1
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Ferrari M, Trinh M, Sarano F, Sarano V, Giraudet P, Preud'homme A, Heuzey R, Glotin H. Age and interpulse interval relation from newborn to adult sperm whale (Physeter macrocephalus) off Mauritius. Sci Rep 2024; 14:18474. [PMID: 39122779 PMCID: PMC11316103 DOI: 10.1038/s41598-024-51194-5] [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: 02/16/2023] [Accepted: 01/01/2024] [Indexed: 08/12/2024] Open
Abstract
Sperm whales (Physeter macrocephalus) have been studied for decades, but the development of their clicks during the animal growth is not yet well known. The click they emit during socialization and echolocation contains information about the length of their acoustic organs and, therefore the length of the body through the interpulse interval (IPI). This paper provides the first IPI/age relationship for juvenile male and female sperm whales (Physeter macrocephalus) based on field recordings of individuals whose age is largely known. Across 9 years, audiovisual recordings of a Mauritian sperm whale social unit were carried out. Adult female and juvenile sperm whales were identified and aged. The dataset made from those recordings is publicly available. The interpulse interval was measured for individuals whose ages ranged from 7 days to around 38 years. The growth of the acoustic organ of juveniles showed an early inter-individual variability as well as sexual dimorphism. Usual growth models were also fitted, predicting a mean I P I ∞ of 3.5 ms for adults and a physical maturity reached at around 30 years old. The use of passive acoustic monitoring (PAM) is one of the main tools used to study sperm whales. This IPI-age relationship may aid demographic studies on sperm whales by enabling PAM to assess the ages of recorded sperm whales.
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Affiliation(s)
- Maxence Ferrari
- Université de Toulon, Aix Marseille Université, CNRS, LIS, DYNI, Toulon, France.
- CIAN, International Center of AI for Natural Acoustics, Univ. Toulon, .
| | - Marie Trinh
- Université de Toulon, Aix Marseille Université, CNRS, LIS, DYNI, Toulon, France
| | - François Sarano
- CIAN, International Center of AI for Natural Acoustics, Univ. Toulon, .
- Longitude 181, 12 r. de La Fontaine, 26000, Valence, France.
| | - Véronique Sarano
- CIAN, International Center of AI for Natural Acoustics, Univ. Toulon, .
- Longitude 181, 12 r. de La Fontaine, 26000, Valence, France.
| | - Pascale Giraudet
- Université de Toulon, Aix Marseille Université, CNRS, LIS, DYNI, Toulon, France.
- CIAN, International Center of AI for Natural Acoustics, Univ. Toulon, .
| | - Axel Preud'homme
- CIAN, International Center of AI for Natural Acoustics, Univ. Toulon
- Indian Ocean Marine Life Foundation, 44, La bourdonnais Street, Port Louis, Mauritius
| | - René Heuzey
- CIAN, International Center of AI for Natural Acoustics, Univ. Toulon
- Indian Ocean Marine Life Foundation, 44, La bourdonnais Street, Port Louis, Mauritius
| | - Hervé Glotin
- Université de Toulon, Aix Marseille Université, CNRS, LIS, DYNI, Toulon, France.
- CIAN, International Center of AI for Natural Acoustics, Univ. Toulon, .
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2
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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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3
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Pöyhönen V, Thomisch K, Kovacs KM, Lydersen C, Ahonen H. High Arctic "hotspots" for sperm whales (Physeter macrocephalus) off western and northern Svalbard, Norway, revealed by multi-year Passive Acoustic Monitoring (PAM). Sci Rep 2024; 14:5825. [PMID: 38461150 PMCID: PMC10924940 DOI: 10.1038/s41598-024-56287-9] [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: 11/30/2023] [Accepted: 03/05/2024] [Indexed: 03/11/2024] Open
Abstract
Despite the well-documented, broad global distribution of sperm whales (Physeter macrocephalus), their distributional patterns remain poorly known in Arctic regions, where year-round monitoring is challenging. Adult male sperm whales are known to migrate seasonally between nutrient-rich high latitude waters and low latitude breeding grounds. However, knowledge is limited regarding fine-scale distribution and seasonal presence at high latitudes. To investigate the acoustic occurrence of this vocally active species in the High Arctic of the Northeast Atlantic, this study combined automated and manual click detection methods to analyze passive acoustic data collected at eight locations around the Svalbard Archipelago, Norway, between 2012 and 2021. The results revealed the presence of sperm whales at six recording sites and demonstrated sperm whale "hotspots" in ice-free areas in eastern Fram Strait along the shelf break and close to the west coast of Spitsbergen from May-January, with some variation between years and locations. Although acoustic presence decreased with increasing latitude, even the northern-most location (81° N) recorded sperm whale vocal activity between August and January. This study provides a baseline for sperm whale acoustic presence in the High Arctic, which will be essential in the context of detecting future changes and also for predicting future distribution patterns in the rapidly changing Arctic marine environment.
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Affiliation(s)
- Viivi Pöyhönen
- Norwegian Polar Institute, Fram Centre, 9296, Tromsø, Norway
| | - Karolin Thomisch
- Ocean Acoustics Group of the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, 27570, Bremerhaven, Germany
| | - Kit M Kovacs
- Norwegian Polar Institute, Fram Centre, 9296, Tromsø, Norway
| | | | - Heidi Ahonen
- Norwegian Polar Institute, Fram Centre, 9296, Tromsø, Norway.
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4
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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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5
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Madsen PT, Siebert U, Elemans CPH. Toothed whales use distinct vocal registers for echolocation and communication. Science 2023; 379:928-933. [PMID: 36862790 DOI: 10.1126/science.adc9570] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023]
Abstract
Echolocating toothed whales (odontocetes) capture fast-moving prey in dark marine environments, which critically depends on their ability to generate powerful, ultrasonic clicks. How their supposedly air-driven sound source can produce biosonar clicks at depths of >1000 meters, while also producing rich vocal repertoires to mediate complex social communication, remains unknown. We show that odontocetes possess a sound production system based on air driven through nasal passages that is functionally analogous to laryngeal and syringeal sound production. Tissue vibration in different registers produces distinct echolocation and communication signals across all major odontocete clades, and thus provides a physiological basis for classifying their vocal repertoires. The vocal fry register is used by species from porpoises to sperm whales for generating powerful, highly air-efficient echolocation clicks.
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Affiliation(s)
- Peter T Madsen
- Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark
| | - Ursula Siebert
- Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover, 25761 Büsum, Germany
| | - Coen P H Elemans
- Sound Communication and Behavior Group, Department of Biology, University of Southern Denmark, 5230 Odense M, Denmark
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6
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Westell A, Sakai T, Valtierra R, Van Parijs SM, Cholewiak D, DeAngelis A. Sperm whale acoustic abundance and dive behaviour in the western North Atlantic. Sci Rep 2022; 12:16821. [PMID: 36207450 PMCID: PMC9546825 DOI: 10.1038/s41598-022-20868-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 09/20/2022] [Indexed: 11/24/2022] Open
Abstract
Sperm whales are an ideal species to study using passive acoustic technology because they spend the majority of their time underwater and produce echolocation clicks almost continuously while foraging. Passive acoustic line transect data collected between June and August 2016 were used to estimate a depth-corrected acoustic abundance and study the dive behaviour of foraging sperm whales in the western North Atlantic Ocean. 2D localizations (n = 699) were truncated at a slant range of 6500 m and combined with the multipath arrivals of surface reflected echoes to calculate 3D localizations (n = 274). Distance sampling using depth-corrected perpendicular distances resulted in a 10.5% change in the acoustic abundance estimate (2199 whales, CV = 14.6%) compared to uncorrected slant ranges (1969 whales, CV = 14.1%), and a detection function that was a better fit for the data. Sperm whales exhibited multiple foraging strategies, with bottom phases occurring at depths of 400–800, 800–1200, or > 1200 m, accounting for an average 39.2, 49.5, or 44.9% of the total recorded dive time, respectively. These results suggest that estimating 3D localizations using acoustic line transect data improves acoustic abundance estimation and can be used to answer population level questions about foraging ecology.
