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Zeh JM, Adcock DL, Perez-Marrufo V, Cusano DA, Robbins J, Tackaberry JE, Jensen FH, Weinrich M, Friedlaender AS, Wiley DN, Parks SE. Acoustic behavior of humpback whale calves on the feeding ground: Comparisons across age and implications for vocal development. PLoS One 2024; 19:e0303741. [PMID: 38809930 PMCID: PMC11135678 DOI: 10.1371/journal.pone.0303741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 04/30/2024] [Indexed: 05/31/2024] Open
Abstract
Studying sound production at different developmental stages can provide insight into the processes involved in vocal ontogeny. Humpback whales (Megaptera novaeangliae) are a known vocal learning species, but their vocal development is poorly understood. While studies of humpback whale calves in the early stages of their lives on the breeding grounds and migration routes exist, little is known about the behavior of these immature, dependent animals by the time they reach the feeding grounds. In this study, we used data from groups of North Atlantic humpback whales in the Gulf of Maine in which all members were simultaneously carrying acoustic recording tags attached with suction cups. This allowed for assignment of likely caller identity using the relative received levels of calls across tags. We analyzed data from 3 calves and 13 adults. There were high levels of call rate variation among these individuals and the results represent preliminary descriptions of calf behavior. Our analysis suggests that, in contrast to the breeding grounds or on migration, calves are no longer acoustically cryptic by the time they reach their feeding ground. Calves and adults both produce calls in bouts, but there may be some differences in bout parameters like inter-call intervals and bout durations. Calves were able to produce most of the adult vocal repertoire but used different call types in different proportions. Finally, we found evidence of immature call types in calves, akin to protosyllables used in babbling in other mammals, including humans. Overall, the sound production of humpback whale calves on the feeding grounds appears to be already similar to that of adults, but with differences in line with ontogenetic changes observed in other vocal learning species.
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Affiliation(s)
- Julia M. Zeh
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
| | - Dana L. Adcock
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
| | - Valeria Perez-Marrufo
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
| | - Dana A. Cusano
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
| | - Jooke Robbins
- Center for Coastal Studies, Provincetown, Massachusetts, United States of America
| | | | - Frants H. Jensen
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
- Department of Ecoscience, Aarhus University, Roskilde, Denmark
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, United States of America
| | - Mason Weinrich
- Whale Center of New England, Gloucester, Massachusetts, United States of America
| | - Ari S. Friedlaender
- Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, California, United States of America
| | - David N. Wiley
- Stellwagen Bank National Marine Sanctuary, Scituate, Massachusetts, United States of America
| | - Susan E. Parks
- Department of Biology, Syracuse University, Syracuse, New York, United States of America
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2
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Sharma P, Gero S, Payne R, Gruber DF, Rus D, Torralba A, Andreas J. Contextual and combinatorial structure in sperm whale vocalisations. Nat Commun 2024; 15:3617. [PMID: 38714699 PMCID: PMC11076547 DOI: 10.1038/s41467-024-47221-8] [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: 01/23/2024] [Accepted: 03/25/2024] [Indexed: 05/10/2024] Open
Abstract
Sperm whales (Physeter macrocephalus) are highly social mammals that communicate using sequences of clicks called codas. While a subset of codas have been shown to encode information about caller identity, almost everything else about the sperm whale communication system, including its structure and information-carrying capacity, remains unknown. We show that codas exhibit contextual and combinatorial structure. First, we report previously undescribed features of codas that are sensitive to the conversational context in which they occur, and systematically controlled and imitated across whales. We call these rubato and ornamentation. Second, we show that codas form a combinatorial coding system in which rubato and ornamentation combine with two context-independent features we call rhythm and tempo to produce a large inventory of distinguishable codas. Sperm whale vocalisations are more expressive and structured than previously believed, and built from a repertoire comprising nearly an order of magnitude more distinguishable codas. These results show context-sensitive and combinatorial vocalisation can appear in organisms with divergent evolutionary lineage and vocal apparatus.
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Grants
- This analysis was funded by Project CETI via grants from Dalio Philanthropies and Ocean X; Sea Grape Foundation; Virgin Unite, Rosamund Zander/Hansjorg Wyss, Chris Anderson/Jacqueline Novogratz through The Audacious Project: a collaborative funding initiative housed at TED to PS, SG, RP, DFG, DR, AT and JA. Further funding was provided by the J.H.\ and E.V.\ Wade Fund at MIT. Fieldwork for The Dominica Sperm Whale Project was supported by through a FNU fellowship for the Danish Council for Independent Research supplemented by a Sapere Aude Research Talent Award (1325-00047A), a Carlsberg Foundation expedition grant (CF14-0789), two Explorer Grants from the National Geographic Society (WW-218R-17 and NGS-64863R-19), a grant from Focused on Nature, and supplementary grants from the Arizona Center for Nature Conservation, Quarters For Conservation, the Dansk Akustisks Selskab, Oticon Foundation, and the Dansk Tennis Fond all to SG. Further funding was provided by a Discovery and Equipment grants from the Natural Sciences and Engineering Research Council of Canada (NSERC) to Hal Whitehead of Dalhousie University and a FNU large frame grant and a Villum Foundation Grant (13273) to Peter Madsen of Aarhus University.
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Affiliation(s)
- Pratyusha Sharma
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA
- Project CETI, New York, NY, USA
| | - Shane Gero
- Project CETI, New York, NY, USA
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, ON, K1S 5B6, Canada
- The Dominica Sperm Whale Project, Roseau, Dominica
| | | | - David F Gruber
- Project CETI, New York, NY, USA
- Baruch College and The Graduate Center, City University of New York, New York, NY, USA
| | - Daniela Rus
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Project CETI, New York, NY, USA.
| | - Antonio Torralba
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Project CETI, New York, NY, USA.
| | - Jacob Andreas
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Project CETI, New York, NY, USA.
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3
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Barkley YM, Merkens KPB, Wood M, Oleson EM, Marques TA. Click detection rate variability of central North Pacific sperm whales from passive acoustic towed arrays. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2024; 155:2627-2635. [PMID: 38629884 DOI: 10.1121/10.0025540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 03/19/2024] [Indexed: 04/19/2024]
Abstract
Passive acoustic monitoring (PAM) is an optimal method for detecting and monitoring cetaceans as they frequently produce sound while underwater. Cue counting, counting acoustic cues of deep-diving cetaceans instead of animals, is an alternative method for density estimation, but requires an average cue production rate to convert cue density to animal density. Limited information about click rates exists for sperm whales in the central North Pacific Ocean. In the absence of acoustic tag data, we used towed hydrophone array data to calculate the first sperm whale click rates from this region and examined their variability based on click type, location, distance of whales from the array, and group size estimated by visual observers. Our findings show click type to be the most important variable, with groups that include codas yielding the highest click rates. We also found a positive relationship between group size and click detection rates that may be useful for acoustic predictions of group size in future studies. Echolocation clicks detected using PAM methods are often the only indicator of deep-diving cetacean presence. Understanding the factors affecting their click rates provides important information for acoustic density estimation.
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Affiliation(s)
- Yvonne M Barkley
- Cooperative Institute for Marine and Atmospheric Research, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Honolulu, Hawaii 96822, USA
| | | | - Megan Wood
- Saltwater Inc., Anchorage, Alaska 99501, USA
| | - Erin M Oleson
- Pacific Islands Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Honolulu, Hawaii 96818, USA
| | - Tiago A Marques
- Centre for Research into Ecological and Environmental Modelling, The Observatory, University of St Andrews, St Andrews, KY16 9LZ, Scotland
- Departamento de Biologia Animal, Centro de Estatística e Aplicações, Faculdade de Ciências da Universidade de Lisboa, Portugal
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4
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Zeh JM, Perez-Marrufo V, Adcock DL, Jensen FH, Knapp KJ, Robbins J, Tackaberry JE, Weinrich M, Friedlaender AS, Wiley DN, Parks SE. Caller identification and characterization of individual humpback whale acoustic behaviour. ROYAL SOCIETY OPEN SCIENCE 2024; 11:231608. [PMID: 38481982 PMCID: PMC10933536 DOI: 10.1098/rsos.231608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/24/2023] [Revised: 01/26/2024] [Accepted: 01/29/2024] [Indexed: 04/26/2024]
Abstract
Acoustic recording tags provide fine-scale data linking acoustic signalling with individual behaviour; however, when an animal is in a group, it is challenging to tease apart calls of conspecifics and identify which individuals produce each call. This, in turn, prohibits a robust assessment of individual acoustic behaviour including call rates and silent periods, call bout production within and between individuals, and caller location. To overcome this challenge, we simultaneously instrumented small groups of humpback whales on a western North Atlantic feeding ground with sound and movement recording tags. This approach enabled a comparison of the relative amplitude of each call across individuals to infer caller identity for 97% of calls. We recorded variable call rates across individuals (mean = 23 calls/h) and groups (mean = 55 calls/h). Calls were produced throughout dives, and most calls were produced in bouts with short inter-call intervals of 2.2 s. Most calls received a likely response from a conspecific within 100 s. This caller identification (ID) method facilitates studying both individual- and group-level acoustic behaviour, yielding novel results about the nature of sequence production and vocal exchanges in humpback whale social calls. Future studies can expand on these caller ID methods for understanding intra-group communication across taxa.
