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{{Short description|Baleen whale, largest animal ever known}}
{{Taxobox
{{Other uses}}
| name = '''Blue whale'''<ref name=msw3>{{MSW3 Mead
{{Pp|small=yes}}
| pages = 725}}</ref>
{{Pp-move}}
{{Featured article}}
{{Use American English|date=February 2022}}
{{Use dmy dates|date=January 2023}}
{{Speciesbox
| fossil_range = ] – Recent {{fossil range|1.5|0}}
| status = EN | status = EN
| status_system = iucn3.1 | status_system = IUCN3.1
| status_ref =<ref name="iucn">{{cite iucn |author=Cooke, J.G. |year=2018 |errata=2019 |title=''Balaenoptera musculus'' |volume=2018 |page=e.T2477A156923585 |doi=10.2305/IUCN.UK.2018-2.RLTS.T2477A156923585.en |access-date=13 June 2024}}</ref>
| status_ref =<ref name="iucn">{{IUCN2008
| status2 = CITES_A1
|assessors=Reilly, S.B., Bannister, J.L., Best, P.B., Brown, M., Brownell Jr., R.L., Butterworth, D.S., Clapham, P.J., Cooke, J., Donovan, G.P., Urbán, J. & Zerbini, A.N.
| status2_system = CITES
|year=2008
| status2_ref = <ref>{{cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php|access-date=14 January 2022|website=cites.org}}</ref>
|id=2477
| image = Anim1754 - Flickr - NOAA Photo Library.jpg
|title=Balaenoptera musculus
| image_caption = {{longitem|Adult blue whale <br />(''Balaenoptera musculus'')}}
|downloaded=7 October 2008}}</ref>
| image2 = blue whale size.svg
| image = Bluewhale877.jpg
| image2_caption = {{longitem|Size compared to an average human}}
| image_caption = Adult blue whale from the eastern Pacific Ocean
| genus = Balaenoptera
| image2 = Blue_whale_size.svg
| species = musculus
| image2_caption = Size comparison against an average human
| authority = (], ])
| regnum = ]ia
| subdivision_ranks = Subspecies
| phylum = ]
| classis = ]ia
| ordo = ]
| subordo = ]
| familia = ]
| genus = '']''
| species = '''''B. musculus '''''
| binomial = ''Balaenoptera musculus''
| binomial_authority = (], 1758)
| subdivision_ranks = ]
| subdivision = | subdivision =
*'']'' <small>Ichihara, 1966</small> * '']'' <small>Ichihara, 1966</small>
*?''B. m. indica'' <small>Blyth, 1859</small> * ?''B. m. indica'' <small>Blyth, 1859</small>
*''B. m. intermedia'' <small>Burmeister, 1871</small> * ''B. m. intermedia'' <small>Burmeister, 1871</small>
*''B. m. musculus'' <small>Linnaeus, 1758</small> * ''B. m. musculus'' <small>Linnaeus, 1758</small>
| range_map = cetacea_range_map_Blue_Whale.PNG | range_map = Cypron-Range Balaenoptera musculus.svg
| range_map_caption = Blue whale range (in blue) | range_map_caption = Blue whale range (in blue)
| synonyms =
* ''Balaena musculus'' {{small|Linnaeus, 1758}}
* ''Balaenoptera gibbar'' <small>] 1820</small>
* ''Pterobalaena gigas'' <small>] 1861</small>
* ''Physalus latirostris'' <small>] 1864</small>
* ''Sibbaldius borealis'' <small>] 1866</small>
* ''Flowerius gigas'' <small>] 1867</small>
* ''Sibbaldius sulfureus'' <small>] 1869</small>
* ''Balaenoptera sibbaldii'' <small>] 1875</small>
}} }}


The '''blue whale''' ('''''Balaenoptera musculus''''') is a ] and a ]. Reaching a maximum confirmed length of {{cvt|29.9|m}} and weighing up to {{cvt|199|t|sp=}}, it is the ].{{efn|The extinct whale species ''] colossus'' (described in 2023) has been suggested as a potential contender of the blue whale in size,<ref name="AT23">{{cite journal|last1=Bianucci|first1=G.|last2=Lambert|first2=O.|last3=Urbina|first3=M.|last4=Merella|first4=M.|last5=Collareta|first5=A.|last6=Bennion|first6=R.|last7=Salas-Gismondi|first7=R.|last8=Benites-Palomino|first8=A.|last9=Post|first9=K.|last10=de Muizon|first10=C.|last11=Bosio|first11=G.|last12=Di Celma|first12=C.