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Affiliation(s)
- Annabel Westell
- Under Contract to the Northeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 166 Water Street, Woods Hole, MA, 02543, USA.
| | - Taiki Sakai
- Environmental Assessment Services, LLC, 350 Hills St., Suite 112, Richland, WA, 99354, USA.,Under Contract to the Southwest Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 8901 La Jolla Shores Drive, La Jolla, CA, 92037, USA
| | - Robert Valtierra
- Marine Acoustics Inc., 2 Corporate Pl #105, Middletown, RI, 02842, USA
| | - Sofie M Van Parijs
- Northeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 166 Water Street, Woods Hole, MA, 02543, USA
| | - Danielle Cholewiak
- Northeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 166 Water Street, Woods Hole, MA, 02543, USA
| | - Annamaria DeAngelis
- Northeast Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 166 Water Street, Woods Hole, MA, 02543, USA
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7
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King SL, Jensen FH. Rise of the machines: Integrating technology with playback experiments to study cetacean social cognition in the wild. Methods Ecol Evol 2022. [DOI: 10.1111/2041-210x.13935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stephanie L. King
- School of Biological Sciences University of Bristol BS8 1TQ Bristol United Kingdom
| | - Frants H. Jensen
- Biology department, Syracuse University 107 College Place 13244 Syracuse NY USA
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8
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Acoustic discrimination in the grey bamboo shark Chiloscyllium griseum. Sci Rep 2022; 12:6520. [PMID: 35444192 PMCID: PMC9021286 DOI: 10.1038/s41598-022-10257-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Accepted: 04/05/2022] [Indexed: 12/03/2022] Open
Abstract
Cognitive abilities of sharks are well developed and comparable to teleosts and other vertebrates. Most studies exploring elasmobranch cognitive abilities have used visual stimuli, assessing a wide range of discrimination tasks, memory retention and spatial learning abilities. Some studies using acoustic stimuli in a cognitive context have been conducted, but a basic understanding of sound induced behavioural changes and the underlying mechanisms involved are still lacking. This study explored the acoustic discrimination abilities of seven juvenile grey bamboo sharks (Chiloscyllium griseum) using a Go/No-Go method, which so far had never been tested in sharks before. After this, the smallest frequency difference leading to a change in behaviour in the sharks was studied using a series of transfer tests. Our results show that grey bamboo sharks can learn a Go/No-Go task using both visual and acoustic stimuli. Transfer tests elucidated that, when both stimulus types were presented, both were used. Within the tested range of 90–210 Hz, a frequency difference of 20–30 Hz is sufficient to discriminate the two sounds, which is comparable to results previously collected for sharks and teleosts. Currently, there is still a substantial lack of knowledge concerning the acoustic abilities and sound induced behaviours of sharks while anthropogenic noise is constantly on the rise. New insights into shark sound recognition, detection and use are therefore of the utmost importance and will aid in management and conservation efforts of sharks.
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9
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Poupard M, Ferrari M, Best P, Glotin H. Passive acoustic monitoring of sperm whales and anthropogenic noise using stereophonic recordings in the Mediterranean Sea, North West Pelagos Sanctuary. Sci Rep 2022; 12:2007. [PMID: 35132115 PMCID: PMC8821711 DOI: 10.1038/s41598-022-05917-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 01/13/2022] [Indexed: 12/02/2022] Open
Abstract
A total of 147 days spread over 4 years were recorded by a stereophonic sonobuoy set up in the Mediterranean sea, near the coast of Toulon, south of France. These recordings were analyzed in the scope of studying sperm whales (Physeter macrocephalus) and the impact anthropic noises may have on this species. With the use of a novel approach, which combines the use of a stereophonic antenna with a neural network, 226 sperm whales’ passages have been automatically detected in an effective range of 32 km. This dataset was then used to analyze the sperm whales’ abundance, the background noise, the influence of the background noise on the acoustic presence, and the animals’ size. The results show that sperm whales are present all year round in groups of 1–9 individuals, especially during the daytime. The estimated density is 1.69 whales/1000 km\documentclass[12pt]{minimal}
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\begin{document}$$^2$$\end{document}2. Animals were also less frequent during periods with an increased background noise due to ferries. The animal size distribution revealed the recorded sperm whales were distributed in length from about 7 to 15.5 m, and lonely whales are larger, while groups of two are composed of juvenile and mid-sized animals.
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Affiliation(s)
- Marion Poupard
- Université de Toulon, Aix Marseille Univ., CNRS, LIS, DYNI, Marseille, France.
| | - Maxence Ferrari
- Université de Toulon, Aix Marseille Univ., CNRS, LIS, DYNI, Marseille, France
| | - Paul Best
- Université de Toulon, Aix Marseille Univ., CNRS, LIS, DYNI, Marseille, France
| | - Hervé Glotin
- Université de Toulon, Aix Marseille Univ., CNRS, LIS, DYNI, Marseille, France.,Université de Toulon, INPS, SMIoT, Marseille, France
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10
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Stidsholt L, Johnson M, Goerlitz HR, Madsen PT. Wild bats briefly decouple sound production from wingbeats to increase sensory flow during prey captures. iScience 2021; 24:102896. [PMID: 34401675 PMCID: PMC8355945 DOI: 10.1016/j.isci.2021.102896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 06/21/2021] [Accepted: 07/20/2021] [Indexed: 10/28/2022] Open
Abstract
Active sensing animals such as echolocating bats produce the energy with which they probe their environment. The intense echolocation calls of bats are energetically expensive, but their cost can be reduced by synchronizing the exhalations needed to vocalize to wingbeats. Here, we use sound-and-movement recording tags to investigate how wild bats balance efficient sound production with information needs during foraging and navigation. We show that wild bats prioritize energy efficiency over sensory flow when periodic snapshots of the acoustic scene are sufficient during travel and search. Rapid calls during tracking and interception of close prey are decoupled from the wingbeat but are weaker and comprise <2% of all calls during a night of hunting. The limited use of fast sonar sampling provides bats with high information update rates during critical hunting moments but adds little to their overall costs of sound production despite the inefficiency of decoupling calls from wingbeats.
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Affiliation(s)
- Laura Stidsholt
- Zoophysiology, Department of Biology, Aarhus University, Aarhus, Denmark
| | - Mark Johnson
- Aarhus Institute of Advanced Studies, Aarhus University, Aarhus, Denmark
| | - Holger R Goerlitz
- Acoustic and Functional Ecology, Max Planck Institute for Ornithology, Seewiesen, Germany
| | - Peter T Madsen
- Zoophysiology, Department of Biology, Aarhus University, Aarhus, Denmark
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11
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Malinka CE, Tønnesen P, Dunn CA, Claridge DE, Gridley T, Elwen SH, Teglberg Madsen P. Echolocation click parameters and biosonar behaviour of the dwarf sperm whale ( Kogia sima). J Exp Biol 2021; 224:224/6/jeb240689. [PMID: 33771935 DOI: 10.1242/jeb.240689] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Accepted: 02/11/2021] [Indexed: 11/20/2022]
Abstract
Dwarf sperm whales (Kogia sima) are small toothed whales that produce narrow-band high-frequency (NBHF) echolocation clicks. Such NBHF clicks, subject to high levels of acoustic absorption, are usually produced by small, shallow-diving odontocetes, such as porpoises, in keeping with their short-range echolocation and fast click rates. Here, we sought to address the problem of how the little-studied and deep-diving Kogia can hunt with NBHF clicks in the deep sea. Specifically, we tested the hypotheses that Kogia produce NBHF clicks with longer inter-click intervals (ICIs), higher directionality and higher source levels (SLs) compared with other NBHF species. We did this by deploying an autonomous deep-water vertical hydrophone array in the Bahamas, where no other NBHF species are present, and by taking opportunistic recordings of a close-range Kogia sima in a South African harbour. Parameters from on-axis clicks (n=46) in the deep revealed very narrow-band clicks (root mean squared bandwidth, BWRMS, of 3±1 kHz), with SLs of up to 197 dB re. 1 µPa peak-to-peak (μPapp) at 1 m, and a half-power beamwidth of 8.8 deg. Their ICIs (mode of 245 ms) were much longer than those of porpoises (<100 ms), suggesting an inspection range that is longer than detection ranges of single prey, perhaps to facilitate auditory streaming of a complex echo scene. On-axis clicks in the shallow harbour (n=870) had ICIs and SLs in keeping with source parameters of other NBHF cetaceans. Thus, in the deep, dwarf sperm whales use a directional, but short-range echolocation system with moderate SLs, suggesting a reliable mesopelagic prey habitat.
