Whale vocalizations are the sounds made by whales to communicate. The word "song" is used in particular to describe the pattern of regular and predictable sounds made by some species of whales (notably the humpback and bowhead whales) in a way that is reminiscent of human singing.
Humans produce sound by expelling air through the larynx. The vocal cords within the larynx open and close as necessary to separate the stream of air into discrete pockets of air. These pockets are shaped by the throat, tongue, and lips into the desired sound.
Cetacean sound production differs markedly from this mechanism. The precise mechanism differs in the two major suborders of cetaceans: the Odontoceti (toothed whales—including dolphins) and the Mysticeti (baleen whales—including the largest whales, such as the blue whale).
Blue whale (Balaenoptera musculus)
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Estimates made by Cummings and Thompson (1971)[1] and Richardson et al. (1995)[2] suggest that source level of sounds made by blue whales are between 155 and 188 decibels with reference to one micropascal metre. All blue whale groups make calls at a fundamental frequency of between 10 and 40 Hz, and the lowest frequency sound a human can typically perceive is 20 Hz. Blue whale calls last between ten and thirty seconds. Additionally blue whales off the coast of Sri Lanka have been recorded repeatedly making "songs" of four notes duration lasting about two minutes each, reminiscent of the well-known humpback whale songs.
All of the baleen whale sound files on this page (with the exception of the humpback vocalizations) are reproduced at 10x speed to bring the sound into the human auditory band.
Vocalizations produced by the Eastern North Pacific population have been well studied. This population produces long-duration, low frequency pulses ("A") and tonal calls ("B"), upswept tones that precede type B calls ("C"), moderate-duration downswept tones ("D"), and variable amplitude-modulated and frequency-modulated sounds.[3][4][5][6] A and B calls are often produced in repeated co-occurring sequences as song only by males, suggesting a reproductive function.[6][7] D calls are produced by both sexes during social interactions while foraging and may considered multi-purpose contact calls.[7][8][9] Because the calls have also been recorded from blue whale trios from in a putative reproductive context, it has been recently suggested that this call has different functions.[10] The blue whale call recorded off Sri Lanka is a three‐unit phrase. The first unit is a pulsive call ranging 19.8 to 43.5 Hz, lasting 17.9 ± 5.2 s. The second unit is an FM upsweep 55.9 to 72.4 Hz lasting 13.8 ± 1.1 s. The final unit is a long (28.5 ± 1.6 s) tone that sweeps from 108 to 104.7 Hz.[11] The blue whale call recorded off Madagascar, a two‐unit phrase,[12] starts with 5–7 pulses with a center frequency of 35.1 ± 0.7 Hz and duration of 4.4 ± 0.5 s followed by a 35 ± 0 Hz tone lasting 10.9 ± 1.1 s.[11] In the Southern Ocean, blue whales calls last roughly 18 seconds and consist of a 9-s-long, 27 Hz tone, followed by a 1-s downsweep to 19 Hz, and another downsweep to 18 Hz.[13][14] They also produce short, 1–4 s duration, frequency-modulated calls ranging in frequency between 80 and 38 Hz.[14][15]
At least seven blue whale song types have been shifting linearly downward in tonal frequency over time, though at different rates.[16][17][18]
The Eastern North Pacific blue whale tonal frequency is 31% lower than it was in the early 1960s.[16][17] The frequency of pygmy blue whales in the Antarctic has steadily decreased at a rate of a few tenths of hertz per year since 2002.[18] One hypothesis is that as blue whale populations recover from whaling, this is increasing sexual selection pressure (i.e., lower frequency indicates larger body size).[17]
Fin whale (Balaenoptera physalus)
editLike other whales, the male fin whale has been observed to make long, loud, low-frequency sounds.[19] Most sounds are frequency-modulated (FM) down-swept infrasonic pulses from 16 to 40 hertz frequency (the range of sounds that most humans can hear falls between 20 hertz and 20 kilohertz). Each sound lasts between one and two seconds, and various combinations of sounds occur in patterned sequences lasting 7 to 15 minutes each. These sequences are then repeated in bouts lasting up to many days.[20]
Bowhead whale (Balaena mysticetus)
editBowhead whales are highly vocal[21] and use low frequency (<1000 Hz) sounds to communicate while travelling, feeding, and socialising. Intense calls for communication and navigation are produced especially during migration season. During breeding season, bowheads make long, complex, variable songs for mating calls.[22] Many tens of distinct songs are sung by a population in a single season.[23] From 2010 through to 2014, near Greenland, 184 distinct songs were recorded from a population of around 300 animals.[24]
Humpback whale (Megaptera novaeangliae)
editThe humpback whale is well known for its long and complex song. Humpbacks repeat patterns of low notes that vary in amplitude and frequency in consistent patterns over a period of hours or even days. Only male humpbacks sing, so it was at first assumed that the songs were solely for courting. While the primary purpose of whale song may be to attract females, it is almost certain that whale song serves myriad purposes.