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Affiliation(s)
- Julia M Zeh
- Department of Biology, Syracuse University,107 College Place, Syracuse, NY 13244, USA
| | - Valeria Perez-Marrufo
- Department of Biology, Syracuse University,107 College Place, Syracuse, NY 13244, USA
| | - Dana L Adcock
- Department of Biology, Syracuse University,107 College Place, Syracuse, NY 13244, USA
| | - Frants H Jensen
- Department of Biology, Syracuse University,107 College Place, Syracuse, NY 13244, USA
- Department of Ecoscience, Aarhus University, Frederiksborgvej 399, Roskilde, Denmark
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Kaitlyn J Knapp
- Department of Biology, Syracuse University,107 College Place, Syracuse, NY 13244, USA
| | | | | | - Mason Weinrich
- Center for Coastal Studies, Provincetown, MA, USA
- Whale Center of New England, Gloucester, MA, USA
| | - Ari S Friedlaender
- Ocean Sciences & Institute of Marine Sciences, University of California Santa Cruz, Santa Cruz, CA, USA
| | - David N Wiley
- Stellwagen Bank National Marine Sanctuary, Scituate, MA, USA
| | - Susan E Parks
- Department of Biology, Syracuse University,107 College Place, Syracuse, NY 13244, USA
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5
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Jacobs ER, Gero S, Malinka CE, Tønnesen PH, Beedholm K, DeRuiter SL, Madsen PT. The active space of sperm whale codas: inter-click information for intra-unit communication. J Exp Biol 2024; 227:jeb246442. [PMID: 38264868 DOI: 10.1242/jeb.246442] [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: 07/19/2023] [Accepted: 01/16/2024] [Indexed: 01/25/2024]
Abstract
Sperm whales (Physeter macrocephalus) are social mega-predators who form stable matrilineal units that often associate within a larger vocal clan. Clan membership is defined by sharing a repertoire of coda types consisting of specific temporal spacings of multi-pulsed clicks. It has been hypothesized that codas communicate membership across socially segregated sympatric clans, but others propose that codas are primarily used for behavioral coordination and social cohesion within a closely spaced social unit. Here, we test these hypotheses by combining measures of ambient noise levels and coda click source levels with models of sound propagation to estimate the active space of coda communication. Coda clicks were localized off the island of Dominica with a four- or five-element 80 m vertical hydrophone array, allowing us to calculate the median RMS source levels of 1598 clicks from 444 codas to be 161 dB re. 1 μPa (IQR 153-167), placing codas among the most powerful communication sounds in toothed whales. However, together with measured ambient noise levels, these source levels lead to a median active space of coda communication of ∼4 km, reflecting the maximum footprint of a single foraging sperm whale unit. We conclude that while sperm whale codas may contain information about clan affiliation, their moderate active space shows that codas are not used for long range acoustic communication between units and clans, but likely serve to mediate social cohesion and behavioral transitions in intra-unit communication.
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Affiliation(s)
- Ellen R Jacobs
- Zoophysiology, Department of Biology, Aarhus University, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
- Department of Biology, Georgetown University, 3700 O St NW, Washington, DC 20057, USA
| | - Shane Gero
- Zoophysiology, Department of Biology, Aarhus University, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
- Department of Biology, Carleton University, 1125 Colonel By Dr, Ottawa, ON, Canada K1S 5B6
| | - Chloe E Malinka
- Zoophysiology, Department of Biology, Aarhus University, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
- SMRU Consulting, Scottish Oceans Institute, East Sands, University of St Andrews, KY16 8LB, UK
| | - Pernille H Tønnesen
- Zoophysiology, Department of Biology, Aarhus University, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
| | - Kristian Beedholm
- Zoophysiology, Department of Biology, Aarhus University, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
| | - Stacy L DeRuiter
- Department of Mathematics and Statistics, Calvin University, 3201 Burton St SE, Grand Rapids, MI 49546, USA
| | - Peter T Madsen
- Zoophysiology, Department of Biology, Aarhus University, C. F. Møllers Allé 3, DK-8000 Aarhus C, Denmark
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6
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Macklin GF, Moors-Murphy HB, Leonard ML. Characteristics and spatiotemporal variation of sei whale (Balaenoptera borealis) downsweeps recorded in Atlantic Canada. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2024; 155:145-155. [PMID: 38180155 DOI: 10.1121/10.0024213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 12/06/2023] [Indexed: 01/06/2024]
Abstract
The call characteristics and vocal behaviour of sei whales (Balaenoptera borealis) off eastern Canada, including potential spatiotemporal variation, is poorly understood. Such information can improve the performance of automated detector-classifiers, enhancing the accuracy and efficiency of identifying sei whales in large acoustic datasets. Ultimately, these data can be used to understand the occurrence, distribution, and population structure of sei whales in Atlantic Canada. We measured sei whale downsweep characteristics recorded from six locations off Nova Scotia (NS) and Newfoundland and Labrador (NFLD), Canada over a two-year period (2015-2017), and examined variation between call subtypes (singlets, doublets, triplets+), and seasons (Spring, Summer, Fall, Winter). We found that downsweeps had a mean duration of 1.58 s, sweeping from 75.66 to 34.22 Hz, with a peak frequency of 43.89 Hz and an intra-call interval of 2.22 s. Most call characteristics did not vary between location, subtype, or season; however, significantly longer downsweeps occurred off NS, within doublet calls, and in fall months. We also found that NFLD had a higher proportion of doublets (70%) than NS (52%). This variation may be evidence of acoustically diverging sei whale populations, as well as useful for improving detector-classifiers of sei whales in the region.
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Affiliation(s)
- Gabrielle F Macklin
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia B2Y 4A2, Canada
- Department of Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Hilary B Moors-Murphy
- Fisheries and Oceans Canada, Bedford Institute of Oceanography, Dartmouth, Nova Scotia B2Y 4A2, Canada
| | - Marty L Leonard
- Department of Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
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7
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Lamoni L, Garland EC, Allen JA, Coxon J, Noad MJ, Rendell L. Variability in humpback whale songs reveals how individuals can be distinctive when sharing a complex vocal display. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2023; 153:2238. [PMID: 37092914 DOI: 10.1121/10.0017602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Accepted: 02/25/2023] [Indexed: 05/03/2023]
Abstract
Individually distinctive acoustic signals in animal vocal communication are taxonomically widespread, however, the investigation of these signal types in marine mammals has focused only on a few species. Humpback whale songs are a stereotyped, hierarchically structured vocal display performed by males, and hence thought to be sexually selected. Within a population, whales conform to a common version of the song despite the song constantly evolving. While humpback songs have been studied extensively at the population level, individual level variation has been rarely described, with inconclusive results. Here, we quantified inter- and intra-individual variability at different levels in the song hierarchy using songs from 25 singers across two song types from the eastern Australian population song of 2002 (12 singers), and the revolutionary song introduced in 2003 (13 singers). Inter-individual variability was found heterogeneously across all hierarchical levels of the song structure. In addition, distinct and individually specific patterns of song production were consistently recorded across song levels, with clear structural differences between the two song types. These results suggest that within the constraints of song conformity, males can produce individually distinctive patterns that could function as an advertisement to females to convey individual qualities.
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Affiliation(s)
- Luca Lamoni
- Centre for Social Learning and Cognitive Evolution/Sea Mammal Research Unit, School of Biology, University of St. Andrews, St. Andrews KY16 9TH, United Kingdom
| | - Ellen C Garland
- Centre for Social Learning and Cognitive Evolution/Sea Mammal Research Unit, School of Biology, University of St. Andrews, St. Andrews KY16 9TH, United Kingdom
| | - Jenny A Allen
- Cetacean Ecology and Acoustics Laboratories, School of Veterinary Science, The University of Queensland, Gatton, Queensland 4343, Australia
| | - Jennifer Coxon
- Centre for Social Learning and Cognitive Evolution/Sea Mammal Research Unit, School of Biology, University of St. Andrews, St. Andrews KY16 9TH, United Kingdom
| | - Michael J Noad
- Cetacean Ecology and Acoustics Laboratories, School of Veterinary Science, The University of Queensland, Gatton, Queensland 4343, Australia
| | - Luke Rendell
- Centre for Social Learning and Cognitive Evolution/Sea Mammal Research Unit, School of Biology, University of St. Andrews, St. Andrews KY16 9TH, United Kingdom
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8
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Panova E, Agafonov A. Possible occurrence of contact calls in all‐male groups of free‐ranging beluga whales. J Zool (1987) 2023. [DOI: 10.1111/jzo.13054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Affiliation(s)
- E. Panova
- Shirshov Institute of Oceanology Russian Academy of Sciences Moscow Russia
| | - A. Agafonov
- Shirshov Institute of Oceanology Russian Academy of Sciences Moscow Russia
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9
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Zamorano-Abramson J, Michon M, Hernández-Lloreda MV, Aboitiz F. Multimodal imitative learning and synchrony in cetaceans: A model for speech and singing evolution. Front Psychol 2023; 14:1061381. [PMID: 37138983 PMCID: PMC10150787 DOI: 10.3389/fpsyg.2023.1061381] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 02/13/2023] [Indexed: 05/05/2023] Open
Abstract
Multimodal imitation of actions, gestures and vocal production is a hallmark of the evolution of human communication, as both, vocal learning and visual-gestural imitation, were crucial factors that facilitated the evolution of speech and singing. Comparative evidence has revealed that humans are an odd case in this respect, as the case for multimodal imitation is barely documented in non-human animals. While there is evidence of vocal learning in birds and in mammals like bats, elephants and marine mammals, evidence in both domains, vocal and gestural, exists for two Psittacine birds (budgerigars and grey parrots) and cetaceans only. Moreover, it draws attention to the apparent absence of vocal imitation (with just a few cases reported for vocal fold control in an orangutan and a gorilla and a prolonged development of vocal plasticity in marmosets) and even for imitation of intransitive actions (not object related) in monkeys and apes in the wild. Even after training, the evidence for productive or "true imitation" (copy of a novel behavior, i.e., not pre-existent in the observer's behavioral repertoire) in both domains is scarce. Here we review the evidence of multimodal imitation in cetaceans, one of the few living mammalian species that have been reported to display multimodal imitative learning besides humans, and their role in sociality, communication and group cultures. We propose that cetacean multimodal imitation was acquired in parallel with the evolution and development of behavioral synchrony and multimodal organization of sensorimotor information, supporting volitional motor control of their vocal system and audio-echoic-visual voices, body posture and movement integration.