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Affiliation(s)
- Chloe E Malinka
- Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark
| | - Pernille Tønnesen
- Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus, Denmark
| | - Charlotte A Dunn
- Bahamas Marine Mammal Research Organisation (BMMRO), Sandy Point, Abaco, Bahamas.,Sea Mammal Research Unit, University of St Andrews, St Andrews KY16 8LB, UK
| | - Diane E Claridge
- Bahamas Marine Mammal Research Organisation (BMMRO), Sandy Point, Abaco, Bahamas.,Sea Mammal Research Unit, University of St Andrews, St Andrews KY16 8LB, UK
| | - Tess Gridley
- Department of Botany and Zoology, Stellenbosch University, Stellenbosch 7605, South Africa.,Sea Search Research and Conservation, Muizenberg, Cape Town 7945, South Africa
| | - Simon H Elwen
- Department of Botany and Zoology, Stellenbosch University, Stellenbosch 7605, South Africa.,Sea Search Research and Conservation, Muizenberg, Cape Town 7945, South Africa
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12
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Trumpet sounds emitted by male sperm whales in the Mediterranean Sea. Sci Rep 2021; 11:5867. [PMID: 33712633 PMCID: PMC7955081 DOI: 10.1038/s41598-021-84126-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Accepted: 02/11/2021] [Indexed: 01/31/2023] Open
Abstract
Sperm whale trumpets are sounds only occasionally documented, with a well recognisable and stereotyped acoustic arrangement. This study investigated the acoustic features of the trumpets and the context in which these sounds were recorded, using acoustic data collected over 22 years, in the Pelagos Sanctuary area (North-Western Mediterranean Sea). Analysed trumpets (n = 230), recorded at the beginning of a dive after the whale fluke-up, comprised a series of acoustic units organized in short sequences. Acoustic parameters were derived for the entire trumpet and for each distinguishable unit in a trumpet. Overall, trumpet durations and their initial frequencies were higher in recordings collected when multiple whales were visually or acoustically detected in the observation area. The identity of 68 whales was assessed through photo-identification, with 29 individuals producing trumpets within and between years. The variability of the acoustic parameters appeared to be higher within the same individuals rather than between different individuals, suggesting an individual plasticity in composing and arranging units in a trumpet. Different click patterns were observed before and after the trumpets, with more complex sequences when (1) other whales were visually/acoustically detected, and (2) individuals were in suitable foraging sites (i.e., canyon areas). Trumpets were commonly followed or preceded by click patterns suited for communication, such as codas and/or slow clicks. Significant relations between the trumpet emission and the male-only long-range communication click pattern (i.e. slow clicks) emerged, supporting the hypothesis that a trumpet is a sound emitted by maturing/mature males in feeding grounds. This study provides the first evidence that trumpets were conserved in the sperm whale acoustic repertoire at the decadal timescale, persisting across years and individuals in the same area. This persistence may be functionally specific to foraging activities performed by males in a well-established feeding area.
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13
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Pedersen MB, Tønnesen P, Malinka CE, Ladegaard M, Johnson M, Aguilar de Soto N, Madsen PT. Echolocation click parameters of short-finned pilot whales (Globicephala macrorhynchus) in the wild. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2021; 149:1923. [PMID: 33765819 DOI: 10.1121/10.0003762] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 02/23/2021] [Indexed: 06/12/2023]
Abstract
Short-finned pilot whales (Globicephala macrorhynchus) are large, deep-diving predators with diverse foraging strategies, but little is known about their echolocation. To quantify the source properties of short-finned pilot whale clicks, we made 15 deployments off the coast of Tenerife of a deep-water hydrophone array consisting of seven autonomous time-synced hydrophone recorders (SoundTraps), enabling acoustic localization and quantification of click source parameters. Of 8185 recorded pilot whale clicks, 47 were classified as being recorded on-axis, with a mean peak-to-peak source level (SL) of 181 ± 7 dB re 1 μPa, a centroid frequency of 40 ± 4 kHz, and a duration of 57 ± 23 μs. A fit to a piston model yielded an estimated half-power (-3 dB) beam width of 13.7° [95% confidence interval (CI) 13.2°-14.5°] and a mean directivity index (DI) of 22.6 dB (95% CI 22.5-22.9 dB). These measured SLs and DIs are surprisingly low for a deep-diving toothed whale, suggesting we sampled the short-finned pilot whales in a context with little need for operating a long-range biosonar. The substantial spectral overlap with beaked whale clicks emitted in similar deep-water habitats implies that pilot whale clicks may constitute a common source of false detections in beaked whale passive acoustic monitoring efforts.
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Affiliation(s)
- M B Pedersen
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - P Tønnesen
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - C E Malinka
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - M Ladegaard
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
| | - M Johnson
- Aarhus Institute of Advanced Studies, Aarhus University, 8000 Aarhus C, Denmark
| | - N Aguilar de Soto
- Biodiversidad, Ecología Marina y Conservación (BIOECOMAC), University of La Laguna, 38206 La Laguna, Tenerife, Canary Islands, Spain
| | - P T Madsen
- Marine Bioacoustics Lab, Zoophysiology, Department of Biology, Aarhus University, 8000 Aarhus C, Denmark
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14
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Morano JL, Tielens JT, Muirhead CA, Estabrook BJ, Sullivan PJ, Dugan PJ, Clark CW, Rice AN. Seasonal movements of Gulf of Mexico sperm whales following the Deepwater Horizon oil spill and the limitations of impact assessments. MARINE POLLUTION BULLETIN 2020; 161:111627. [PMID: 33096406 DOI: 10.1016/j.marpolbul.2020.111627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 06/11/2023]
Abstract
As part of the Deepwater Horizon Oil Spill Natural Resource Damage Assessment in the Gulf of Mexico, we conducted a large passive acoustic survey across the eastern Gulf continental shelf edge to assess impacts to sperm whale population. In the months immediately after the spill, sperm whale occurrence was significantly higher in areas closest to the spill. Over the following seasons in 2010-2011, we documented cyclical patterns of decreased and increased occurrence suggesting that this population exhibits a seasonal occurrence pattern in the region, with seasonal movements to other regions, and not likely directly influenced by the oil spill. Unfortunately, a lack of adequately scaled, pre-spill data on sperm whales, along with limitations on the survey duration constrain our ability to infer spill-related changes in sperm whale occurrence. However, our study establishes post-disaster baseline data for continued monitoring, and an expanded study design could provide a model for continued monitoring.
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Affiliation(s)
- Janelle L Morano
- Center for Conservation Bioacoustics, Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA; Department of Natural Resources and the Environment, Cornell University, Ithaca, NY 14853, USA.
| | - Jamey T Tielens
- Center for Conservation Bioacoustics, Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA
| | - Charles A Muirhead
- Center for Conservation Bioacoustics, Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA
| | - Bobbi J Estabrook
- Center for Conservation Bioacoustics, Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA
| | - Patrick J Sullivan
- Department of Natural Resources and the Environment, Cornell University, Ithaca, NY 14853, USA
| | - Peter J Dugan
- Center for Conservation Bioacoustics, Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA
| | - Christopher W Clark
- Center for Conservation Bioacoustics, Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA
| | - Aaron N Rice
- Center for Conservation Bioacoustics, Cornell Lab of Ornithology, Cornell University, Ithaca, NY 14850, USA
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15
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Coombs EJ, Clavel J, Park T, Churchill M, Goswami A. Wonky whales: the evolution of cranial asymmetry in cetaceans. BMC Biol 2020; 18:86. [PMID: 32646447 PMCID: PMC7350770 DOI: 10.1186/s12915-020-00805-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Accepted: 06/01/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Unlike most mammals, toothed whale (Odontoceti) skulls lack symmetry in the nasal and facial (nasofacial) region. This asymmetry is hypothesised to relate to echolocation, which may have evolved in the earliest diverging odontocetes. Early cetaceans (whales, dolphins, and porpoises) such as archaeocetes, namely the protocetids and basilosaurids, have asymmetric rostra, but it is unclear when nasofacial asymmetry evolved during the transition from archaeocetes to modern whales. We used three-dimensional geometric morphometrics and phylogenetic comparative methods to reconstruct the evolution of asymmetry in the skulls of 162 living and extinct cetaceans over 50 million years. RESULTS In archaeocetes, we found asymmetry is prevalent in the rostrum and also in the squamosal, jugal, and orbit, possibly reflecting preservational deformation. Asymmetry in odontocetes is predominant in the nasofacial region. Mysticetes (baleen whales) show symmetry similar to terrestrial artiodactyls such as bovines. The first significant shift in asymmetry occurred in the stem odontocete family Xenorophidae during the Early Oligocene. Further increases in asymmetry occur in the physeteroids in the Late Oligocene, Squalodelphinidae and Platanistidae in the Late Oligocene/Early Miocene, and in the Monodontidae in the Late Miocene/Early Pliocene. Additional episodes of rapid change in odontocete skull asymmetry were found in the Mid-Late Oligocene, a period of rapid evolution and diversification. No high-probability increases or jumps in asymmetry were found in mysticetes or archaeocetes. Unexpectedly, no increases in asymmetry were recovered within the highly asymmetric ziphiids, which may result from the extreme, asymmetric shape of premaxillary crests in these taxa not being captured by landmarks alone. CONCLUSIONS Early ancestors of living whales had little cranial asymmetry and likely were not able to echolocate. Archaeocetes display high levels of asymmetry in the rostrum, potentially related to directional hearing, which is lost in early neocetes-the taxon including the most recent common ancestor of living cetaceans. Nasofacial asymmetry becomes a significant feature of Odontoceti skulls in the Early Oligocene, reaching its highest levels in extant taxa. Separate evolutionary regimes are reconstructed for odontocetes living in acoustically complex environments, suggesting that these niches impose strong selective pressure on echolocation ability and thus increased cranial asymmetry.