|last13=Malinverno|first13=E.|last14=Pierantoni|first14=P.P.|last15=Villa|first15=I.M.|last16=Amson|first16=E.| year=2023|title=A heavyweight early whale pushes the boundaries of vertebrate morphology|journal=Nature|volume=620 |issue=7975 |pages=824–829 |doi=10.1038/s41586-023-06381-1|pmid=37532931 |bibcode=2023Natur.620..824B |s2cid=260433513 }}</ref> however, this was later disputed in 2024.<ref name=MP24/> Several extinct dinosaurs may also have reached a similar mass to the blue whale.<ref name="Bruhathkayosaurus2023"/>}} The blue whale's long and slender body can be of various shades of greyish-blue on its upper surface and somewhat lighter underneath. Four ] are recognized: ''B. m. musculus'' in the North Atlantic and North Pacific, ''B. m. intermedia'' in the Southern Ocean, ''B. m. brevicauda'' (the ]) in the Indian Ocean and South Pacific Ocean, and ''B. m. indica'' in the Northern Indian Ocean. There is a population in the waters off Chile that may constitute a fifth subspecies.
The '''Blue whale''' ('''''Balaenoptera musculus''''') is a ] belonging to the suborder of ]s (called ]).<ref name="factsheet" /> At over {{convert|33|m|ft}} in length and {{convert|180|metric ton|short ton|lk=on}}<ref>{{Cite web
| url=http://nationalzoo.si.edu/Animals/AnimalRecords/
| title=Animal Records
| publisher=Smithsonian National Zoological Park
| accessdate=2007-05-29 }}</ref> or more in weight, it is the ] ever known to have existed.<ref>{{cite web
| url=http://science.howstuffworks.com/question687.htm
| title=What is the biggest animal ever to exist on Earth?
| publisher=How Stuff Works
| accessdate=2007-05-29}}</ref>


In general, blue whale populations migrate between their summer feeding areas near the poles and their winter breeding grounds near the tropics. There is also evidence of year-round residencies, and partial or age/sex-based migration. Blue whales are ]s; their diet consists almost exclusively of ]. They are generally solitary or gather in small groups, and have no well-defined social structure other than mother–calf bonds. Blue whales vocalize, with a ] ranging from 8 to 25&nbsp;Hz; their vocalizations may vary by region, season, behavior, and time of day. ]s are their only natural predators.
Long and slender, the blue whale's body can be various shades of bluish-grey dorsally and somewhat lighter underneath.<ref> Fisheries and Aquaculture Department, Food and Agriculture Organization.</ref> There are at least three distinct ]: ''B. m. musculus'' of the North Atlantic and North Pacific, ''B. m. intermedia'' of the ] and ''B. m. brevicauda'' (also known as the ]) found in the ] and ]. ''B. m. indica'', found in the Indian Ocean, may be another subspecies. As with other baleen whales, its diet consists almost exclusively of small ]s known as ].<ref name="wheelock">{{cite web
|url=http://whale.wheelock.edu/bwcontaminants/welcome.html
|title=Contaminant analysis of organochlorines in blubber biopsies from blue whales in the St Lawrence
|publisher=Trent University
|author=Jason de Koning and Geoff Wild
|year=1997
| accessdate = 2007-06-29}}</ref>


The blue whale was ] until the end of the 19th&nbsp;century. It was hunted almost to the point of extinction by ] until the ] banned all blue whale hunting in 1966. The ] has listed blue whales as ] as of 2018. It continues to face numerous man-made threats such as ], ], ], and ]. Scientists found evidence of this through morphological or epidemiological analysis. These analyses are accompanied by chemical profiles that use fecal and tissue which continue to prove the impact of man-made threats.