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Affiliation(s)
- José Zamorano-Abramson
- Centro de Investigación en Complejidad Social, Facultad de Gobierno, Universidad del Desarrollo, Santiago, Chile
- Grupo UCM de Psicobiología Social, Evolutiva y Comparada, Universidad Complutense de Madrid, Madrid, Spain
- *Correspondence: José Zamorano-Abramson,
| | - Maëva Michon
- Centro de Estudios en Neurociencia Humana y Neuropsicología, Facultad de Psicología, Universidad Diego Portales, Santiago, Chile
- Laboratory for Cognitive and Evolutionary Neuroscience, Department of Psychiatry, Faculty of Medicine, Interdisciplinary Center for Neuroscience, Pontificia Universidad Católica de, Santiago, Chile
- Maëva Michon,
| | - Ma Victoria Hernández-Lloreda
- Grupo UCM de Psicobiología Social, Evolutiva y Comparada, Universidad Complutense de Madrid, Madrid, Spain
- Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Facultad de Psicología, Campus de Somosaguas, Universidad Complutense de Madrid, Madrid, Spain
| | - Francisco Aboitiz
- Laboratory for Cognitive and Evolutionary Neuroscience, Department of Psychiatry, Faculty of Medicine, Interdisciplinary Center for Neuroscience, Pontificia Universidad Católica de, Santiago, Chile
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10
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Michaud F, Sueur J, Le Cesne M, Haupert S. Unsupervised classification to improve the quality of a bird song recording dataset. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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11
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Evidence from sperm whale clans of symbolic marking in non-human cultures. Proc Natl Acad Sci U S A 2022; 119:e2201692119. [PMID: 36074817 PMCID: PMC9478646 DOI: 10.1073/pnas.2201692119] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Culture, a pillar of the remarkable ecological success of humans, is increasingly recognized as a powerful force structuring nonhuman animal populations. A key gap between these two types of culture is quantitative evidence of symbolic markers-seemingly arbitrary traits that function as reliable indicators of cultural group membership to conspecifics. Using acoustic data collected from 23 Pacific Ocean locations, we provide quantitative evidence that certain sperm whale acoustic signals exhibit spatial patterns consistent with a symbolic marker function. Culture segments sperm whale populations into behaviorally distinct clans, which are defined based on dialects of stereotyped click patterns (codas). We classified 23,429 codas into types using contaminated mixture models and hierarchically clustered coda repertoires into seven clans based on similarities in coda usage; then we evaluated whether coda usage varied with geographic distance within clans or with spatial overlap between clans. Similarities in within-clan usage of both "identity codas" (coda types diagnostic of clan identity) and "nonidentity codas" (coda types used by multiple clans) decrease as space between repertoire recording locations increases. However, between-clan similarity in identity, but not nonidentity, coda usage decreases as clan spatial overlap increases. This matches expectations if sympatry is related to a measurable pressure to diversify to make cultural divisions sharper, thereby providing evidence that identity codas function as symbolic markers of clan identity. Our study provides quantitative evidence of arbitrary traits, resembling human ethnic markers, conveying cultural identity outside of humans, and highlights remarkable similarities in the distributions of human ethnolinguistic groups and sperm whale clans.
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12
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Selection levels on vocal individuality: strategic use or byproduct. Curr Opin Behav Sci 2022. [DOI: 10.1016/j.cobeha.2022.101140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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13
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Andreas J, Beguš G, Bronstein MM, Diamant R, Delaney D, Gero S, Goldwasser S, Gruber DF, de Haas S, Malkin P, Pavlov N, Payne R, Petri G, Rus D, Sharma P, Tchernov D, Tønnesen P, Torralba A, Vogt D, Wood RJ. Toward understanding the communication in sperm whales. iScience 2022; 25:104393. [PMID: 35663036 PMCID: PMC9160774 DOI: 10.1016/j.isci.2022.104393] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
Machine learning has been advancing dramatically over the past decade. Most strides are human-based applications due to the availability of large-scale datasets; however, opportunities are ripe to apply this technology to more deeply understand non-human communication. We detail a scientific roadmap for advancing the understanding of communication of whales that can be built further upon as a template to decipher other forms of animal and non-human communication. Sperm whales, with their highly developed neuroanatomical features, cognitive abilities, social structures, and discrete click-based encoding make for an excellent model for advanced tools that can be applied to other animals in the future. We outline the key elements required for the collection and processing of massive datasets, detecting basic communication units and language-like higher-level structures, and validating models through interactive playback experiments. The technological capabilities developed by such an undertaking hold potential for cross-applications in broader communities investigating non-human communication and behavioral research.
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Affiliation(s)
- Jacob Andreas
- MIT CSAIL, Cambridge, MA, USA
- Project CETI, New York, NY, USA
| | - Gašper Beguš
- Department of Linguistics, University of California, Berkeley, CA, USA
- Project CETI, New York, NY, USA
| | - Michael M. Bronstein
- Department of Computer Science, University of Oxford, Oxford, UK
- IDSIA, University of Lugano, Lugano, Switzerland
- Twitter, London, UK
- Project CETI, New York, NY, USA
| | - Roee Diamant
- Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
- Project CETI, New York, NY, USA
| | - Denley Delaney
- Exploration Technology Lab, National Geographic Society, Washington DC, USA
- Project CETI, New York, NY, USA
| | - Shane Gero
- Dominica Sperm Whale Project, Roseau, Commonwealth of Dominica
- Department of Biology, Carleton University, Ottawa, ON, Canada
- Project CETI, New York, NY, USA
| | - Shafi Goldwasser
- Simons Institute for the Theory of Computing, University of California, Berkeley, CA, USA
| | - David F. Gruber
- Department of Natural Sciences, Baruch College and The Graduate Center, PhD Program in Biology, City University of New York, New York, NY, USA
- Project CETI, New York, NY, USA
| | - Sarah de Haas
- Google Research, Mountain View, CA USA
- Project CETI, New York, NY, USA
| | - Peter Malkin
- Google Research, Mountain View, CA USA
- Project CETI, New York, NY, USA
| | | | | | - Giovanni Petri
- ISI Foundation, Turin, Italy
- Project CETI, New York, NY, USA
| | - Daniela Rus
- MIT CSAIL, Cambridge, MA, USA
- Project CETI, New York, NY, USA
| | | | - Dan Tchernov
- Leon H. Charney School of Marine Sciences, University of Haifa, Haifa, Israel
- Project CETI, New York, NY, USA
| | - Pernille Tønnesen
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, Aarhus, Denmark
- Project CETI, New York, NY, USA
| | | | - Daniel Vogt
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Project CETI, New York, NY, USA
| | - Robert J. Wood
- School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA
- Project CETI, New York, NY, USA
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14
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Vachon F, Hersh TA, Rendell L, Gero S, Whitehead H. Ocean nomads or island specialists? Culturally driven habitat partitioning contrasts in scale between geographically isolated sperm whale populations. ROYAL SOCIETY OPEN SCIENCE 2022; 9:211737. [PMID: 35619996 PMCID: PMC9114939 DOI: 10.1098/rsos.211737] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 04/14/2022] [Indexed: 05/03/2023]
Abstract
The sperm whale (Physeter macrocephalus) is a deep-diving cetacean with a global distribution and a multi-leveled, culturally segregated, social structure. While sperm whales have previously been described as 'ocean nomads', this might not be universal. We conducted surveys of sperm whales along the Lesser Antilles to document the acoustic repertoires, movements and distributions of Eastern Caribbean (EC) sperm whale cultural groups (called vocal clans). In addition to documenting a potential third vocal clan in the EC, we found strong evidence of fine-scale habitat partitioning between vocal clans with scales of horizontal movements an order of magnitude smaller than from comparable studies on Eastern Tropical Pacific sperm whales. These results suggest that sperm whales can display cultural ecological specialization and habitat partitioning on flexible spatial scales according to local conditions and broadens our perception of the ecological flexibility of the species. This study highlights the importance of incorporating multiple temporal and spatial scales to understand the impact of culture on ecological adaptability, as well as the dangers of extrapolating results across geographical areas and cultural groups.
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Affiliation(s)
- Felicia Vachon
- Department of Biology, Dalhousie University, Halifax, Canada
| | - Taylor A. Hersh
- Department of Biology, Dalhousie University, Halifax, Canada
- Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands
| | - Luke Rendell
- Sea Mammal Research Unit, University of St Andrews, School of Biology, St Andrews, UK
| | - Shane Gero
- Department of Biology, Dalhousie University, Halifax, Canada
- Sea Mammal Research Unit, University of St Andrews, School of Biology, St Andrews, UK
- Department of Biology, Carleton University, Ottawa, Canada
- Department of Zoophysiology, Aarhus University, Aarhus, Denmark
| | - Hal Whitehead
- Department of Biology, Dalhousie University, Halifax, Canada
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15
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Pace DS, Tumino C, Silvestri M, Giacomini G, Pedrazzi G, Pavan G, Papale E, Ceraulo M, Buscaino G, Ardizzone G. Bray-Call Sequences in the Mediterranean Common Bottlenose Dolphin ( Tursiops truncatus) Acoustic Repertoire. BIOLOGY 2022; 11:biology11030367. [PMID: 35336741 PMCID: PMC8945472 DOI: 10.3390/biology11030367] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 02/14/2022] [Accepted: 02/23/2022] [Indexed: 11/16/2022]
Abstract
Simple Summary In the acoustic repertoire of common bottlenose dolphins (Tursiops truncatus), Gulps, Grunts, and Squeaks are part of a group of vocalizations called “bray-call” for which little has been previously studied. The name comes from the alternating structure characteristic of a donkey’s bray. Sounds can be of different types at low frequencies and audible to the human hear—of short duration, produced in sequence. The function of these sequences is not clarified yet, and it is not known if they are part of the vocal “catalog” of all the different populations of common bottlenose dolphin at global level. What is certain is that bray-calls are present in two geographical areas of the Mediterranean and that the “Capitoline” individuals (Rome, Tyrrhenian Sea, Italy) emit them with greater frequency and variety than the Sicilian ones (Mazara del Vallo, Sicilian Channel, Italy). A number of 13 different types of sequences have been identified, and only 2 of them are shared between the study areas. For the first time this study identifies variants of the main bray-call elements, highlights the structural complexity of these vocalizations, and suggests addressing future research on the context of emissions and the possible function(s) of such acoustic arrangements. Abstract Acoustic sequences are commonly observed in many animal taxa. The vast vocal repertoire of common bottlenose dolphins (Tursiops truncatus) also includes sequences of multi-unit rhythmic signals called bray-call which are still poorly documented, both functionally and geographically. This study aimed to (1) describe, classify, and characterize series of bray-call recorded in two sites of the Mediterranean basin (Rome—Tyrrhenian Sea and Mazara del Vallo—Strait of Sicily) and (2) investigate for the existence of possible geographic differences. The acoustic analysis identified 13 different sequence types, only two detected in both study areas. The Sørensen–Dice index revealed a low degree of similarity between the sequence repertoire of the two common bottlenose dolphin sub-populations, with the Tyrrhenian being more diversified and complex than the Sicilian one. The acoustic parameters also showed variability between the study area. Different variants of the main acoustic elements composing the bray-call sequences were detected in the Tyrrhenian Sea only. The Markov-chain model demonstrated that the transition probability between acoustic elements is not uniform, with specific combinations of elements having a higher probability of occurrence. These new findings on common bottlenose dolphin bray-call sequences highlight the structural complexity of these vocalizations and suggest addressing future research on the context of emissions and the possible function(s) of such acoustic arrangements.
