EVOLUTION OF 130 KHZ PULSES IN TOOTHED WHALE SONARS? BIOACOUSTICS 2005. [DOI: 10.1080/09524622.2005.9753547] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
87
|
Miller PJO, Johnson MP, Tyack PL, Terray EA. Swimming gaits, passive drag and buoyancy of diving sperm whales Physeter macrocephalus. ACTA ACUST UNITED AC 2004; 207:1953-67. [PMID: 15107448 DOI: 10.1242/jeb.00993] [Citation(s) in RCA: 181] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Drag and buoyancy are two primary external forces acting on diving marine mammals. The strength of these forces modulates the energetic cost of movement and may influence swimming style (gait). Here we use a high-resolution digital tag to record depth, 3-D orientation, and sounds heard and produced by 23 deep-diving sperm whales in the Ligurian Sea and Gulf of Mexico. Periods of active thrusting versus gliding were identified through analysis of oscillations measured by a 3-axis accelerometer. Accelerations during 382 ascent glides of five whales (which made two or more steep ascents and for which we obtained a measurement of length) were strongly affected by depth and speed at Reynold's numbers of 1.4-2.8x10(7). The accelerations fit a model of drag, air buoyancy and tissue buoyancy forces with an r(2) of 99.1-99.8% for each whale. The model provided estimates (mean +/- S.D.) of the drag coefficient (0.00306+/-0.00015), air carried from the surface (26.4+/-3.9 l kg(-3) mass), and tissue density (1030+/-0.8 kg m(-3)) of these five animals. The model predicts strong positive buoyancy forces in the top 100 m of the water column, decreasing to near neutral buoyancy at 250-850 m. Mean descent speeds (1.45+/-0.19 m s(-1)) were slower than ascent speeds (1.63+/-0.22 m s(-1)), even though sperm whales stroked steadily (glides 5.3+/-6.3%) throughout descents and employed predominantly stroke-and-glide swimming (glides 37.7+/-16.4%) during ascents. Whales glided more during portions of dives when buoyancy aided their movement, and whales that glided more during ascent glided less during descent (and vice versa), supporting the hypothesis that buoyancy influences behavioural swimming decisions. One whale rested at approximately 10 m depth for more than 10 min without fluking, regulating its buoyancy by releasing air bubbles.
Collapse
Affiliation(s)
- Patrick J O Miller
- Sea Mammal Research Unit, University of St Andrews, Fife, KY16 8LB, Scotland.
| | | | | | | |
Collapse
|
88
|
Thode A. Tracking sperm whale (Physeter macrocephalus) dive profiles using a towed passive acoustic array. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2004; 116:245-253. [PMID: 15295984 DOI: 10.1121/1.1758972] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A passive acoustic method is presented for tracking sperm whale dive profiles, using two or three hydrophones deployed as either a vertical or large-aperture towed array. The relative arrival times between the direct and surface-reflected acoustic paths are used to obtain the ranges and depths of animals with respect to the array, provided that the hydrophone depths are independently measured. Besides reducing the number of hydrophones required, exploiting surface reflections simplifies automation of the data processing. Experimental results are shown from 2002 and 2003 cruises in the Gulf of Mexico for two different towed array deployments. The 2002 deployment consisted of two short-aperture towed arrays separated by 170 m, while the 2003 deployment placed an autonomous acoustic recorder in tandem with a short-aperture towed array, and used ship noise to time-align the acoustic data. The resulting dive profiles were independently checked using single-hydrophone localizations, whenever multipath reflections from the ocean bottom could be exploited to effectively create a large-aperture vertical array. This technique may have applications for basic research and for real-time mitigation for seismic airgun surveys.