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Affiliation(s)
- Ellen J Coombs
- Genetics, Evolution, and Environment Department, University College London, Gower Street, London, WC1E 6BT, UK.
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK.
| | - Julien Clavel
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS, ENTPE, UMR 5023 LEHNA, F-69622, Villeurbanne, France
| | - Travis Park
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
- Department of Earth Sciences, University of Oxford, Oxford, OX1 3AN, UK
| | - Morgan Churchill
- Department of Biology, University of Wisconsin-Oshkosh, Oshkosh, WI, 54901, USA
| | - Anjali Goswami
- Genetics, Evolution, and Environment Department, University College London, Gower Street, London, WC1E 6BT, UK
- Department of Life Sciences, Natural History Museum, London, Cromwell Road, London, SW7 5BD, UK
- Department of Earth Sciences, University College London, Gower Street, London, WC1E 6BT, UK
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16
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Stimpert AK, Lammers MO, Pack AA, Au WWL. Variations in received levels on a sound and movement tag on a singing humpback whale: Implications for caller identification. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2020; 147:3684. [PMID: 32486778 DOI: 10.1121/10.0001306] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 05/05/2020] [Indexed: 06/11/2023]
Abstract
Bio-logging devices are advancing the understanding of marine animal behavior, but linking sound production and behavior of individual baleen whales is still unreliable. Tag placement potentially within the near field of the sound source creates uncertainty about how tagged animal sounds will register on recorders. This study used data from a tagged singing humpback whale to evaluate this question of how sound levels present on a tag when calls are produced by a tagged animal. Root-mean-square (rms) received levels (RLs) of song units ranged from 112 to 164 dB re 1 μPa rms, with some, but not all, of the lower frequency units registering on the tag's 800 Hz accelerometer sensor. Fifty-nine percent of recorded units measured lower acoustic RLs than previously reported source levels for humpback song, but signal-to-noise ratios (SNRs) were 30-45 dB during periods of the dive with low noise. This research highlights that tag RL does not alone predict caller identity, argues for higher SNR thresholds if using SNR to inform decisions about the source of a call, and provides a baseline for future research identifying diagnostic properties of tagged animal calls in cetacean bioacoustic tag datasets.
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Affiliation(s)
- Alison K Stimpert
- Bioacoustics and Vertebrate Ecology, Moss Landing Marine Laboratories, 8272 Moss Landing Road, Moss Landing, California 95039, USA
| | - Marc O Lammers
- Hawaiian Islands Humpback Whale National Marine Sanctuary, National Oceanic and Atmospheric Administration, 726 South Kihei Road, Kihei, Hawaii 96753, USA
| | - Adam A Pack
- Departments of Psychology and Biology and LOHE Bioacoustics Laboratory, University of Hawaii at Hilo, Hilo, Hawaii 96720, USA
| | - Whitlow W L Au
- Hawaii Institute of Marine Biology, 46-007 Lilipuna Road, Kaneohe, Hawaii 96744, USA
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17
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Schmidt FN, Delsmann MM, Mletzko K, Yorgan TA, Hahn M, Siebert U, Busse B, Oheim R, Amling M, Rolvien T. Ultra-high matrix mineralization of sperm whale auditory ossicles facilitates high sound pressure and high-frequency underwater hearing. Proc Biol Sci 2019; 285:20181820. [PMID: 30963901 DOI: 10.1098/rspb.2018.1820] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The auditory ossicles-malleus, incus and stapes-are the smallest bones in mammalian bodies and enable stable sound transmission to the inner ear. Sperm whales are one of the deepest diving aquatic mammals that produce and perceive sounds with extreme loudness greater than 180 dB and frequencies higher than 30 kHz. Therefore, it is of major interest to decipher the microstructural basis for these unparalleled hearing abilities. Using a suite of high-resolution imaging techniques, we reveal that auditory ossicles of sperm whales are highly functional, featuring an ultra-high matrix mineralization that is higher than their teeth. On a micro-morphological and cellular level, this was associated with osteonal structures and osteocyte lacunar occlusions through calcified nanospherites (i.e. micropetrosis), while the bones were characterized by a higher hardness compared to a vertebral bone of the same animals as well as to human auditory ossicles. We propose that the ultra-high mineralization facilitates the unique hearing ability of sperm whales. High matrix mineralization represents an evolutionary conserved or convergent adaptation to middle ear sound transmission.
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Affiliation(s)
- Felix N Schmidt
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Maximilian M Delsmann
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Kathrin Mletzko
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Timur A Yorgan
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Michael Hahn
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Ursula Siebert
- 2 Institute for Terrestrial and Aquatic Wildlife Research, University of Veterinary Medicine Hannover , Foundation, Werftstrasse 6, 25761 Buesum , Germany
| | - Björn Busse
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Ralf Oheim
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Michael Amling
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany
| | - Tim Rolvien
- 1 Department of Osteology and Biomechanics, University Medical Center Hamburg-Eppendorf , Lottestrasse 59, 22529 Hamburg , Germany.,3 Department of Orthopedics, University Medical Center Hamburg-Eppendorf , Martinistrasse 52, 20246 Hamburg , Germany
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18
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Giorli G, Goetz KT. Foraging activity of sperm whales (Physeter macrocephalus) off the east coast of New Zealand. Sci Rep 2019; 9:12182. [PMID: 31434937 PMCID: PMC6704262 DOI: 10.1038/s41598-019-48417-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Accepted: 07/31/2019] [Indexed: 11/09/2022] Open
Abstract
The occurrence and distribution of sperm whales in New Zealand waters is mainly known from whaling records or opportunistic sightings by the public and a systematic estimation of the abundance and distribution has never been conducted. In this study, we investigated the foraging activity and occurrence of sperm whales off the Eastern coast of New Zealand using passive acoustic monitoring techniques. Three acoustic recorders were moored to the ocean floor at different locations on the east side of the North and South Island to collect passive acoustic data from June 2016 until August 2017. A total of 53,823 echolocation click trains were recorded and analyzed to understand the spatial and temporal variation of sperm whale foraging activity. No difference in the foraging activity was found between night-time and day-time periods at any of the locations. Click train detections increased toward the south, suggesting increased foraging activity near Kaikoura. At each station, sperm whale foraging activity varied by month.
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Affiliation(s)
- Giacomo Giorli
- National Institute of Water and Atmospheric Research, Coasts and Oceans, 301 Evans Bay Parade, Greta Point, Wellington, 6021, New Zealand.
| | - Kimberly T Goetz
- Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, National Oceanic and Atmospheric Administration, 7600 Sand Point Way N.E., Seattle, Washington, 98115-6349, USA
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19
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Girola E, Noad MJ, Dunlop RA, Cato DH. Source levels of humpback whales decrease with frequency suggesting an air-filled resonator is used in sound production. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2019; 145:869. [PMID: 30823805 DOI: 10.1121/1.5090492] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 01/25/2019] [Indexed: 05/26/2023]
Abstract
Source level and frequency are important in determining how far an acoustic signal can travel. However, in some species these sound characteristics have been found to be biomechanically linked, and therefore cannot be modified independently to achieve optimal transmission. This study investigates the variability in source levels and their relationship with frequency in the songs of humpback whales (Megaptera novaeangliae). Songs were recorded off eastern Australia using a fixed hydrophone array deployed on the whales' migratory corridor. Singing whales were acoustically tracked. An empirical, frequency-dependent model was used to estimate transmission loss. Source levels and frequency were measured for 2408 song units from 19 singers. Source levels varied from 138 to 187 dB re 1 μPa at 1 m (root mean squared), while peak frequency ranged between 52 and 3877 Hz. Much of the variability in source levels was accounted for by differences between the unit types, with mean source levels for each unit type varying by up to 17 dB. Source levels were negatively correlated with peak frequency and decreased by 2.3 dB per octave. The negative correlation between source levels and frequency is consistent with the presence of an air-filled resonator in the whales' sound production system.
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Affiliation(s)
- Elisa Girola
- Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science, University of Queensland, Gatton, Queensland 4343, Australia
| | - Michael J Noad
- Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science, University of Queensland, Gatton, Queensland 4343, Australia
| | - Rebecca A Dunlop
- Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science, University of Queensland, Gatton, Queensland 4343, Australia
| | - Douglas H Cato
- School of Geosciences, University of Sydney, Sydney, New South Wales 2006, Australia
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20
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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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21
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De Vreese S, van der Schaar M, Weissenberger J, Erbs F, Kosecka M, Solé M, André M. Marine mammal acoustic detections in the Greenland and Barents Sea, 2013 - 2014 seasons. Sci Rep 2018; 8:16882. [PMID: 30442965 PMCID: PMC6237968 DOI: 10.1038/s41598-018-34624-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Accepted: 10/17/2018] [Indexed: 11/24/2022] Open
Abstract
While the Greenland and Barents Seas are known habitats for several cetacean and pinniped species there is a lack of long-term monitoring data in this rapidly changing environment. Moreover, little is known of the ambient soundscapes, and increasing off-shore anthropogenic activities can influence the ecosystem and marine life. Baseline acoustic data is needed to better assess current and future soundscape and ecosystem conditions. The analysis of a year of continuous data from three passive acoustic monitoring devices revealed species-dependent seasonal and spatial variation of a large variety of marine mammals in the Greenland and Barents Seas. Sampling rates were 39 and 78 kHz in the respective locations, and all systems were operational at a duty cycle of 2 min on, 30 min off. The research presents a description of cetacean and pinniped acoustic detections along with a variety of unknown low-frequency tonal sounds, and ambient sound level measurements that fall within the scope of the European Marine Strategy Framework (MSFD). The presented data shows the importance of monitoring Arctic underwater biodiversity for assessing the ecological changes under the scope of climate change.