Orca (killer whale) (Orcinus orca)
editLike other delphinids, orcas are very vocal animals. They produce a variety of clicks and pulsed calls that are used for echolocation and communication.
Much of the time, resident orcas in the northeast Pacific are more vocal than Bigg's (transient) orcas living in the same waters. Scientists believe that the main reason for this lies in the different hearing abilities of their prey. Resident orcas feed on fish, mostly Pacific salmon, a prey with poor underwater hearing that cannot detect orca sounds at any great distance. Transient orcas on the other hand feed mainly on marine mammals, primarily seals, sea lions, and porpoises. Because all marine mammals have excellent underwater hearing, transients probably remain silent until they have caught their prey to avoid detection by acoustically sensitive animals. For the same reason, the mammal-eating orcas tend to restrict their echolocation, occasionally using just a single click (called a cryptic click) rather than the long train of clicks heard in the fish–eating ecotype.
Minke whale (Balaenoptera spp.)
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References
edit- ^ W.C. Cummings & P.O. Thompson (1971). "Underwater sounds from the blue whale Balaenoptera musculus". Journal of the Acoustical Society of America. 50 (4): 1193–1198. doi:10.1121/1.1912752.
- ^ W.J. Richardson; C.R. Greene; C.I. Malme; D.H. Thomson (1995). Marine mammals and noise. Academic Press, Inc., San Diego, CA. ISBN 0-12-588441-9.
- ^ Thompson, P. O.; Findley, L. T.; Vidal, O.; Cummings, W. C.; et al. (1996). "Underwater sounds of blue whales, Balaenoptera musculus, in the Gulf of California, Mexico". Marine Mammal Science. 13 (2): 288–293. doi:10.1111/j.1748-7692.1996.tb00578.x.
- ^ Aroyan, J. L.; McDonald, M. A.; Webb, S. C.; Hildebrand, J. A.; Clark, D. S.; Laitman, J. T.; Reidenberg, J. S. (2000). "Acoustic models of sound production and propagation". In Au, W. W. A.; Popper, A.; Fay, R. N. (eds.). Hearing by whales and dolphins. New York: Springer-Verlag. pp. 409–469.
- ^ Thode, A. M.; D'Spain, G. L.; Kuperman, W. A. (2000). "Matched-field processing, geoacoustic inversion, and source signature recovery of blue whale vocalizations". Journal of the Acoustical Society of America. 107 (3): 1286–1300. Bibcode:2000ASAJ..107.1286T. doi:10.1121/1.428417. PMID 10738784. S2CID 25361396.
- ^ a b McDonald, M. A.; Calambokidis, J.; Teranishi, A. M.; Hildebrand, J. A. (2001). "The acoustic calls of blue whales off California with gender data". Journal of the Acoustical Society of America. 109 (4): 1728–1735. Bibcode:2001ASAJ..109.1728M. doi:10.1121/1.1353593. PMID 11325141.
- ^ a b Oleson, E. M.; Calambokidis, J.; Burgess, W. C.; McDonald, M. A.; LeDuc, C. A.; Hildebrand, J. A. (2007). "Behavioral context of call production by eastern North Pacific blue whales". Marine Ecology Progress Series. 330: 269–284. Bibcode:2007MEPS..330..269O. doi:10.3354/meps330269.
- ^ Oleson, E. M.; Calambokidis, J.; Barlow, J.; Hildebrand, J. A. (2007). "Blue whale visual and acoustic encounter rates in the Southern California Bight". Marine Mammal Science. 23 (3): 574–597. doi:10.1111/j.1748-7692.2007.02303.x. S2CID 7335728.
- ^ Lewis, L. A.; Calambokidis, J.; Stimpert, A. K.; Fahlbusch, J.; Friedlaender, A. S.; McKenna, M. F.; Mesnick, S.; Oleson, E. M.; Southall, B. L.; Szesciorka, A. S.; Sirovic, A. (2018). "Context-dependent variability in blue whale acoustic behaviour". Royal Society Open Science. 5 (8): 1080241. doi:10.1098/rsos.180241. PMC 6124089. PMID 30225013.