Collapse
Affiliation(s)
- Aaron Thode
- Marine Physical Laboratory, Scripps Institution of Oceanography, San Diego, California 92093-0205, USA.
| |
Collapse
|
89
|
Rendell L, Whitehead H. Do sperm whales share coda vocalizations? Insights into coda usage from acoustic size measurement. Anim Behav 2004. [DOI: 10.1016/j.anbehav.2003.04.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
90
|
Madsen PT, Kerr I, Payne R. Echolocation clicks of two free-ranging, oceanic delphinids with different food preferences: false killer whales Pseudorca crassidensand Risso's dolphins Grampus griseus. J Exp Biol 2004; 207:1811-23. [PMID: 15107437 DOI: 10.1242/jeb.00966] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
SUMMARY
Toothed whales (Odontoceti, Cetacea) navigate and locate prey by means of active echolocation. Studies on captive animals have accumulated a large body of knowledge concerning the production, reception and processing of sound in odontocete biosonars, but there is little information about the properties and use of biosonar clicks of free-ranging animals in offshore habitats. This study presents the first source parameter estimates of biosonar clicks from two free-ranging oceanic delphinids, the opportunistically foraging Pseudorca crassidens and the cephalopod eating Grampus griseus. Pseudorca produces short duration (30 μs), broadband(Q=2–3) signals with peak frequencies around 40 kHz, centroid frequencies of 30–70 kHz, and source levels between 201–225 dB re. 1 μPa (peak to peak, pp). Grampus also produces short (40 μs),broadband (Q=2–3) signals with peak frequencies around 50 kHz,centroid frequencies of 60–90 kHz, and source levels between 202 and 222 dB re. 1 μPa (pp). On-axis clicks from both species had centroid frequencies in the frequency range of most sensitive hearing, and lower peak frequencies and higher source levels than reported from captive animals. It is demonstrated that sound production in these two free-ranging echolocators is dynamic, and that free-ranging animals may not always employ biosonar signals comparable to the extreme signal properties reported from captive animals in long-range detection tasks. Similarities in source parameters suggest that evolutionary factors other than prey type determine the properties of biosonar signals of the two species. Modelling shows that interspecific detection ranges of prey types differ from 80 to 300 m for Grampus and Pseudorca, respectively.
Collapse
Affiliation(s)
- P T Madsen
- Ocean Alliance, 191 Western Road, Lincoln, MA 01773, USA.
| | | | | |
Collapse
|
91
|
Møhl B, Wahlberg M, Madsen PT, Heerfordt A, Lund A. The monopulsed nature of sperm whale clicks. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2003; 114:1143-1154. [PMID: 12942991 DOI: 10.1121/1.1586258] [Citation(s) in RCA: 160] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Traditionally, sperm whale clicks have been described as multipulsed, long duration, nondirectional signals of moderate intensity and with a spectrum peaking below 10 kHz. Such properties are counterindicative of a sonar function, and quite different from the properties of dolphin sonar clicks. Here, data are presented suggesting that the traditional view of sperm whale clicks is incomplete and derived from off-axis recordings of a highly directional source. A limited number of assumed on-axis clicks were recorded and found to be essentially monopulsed clicks, with durations of 100 micros, with a composite directionality index of 27 dB, with source levels up to 236 dB re: 1 microPa (rms), and with centroid frequencies of 15 kHz. Such clicks meet the requirements for long-range biosonar purposes. Data were obtained with a large-aperture, GPS-synchronized array in July 2000 in the Bleik Canyon off Vesterålen, Norway (69 degrees 28' N, 15 degrees 40' E). A total of 14 h of sound recordings was collected from five to ten independent, simultaneously operating recording units. The sound levels measured make sperm whale clicks by far the loudest of sounds recorded from any biological source. On-axis click properties support previous work proposing the nose of sperm whales to operate as a generator of sound.
Collapse
Affiliation(s)
- Bertel Møhl
- Department of Zoophysiology, Institute of Biological Sciences, University of Aarhus, DK-8000 Aarhus C, Denmark.
| | | | | | | | | |
Collapse
|
92
|
Madsen PT, Carder DA, Au WWL, Nachtigall PE, Møhl B, Ridgway SH. Sound production in neonate sperm whales. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2003; 113:2988-2991. [PMID: 12822769 DOI: 10.1121/1.1572137] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
|