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Affiliation(s)
- Daniela Silvia Pace
- Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy; (C.T.); (G.G.); (G.P.); (G.A.)
- Correspondence: ; Tel.: +39-(0)6-4991-4763
| | - Carla Tumino
- Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy; (C.T.); (G.G.); (G.P.); (G.A.)
| | - Margherita Silvestri
- Department of Environmental and Evolutionary Sciences, University Austral of Chile, Valdivia 5090000, Chile;
| | - Giancarlo Giacomini
- Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy; (C.T.); (G.G.); (G.P.); (G.A.)
| | - Giulia Pedrazzi
- Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy; (C.T.); (G.G.); (G.P.); (G.A.)
| | - Gianni Pavan
- Department of Earth and Environmental Sciences, University of Pavia, 27100 Pavia, Italy;
| | - Elena Papale
- Consiglio Nazionale delle Ricerche-Istituto per lo Studio degli Impatti Antropici e Sostenibilità, Campobello di Mazara, 91021 Trapani, Italy; (E.P.); (M.C.); (G.B.)
- Department of Life Sciences and Systems Biology, University of Torino, 10123 Torino, Italy
| | - Maria Ceraulo
- Consiglio Nazionale delle Ricerche-Istituto per lo Studio degli Impatti Antropici e Sostenibilità, Campobello di Mazara, 91021 Trapani, Italy; (E.P.); (M.C.); (G.B.)
| | - Giuseppa Buscaino
- Consiglio Nazionale delle Ricerche-Istituto per lo Studio degli Impatti Antropici e Sostenibilità, Campobello di Mazara, 91021 Trapani, Italy; (E.P.); (M.C.); (G.B.)
| | - Giandomenico Ardizzone
- Department of Environmental Biology, Sapienza University of Rome, 00185 Rome, Italy; (C.T.); (G.G.); (G.P.); (G.A.)
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16
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Soldevilla MS, Debich AJ, Garrison LP, Hildebrand JA, Wiggins SM. Rice’s whales in the northwestern Gulf of Mexico: call variation and occurrence beyond the known core habitat. ENDANGER SPECIES RES 2022. [DOI: 10.3354/esr01196] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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17
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Barkley YM, Nosal EM, Oleson EM. Model-based localization of deep-diving cetaceans using towed line array acoustic data. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 150:1120. [PMID: 34470263 DOI: 10.1121/10.0005847] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 07/19/2021] [Indexed: 06/13/2023]
Abstract
Passive acoustic monitoring using a towed line array of hydrophones is a standard method for localizing cetaceans during line-transect cetacean abundance surveys. Perpendicular distances estimated between localized whales and the trackline are essential for abundance estimation using acoustic data. Uncertainties in the acoustic data from hydrophone movement, sound propagation effects, errors in the time of arrival differences, and whale depth are not accounted for by most two-dimensional localization methods. Consequently, location and distance estimates for deep-diving cetaceans may be biased, creating uncertainty in abundance estimates. Here, a model-based localization approach is applied to towed line array acoustic data that incorporates sound propagation effects, accounts for sources of error, and localizes in three dimensions. The whale's true distance, ship trajectory, and whale movement greatly affected localization results in simulations. The localization method was applied to real acoustic data from two separate sperm whales, resulting in three-dimensional distance and depth estimates with position bounds for each whale. By incorporating sources of error, this three-dimensional model-based approach provides a method to address and integrate the inherent uncertainties in towed array acoustic data for more robust localization.
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Affiliation(s)
- Yvonne M Barkley
- Hawai'i Institute of Marine Biology, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Kāne'ohe, Hawaii 96822, USA
| | - Eva-Marie Nosal
- Ocean Resources and Engineering, School of Ocean and Earth Science and Technology, University of Hawai'i at Mānoa, Honolulu, Hawaii 96822, USA
| | - Erin M Oleson
- Protected Species Division, Pacific Islands Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, Honolulu, Hawaii 96818, USA
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18
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Luís AR, May-Collado LJ, Rako-Gospić N, Gridley T, Papale E, Azevedo A, Silva MA, Buscaino G, Herzing D, dos Santos ME. Vocal universals and geographic variations in the acoustic repertoire of the common bottlenose dolphin. Sci Rep 2021; 11:11847. [PMID: 34088923 PMCID: PMC8178411 DOI: 10.1038/s41598-021-90710-9] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 04/29/2021] [Indexed: 02/04/2023] Open
Abstract
Acoustical geographic variation is common in widely distributed species and it is already described for several taxa, at various scales. In cetaceans, intraspecific variation in acoustic repertoires has been linked to ecological factors, geographical barriers, and social processes. For the common bottlenose dolphin (Tursiops truncatus), studies on acoustic variability are scarce, focus on a single signal type-whistles and on the influence of environmental variables. Here, we analyze the acoustic emissions of nine bottlenose dolphin populations across the Atlantic Ocean and the Mediterranean Sea, and identify common signal types and acoustic variants to assess repertoires' (dis)similarity. Overall, these dolphins present a rich acoustic repertoire, with 24 distinct signal sub-types including: whistles, burst-pulsed sounds, brays and bangs. Acoustic divergence was observed only in social signals, suggesting the relevance of cultural transmission in geographic variation. The repertoire dissimilarity values were remarkably low (from 0.08 to 0.4) and do not reflect the geographic distances among populations. Our findings suggest that acoustic ecology may play an important role in the occurrence of intraspecific variability, as proposed by the 'environmental adaptation hypothesis'. Further work may clarify the boundaries between neighboring populations, and shed light into vocal learning and cultural transmission in bottlenose dolphin societies.
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Affiliation(s)
- A. R. Luís
- grid.410954.d0000 0001 2237 5901MARE - Marine and Environmental Sciences Centre, ISPA - Instituto Universitário, Rua Jardim do Tabaco, 34, 1149-041 Lisboa, Portugal ,Projecto Delfim - Centro Português de Estudo dos Mamíferos Marinhos, Rua Jardim do Tabaco, 34, 1149-041 Lisboa, Portugal
| | - L. J. May-Collado
- grid.59062.380000 0004 1936 7689Department of Biology, University of Vermont, Burlington, VT 05403 USA ,grid.412889.e0000 0004 1937 0706Centro de Investigacion en Ciencias del Mar y Limnologia, Universidad de Costa Rica, San Jose, Costa Rica
| | - N. Rako-Gospić
- Blue World Institute of Marine Research and Conservation, Kaštel 24, 51551 Veli Lošinj, Croatia
| | - T. Gridley
- grid.7836.a0000 0004 1937 1151Centre for Statistics in Ecology, Environment and Conservation, Department of Statistical Sciences, University of Cape Town, C/O Sea Search Research and Conservation NPC, Cape Town, South Africa
| | - E. Papale
- grid.5326.20000 0001 1940 4177Institute for the Study of Antropogenic Impacts and Sustainability in the Marine Environment, National Research Council, Capo Granitola, Via del Mare 3, 91021 Torretta Granitola (TP), Italy ,grid.7605.40000 0001 2336 6580Department of Life Sciences and Systems Biology, University of Torino, Via Accademia Albertina 13, 10123 Torino, Italy
| | - A. Azevedo
- grid.412211.5Laboratório de Mamíferos Aquáticos e Bioindicadores Profª Izabel Gurgel (MAQUA), Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil
| | - M. A. Silva
- grid.7338.f0000 0001 2096 9474OKEANOS & IMAR – Instituto do Mar, Universidade dos Açores, 9901-862 Horta, Portugal
| | - G. Buscaino
- grid.5326.20000 0001 1940 4177Institute for the Study of Antropogenic Impacts and Sustainability in the Marine Environment, National Research Council, Capo Granitola, Via del Mare 3, 91021 Torretta Granitola (TP), Italy
| | - D. Herzing
- Wild Dolphin Project, P.O. Box 8436, Jupiter, FL 33468 USA ,grid.255951.f0000 0004 0635 0263Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL 33431 USA
| | - M. E. dos Santos
- grid.410954.d0000 0001 2237 5901MARE - Marine and Environmental Sciences Centre, ISPA - Instituto Universitário, Rua Jardim do Tabaco, 34, 1149-041 Lisboa, Portugal ,Projecto Delfim - Centro Português de Estudo dos Mamíferos Marinhos, Rua Jardim do Tabaco, 34, 1149-041 Lisboa, Portugal
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19
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Hare AJ, Newman AE, Dantzer B, Lane JE, Boutin S, Coltman DW, McAdam AG. An independent experiment does not support stress-mediated kin discrimination through red squirrel vocalizations. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.04.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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20
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Woodward SF, Reiss D, Magnasco MO. Learning to localize sounds in a highly reverberant environment: Machine-learning tracking of dolphin whistle-like sounds in a pool. PLoS One 2020; 15:e0235155. [PMID: 32584861 PMCID: PMC7316258 DOI: 10.1371/journal.pone.0235155] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 06/09/2020] [Indexed: 11/19/2022] Open
Abstract
Tracking the origin of propagating wave signals in an environment with complex reflective surfaces is, in its full generality, a nearly intractable problem which has engendered multiple domain-specific literatures. We posit that, if the environment and sensor geometries are fixed, machine learning algorithms can "learn" the acoustical geometry of the environment and accurately track signal origin. In this paper, we propose the first machine-learning-based approach to identifying the source locations of semi-stationary, tonal, dolphin-whistle-like sounds in a highly reverberant space, specifically a half-cylindrical dolphin pool. Our algorithm works by supplying a learning network with an overabundance of location "clues", which are then selected under supervised training for their ability to discriminate source location in this particular environment. More specifically, we deliver estimated time-difference-of-arrivals (TDOA's) and normalized cross-correlation values computed from pairs of hydrophone signals to a random forest model for high-feature-volume classification and feature selection, and subsequently deliver the selected features into linear discriminant analysis, linear and quadratic Support Vector Machine (SVM), and Gaussian process models. Based on data from 14 sound source locations and 16 hydrophones, our classification models yielded perfect accuracy at predicting novel sound source locations. Our regression models yielded better accuracy than the established Steered-Response Power (SRP) method when all training data were used, and comparable accuracy along the pool surface when deprived of training data at testing sites; our methods additionally boast improved computation time and the potential for superior localization accuracy in all dimensions with more training data. Because of the generality of our method we argue it may be useful in a much wider variety of contexts.