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Affiliation(s)
- Steffen De Vreese
- Laboratory of Applied Bioacoustics, Technical University of Catalonia (UPC), BarcelonaTech, Rambla Exposición s/n, 08800, Vilanova i la Geltrú, Spain
| | - Mike van der Schaar
- Laboratory of Applied Bioacoustics, Technical University of Catalonia (UPC), BarcelonaTech, Rambla Exposición s/n, 08800, Vilanova i la Geltrú, Spain
| | | | - Florence Erbs
- Laboratory of Applied Bioacoustics, Technical University of Catalonia (UPC), BarcelonaTech, Rambla Exposición s/n, 08800, Vilanova i la Geltrú, Spain
| | - Monika Kosecka
- Laboratory of Applied Bioacoustics, Technical University of Catalonia (UPC), BarcelonaTech, Rambla Exposición s/n, 08800, Vilanova i la Geltrú, Spain
| | - Marta Solé
- Laboratory of Applied Bioacoustics, Technical University of Catalonia (UPC), BarcelonaTech, Rambla Exposición s/n, 08800, Vilanova i la Geltrú, Spain
| | - Michel André
- Laboratory of Applied Bioacoustics, Technical University of Catalonia (UPC), BarcelonaTech, Rambla Exposición s/n, 08800, Vilanova i la Geltrú, Spain.
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22
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Semple SL, Mulder IM, Rodriguez-Ramos T, Power M, Dixon B. Long-term implantation of acoustic transmitters induces chronic inflammatory cytokine expression in adult rainbow trout (Oncorhynchus mykiss). Vet Immunol Immunopathol 2018; 205:1-9. [PMID: 30458996 DOI: 10.1016/j.vetimm.2018.10.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 10/08/2018] [Accepted: 10/14/2018] [Indexed: 12/31/2022]
Abstract
Telemetry transmitters are frequently used in studies of wild fish migration and behavior. Although the effects of surgically implanted transmitters on survival, tag retention, healing and growth have been studied, there has been little research regarding the potential immune response induced by these transmitters. In the current study, mature rainbow trout received either surgical implantation of an acoustic transmitter or a sham surgical procedure. These fish were then sampled over a 10-week period so that pro-inflammatory cytokine expression in the spleen, peritoneal cavity lymphocytes and muscle at the surgical site could be analyzed. There were no significant differences in transcript expression for the spleen and muscle tissue between fish that had a transmitter and those that received the surgical procedure alone. However, transmitter presence significantly increased the expression of IL-6, IL-1β and TNFα in the peritoneal cells at 10 weeks indicating that tagged fish may be coping with chronic inflammation. Furthermore, tagged male fish had a higher inflammatory response in 10-week peritoneal lavage samples when compared to their tagged mature female counterparts, providing some evidence that mature female rainbow trout may have suppressed immune function when sexually mature. Externally, fish appeared to heal at similar rates regardless of the presence or absence of the transmitter, but the tag itself was prone to encapsulation and adhesion to the body wall and/or surgical site. This suggests that fish tagged with large intraperitoneal implants may not behave similarly to their wild counterparts. This research could aid in the development of improved telemetry tags that are more biocompatible, economical and better able to track fish behavior/movement.
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Affiliation(s)
- Shawna L Semple
- Department of Biology, University of Waterloo, 200 University Ave W., Waterloo, ON, N2L 3G1 Canada
| | - Ingeborg M Mulder
- Department of Biology, University of Waterloo, 200 University Ave W., Waterloo, ON, N2L 3G1 Canada
| | - Tania Rodriguez-Ramos
- Department of Biology, University of Waterloo, 200 University Ave W., Waterloo, ON, N2L 3G1 Canada
| | - Michael Power
- Department of Biology, University of Waterloo, 200 University Ave W., Waterloo, ON, N2L 3G1 Canada
| | - Brian Dixon
- Department of Biology, University of Waterloo, 200 University Ave W., Waterloo, ON, N2L 3G1 Canada.
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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: 9] [Impact Index Per Article: 1.5] [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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24
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Stanistreet JE, Nowacek DP, Bell JT, Cholewiak DM, Hildebrand JA, Hodge LEW, Van Parijs SM, Read AJ. Spatial and seasonal patterns in acoustic detections of sperm whales Physeter macrocephalus along the continental slope in the western North Atlantic Ocean. ENDANGER SPECIES RES 2018. [DOI: 10.3354/esr00867] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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25
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Reidenberg JS, Laitman JT. Anatomy of Underwater Sound Production With a Focus on Ultrasonic Vocalization in Toothed Whales Including Dolphins and Porpoises. HANDBOOK OF ULTRASONIC VOCALIZATION - A WINDOW INTO THE EMOTIONAL BRAIN 2018. [DOI: 10.1016/b978-0-12-809600-0.00047-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Lin CF, Chung YC, Zhu JD, Chang SH, Wen CC, Parinov IA, Shevtsov SN. The energy based characteristics of sperm whale clicks using the Hilbert Huang transform analysis method. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2017; 142:504. [PMID: 28863586 DOI: 10.1121/1.4996106] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this paper, a unique analysis method for sperm whale clicks based on Hilbert-Huang transform (HHT) is proposed. Four sperm whale click samples with durations of 10 ms (defined as click I), and four sperm whale click samples with durations of 5 ms (defined as click II) were illustrated. These click samples were recorded in the Mediterranean Sea by Centro Interdisciplinare di Bioacusticae Ricerche Ambientali, Università degli Studi di Pavia. The empirical mode decomposition method was used to decompose click I samples into seven intrinsic mode functions (IMFs) and one residue function (RF), and click II samples were decomposed into six IMFs and one RF. The average energy distributions of multiple IMFs and the single RF domain for click I and click II samples were explored using the HHT analysis method. The average energy-frequency representations were also investigated for the same click I and click II samples. The analysis results show that the energy-frequency characteristics of sperm whale clicks can be extracted and understood by applying several IMFs and one RF signal with a high-resolution analysis.
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Affiliation(s)
- Chin-Feng Lin
- Department of Electrical Engineering, National Taiwan Ocean University, Keelung City, Taiwan
| | - Yao-Ching Chung
- Department of Electrical Engineering, National Taiwan Ocean University, Keelung City, Taiwan
| | - Jin-De Zhu
- Department of Electrical Engineering, National Taiwan Ocean University, Keelung City, Taiwan
| | - Shun-Hsyung Chang
- Department of Microeletronic Engineering, National Kaohsiung Marine University, Kaohsiung City, Taiwan
| | - Chan-Chuan Wen
- Department of Shipping Technology, National Kaohsiung Marine University, Kaohsiung City, Taiwan
| | - Ivan A Parinov
- Vorovich Mechanics and Applied Mathematics Research Institute, Southern Federal University, Rostov Oblast, Russia
| | - S N Shevtsov
- South Scientific Center of Russian Academy of Sciences, Southern Federal District, Russia
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Ladegaard M, Jensen FH, Beedholm K, da Silva VMF, Madsen PT. Amazon river dolphins (Inia geoffrensis) modify biosonar output level and directivity during prey interception in the wild. J Exp Biol 2017; 220:2654-2665. [DOI: 10.1242/jeb.159913] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 05/08/2017] [Indexed: 11/20/2022]
Abstract
Toothed whales have evolved to live in extremely different habitats and yet they all rely strongly on echolocation for finding and catching prey. Such biosonar based foraging involves distinct phases of searching for, approaching, and capturing prey, where echolocating animals gradually adjust sonar output to actively shape the flow of sensory information. Measuring those outputs in absolute levels requires hydrophone arrays centred on the biosonar beam axis, but this has never been done for wild toothed whales approaching and capturing prey. Rather, field studies make the assumption that toothed whales will adjust their biosonar in the same manner to arrays as they will when approaching prey. To test this assumption, we recorded wild botos (Inia geoffrensis) as they approached and captured dead fish tethered to a hydrophone in front of a star-shaped seven-hydrophone array. We demonstrate that botos gradually decrease interclick intervals and output levels during prey approaches, using stronger adjustment magnitudes than extrapolated from previous boto array data. Prey interceptions are characterised by high click rates, but although botos buzz during prey capture, they do so at lower click rates than marine toothed whales, resulting in a much more gradual transition from approach phase to buzzing. We also demonstrate for the first time that wild toothed whales broaden biosonar beamwidth when closing in on prey, as it is also seen in captive toothed whales and in bats, thus resulting in a larger ensonified volume around the prey, likely aiding prey tracking by decreasing the risk of prey evading ensonification.