Blue whales were abundant in nearly all the oceans until the beginning of the twentieth century. For over 40 years, they were hunted almost to ] by ] until protected by the international community in 1966. A 2002 report estimated there were 5,000 to 12,000 blue whales worldwide<ref name=pop>{{cite web
|url=http://www.sararegistry.gc.ca/virtual_sara/files/cosewic/sr_blue_whale_e.pdf
|publisher=Committee on the Status of Endangered Wildlife in Canada
|year=2002
|title=Assessment and Update Status Report on the Blue Whale ''Balaenoptera musculus''
| accessdate = 2007-04-19
|format=PDF}}</ref>, located in at least five groups. More recent research into the Pygmy subspecies suggests this may be an underestimate.<ref name=BBC_pop>{{Cite web
| author=Alex Kirby|work= BBC News
| title=Science seeks clues to pygmy whale
| url=http://news.bbc.co.uk/2/hi/science/nature/3003564.stm
| accessdate=April 21, 2006 | date=2003-06-19}}</ref> Before whaling, the largest population was in the Antarctic, numbering approximately 239,000 (range 202,000 to 311,000).<ref name = Ant>{{cite journal
| title = Evidence for increases in Antarctic blue whales based on Bayesian modelling
| author = T.A. Branch, K. Matsuoka and T. Miyashita
| journal = Marine Mammal Science
| volume = 20
| pages = 726–754
|year = 2004
| doi = 10.1111/j.1748-7692.2004.tb01190.x}}</ref> There remain only much smaller (around 2,000) concentrations in each of the North-East ], ], and ] groups. There are two more groups in the North ], and at least two in the ].


==Taxonomy== == Taxonomy ==
{{See also|Evolution of cetaceans}} {{See also|Evolution of cetaceans}}
Blue whales are ] (family ]), a family that includes the ], the ], ], the ] and the ].<ref name="factsheet" /> The family ] is believed to have diverged from the other families of the suborder ] as long ago as the middle ]. However, it is not known when the members of those families diverged from each other.


=== Nomenclature ===
The blue whale is usually classified as one of eight species in the genus ''Balaenoptera''; one authority places it in a separate monotypic genus, ''Sibbaldus'',<ref>{{cite book
The genus name, '']'', means ''winged whale,''<ref name=Reeves_etal_2002/> while the species name, ''musculus'', could mean "muscle" or a diminutive form of "mouse", possibly a pun by ]<ref name=Reeves_etal_2002/><ref name=Calamb_Steig_1997/> when he named the species in '']''.<ref name=Linnaeus_1758>{{cite book | last=Linnaeus | first=Carl | date=1758 | title=Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis | location=Stockholm, Holmia | publisher=Laurentius Salvius | page=824 | author-link=Carl Linnaeus}}</ref> One of the first published descriptions of a blue whale comes from ]'s ''Phalainologia Nova'',<ref name=Sibbald_1692>{{cite journal | author1=Sibbald, Robert | title=Phalainologia Nova | journal=Blue Whale ("Balaenoptera Musculus") | pages=675–678 | date=1692 | author-link=Robert Sibbald}}</ref> after Sibbald found a stranded whale in the estuary of the ], Scotland, in 1692. The name "blue whale" was derived from the Norwegian ''blåhval'', coined by ] shortly after he had perfected the harpoon gun. The Norwegian scientist ] adopted it as the common name in 1874.<ref name=Bortolotti_2008>{{cite book|author1=Bortolotti, D.|title=Wild Blue: A Natural History of the World's Largest Animal | publisher=]|location=New York|date=2008}}</ref>
| author= Barnes LG, McLeod SA.