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Affiliation(s)
- Sean F. Woodward
- Laboratory of Integrative Neuroscience, Center for Studies in Physics and Biology, The Rockefeller University, New York, NY, United States of America
- * E-mail:
| | - Diana Reiss
- Department of Psychology, Hunter College, City University of New York, New York, NY, United States of America
| | - Marcelo O. Magnasco
- Laboratory of Integrative Neuroscience, Center for Studies in Physics and Biology, The Rockefeller University, New York, NY, United States of America
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21
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Fisher DN, Pruitt JN. Insights from the study of complex systems for the ecology and evolution of animal populations. Curr Zool 2020; 66:1-14. [PMID: 32467699 PMCID: PMC7245006 DOI: 10.1093/cz/zoz016] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 04/02/2019] [Indexed: 12/01/2022] Open
Abstract
Populations of animals comprise many individuals, interacting in multiple contexts, and displaying heterogeneous behaviors. The interactions among individuals can often create population dynamics that are fundamentally deterministic yet display unpredictable dynamics. Animal populations can, therefore, be thought of as complex systems. Complex systems display properties such as nonlinearity and uncertainty and show emergent properties that cannot be explained by a simple sum of the interacting components. Any system where entities compete, cooperate, or interfere with one another may possess such qualities, making animal populations similar on many levels to complex systems. Some fields are already embracing elements of complexity to help understand the dynamics of animal populations, but a wider application of complexity science in ecology and evolution has not occurred. We review here how approaches from complexity science could be applied to the study of the interactions and behavior of individuals within animal populations and highlight how this way of thinking can enhance our understanding of population dynamics in animals. We focus on 8 key characteristics of complex systems: hierarchy, heterogeneity, self-organization, openness, adaptation, memory, nonlinearity, and uncertainty. For each topic we discuss how concepts from complexity theory are applicable in animal populations and emphasize the unique insights they provide. We finish by outlining outstanding questions or predictions to be evaluated using behavioral and ecological data. Our goal throughout this article is to familiarize animal ecologists with the basics of each of these concepts and highlight the new perspectives that they could bring to variety of subfields.
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Affiliation(s)
- David N Fisher
- Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, ON, Canada
| | - Jonathan N Pruitt
- Department of Psychology, Neuroscience & Behaviour, McMaster University, Hamilton, ON, Canada
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22
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Grueter CC, Qi X, Zinner D, Bergman T, Li M, Xiang Z, Zhu P, Migliano AB, Miller A, Krützen M, Fischer J, Rubenstein DI, Vidya TNC, Li B, Cantor M, Swedell L. Multilevel Organisation of Animal Sociality. Trends Ecol Evol 2020; 35:834-847. [PMID: 32473744 DOI: 10.1016/j.tree.2020.05.003] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 05/01/2020] [Accepted: 05/06/2020] [Indexed: 12/16/2022]
Abstract
Multilevel societies (MLSs), stable nuclear social units within a larger collective encompassing multiple nested social levels, occur in several mammalian lineages. Their architectural complexity and size impose specific demands on their members requiring adaptive solutions in multiple domains. The functional significance of MLSs lies in their members being equipped to reap the benefits of multiple group sizes. Here, we propose a unifying terminology and operational definition of MLS. To identify new avenues for integrative research, we synthesise current literature on the selective pressures underlying the evolution of MLSs and their implications for cognition, intersexual conflict, and sexual selection. Mapping the drivers and consequences of MLS provides a reference point for the social evolution of many taxa, including our own species.
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Affiliation(s)
- Cyril C Grueter
- School of Human Sciences, The University of Western Australia, Perth, WA 6009, Australia; Centre for Evolutionary Biology, School of Biological Sciences, The University of Western Australia, Perth, WA 6009, Australia.
| | - Xiaoguang Qi
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, College of Life Sciences, Xi'an, 710069, China.
| | - Dietmar Zinner
- Cognitive Ethology Laboratory, German Primate Center (DPZ), Leibniz Institute for Primate Research, 37077 Göttingen, Germany; Leibniz ScienceCampus for Primate Cognition, 37077 Göttingen, Germany
| | - Thore Bergman
- Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA; Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Ming Li
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chaoyang District, Beijing 100101, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, 650223, China
| | - Zuofu Xiang
- College of Life Science and Technology, Central South University of Forestry and Technology, Changsha, Hunan 410004, China
| | - Pingfen Zhu
- CAS Key Laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chaoyang District, Beijing 100101, China
| | | | - Alex Miller
- School of Human Sciences, The University of Western Australia, Perth, WA 6009, Australia
| | - Michael Krützen
- Department of Anthropology, University of Zurich, 8057, Zürich, Switzerland
| | - Julia Fischer
- Cognitive Ethology Laboratory, German Primate Center (DPZ), Leibniz Institute for Primate Research, 37077 Göttingen, Germany; Department for Primate Cognition, Georg-August-University of Göttingen, 37077 Göttingen, Germany
| | - Daniel I Rubenstein
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA
| | - T N C Vidya
- Evolutionary and Organismal Biology Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bengaluru 560064, India
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation, Northwest University, College of Life Sciences, Xi'an, 710069, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, 650223, China
| | - Maurício Cantor
- Department for the Ecology of Animal Societies, Max Planck Institute of Animal Behavior, Konstanz, 78464, Germany; Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, 78464, Germany; Department of Biology, University of Konstanz, Konstanz, 78464, Germany; Departamento de Ecologia e Zoologia, Universidade Federal de Santa Catarina, Florianópolis, 88048-970, Brazil; Centro de Estudos do Mar, Universidade Federal do Paraná, Pontal do Paraná, 83255-000, Brazil; School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Johannesburg, 2000, South Africa
| | - Larissa Swedell
- Department of Anthropology, Queens College, City University of New York, Flushing, NY 11367-1597, USA; New York Consortium in Evolutionary Primatology, New York, NY 11367, USA; Anthropology, Biology and Psychology Programs, CUNY Graduate Center, 365 Fifth Avenue, New York, NY 10016, USA; Department of Archaeology, University of Cape Town, Rondebosch, 7701, Cape Town, South Africa
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23
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Walmsley SF, Rendell L, Hussey NE, Marcoux M. Vocal sequences in narwhals (Monodon monoceros). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2020; 147:1078. [PMID: 32113269 DOI: 10.1121/10.0000671] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Accepted: 01/13/2020] [Indexed: 06/10/2023]
Abstract
Sequences are indicative of signal complexity in vocal communication. While vocal sequences are well-described in birds and terrestrial mammals, the extent to which marine mammals use them is less well understood. This study documents the first known examples of sequence use in the narwhal (Monodon monoceros), a gregarious Arctic cetacean. Eight female narwhals were fitted with animal-borne recording devices, resulting in one of the largest datasets of narwhal acoustic behaviour to date. A combination of visual and quantitative classification procedures was used to test whether subjectively defined vocalization patterns were organized into sequences. Next, acoustic characteristics were analyzed to assess whether sequences could disclose group or individual identity. Finally, generalized linear models were used to investigate the behavioural context under which sequences were produced. Two types of sequences, consisting of "paired" patterns and "burst pulse series," were identified. Sequences of burst pulse series were typically produced in periods of high vocal activity, whereas the opposite was true for sequences of paired patterns, suggesting different functions for each. These findings extend the set of odontocetes which are known to use vocal sequences. Inquiry into vocal sequences in other understudied marine mammals may provide further insights into the evolution of vocal communication.
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Affiliation(s)
- Sam F Walmsley
- Sea Mammal Research Unit, School of Biology, University of St Andrews, Sir Harold Mitchell Building, St Andrews, KY16 9TH, Scotland
| | - Luke Rendell
- Sea Mammal Research Unit, School of Biology, University of St Andrews, Sir Harold Mitchell Building, St Andrews, KY16 9TH, Scotland
| | - Nigel E Hussey
- Integrative Biology, University of Windsor, 401 Sunset Avenue, Windsor, Ontario, N9B 3P4, Canada
| | - Marianne Marcoux
- Arctic Aquatic Research Division, Fisheries and Oceans Canada, Winnipeg, Manitoba, R3T 2N6, Canada
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24
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Melo-Santos G, Walmsley SF, Marmontel M, Oliveira-da-Costa M, Janik VM. Repeated downsweep vocalizations of the Araguaian river dolphin, Inia araguaiaensis. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2020; 147:748. [PMID: 32113279 DOI: 10.1121/10.0000624] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Accepted: 01/09/2020] [Indexed: 06/10/2023]
Abstract
Araguaian botos (Inia araguaiaensis) are known to produce pulsed as well as tonal sounds. This study documents the first evidence for repetitive sequences of downsweep whistles in botos that appear to be shared between individuals, and the context of their occurrence is investigated. Boat surveys were conducted along the Tocantins River located in the Eastern Amazon over a period of 42 days between 2012 and 2018. Eighty-two groups of Araguaian botos were observed, and 43 h of sound recordings were acquired. 632 downsweep whistles were recorded in 10 encounters. Four of these encounters contained downsweep bouts (21 bouts with ≥2 whistles) with short inter-call intervals (bout criterion 50 s) and up to 161 whistles. A statistical relationship was not found between downsweep occurrence and any of the contextual parameters that were investigated, including socializing, travelling, feeding, group size, presence of calves, and socio-sexual displays. The rarity of these signals makes them unlikely candidates for individual or group identification. It is more likely that they are associated with very specific contexts, such as nursing or mating, both of which were rarely observed in this study. Further studies are required to investigate context specificity and elucidate the function of these signals.