- ^ Schall, E.; Di Lorio, L.; Berchok, C.; Filún, D.; Bedriñana-Romano, L.; Buchan, S. J.; Van Opzeeland, I.; Sears, R.; Hucke-Gaete, R. (2019). "Visual and passive acoustic observations of blue whale trios from two distinct populations". Marine Mammal Science. 36 (1): 365–374. doi:10.1111/mms.12643. hdl:1912/24953.
- ^ a b Stafford, K. M.; Chapp, E.; Bohnenstiel, D.; Tolstoy, M. (2010). "Seasonal detection of three types of "pygmy" blue whale calls in the Indian Ocean". Marine Mammal Science. 27 (4): 828–840. doi:10.1111/j.1748-7692.2010.00437.x.
- ^ Ljungblad, D. K.; Clark, C. W.; Shimada, H. (1998). A comparison of sounds attributed to pygmy blue whales (Balaenoptera musculus brevicauda) recorded south of the Madagascar Plateau and those attributed to 'true' blue whales (Balaenoptera musculus) recorded off Antarctica (Report). Vol. 48. International Whaling Commission. pp. 439–442.
- ^ Sirovic, A.; Hildebrand, J. A.; Wiggins, S. M.; McDonald, M. A.; Moore, S. E.; Thiele, D. (2004). "Seasonality of blue and fin whale calls and the influence of sea ice in the Western Antarctic Peninsula". Deep Sea Research Part II: Topical Studies in Oceanography. 51 (17–19): 2327–2344. Bibcode:2004DSRII..51.2327S. doi:10.1016/j.dsr2.2004.08.005.
- ^ a b Rankin, S.; Ljungblad, D.; Clark, C.; Kato, H. (2023). "Vocalisations of Antarctic blue whales, Balaenoptera musculus intermedia, recorded during the 2001/2002 and 2002/2003 IWC/SOWER circumpolar cruises, Area V, Antarctica". Journal of Cetacean Research and Management. 7: 13–20. doi:10.47536/jcrm.v7i1.752. S2CID 43993242.
- ^ Sirovic, A.; Hildebrand, J. A.; Thiele, D. (2006). "Baleen whales in the Scotia Sea in January and February 2003". Journal of Cetacean Research and Management. 8: 161–171. doi:10.47536/jcrm.v8i2.712. S2CID 251277044.
- ^ a b Nieukirk, S. L.; Mellinger, D. K.; Hildebrand, J. A.; McDonald, M. A.; Dziak, R. P. (2005). Downward shift in the frequency of blue whale vocalizations. 16th Biennial Conference on the Biology of Marine Mammals. San Diego, CA. p. 205.
- ^ a b c McDonald, M. A.; Hildebrand, J. A.; Mesnick, S. (2009). "Worldwide decline in tonal frequencies of blue whale songs". Endangered Species Research. 9: 13–21. doi:10.3354/esr00217.
- ^ a b Leroy, E. C.; Royer, J.-Y.; Bonnel, J.; Samaran, F. (2018). "Long-term and seasonal changes of large whale call frequency in the southern Indian Ocean". Journal of Geophysical Research: Oceans. 123 (11): 8568–8580. Bibcode:2018JGRC..123.8568L. doi:10.1029/2018JC014352. hdl:1912/10837. S2CID 135201588.
- ^ Fox, David (2001). "Balaenoptera physalus (fin whale)". Animal Diversity Web. Retrieved 2006-10-22.
- ^ "Finback Whale Vocalizations". Bioacoustics Research Program, Cornell Lab of Ornithology. Archived from the original on 2006-10-05. Retrieved 2006-10-26.
- ^ "Bowhead Whale : Baleen Whales : Voices in the Sea". Archived from the original on 21 September 2013. Retrieved 3 April 2013.
- ^ Finley, K.J. (2001). "Natural History and Conservation of the Greenland Whale, or Bowhead, in the Northeast Atlantic" (PDF). Arctic. 54 (1): 55–76. CiteSeerX 10.1.1.500.2600. doi:10.14430/arctic764.
- ^ "SAFS Seminar: Kate Stafford, Scientific serendipity—unveiling the acoustic behavior of bowhead whales". University of Washington. Retrieved January 14, 2024.
- ^ Micu, Alexandru (2018-04-05). ""Bowhead [whales] are jazz," says researcher astonished by the diversity of their songs". ZME Science. Retrieved 2018-04-05.