|editor= Jones ML et al.
|title= The Gray Whale
|year= 1984
|publisher= Academic Press
|location= Orlando, Florida
| isbn = 0123891809
|pages=3–32
|chapter= The fossil record and phyletic relationships of gray whales.}}</ref> but this is not accepted elsewhere.<ref name=msw3/> ] sequencing analysis indicates that the blue whale is ] closer to the ] (''Balaenoptera borealis'') and ] (''Balaenoptera brydei'') than to other ''Balaenoptera'' species, and closer to the ] (''Megaptera'') and the ] (''Eschrichtius'') than to the ]s (''Balaenoptera acutorostrata'' and ''Balaenoptera bonaerensis'').<ref>{{cite journal
|title=Cetacean mitochondrial DNA control region: sequences of all extant baleen whales and two sperm whale species
|author=Arnason, U., Gullberg A. & Widegren, B.
|journal=Molecular Biology and Evolution
|volume=10
|pages=960–970
|date= September 1, 1993 |url=http://mbe.oxfordjournals.org/cgi/content/abstract/10/5/960
|accessdate=2009-01-25
|pmid=8412655
|issue=5
}}</ref><ref>{{cite journal
|title=Mitochondrial Phylogenetics and Evolution of Mysticete Whales
|author=Sasaki, T
|journal=Systematic Biology
|volume=54
|issue=1
|pages=77–90
|date=February 23, 2005
|doi=10.1080/10635150590905939
|url=http://www.informaworld.com/smpp/content~content=a716097098~db=all
|accessdate=2009-01-25
|pmid=15805012
|last2=Nikaido
|first2=M
|last3=Hamilton
|first3=H
|last4=Goto
|first4=M
|last5=Kato
|first5=H
|last6=Kanda
|first6=N
|last7=Pastene
|first7=L
|last8=Cao
|first8=Y
|last9=Fordyce
|first9=R}}</ref> If further research confirms these relationships, it will be necessary to reclassify the rorquals.


Blue whales were referred to as "Sibbald's rorqual", after Robert Sibbald, who first described the species.<ref name=Sibbald_1692/> Whalers sometimes referred to them as "sulphur bottom" whales, as the bellies of some individuals are tinged with yellow.<ref name=":0">{{Cite journal |last=Bennett |first=A G |date=1920 |title=On the occurrence of diatoms on the skin of whales |url=https://royalsocietypublishing.org/doi/10.1098/rspb.1920.0021 |journal=Proc. R. Soc. Lond. B |volume=91 |issue=641 |pages=352–357|doi=10.1098/rspb.1920.0021 }}</ref> This tinge is due to a coating of huge numbers of ].<ref name=":0" /> (] briefly refers to "sulphur bottom" whales in his novel '']''.<ref name="Melville_1851" />)
There have been at least 11 documented cases of blue/] hybrid adults in the wild. Arnason and Gullberg describe the genetic distance between a Blue and a Fin as about the same as that between a human and a gorilla.<ref>{{cite journal
| author = A. Arnason and A. Gullberg
| title = Comparison between the complete mtDNA sequences of the blue and fin whale, two species that can hybridize in nature
| journal = Journal of Molecular Ecology
| year = 1993
| volume = 37
|pages = 312–322}}</ref> Researchers working off of Fiji believe they photographed a hybrid ]/blue whale.<ref>. Whale Center of New England (WCNE). Retrieved on 2008-02-27.</ref>


===Evolution===
The specific name ''musculus'' is ] and could mean "muscular", but it can also be interpreted as "little mouse".<ref>{{cite book
{{cladogram |align=right
| last = Simpson
|caption=<small>A ] of six baleen whale species<ref name=Arnason_etal_2018/></small>
| first = D.P.
|clades={{clade|style=font-size:75%;line-height:75%;width:350px;
| title = Cassell's Latin Dictionary
|label1=]
| publisher = Cassell Ltd.