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Affiliation(s)
- Gabriel Melo-Santos
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St Andrews, East Sands, KY16 8LB, St Andrews, Scotland, United Kingdom
| | - Sam F Walmsley
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St Andrews, East Sands, KY16 8LB, St Andrews, Scotland, United Kingdom
| | - Miriam Marmontel
- Research Group on Amazonian Aquatic Mammals, Mamirauá Sustainable, Development Institute, Estrada do Bexiga No. 2584, Tefé, Brazil
| | | | - Vincent M Janik
- Sea Mammal Research Unit, Scottish Oceans Institute, School of Biology, University of St Andrews, East Sands, KY16 8LB, St Andrews, Scotland, United Kingdom
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Armansin NC, Stow AJ, Cantor M, Leu ST, Klarevas-Irby JA, Chariton AA, Farine DR. Social Barriers in Ecological Landscapes: The Social Resistance Hypothesis. Trends Ecol Evol 2020; 35:137-148. [DOI: 10.1016/j.tree.2019.10.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 09/27/2019] [Accepted: 10/01/2019] [Indexed: 10/25/2022]
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Deep Machine Learning Techniques for the Detection and Classification of Sperm Whale Bioacoustics. Sci Rep 2019; 9:12588. [PMID: 31467331 PMCID: PMC6715799 DOI: 10.1038/s41598-019-48909-4] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 08/15/2019] [Indexed: 11/08/2022] Open
Abstract
We implemented Machine Learning (ML) techniques to advance the study of sperm whale (Physeter macrocephalus) bioacoustics. This entailed employing Convolutional Neural Networks (CNNs) to construct an echolocation click detector designed to classify spectrograms generated from sperm whale acoustic data according to the presence or absence of a click. The click detector achieved 99.5% accuracy in classifying 650 spectrograms. The successful application of CNNs to clicks reveals the potential of future studies to train CNN-based architectures to extract finer-scale details from cetacean spectrograms. Long short-term memory and gated recurrent unit recurrent neural networks were trained to perform classification tasks, including (1) “coda type classification” where we obtained 97.5% accuracy in categorizing 23 coda types from a Dominica dataset containing 8,719 codas and 93.6% accuracy in categorizing 43 coda types from an Eastern Tropical Pacific (ETP) dataset with 16,995 codas; (2) “vocal clan classification” where we obtained 95.3% accuracy for two clan classes from Dominica and 93.1% for four ETP clan types; and (3) “individual whale identification” where we obtained 99.4% accuracy using two Dominica sperm whales. These results demonstrate the feasibility of applying ML to sperm whale bioacoustics and establish the validity of constructing neural networks to learn meaningful representations of whale vocalizations.
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Mishima Y, Morisaka T, Ishikawa M, Karasawa Y, Yoshida Y. Pulsed call sequences as contact calls in Pacific white-sided dolphins (Lagenorhynchus obliquidens). THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 146:409. [PMID: 31370601 DOI: 10.1121/1.5116692] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 06/25/2019] [Indexed: 06/10/2023]
Abstract
Pacific white-sided dolphins are a group-living species and appear to exchange "contact calls" to maintain group cohesion. The aim of this study was to find and characterize their contact calls. Calls were recorded from two females at Osaka Aquarium KAIYUKAN (OAK) and three females at Izu-Mito Sea Paradise (IMSP). Because they often produced pulsed calls consecutively, a "pulsed call sequence" was defined as three or more successive pulsed calls occurring within 325 ms, which was calculated using a bout analysis. The pulsed call sequences increased during separation periods and decreased during reunions and were used for vocal exchange, suggesting that the sequences are contact calls in Pacific white-sided dolphins. Most of the pulsed call sequences were classified into unique types; several stereotyped, repeated patterns were found. One sequence type was found at OAK and the two dolphins shared the type; they exchanged sequences with type matching. On the other hand, three sequence types were found in IMSP and the three dolphins shared all of the types; however, each dolphin preferentially used different types and frequently exchanged with their own favorite types but not with type matching. These results suggest that the sequence type may function as an individual and/or group identity.
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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
| | - Tadamichi Morisaka
- Cetacean Research Center, Graduate School of Bioresources, Mie University, 1577, Kurimamachiya-cho, Tsu-shi, Mie, 514-8507, Japan
| | - Megumi Ishikawa
- Osaka Aquarium KAIYUKAN, 1-1-10, Kaigandori, Minato-ku, Osaka-shi, Osaka, 552-0022, Japan
| | - Yuu Karasawa
- Izu-Mito Sea Paradise, 3-1, Nagahama, Uchiura, Numazu-shi, Shizuoka, 410-0295, Japan
| | - Yayoi Yoshida
- Department of Environmental and Societal Affairs, School of Marine Science and Technology, Tokai University, 3-20-1, Orido, Shimizu-ku, Shizuoka-shi, Shizuoka, 424-8610, Japan
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Martin MJ, Elwen SH, Kassanjee R, Gridley T. To buzz or burst-pulse? The functional role of Heaviside's dolphin, Cephalorhynchus heavisidii, rapidly pulsed signals. Anim Behav 2019. [DOI: 10.1016/j.anbehav.2019.01.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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Van Cise AM, Mahaffy SD, Baird RW, Mooney TA, Barlow J. Song of my people: dialect differences among sympatric social groups of short-finned pilot whales in Hawai’i. Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2596-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Beslin WAM, Whitehead H, Gero S. Automatic acoustic estimation of sperm whale size distributions achieved through machine recognition of on-axis clicks. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2018; 144:3485. [PMID: 30599680 DOI: 10.1121/1.5082291] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 11/14/2018] [Indexed: 06/09/2023]
Abstract
The waveforms of individual sperm whale clicks often appear as multiple pulses, which are the product of a single pulse reverberating throughout the spermaceti organ. Since there is a relationship between spermaceti organ size and total body size, it is possible to estimate a whale's length by measuring the inter-pulse intervals (IPIs) within its clicks. However, if a click is recorded off-axis, the IPI corresponding to spermaceti organ length is usually obscured. This paper presents an algorithm for automatically estimating the "true" IPIs of sperm whales in a recording by measuring them from on-axis clicks only. The routine works by classifying detected clicks with a support vector machine, assessing the stability of their IPIs, and then clustering the stable IPIs using Gaussian mixture models. Results show that the routine is very accurate in obtaining reliable IPIs, but has a high false negative rate. Nonetheless, since sperm whales click very frequently, it is possible to obtain useful IPI distributions with only a few minutes of recording. This algorithm makes it possible to estimate the body lengths of multiple sperm whales automatically with only one hydrophone. An implementation is available for download at http://whitelab.biology.dal.ca/CABLE/cable.htm.
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Affiliation(s)
- Wilfried A M Beslin
- Department of Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Hal Whitehead
- Department of Biology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Shane Gero
- Zoophysiology, Institute for Bioscience, Aarhus University, Aarhus, Denmark
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Konrad CM, Frasier TR, Rendell L, Whitehead H, Gero S. Kinship and association do not explain vocal repertoire variation among individual sperm whales or social units. Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.09.011] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Tønnesen P, Gero S, Ladegaard M, Johnson M, Madsen PT. First-year sperm whale calves echolocate and perform long, deep dives. Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2570-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Konrad CM, Gero S, Frasier T, Whitehead H. Kinship influences sperm whale social organization within, but generally not among, social units. ROYAL SOCIETY OPEN SCIENCE 2018; 5:180914. [PMID: 30225081 PMCID: PMC6124104 DOI: 10.1098/rsos.180914] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 08/06/2018] [Indexed: 05/14/2023]
Abstract
Sperm whales have a multi-level social structure based upon long-term, cooperative social units. What role kinship plays in structuring this society is poorly understood. We combined extensive association data (518 days, during 2005-2016) and genetic data (18 microsatellites and 346 bp mitochondrial DNA (mtDNA) control region sequences) for 65 individuals from 12 social units from the Eastern Caribbean to examine patterns of kinship and social behaviour. Social units were clearly matrilineally based, evidenced by greater relatedness within social units (mean r = 0.14) than between them (mean r = 0.00) and uniform mtDNA haplotypes within social units. Additionally, most individuals (82.5%) had a first-degree relative in their social unit, while we found no first-degree relatives between social units. Generally and within social units, individuals associated more with their closer relatives (matrix correlations: 0.18-0.25). However, excepting a highly related pair of social units that merged over the study period, associations between social units were not correlated with kinship (p > 0.1). These results are the first to robustly demonstrate kinship's contribution to social unit composition and association preferences, though they also reveal variability in association preferences that is unexplained by kinship. Comparisons with other matrilineal species highlight the range of possible matrilineal societies and how they can vary between and even within species.
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Affiliation(s)
- Christine M. Konrad
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, CanadaB3H 4J1
| | - Shane Gero
- Department of Zoophysiology, Institute for Bioscience, Aarhus University, C.F. Møllers Allé 3, Aarhus 8000, Denmark
| | - Timothy Frasier
- Department of Biology, Saint Mary's University, 923 Robie Street, Halifax, Nova Scotia, CanadaB3H 3C3
| | - Hal Whitehead
- Department of Biology, Dalhousie University, 1355 Oxford Street, Halifax, Nova Scotia, CanadaB3H 4J1
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Bøttcher A, Gero S, Beedholm K, Whitehead H, Madsen PT. Variability of the inter-pulse interval in sperm whale clicks with implications for size estimation and individual identification. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2018; 144:365. [PMID: 30075661 DOI: 10.1121/1.5047657] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Accepted: 07/05/2018] [Indexed: 06/08/2023]
Abstract
Sperm whales generate multi-pulsed clicks for echolocation and communication with an inter-pulse interval (IPI) determined by the size of their hypertrophied sound producing nose. The IPI has therefore been used to estimate body size and distinguish between individuals, and it has been hypothesized that conspecifics may use IPIs to recognize each other. However, the degree to which IPIs vary within individuals has not explicitly been tested, and therefore the inherent precision of this measure and its applicability for size estimation for researchers and sperm whales alike remain unknown. Here, the variability in IPI from both animal-borne Dtags and far-field recordings from echolocating and communicating sperm whales is quantified. Three different automatic methods (envelope, cepstrum, and cross-correlation) are tested and it is found that the envelope approach results in the least dispersion. Furthermore, it is shown that neither growth, depth, nor recording aspect fully explains the observed variability among clicks recorded from the same individual. It is proposed that dynamics in the soft structures of the nose are affecting IPIs, resulting in a variation of approximately 0.2 ms. Therefore, it is recommended that this variation be considered in IPI studies and that IPIs may have limited functionality as an identity cue among large groups of conspecifics.