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Affiliation(s)
- Michael Ladegaard
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
| | | | - Kristian Beedholm
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
| | | | - Peter Teglberg Madsen
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
- Murdoch University Cetacean Research Unit, School of Veterinary and Life Sciences, Murdoch University, South Street, Murdoch, Western Australia 6150, Australia
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Curé C, Isojunno S, Visser F, Wensveen PJ, Sivle LD, Kvadsheim PH, Lam FPA, Miller PJO. Biological significance of sperm whale responses to sonar: comparison with anti-predator responses. ENDANGER SPECIES RES 2016. [DOI: 10.3354/esr00748] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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29
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Fais A, Johnson M, Wilson M, Aguilar Soto N, Madsen PT. Sperm whale predator-prey interactions involve chasing and buzzing, but no acoustic stunning. Sci Rep 2016; 6:28562. [PMID: 27340122 PMCID: PMC4919788 DOI: 10.1038/srep28562] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2015] [Accepted: 06/07/2016] [Indexed: 11/09/2022] Open
Abstract
The sperm whale carries a hypertrophied nose that generates powerful clicks for long-range echolocation. However, it remains a conundrum how this bizarrely shaped apex predator catches its prey. Several hypotheses have been advanced to propose both active and passive means to acquire prey, including acoustic debilitation of prey with very powerful clicks. Here we test these hypotheses by using sound and movement recording tags in a fine-scale study of buzz sequences to relate the acoustic behaviour of sperm whales with changes in acceleration in their head region during prey capture attempts. We show that in the terminal buzz phase, sperm whales reduce inter-click intervals and estimated source levels by 1-2 orders of magnitude. As a result, received levels at the prey are more than an order of magnitude below levels required for debilitation, precluding acoustic stunning to facilitate prey capture. Rather, buzzing involves high-frequency, low amplitude clicks well suited to provide high-resolution biosonar updates during the last stages of capture. The high temporal resolution helps to guide motor patterns during occasionally prolonged chases in which prey are eventually subdued with the aid of fast jaw movements and/or buccal suction as indicated by acceleration transients (jerks) near the end of buzzes.
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Affiliation(s)
- A Fais
- BIOECOMAC. Dept. of Animal Biology, La Laguna University, Spain.,Zoophysiology, Department of Bioscience, Aarhus University, Denmark
| | - M Johnson
- Scottish Ocean Institute, University of St. Andrews, Scotland
| | - M Wilson
- Zoophysiology, Department of Bioscience, Aarhus University, Denmark.,Institute of Biology, University of Southern Denmark, Denmark
| | - N Aguilar Soto
- BIOECOMAC. Dept. of Animal Biology, La Laguna University, Spain.,CREEM, University of St. Andrews, Scotland
| | - P T Madsen
- Zoophysiology, Department of Bioscience, Aarhus University, Denmark.,Murdoch University Cetacean Research Unit, Murdoch University, South Street, Murdoch, Western Australia 6150, Australia
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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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Caruso F, Sciacca V, Bellia G, De Domenico E, Larosa G, Papale E, Pellegrino C, Pulvirenti S, Riccobene G, Simeone F, Speziale F, Viola S, Pavan G. Size Distribution of Sperm Whales Acoustically Identified during Long Term Deep-Sea Monitoring in the Ionian Sea. PLoS One 2015; 10:e0144503. [PMID: 26675588 PMCID: PMC4682957 DOI: 10.1371/journal.pone.0144503] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Accepted: 11/19/2015] [Indexed: 11/18/2022] Open
Abstract
The sperm whale (Physeter macrocephalus) emits a typical short acoustic signal, defined as a "click", almost continuously while diving. It is produced in different time patterns to acoustically explore the environment and communicate with conspecifics. Each emitted click has a multi-pulse structure, resulting from the production of the sound within the sperm whale's head. A Stable Inter Pulse Interval (Stable IPI) can be identified among the pulses that compose a single click. Applying specific algorithms, the measurement of this interval provides useful information to assess the total length of the animal recorded. In January 2005, a cabled hydrophone array was deployed at a depth of 2,100 m in the Central Mediterranean Sea, 25 km offshore Catania (Ionian Sea). The acoustic antenna, named OνDE (Ocean noise Detection Experiment), was in operation until November 2006. OνDE provided real time acoustic data used to perform Passive Acoustic Monitoring (PAM) of cetacean sound emissions. In this work, an innovative approach was applied to automatically measure the Stable IPI of the clicks, performing a cepstrum analysis to the energy (square amplitude) of the signals. About 2,100 five-minute recordings were processed to study the size distribution of the sperm whales detected during the OνDE long term deep-sea acoustic monitoring. Stable IPIs were measured in the range between 2.1 ms and 6.4 ms. The equations of Gordon (1991) and of Growcott (2011) were used to convert the IPIs into measures of size. The results revealed that the sperm whales recorded were distributed in length from about 7.5 m to 14 m. The size category most represented was from 9 m to 12 m (adult females or juvenile males) and specimens longer than 14 m (old males) seemed to be absent.
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Affiliation(s)
- Francesco Caruso
- Dipartimento di Scienze Biologiche e Ambientali, University of Messina, Messina, Italy
- Istituto Nazionale di Fisica Nucleare (INFN)—Laboratori Nazionali del Sud, Catania, Italy
| | - Virginia Sciacca
- Dipartimento di Scienze Biologiche e Ambientali, University of Messina, Messina, Italy
- Istituto Nazionale di Fisica Nucleare (INFN)—Laboratori Nazionali del Sud, Catania, Italy
| | - Giorgio Bellia
- Istituto Nazionale di Fisica Nucleare (INFN)—Laboratori Nazionali del Sud, Catania, Italy
- Dipartimento di Fisica ed Astronomia, University of Catania, Catania, Italy
| | - Emilio De Domenico
- Dipartimento di Scienze Biologiche e Ambientali, University of Messina, Messina, Italy
| | - Giuseppina Larosa
- Istituto Nazionale di Fisica Nucleare (INFN)—Laboratori Nazionali del Sud, Catania, Italy
| | - Elena Papale
- Bioacoustics Lab, IAMC Capo Granitola, National Research Council, Torretta Granitola (TP), Italy
| | - Carmelo Pellegrino
- Istituto Nazionale di Fisica Nucleare (INFN)—Bologna, Bologna, Italy
- Dipartimento di Fisica ed Astronomia, University of Bologna, Bologna, Italy
| | - Sara Pulvirenti
- Istituto Nazionale di Fisica Nucleare (INFN)—Laboratori Nazionali del Sud, Catania, Italy
| | - Giorgio Riccobene
- Istituto Nazionale di Fisica Nucleare (INFN)—Laboratori Nazionali del Sud, Catania, Italy
| | | | - Fabrizio Speziale
- Istituto Nazionale di Fisica Nucleare (INFN)—Laboratori Nazionali del Sud, Catania, Italy
| | - Salvatore Viola
- Istituto Nazionale di Fisica Nucleare (INFN)—Laboratori Nazionali del Sud, Catania, Italy
| | - Gianni Pavan
- Centro Interdisciplinare di Bioacustica e Ricerche Ambientali (CIBRA), Dipartimento di Scienze della Terra e dell’Ambiente, University of Pavia, Pavia, Italy
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32
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Skarsoulis EK, Dosso SE. Linearized two-hydrophone localization of a pulsed acoustic source in the presence of refraction: Theory and simulations. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2015; 138:2221-2234. [PMID: 26520304 DOI: 10.1121/1.4930937] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This paper develops an efficient three-dimensional localization method for transient acoustic sources, with uncertainty estimation, based on time differences between direct and surface-reflected arrivals at two hydrophones. The localization method accounts for refraction caused by a depth-dependent sound-speed profile using a ray-theoretic approach for calculating eigenray travel times and partial derivatives. Further, the method provides localization error estimates accounting for uncertainties of the arrival times and hydrophone locations, as well as for depth-dependent uncertainties in the sound-speed profile. In the first of two steps, source depth and range to each hydrophone are estimated using an iterative, linearized Gauss-Markov inversion scheme. In the second step, the estimated source ranges are combined with the hydrophone locations to obtain the source location in the horizontal. Localization performance is analyzed in a simulation study, and the linearized localization estimates and uncertainties are validated by comparison with a fully nonlinear (but numerically intensive) Markov-chain Monte Carlo inversion.