|1={{clade
| year = 1979
|1=]
| edition = 5
|2={{clade
| location = London
|1={{clade
| page = 883
|1='''''B. musculus''''' ('''blue whale''')
| isbn = 0-304-52257-0}}</ref> ], who named the species in his seminal '']'' of 1758,<ref>{{la icon}} {{cite book
|2=''B. borealis'' (])
| last=Linnaeus
}}
| first=C
|2={{clade
| authorlink=Carolus Linnaeus
|1=''Eschrichtius robustus'' (])
| title=Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Tomus I. Editio decima, reformata.
|2={{clade
| publisher=Holmiae. (Laurentii Salvii).
|1=''B. physalus'' (])
| year=1758
|2=''Megaptera novaeangliae'' (])
| page=824
}}
| url= }}</ref> would have known this and may have intended the ironic ].<ref>{{cite web
}}
|url=http://www.dec.ny.gov/animals/9367.html
}}
|title=Blue Whale Fact Sheet
}}
|publisher=New York State Department of Environmental Conservation
}}
| accessdate = 2007-06-29}}</ref> ] called this species '''sulphur-bottom''' in his novel '']'' due to an orange-brown or yellow tinge on the underparts from ] films on the skin. Other common names for the blue whale have included the '''Sibbald's rorqual''' (after ]), the '''great blue whale''' and the '''great northern rorqual'''. These names have now fallen into disuse.
}}
Blue whales are ] in the family ]. A 2018 analysis estimates that the Balaenopteridae family diverged from other families in between 10.48 and 4.98&nbsp;million years ago during the late ].<ref name=Arnason_etal_2018>{{cite journal | author1=Árnason, U. | author2=Lammers, F. | author3=Kumar, V. | author4=Nilsson, M. A. | author5=Janke, A. | title=Whole-genome sequencing of the blue whale and other rorquals finds signatures for introgressive gene flow | journal=] | volume=4 | issue = 4 | pages=eaap9873 | date=2018| bibcode=2018SciA....4.9873A | doi=10.1126/sciadv.aap9873 | pmid=29632892 | pmc=5884691}}</ref> The earliest discovered anatomically modern blue whale is a partial skull fossil from southern ] identified as ''B.'' cf. ''musculus'', dating to the Early ], roughly 1.5–1.25&nbsp;million years ago.<ref name=Bianucci_etal_2019>{{cite journal | author1=Bianucci, G. | author2=Marx, F. G. | author3=Collareta, A. | author4=Di Stefano, A. | author5=Landini, W. | author6=Morigi, C. | author7=Varola, A. | title=Rise of the titans: baleen whales became giants earlier than thought | journal=] | volume=15 | issue = 5 | page=20190175 | date=2019| doi=10.1098/rsbl.2019.0175 | pmid=31039728 | pmc=6548731}}</ref> The Australian ] diverged during the ]. Their more recent divergence has resulted in the subspecies having a relatively low genetic diversity,<ref name=Attard_etal_2015>{{cite journal | author1=Attard, C. R. M. | author2=Beheregaray, L. B. | author3=Jenner, K. C. S. | author4=Gill, P. C. | author5=Jenner, M.-N. M. | author6=Morrice, M. G. | author7=Teske, P. R. | author8=Moller, L. M. | title=Low genetic diversity in pygmy blue whales is due to climate-induced diversification rather than anthropogenic impacts | journal=Biology Letters | volume=11 | issue=5 | page=20141037 | date=2015| doi=10.1098/rsbl.2014.1037 | pmid=25948571 | pmc=4455730}}</ref> and New Zealand blue whales have an even lower genetic diversity.