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Affiliation(s)
- Anne Bøttcher
- Department of Bioscience, Zoophysiology, Aarhus University, Denmark
| | - Shane Gero
- Department of Bioscience, Zoophysiology, Aarhus University, Denmark
| | | | - Hal Whitehead
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Peter T Madsen
- Aarhus Institute of Advanced Studies, Høegh-Guldbergs Gade 6B, DK-8000 Aarhus C, Denmark
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Luís AR, Alves IS, Sobreira FV, Couchinho MN, dos Santos ME. Brays and bits: information theory applied to acoustic communication sequences of bottlenose dolphins. BIOACOUSTICS 2018. [DOI: 10.1080/09524622.2018.1443285] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- A. R. Luís
- MARE – Marine and Environmental Sciences Centre, ISPA – Instituto Universitário, Lisboa, Portugal
- Projecto Delfim – Centro Português de Estudo dos Mamíferos Marinhos, Lisboa, Portugal
| | - I. S. Alves
- MARE – Marine and Environmental Sciences Centre, ISPA – Instituto Universitário, Lisboa, Portugal
| | - F. V. Sobreira
- MARE – Marine and Environmental Sciences Centre, ISPA – Instituto Universitário, Lisboa, Portugal
| | - M. N. Couchinho
- MARE – Marine and Environmental Sciences Centre, ISPA – Instituto Universitário, Lisboa, Portugal
- Projecto Delfim – Centro Português de Estudo dos Mamíferos Marinhos, Lisboa, Portugal
| | - M. E. dos Santos
- MARE – Marine and Environmental Sciences Centre, ISPA – Instituto Universitário, Lisboa, Portugal
- Projecto Delfim – Centro Português de Estudo dos Mamíferos Marinhos, Lisboa, Portugal
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36
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Autenrieth M, Ernst A, Deaville R, Demaret F, IJsseldijk LL, Siebert U, Tiedemann R. Putative origin and maternal relatedness of male sperm whales (Physeter macrocephalus) recently stranded in the North Sea. Mamm Biol 2018. [DOI: 10.1016/j.mambio.2017.09.003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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37
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Visser F, Kok AC, Oudejans MG, Scott-Hayward LA, DeRuiter SL, Alves AC, Antunes RN, Isojunno S, Pierce GJ, Slabbekoorn H, Huisman J, Miller PJO. Vocal foragers and silent crowds: context-dependent vocal variation in Northeast Atlantic long-finned pilot whales. Behav Ecol Sociobiol 2017; 71:170. [PMID: 29167596 PMCID: PMC5674111 DOI: 10.1007/s00265-017-2397-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 10/12/2017] [Accepted: 10/13/2017] [Indexed: 11/12/2022]
Abstract
ABSTRACT Vocalisations form a key component of the social interactions and foraging behaviour of toothed whales. We investigated changes in calling and echolocation behaviour of long-finned pilot whales between foraging and non-foraging periods, by combining acoustic recordings and diving depth data from tagged individuals with concurrent surface observations on social behaviour of their group. The pilot whales showed marked vocal variation, specific to foraging and social context. During periods of foraging, pilot whales showed more vocal activity than during non-foraging periods (rest, travel). In addition to the expected increase in echolocation activity, call rates also increased, suggesting that pilot whales communicate more during foraging. Furthermore, calls with multiple inflections occurred more often immediately before and after foraging dives and during the early descent and late ascent phases of foraging dives. However, these calls were almost never detected at diving depths of the tagged whale beyond 350 m. Calls with no or few inflections were produced at all times, irrespective of diving depth of the tagged whale. We discuss possible explanations for the distinct vocal variation associated with foraging periods. In addition, during non-foraging periods, the pilot whales were found to be more silent (no calling or echolocation) in larger, more closely spaced groups. This indicates that increased levels of social cohesion may release the need to stay in touch acoustically. SIGNIFICANCE STATEMENT Social toothed whales rely on vocalisations to find prey and interact with conspecifics. Species are often highly vocal and can have elaborate call repertoires. However, it often remains unclear how their repertoire use correlates to specific social and behavioural contexts, which is vital to understand toothed whale foraging strategies and sociality. Combining on-animal tag recordings of diving and acoustic behaviour with observations of social behaviour, we found that pilot whales produce more calls during foraging than during non-foraging periods. Moreover, highly inflected calls were closely associated to the periods around and during foraging dives. This indicates enhanced communication during foraging, which may, for example, enable relocation of conspecifics or sharing of information. Whales reduced their vocal activity (calling and echolocation) at increased levels of social cohesion, indicating that in certain behavioural contexts, closer association (i.e. more closely spaced) may release the need to stay in touch acoustically.
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Affiliation(s)
- Fleur Visser
- Behavioural Biology, Institute of Biology, Leiden University, Leiden, The Netherlands
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
- Kelp Marine Research, Hoorn, The Netherlands
| | - Annebelle C.M. Kok
- Behavioural Biology, Institute of Biology, Leiden University, Leiden, The Netherlands
| | | | - Lindesay A.S. Scott-Hayward
- Centre for Research into Ecological and Environmental Modelling (CREEM), University of St Andrews, Scotland, UK
| | - Stacy L. DeRuiter
- Centre for Research into Ecological and Environmental Modelling (CREEM), University of St Andrews, Scotland, UK
- Department of Mathematics and Statistics, Calvin College, Grand Rapids, MI USA
| | - Ana C. Alves
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, Scotland, UK
| | - Ricardo N. Antunes
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, Scotland, UK
- Ocean Giants Program, Wildlife Conservation Society, New York, NY USA
| | - Saana Isojunno
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, Scotland, UK
| | - Graham J. Pierce
- Oceanlab, University of Aberdeen, Aberdeenshire, UK
- CESAM and Departamento de Biologia, Universidade de Aveiro, Aveiro, Portugal
- CSIC, Vigo, Spain
| | - Hans Slabbekoorn
- Behavioural Biology, Institute of Biology, Leiden University, Leiden, The Netherlands
| | - Jef Huisman
- Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, The Netherlands
| | - Patrick J. O. Miller
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, Scotland, UK
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Romeu B, Cantor M, Bezamat C, Simões-Lopes PC, Daura-Jorge FG. Bottlenose dolphins that forage with artisanal fishermen whistle differently. Ethology 2017. [DOI: 10.1111/eth.12665] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Bianca Romeu
- Laboratório de Mamíferos Aquáticos; Departamento de Ecologia e Zoologia; Universidade Federal de Santa Catarina; Florianópolis Brazil
| | - Mauricio Cantor
- Laboratório de Mamíferos Aquáticos; Departamento de Ecologia e Zoologia; Universidade Federal de Santa Catarina; Florianópolis Brazil
| | - Carolina Bezamat
- Laboratório de Mamíferos Aquáticos; Departamento de Ecologia e Zoologia; Universidade Federal de Santa Catarina; Florianópolis Brazil
| | - Paulo C. Simões-Lopes
- Laboratório de Mamíferos Aquáticos; Departamento de Ecologia e Zoologia; Universidade Federal de Santa Catarina; Florianópolis Brazil
| | - Fábio G. Daura-Jorge
- Laboratório de Mamíferos Aquáticos; Departamento de Ecologia e Zoologia; Universidade Federal de Santa Catarina; Florianópolis Brazil
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39
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Mann J, Karniski C. Diving beneath the surface: long-term studies of dolphins and whales. J Mammal 2017. [DOI: 10.1093/jmammal/gyx036] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Janet Mann
- Department of Biology, Georgetown University, NW, Washington, DC, USA
| | - Caitlin Karniski
- Department of Biology, Georgetown University, NW, Washington, DC, USA
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Van Cise AM, Roch MA, Baird RW, Aran Mooney T, Barlow J. Acoustic differentiation of Shiho- and Naisa-type short-finned pilot whales in the Pacific Ocean. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2017; 141:737. [PMID: 28253689 DOI: 10.1121/1.4974858] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Divergence in acoustic signals used by different populations of marine mammals can be caused by a variety of environmental, hereditary, or social factors, and can indicate isolation between those populations. Two types of genetically and morphologically distinct short-finned pilot whales, called the Naisa- and Shiho-types when first described off Japan, have been identified in the Pacific Ocean. Acoustic differentiation between these types would support their designation as sub-species or species, and improve the understanding of their distribution in areas where genetic samples are difficult to obtain. Calls from two regions representing the two types were analyzed using 24 recordings from Hawai'i (Naisa-type) and 12 recordings from the eastern Pacific Ocean (Shiho-type). Calls from the two types were significantly differentiated in median start frequency, frequency range, and duration, and were significantly differentiated in the cumulative distribution of start frequency, frequency range, and duration. Gaussian mixture models were used to classify calls from the two different regions with 74% accuracy, which was significantly greater than chance. The results of these analyses indicate that the two types are acoustically distinct, which supports the hypothesis that the two types may be separate sub-species.