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Affiliation(s)
- E K Skarsoulis
- Institute of Applied and Computational Mathematics, Foundation for Research and Technology Hellas, GR-711 10 Heraklion, Crete, Greece
| | - Stan E Dosso
- School of Earth and Ocean Sciences, University of Victoria, Victoria, British Columbia V8W 3P6, Canada
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33
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Sperm whale echolocation behaviour reveals a directed, prior-based search strategy informed by prey distribution. Behav Ecol Sociobiol 2015. [DOI: 10.1007/s00265-015-1877-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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34
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A philosophical evaluation of adaptationism as a heuristic strategy. Acta Biotheor 2014; 62:479-98. [PMID: 24992988 DOI: 10.1007/s10441-014-9232-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 06/25/2014] [Indexed: 12/27/2022]
Abstract
Adaptationism has prompted many a debate in philosophy of biology but the focus is usually on empirical and explanatory issues rather than methodological adaptationism (MA). Likewise, the context of evolutionary biology has provided the grounding for most discussions of the heuristic role of adaptationism. This paper extends the debate by drawing on case studies from physiology and systems biology to discuss the productive and problematic aspects of adaptationism in functional as well as evolutionary studies at different levels of biological organization. Gould and Lewontin's Spandrels-paper famously criticized adaptationist methodology for implying a risk of generating 'blind spots' with respect to non-selective effects on evolution. Some have claimed that this bias can be accommodated through the testing of evolutionary hypotheses. Although this is an important aspect of overcoming the pitfalls of adaptationism, I argue that the issue of methodological biases is broader than the question of testability. I demonstrate the productivity of adaptationist heuristics but also discuss the deeper problematic aspects associated with the imperialistic tendencies of the strong account of MA.
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35
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Rogers TL. Source levels of the underwater calls of a male leopard seal. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2014; 136:1495-1498. [PMID: 25324053 DOI: 10.1121/1.4895685] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Leopard seals (Hydrurga leptonyx) are top predators in the Antarctic ecosystem. They produce stereotyped calls as part of a stylized underwater vocal display. Understanding of their acoustic behavior is improved by identifying the amplitude of their calls. The amplitude of five types of calls (n = 50) from a single male seal were measured as broadband source levels and ranged from 153 to 177 dB re 1 μPa at 1 m. The mean source levels differed between call types, the lower frequency calls (L, D, and O) tended to have source levels 10 dB higher than the higher frequency calls (H and M). Information on call-type source levels is important to take into account for passive acoustic studies investigating repertoire usage as calls produced with greater amplitudes are likely to have larger acoustic ranges, especially when these are also the calls with lower frequencies, such as is the case in leopard seals.
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Affiliation(s)
- Tracey L Rogers
- Evolution & Ecology Research Centre, School of BEES, University of New South Wales, Sydney, New South Wales, Australia
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36
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Tran DD, Huang W, Bohn AC, Wang D, Gong Z, Makris NC, Ratilal P. Using a coherent hydrophone array for observing sperm whale range, classification, and shallow-water dive profiles. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2014; 135:3352-3363. [PMID: 24907798 DOI: 10.1121/1.4874601] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Sperm whales in the New England continental shelf and slope were passively localized, in both range and bearing, and classified using a single low-frequency (<2500 Hz), densely sampled, towed horizontal coherent hydrophone array system. Whale bearings were estimated using time-domain beamforming that provided high coherent array gain in sperm whale click signal-to-noise ratio. Whale ranges from the receiver array center were estimated using the moving array triangulation technique from a sequence of whale bearing measurements. Multiple concurrently vocalizing sperm whales, in the far-field of the horizontal receiver array, were distinguished and classified based on their horizontal spatial locations and the inter-pulse intervals of their vocalized click signals. The dive profile was estimated for a sperm whale in the shallow waters of the Gulf of Maine with 160 m water-column depth located close to the array's near-field where depth estimation was feasible by employing time difference of arrival of the direct and multiply reflected click signals received on the horizontal array. By accounting for transmission loss modeled using an ocean waveguide-acoustic propagation model, the sperm whale detection range was found to exceed 60 km in low to moderate sea state conditions after coherent array processing.
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Affiliation(s)
- Duong D Tran
- Department of Electrical and Computer Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115
| | - Wei Huang
- Department of Electrical and Computer Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115
| | - Alexander C Bohn
- Department of Electrical and Computer Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115
| | - Delin Wang
- Department of Electrical and Computer Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115
| | - Zheng Gong
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139
| | - Nicholas C Makris
- Department of Mechanical Engineering, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139
| | - Purnima Ratilal
- Department of Electrical and Computer Engineering, Northeastern University, 360 Huntington Avenue, Boston, Massachusetts 02115
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37
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Goldbogen JA, Meir JU. The device that revolutionized marine organismal biology. J Exp Biol 2014; 217:167-8. [DOI: 10.1242/jeb.092189] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
| | - Jessica U. Meir
- NASA Johnson Space Center and Harvard, Medical School/Massachusetts General Hospital,
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38
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Fenton B, Jensen FH, Kalko EKV, Tyack PL. Sonar Signals of Bats and Toothed Whales. BIOSONAR 2014. [DOI: 10.1007/978-1-4614-9146-0_2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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39
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40
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Tracking Technologies for Quantifying Marine Mammal Interactions with Tidal Turbines: Pitfalls and Possibilities. MARINE RENEWABLE ENERGY TECHNOLOGY AND ENVIRONMENTAL INTERACTIONS 2014. [DOI: 10.1007/978-94-017-8002-5_10] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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41
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Azzara AJ, von Zharen WM, Newcomb JJ. Mixed-methods analytic approach for determining potential impacts of vessel noise on sperm whale click behavior. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2013; 134:4566. [PMID: 25669266 DOI: 10.1121/1.4828819] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The Gulf of Mexico is a center of marine activities from seismic exploration to shipping, drilling, platform installation, lightering, and construction, among others. This analysis explored whether sperm whales respond to the passage of vessels using changes in total number of clicks during vessel passages as a proxy for potential variation in behavior. The data for this analysis were collected in 2001 as part of a larger Littoral Acoustic Demonstration Center project using the Environmental Acoustics Recording System buoys. These buoys were bottom moored, autonomous, and self-recording systems consisting of an omni-directional hydrophone and instrument package. Data from 36 days of continuous acoustic monitoring were recorded at a sampling rate of 11.725 kHz, and produced reliable recordings from 5 Hz to ∼5.8 kHz. Multiple preparatory steps were executed including calibration of an automatic click detector. Results indicate a significant decrease (32%) in the number of clicks detected as a ship approached an area. There were also significantly fewer clicks detected after the vessel passed than before (23%).
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Affiliation(s)
- Alyson J Azzara
- Department of Marine Sciences, Texas A&M University at Galveston, Galveston, Texas 77553
| | - Wyndylyn M von Zharen
- Department of Marine Sciences, Texas A&M University at Galveston, Galveston, Texas 77553
| | - Joal J Newcomb
- Naval Oceanographic Office, John C. Stennis Space Center, Stennis Space Center, Mississippi 39522
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42
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Huggenberger S, André M, Oelschläger HHA. An acoustic valve within the nose of sperm whales Physeter macrocephalus. Mamm Rev 2013. [DOI: 10.1111/mam.12017] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Stefan Huggenberger
- Cologne Biocentre; University of Cologne; Cologne 50923 Germany
- Department II of Anatomy; University of Cologne; Cologne 50924 Germany
| | - Michel André
- Laboratori d'Aplicacions Bioacústiques; Universitat Politècnica de Catalunya; Centre Tecnològic de Vilanova i la Geltrú, Avenida.Rambla Exposició, s/n, Vilanova i la Geltrú Barcelona 08800 Spain
| | - Helmut H. A. Oelschläger
- Department of Anatomy III (Dr. Senckenbergische Anatomie); Johann Wolfgang Goethe University Frankfurt am Main; Frankfurt am Main 60590 Germany
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Abstract
Many articles in this section of Comprehensive Physiology are concerned with the development and function of a central pattern generator (CPG) for the control of breathing in vertebrate animals. The action of the respiratory CPG is extensively modified by cortical and other descending influences as well as by feedback from peripheral sensory systems. The central nervous system also incorporates other CPGs, which orchestrate a wide variety of discrete and repetitive, voluntary and involuntary movements. The coordination of breathing with these other activities requires interaction and coordination between the respiratory CPG and those governing the nonrespiratory activities. Most of these interactions are complex and poorly understood. They seem to involve both conventional synaptic crosstalk between groups of neurons and fluid identity of neurons as belonging to one CPG or another: neurons that normally participate in breathing may be temporarily borrowed or hijacked by a competing or interrupting activity. This review explores the control of breathing as it is influenced by many activities that are generally considered to be nonrespiratory. The mechanistic detail varies greatly among topics, reflecting the wide variety of pertinent experiments.