<ref name=Barlow_etal_2018>{{cite journal | author1=Barlow, D. R. | author2=Torres, L. G. | author3=Hodge, K. B. | author4=Steel, D. | author5=Baker, C. S. | author6=Chandler, T. E. | author7=Bott, N. | author8=Constantine, R. | author9=Double, M. C. | author10=Gill, P. | author11=Glasgow, D. | author12=Hamner, R. M. | author13=Lilley, C. | author14=Ogle, M. | author15=Olson, P. A. | title=Documentation of a New Zealand blue whale population based on multiple lines of evidence | journal=Endangered Species Research | volume=36 | pages=27–40 | date=2018| doi=10.3354/esr00891 | doi-access=free}}</ref>


] suggests that blue whales are most closely related to ]s with gray whales as a ]. This study also found significant ] between minke whales and the ancestors of the blue and sei whale. Blue whales also displayed high genetic diversity.<ref name=Arnason_etal_2018/>
Authorities classify the species into three or four subspecies: ''B. m. musculus'', the ] consisting of the North Atlantic and North Pacific populations, ''B. m. intermedia'', the ] of the ], ''B. m. brevicauda'', the ] found in the Indian Ocean and South Pacific,<ref>Ichihara T. (1966). The pygmy blue whale ''B. m. brevicauda'', a new subspecies from the Antarctic in ''Whales, dolphins and porpoises'' Page(s) 79-113.</ref> and the more problematic ''B. m. indica'', the ], which is also found in the Indian Ocean and, although described earlier, may be the same subspecies as ''B. m. brevicauda''.<ref name=msw3/>


====Hybridization====
==Description and behaviour==
Blue whales are known to ] with ]s. The earliest description of a possible hybrid between a blue whale and a fin whale was a {{cvt|20|m}} anomalous female whale with the features of both the blue and the fin whales taken in the North Pacific.<ref name=Doroshenko_1970>{{cite journal | author1=Doroshenko, V. N. | title=A whale with features of the fin and the blue whale | journal=Izvestia TINRO | volume=70 | pages=255–257 | date=1970}}</ref> A whale captured off northwestern Spain in 1984, was found to have been the product of a blue whale mother and a fin whale father.<ref name=Berube_Aguilar_1998>{{cite journal | author1=Bérubé, M. | author2=Aguilar, A. | title=A new hybrid between a blue whale, ''Balaenoptera Musculus'', and a fin whale, "B. Physalus:" frequency and implications of hybridization | journal=Marine Mammal Science | volume=14 | issue=1 | pages=82–98 | date=1998| doi=10.1111/j.1748-7692.1998.tb00692.x| bibcode=1998MMamS..14...82B }}</ref>
]
]
]
]
] of this blue whale is just visible on the far left.]]
The blue whale has a long tapering body that appears stretched in comparison with the stockier build of other whales.<ref name="des" /> The head is flat and ''U''-shaped and has a prominent ridge running from the ] to the top of the upper lip.<ref name="des" /> The front part of the mouth is thick with ] plates; around 300 plates (each around one metre (3.2&nbsp;ft) long)<ref name="des" /> hang from the upper jaw, running 0.5&nbsp;m (1.6&nbsp;ft) back into the mouth. Between 60 and 90 grooves (called ventral pleats) run along the throat parallel to the body length. These pleats assist with evacuating water from the mouth after lunge feeding (see feeding below).