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Affiliation(s)
- Amy M Van Cise
- Scripps Institution of Oceanography, University of California-San Diego, La Jolla, California 92038, USA
| | - Marie A Roch
- San Diego State University, San Diego, California 92182, USA
| | - Robin W Baird
- Cascadia Research Collective, Olympia, Washington 98501, USA
| | - T Aran Mooney
- Woods Hole Oceanographic Institution, Massachusetts Institute of Technology, Woods Hole, Massachusetts 02543, USA
| | - Jay Barlow
- National Oceanic and Atmospheric Administration (NOAA)-National Marine Fisheries Service (NMFS) Southwest Fisheries Science Center, La Jolla, California 92037, USA
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Coppinger B, Cannistraci RA, Karaman F, Kyle SC, Hobson EA, Freeberg TM, Hay JF. Studying audience effects in animals: what we can learn from human language research. Anim Behav 2017. [PMID: 29527016 DOI: 10.1016/j.anbehav.2016.12.020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
| | | | - Ferhat Karaman
- Department of Psychology, University of Tennessee, Knoxville, TN, U.S.A
| | - Steven C Kyle
- Department of Psychology, University of Tennessee, Knoxville, TN, U.S.A
| | - Elizabeth A Hobson
- National Institute for Mathematical and Biological Synthesis, University of Tennessee, Knoxville, TN, U.S.A.,ASU-SFI Center for Biosocial Complex Systems, Arizona State University, Tempe, AZ, U.S.A.,Santa Fe Institute, Santa Fe, NM, U.S.A
| | - Todd M Freeberg
- Department of Psychology, University of Tennessee, Knoxville, TN, U.S.A.,Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN, U.S.A.,NeuroNET Research Center, University of Tennessee, Knoxville, TN, U.S.A
| | - Jessica F Hay
- Department of Psychology, University of Tennessee, Knoxville, TN, U.S.A.,NeuroNET Research Center, University of Tennessee, Knoxville, TN, U.S.A
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42
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Gero S, Whitehead H. Critical Decline of the Eastern Caribbean Sperm Whale Population. PLoS One 2016; 11:e0162019. [PMID: 27706153 PMCID: PMC5051958 DOI: 10.1371/journal.pone.0162019] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 08/16/2016] [Indexed: 11/19/2022] Open
Abstract
Sperm whale (Physeter macrocephalus) populations were expected to rebuild following the end of commercial whaling. We document the decline of the population in the eastern Caribbean by tracing demographic changes of well-studied social units. We address hypotheses that, over a ten-year period of dedicated effort (2005–2015), unit size, numbers of calves and/or calving rates have each declined. Across 16 units, the number of adults decreased in 12 units, increased in two, and showed no change in two. The number of adults per unit decreased at -0.195 individuals/yr (95% CI: -0.080 to -0.310; P = 0.001). The number of calves also declined, but the decline was not significant. This negative trend of -4.5% per year in unit size started in about 2010, with numbers being fairly stable until then. There are several natural and anthropogenic threats, but no well-substantiated cause for the decline.
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Affiliation(s)
- Shane Gero
- Zoophysiology, Institute for Bioscience, Aarhus University, Aarhus, Denmark
- * E-mail:
| | - Hal Whitehead
- Dept. of Biology, Dalhousie University, Halifax, Canada
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Cantor M, Whitehead H, Gero S, Rendell L. Cultural turnover among Galápagos sperm whales. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160615. [PMID: 27853582 PMCID: PMC5099007 DOI: 10.1098/rsos.160615] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2016] [Accepted: 09/12/2016] [Indexed: 05/14/2023]
Abstract
While populations may wax and wane, it is rare for an entire population to be replaced by a completely different set of individuals. We document the large-scale relocation of cultural groups of sperm whale off the Galápagos Islands, in which two sympatric vocal clans were entirely replaced by two different ones. Between 1985 and 1999, whales from two clans (called Regular and Plus-One) defined by cultural dialects in coda vocalizations were repeatedly photo-identified off Galápagos. Their occurrence in the area declined through the 1990s; by 2000, none remained. We reassessed Galápagos sperm whales in 2013-2014, identifying 463 new females. However, re-sighting rates were low, with no matches with the Galápagos 1985-1999 population, suggesting an eastward shift to coastal areas. Their vocal repertoires matched those of two other clans (called Short and Four-Plus) found across the Pacific but previously rare or absent around Galápagos. The mechanisms behind this cultural turnover may include large-scale environmental regime shifts favouring clan-specific foraging strategies, and a response to heavy whaling in the region involving redistribution of surviving whales into high-quality habitats. The fall and rise of sperm whale cultures off Galápagos reflect the structuring of the Pacific population into large, enduring clans with dynamic ranges. Long-lasting clan membership illustrates how culture can be bound up in the structure and dynamics of animal populations and so how tracking cultural traits can reveal large-scale population shifts.
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Affiliation(s)
- Mauricio Cantor
- Department of Biology, Dalhousie University, Halifax, Canada
| | - Hal Whitehead
- Department of Biology, Dalhousie University, Halifax, Canada
| | - Shane Gero
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Denmark
| | - Luke Rendell
- School of Biology, University of St. Andrews, St Andrews, UK
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Rendell L, Frantzis A. Mediterranean Sperm Whales, Physeter macrocephalus: The Precarious State of a Lost Tribe. ADVANCES IN MARINE BIOLOGY 2016; 75:37-74. [PMID: 27770991 DOI: 10.1016/bs.amb.2016.08.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
First observed in the classical era, a population of sperm whales (Physeter macrocephalus) persists to this day in the deep waters of the Mediterranean Sea. Genetic and observational evidence support the notion that this is an isolated population, separated from its Atlantic neighbours. These whales depend on mesopelagic squid for food, and appear to occupy a very similar ecological niche to sperm whales in the open oceans. Recent evidence proving that individuals can pass between the eastern and western deep water basins confirms that this is a single population, not isolated into western and eastern stocks. We lack robust information on their population status, but they could number in the hundreds rather than thousands, and current densities appear to be much lower than those reported in the 1950s, suggesting that we should be very concerned about the conservation status of this population. This makes it vitally important to address the serious threats posed by ship strikes and entanglement in fishing nets, especially driftnets, and to carefully monitor other potential sources of anthropogenic impact. A step change in funding to collect better data and a clear shift in policy priorities are needed if we are to be serious about conserving this population.
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Affiliation(s)
- L Rendell
- Sea Mammal Research Unit, University of St Andrews, St Andrews, Fife, United Kingdom.
| | - A Frantzis
- Pelagos Cetacean Research Institute, Vouliagmeni, Greece
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Zwamborn EMJ, Whitehead H. Repeated call sequences and behavioural context in long-finned pilot whales off Cape Breton, Nova Scotia, Canada. BIOACOUSTICS 2016. [DOI: 10.1080/09524622.2016.1233457] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
| | - Hal Whitehead
- Department of Biology, Dalhousie University, Halifax, Canada
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Gero S, Bøttcher A, Whitehead H, Madsen PT. Socially segregated, sympatric sperm whale clans in the Atlantic Ocean. ROYAL SOCIETY OPEN SCIENCE 2016; 3:160061. [PMID: 27429766 PMCID: PMC4929901 DOI: 10.1098/rsos.160061] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Accepted: 05/10/2016] [Indexed: 05/14/2023]
Abstract
Sperm whales (Physeter macrocephalus) are unusual in that there is good evidence for sympatric populations with distinct culturally determined behaviour, including potential acoustic markers of the population division. In the Pacific, socially segregated, vocal clans with distinct dialects coexist; by contrast, geographical variation in vocal repertoire in the Atlantic has been attributed to drift. We examine networks of acoustic repertoire similarity and social interactions for 11 social units in the Eastern Caribbean. We find the presence of two socially segregated, sympatric vocal clans whose dialects differ significantly both in terms of categorical coda types produced by each clan (Mantel test between clans: matrix correlation = 0.256; p ≤ 0.001) and when using classification-free similarity which ignores defined types (Mantel test between clans: matrix correlation = 0.180; p ≤ 0.001). The more common of the two clans makes a characteristic 1 + 1 + 3 coda, while the other less often sighted clan makes predominantly regular codas. Units were only observed associating with other units within their vocal clan. This study demonstrates that sympatric vocal clans do exist in the Atlantic, that they define a higher order level of social organization as they do in the Pacific, and suggests that cultural identity at the clan level is probably important in this species worldwide.
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Affiliation(s)
- Shane Gero
- Department of Zoophysiology, Institute of Bioscience, Aarhus University, Aarhus, Denmark
- Author for correspondence: Shane Gero e-mail:
| | - Anne Bøttcher
- Department of Zoophysiology, Institute of Bioscience, Aarhus University, Aarhus, Denmark
| | - Hal Whitehead
- Department of Biology, Dalhousie University, Halifax, Canada
| | - Peter Teglberg Madsen
- Department of Zoophysiology, Institute of Bioscience, Aarhus University, Aarhus, Denmark
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Oliveira C, Wahlberg M, Silva MA, Johnson M, Antunes R, Wisniewska DM, Fais A, Gonçalves J, Madsen PT. Sperm whale codas may encode individuality as well as clan identity. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2016; 139:2860. [PMID: 27250178 DOI: 10.1121/1.4949478] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Sperm whales produce codas for communication that can be grouped into different types according to their temporal patterns. Codas have led researchers to propose that sperm whales belong to distinct cultural clans, but it is presently unclear if they also convey individual information. Coda clicks comprise a series of pulses and the delay between pulses is a function of organ size, and therefore body size, and so is one potential source of individual information. Another potential individual-specific parameter could be the inter-click intervals within codas. To test whether these parameters provide reliable individual cues, stereo-hydrophone acoustic tags (Dtags) were attached to five sperm whales of the Azores, recording a total of 802 codas. A discriminant function analysis was used to distinguish 288 5 Regular codas from four of the sperm whales and 183 3 Regular codas from two sperm whales. The results suggest that codas have consistent individual features in their inter-click intervals and inter-pulse intervals which may contribute to individual identification. Additionally, two whales produced different coda types in distinct foraging dive phases. Codas may therefore be used by sperm whales to convey information of identity as well as activity within a social group to a larger extent than previously assumed.
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Affiliation(s)
- Cláudia Oliveira
- Marine and Environmental Sciences Centre and Institute of Marine Research, Departamento de Oceanografia e Pescas, Universidade dos Açores, 9901-862 Horta, Portugal
| | - Magnus Wahlberg
- Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - Mónica A Silva
- Marine and Environmental Sciences Centre and Institute of Marine Research, Departamento de Oceanografia e Pescas, Universidade dos Açores, 9901-862 Horta, Portugal
| | - Mark Johnson
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St. Andrews, St. Andrews, Fife KY16 8LB, United Kingdom
| | - Ricardo Antunes
- Ocean Giants Program, Global Conservation Programs, Wildlife Conservation Society, 2300 Southern Boulevard, Bronx, New York 10460, USA
| | - Danuta M Wisniewska
- Zoophysiology, Department of Bioscience, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
| | - Andrea Fais
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine, Bischofsholer Damm 15, 30173 Hannover, Germany
| | - João Gonçalves
- Marine and Environmental Sciences Centre and Institute of Marine Research, Departamento de Oceanografia e Pescas, Universidade dos Açores, 9901-862 Horta, Portugal
| | - Peter T Madsen
- Zoophysiology, Department of Bioscience, Aarhus University, Ny Munkegade 116, DK-8000 Aarhus C, Denmark
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