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Affiliation(s)
- Donald Bartlett
- Department of Physiology & Neurobiology, Dartmouth Medical School, Lebanon, New Hampshire, USA.
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Madsen PT, Lammers M, Wisniewska D, Beedholm K. Nasal sound production in echolocating delphinids (Tursiops truncatus and Pseudorca crassidens) is dynamic, but unilateral: clicking on the right side and whistling on the left side. J Exp Biol 2013; 216:4091-102. [DOI: 10.1242/jeb.091306] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
SUMMARY
Toothed whales produce sound in their nasal complex by pneumatic actuation of phonic lip pairs within the blowhole. It has been hypothesized that dual actuation of the phonic lip pairs can generate two pulses that merge to form a single echolocation click with a higher source level, broader bandwidth and larger potential for beam steering than if produced by a single pair of phonic lips. Here, we test that hypothesis by measuring the sound production of five echolocating delphinids using hydrophones around the animals and imbedded in on-animal suction cups. We show that the studied animals click with their right pair of phonic lips and whistle with their left pair. We demonstrate that, with just a single pair of phonic lips, they can change the click energy levels over five orders of magnitude, change the click centroid frequencies over more than two octaves, and modulate the sound radiation from the melon for beam steering. We conclude that all of the click dynamics ascribed to dual actuation of two phonic lip pairs can be achieved with actuation of just the right pair of phonic lips, and we propose that the large dynamic range of source outputs is achieved by highly controlled modulation of the pneumatic driving pressure, the tension of the phonic lip labia and the conformation of the fatty melon and associated air sacs.
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Affiliation(s)
- Peter T. Madsen
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
| | - Marc Lammers
- Marine Mammal Research Program, Hawaii Institute of Marine Biology, Kailua, HI 96734, USA
| | - Danuta Wisniewska
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
| | - Kristian Beedholm
- Zoophysiology, Department of Bioscience, Aarhus University, 8000 Aarhus, Denmark
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Curé C, Antunes R, Alves AC, Visser F, Kvadsheim PH, Miller PJO. Responses of male sperm whales (Physeter macrocephalus) to killer whale sounds: implications for anti-predator strategies. Sci Rep 2013; 3:1579. [PMID: 23545484 PMCID: PMC3613802 DOI: 10.1038/srep01579] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2012] [Accepted: 02/28/2013] [Indexed: 11/15/2022] Open
Abstract
Interactions between individuals of different cetacean species are often observed in the wild. Killer whales (Orcinus orca) can be potential predators of many other cetaceans, and the interception of their vocalizations by unintended cetacean receivers may trigger anti-predator behavior that could mediate predator-prey interactions. We explored the anti-predator behaviour of five typically-solitary male sperm whales (Physeter macrocephalus) in the Norwegian Sea by playing sounds of mammal-feeding killer whales and monitoring behavioural responses using multi-sensor tags. Our results suggest that, rather than taking advantage of their large aerobic capacities to dive away from the perceived predator, sperm whales responded to killer whale playbacks by interrupting their foraging or resting dives and returning to the surface, changing their vocal production, and initiating a surprising degree of social behaviour in these mostly solitary animals. Thus, the interception of predator vocalizations by male sperm whales disrupted functional behaviours and mediated previously unrecognized anti-predator responses.
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Affiliation(s)
- Charlotte Curé
- Sea Mammal Research Unit, School of Biology, University of St. Andrews, Fife KY16 8LB, St. Andrews, UK. )
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Nakamura G, Zenitani R, Kato H. Relative Skull Growth of the Sperm Whale,Physeter macrocephalus, with a Note of Sexual Dimorphism. MAMMAL STUDY 2013. [DOI: 10.3106/041.038.0306] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Madsen PT, de Soto NA, Arranz P, Johnson M. Echolocation in Blainville’s beaked whales (Mesoplodon densirostris). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2013; 199:451-69. [DOI: 10.1007/s00359-013-0824-8] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Accepted: 04/20/2013] [Indexed: 10/26/2022]
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Oliveira C, Wahlberg M, Johnson M, Miller PJO, Madsen PT. The function of male sperm whale slow clicks in a high latitude habitat: communication, echolocation, or prey debilitation? THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2013; 133:3135-3144. [PMID: 23654416 DOI: 10.1121/1.4795798] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Sperm whales produce different click types for echolocation and communication. Usual clicks and buzzes appear to be used primarily in foraging while codas are thought to function in social communication. The function of slow clicks is less clear, but they appear to be produced by males at higher latitudes, where they primarily forage solitarily, and on the breeding grounds, where they roam between groups of females. Here the behavioral context in which these vocalizations are produced and the function they may serve was investigated. Ninety-nine hours of acoustic and diving data were analyzed from sound recording tags on six male sperm whales in Northern Norway. The 755 slow clicks detected were produced by tagged animals at the surface (52%), ascending from a dive (37%), and during the bottom phase (11%), but never during the descent. Slow clicks were not associated with the production of buzzes, other echolocation clicks, or fast maneuvering that would indicate foraging. Some slow clicks were emitted in seemingly repetitive temporal patterns supporting the hypothesis that the function for slow clicks on the feeding grounds is long range communication between males, possibly relaying information about individual identity or behavioral states.
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Affiliation(s)
- Cláudia Oliveira
- Departamento de Oceanografia e Pescas e Instituto do Mar- Universidade dos Açores, Horta, Açores, Portugal.
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Jensen FH, Rocco A, Mansur RM, Smith BD, Janik VM, Madsen PT. Clicking in shallow rivers: short-range echolocation of Irrawaddy and Ganges River dolphins in a shallow, acoustically complex habitat. PLoS One 2013; 8:e59284. [PMID: 23573197 PMCID: PMC3616034 DOI: 10.1371/journal.pone.0059284] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 02/13/2013] [Indexed: 11/26/2022] Open
Abstract
Toothed whales (Cetacea, odontoceti) use biosonar to navigate their environment and to find and catch prey. All studied toothed whale species have evolved highly directional, high-amplitude ultrasonic clicks suited for long-range echolocation of prey in open water. Little is known about the biosonar signals of toothed whale species inhabiting freshwater habitats such as endangered river dolphins. To address the evolutionary pressures shaping the echolocation signal parameters of non-marine toothed whales, we investigated the biosonar source parameters of Ganges river dolphins (Platanista gangetica gangetica) and Irrawaddy dolphins (Orcaella brevirostris) within the river systems of the Sundarban mangrove forest. Both Ganges and Irrawaddy dolphins produced echolocation clicks with a high repetition rate and low source level compared to marine species. Irrawaddy dolphins, inhabiting coastal and riverine habitats, produced a mean source level of 195 dB (max 203 dB) re 1 µPapp whereas Ganges river dolphins, living exclusively upriver, produced a mean source level of 184 dB (max 191) re 1 µPapp. These source levels are 1–2 orders of magnitude lower than those of similar sized marine delphinids and may reflect an adaptation to a shallow, acoustically complex freshwater habitat with high reverberation and acoustic clutter. The centroid frequency of Ganges river dolphin clicks are an octave lower than predicted from scaling, but with an estimated beamwidth comparable to that of porpoises. The unique bony maxillary crests found in the Platanista forehead may help achieve a higher directionality than expected using clicks nearly an octave lower than similar sized odontocetes.
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Affiliation(s)
- Frants H Jensen
- Department of Biology, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, United States of America.
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Johnson M, Partan J, Hurst T. Low complexity lossless compression of underwater sound recordings. THE JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA 2013; 133:1387-1398. [PMID: 23464010 DOI: 10.1121/1.4776206] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Autonomous listening devices are increasingly used to study vocal aquatic animals, and there is a constant need to record longer or with greater bandwidth, requiring efficient use of memory and battery power. Real-time compression of sound has the potential to extend recording durations and bandwidths at the expense of increased processing operations and therefore power consumption. Whereas lossy methods such as MP3 introduce undesirable artifacts, lossless compression algorithms (e.g., flac) guarantee exact data recovery. But these algorithms are relatively complex due to the wide variety of signals they are designed to compress. A simpler lossless algorithm is shown here to provide compression factors of three or more for underwater sound recordings over a range of noise environments. The compressor was evaluated using samples from drifting and animal-borne sound recorders with sampling rates of 16-240 kHz. It achieves >87% of the compression of more-complex methods but requires about 1/10 of the processing operations resulting in less than 1 mW power consumption at a sampling rate of 192 kHz on a low-power microprocessor. The potential to triple recording duration with a minor increase in power consumption and no loss in sound quality may be especially valuable for battery-limited tags and robotic vehicles.
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Affiliation(s)
- Mark Johnson
- Scottish Oceans Institute, University of St. Andrews, Fife KY16 8LB, United Kingdom.
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