Two live blue-fin whale ] have since been documented in the Gulf of St. Lawrence (Canada), and in the Azores (Portugal).<ref name=Berube_etal_2017>{{cite conference | author1=Berube, M. | author2=Oosting, T. | author3=Aguilar, A. | author4=Berrow, S. | author5=Hao, W. | author6=Heide-Jørgensen, M. P. | author7=Kovacs, K. M. | author8=Landry, S. | author9=Lydersen, C. | author10=Martin, V. | author11=Øien, N. | author12=Panigada, S. | author13=Prieto, R. | author14=Ramp, C. | author15=Robbins, J. | title=Are the "Bastards" coming back? Molecular identification of live blue and fin whale hybrids in the North Atlantic ocean | conference=22nd Biennial Conference on the Biology of Marine Mammals | location=Halifax, Nova Scotia, Canada | date=2017}}</ref> DNA tests done in Iceland on a blue whale killed in July 2018 by the Icelandic whaling company ], found that the whale was the offspring of a male fin whale and female blue whale;<ref>{{cite web |last=Kilvert|first=Nick|url=https://www.abc.net.au/news/science/2018-07-20/dna-shows-blue-whale-hybrid-iceland-institute-says/10017276 | title=DNA test shows slaughtered blue whale is a hybrid, Iceland marine institute says | date=20 July 2018 | publisher=] | access-date=21 December 2019}}</ref> however, the results are pending independent testing and verification of the samples. Because the International Whaling Commission classified blue whales as a "Protection Stock", trading their meat is illegal, and the kill is an infraction that must be reported.<ref>{{cite web |last=Fishman|first=Margie|url=https://awionline.org/press-releases/hybrid-blue-fin-whale-still-protected | title=Hybrid blue-fin whale is still protected | date=19 July 2018 | publisher=] | access-date=21 December 2019}}</ref> Blue-fin hybrids have been detected from genetic analysis of whale meat samples taken from Japanese markets.<ref name=Palumbi_Cipriano_1998>{{cite journal | author1=Palumbi, S. R. | author2=Cipriano, F. | title=Species identification using genetic tools: the value of nuclear and mitochondrial gene sequences in whale conservation | journal=Journal of Heredity | volume=89 | issue=5 | pages=459–464 | date=1998| doi=10.1093/jhered/89.5.459 | pmid=9768497 | doi-access=free}}</ref> Blue-fin whale hybrids are capable of being fertile. Molecular tests on a {{cvt|70|ft|order=flip}} pregnant female whale caught off Iceland in 1986 found that it had a blue whale mother and a fin whale father, while its fetus was sired by a blue whale.<ref name=Spilliaert_etal_1991>{{cite journal | author1=Spilliaert, R. | author2=Vikingsson, G. | author3=Arnason, U. | author4=Palsdottir, A. | author5=Sigurjonsson, J. | author6=Arnason, A. | title=Species hybridization between a female blue whale (''Balaenoptera rnusctllus'') and a male fin whale ("B.pbysalus"): Molecular and morphological documentation | journal=] | volume=82 | issue=4 | pages=269–274 | date=1991| doi=10.1093/oxfordjournals.jhered.a111085 | pmid=1679066}}</ref>
The ] is small,<ref name="des" /> visible only briefly during the dive sequence. Located around three-quarters of the way along the length of the body, it varies in shape from one individual to another; some only have a barely perceptible lump, but others may have prominent and ] dorsals. When surfacing to breathe, the blue whale raises its shoulder and blowhole out of the water to a greater extent than other large whales such as the ] or ]. Observers can use this trait to differentiate between species at sea. Some blue whales in the North Atlantic and North Pacific raise their tail fluke when diving. When breathing, the whale emits a spectacular vertical single-column spout up to {{convert|12|m|ft}}, typically {{convert|9|m|ft}}. Its ] capacity is 5,000 litres (1320 U.S. gallons). Blue whales have twin blowholes shielded by a large splashguard.<ref name="des" />


In 2024, a genome analysis of North Atlantic blue whales found evidence that approximately 3.5% of the blue whales' genome was derived from hybridization with fin whales. Gene flow was found to be unidirectional from fin whales to blue whales. Comparison with Antarctic blue whales showed that this hybridization began after the separation of the northern and southern populations. Despite their smaller size, fin whales have similar cruising and sprinting speeds to blue whales, which would allow fin males to complete courtship chases with blue females.<ref name=Jossey_et_al_2024>{{cite journal | author1=Jossey, Sushma | author2=Haddrath, O. | author3=Loureiro, L. | author4=Weir, J. | author5=Lim, B. | author6=Miller, J. | author7=Scherer, S. | author8=Goskøyr, A | author9=Lille-Langøy, R | author10=Kovacs, Kit | author11=Lyndersen, C | author12=Routti, H | author13=Engstrom, M | title=Population structure and history of North Atlantic Blue whales (''Balaenoptera musculus musculus'') inferred from whole genome sequence analysis | journal=] | volume=Open access | date=2024-01-06 | issue=2 | pages=357–371 | doi=10.1007/s10592-023-01584-5| doi-access=free | bibcode=2024ConG...25..357J }}</ref>
The flippers are {{convert|3|-|4|m|ft}} long. The upper sides are grey with a thin white border. The lower sides are white. The head and tail fluke are generally uniformly grey. The whale's upper parts, and sometimes the flippers, are usually mottled. The degree of mottling varies substantially from individual to individual. Some may have a uniform slate-grey color, but others demonstrate a considerable variation of dark blues, greys and blacks, all tightly mottled.<ref name="factsheet">{{citeweb
|url=http://www.acsonline.org/factpack/bluewhl.htm
|title=American Cetacean Society Fact Sheet - Blue Whales
|accessdate=20 June 2007
}}</ref>


There is a reference to a humpback–blue whale hybrid in the ], attributed to marine biologist Michael Poole.<ref name=Reeves_etal_2002/><ref name=Hatch_etal_2006>{{cite journal | author1=Hatch, L. T. | author2=Dopman, E. B. | author3=Harrison, R. G. | title=Phylogenetic relationships among the baleen whales based on maternally and paternally inherited characters | journal=] | volume=41 | issue=1 | pages=12–27 | date=2006| doi=10.1016/j.ympev.2006.05.023 | pmid=16843014| bibcode=2006MolPE..41...12H }}</ref>
Blue whales can reach speeds of {{convert|50|km/h|mph}} over short bursts, usually when interacting with other whales, but {{convert|20|km/h|mph}} is a more typical traveling speed.<ref name="factsheet" /> When feeding, they slow down to {{convert|5|km/h|mph}}.


===Subspecies and stocks===
Blue whales most commonly live alone or with one other individual. It is not known how long traveling pairs stay together. In locations where there is a high concentration of food, as many as 50 blue whales have been seen scattered over a small area. However, they do not form the large close-knit groups seen in other baleen species.
At least four subspecies of blue whale are traditionally recognized, some of which are divided into population stocks or "management units".<ref name=NOAA>{{cite report|first1=Chris W. |last1= Oliver|date=November 2020|title= Recovery Plan for the Blue Whale (''Balaenoptera musculus'') |publisher=National Oceanic and Atmospheric Administration |url=https://www.fisheries.noaa.gov/resource/document/recovery-plan-blue-whale-balaenoptera-musculus-0|access-date=12 April 2022}}</ref><ref name=SMM_2016>{{cite web|url=https://www.marinemammalscience.org/species-information/list-marine-mammal-species-subspecies/ |title=List of Marine Mammal Species and Subspecies |date=13 November 2016 | publisher=] |access-date=30 December 2019}}</ref> They have a worldwide distribution, but are mostly absent from the ] and the ], ], and ].<ref name=NOAA/>
]
*Northern subspecies (''B. m. musculus'')
**North Atlantic population – This population is mainly documented from ] along eastern Canada to Greenland, particularly in the ], during summer though some individuals may remain there all year. They also aggregate near Iceland and have increased their presence in the ]. They are reported to migrate south to the ], the ] and northwest Africa.<ref name=NOAA/>
**Eastern North Pacific population – Whales in this region mostly feed off California's coast from summer to fall and then Oregon, Washington State, the ] and ] later in the fall. During winter and spring, blue whales migrate south to the waters of Mexico, mostly the ], and the ], where they both feed and breed.<ref name=NOAA/>
**Central/Western Pacific population – This stock is documented around the ] during the summer; some individuals may remain there year-round. They have been recorded wintering in Hawaiian waters, though some can be found in the ] during fall and early winter.<ref name=NOAA/>
*Northern Indian Ocean subspecies (''B. m. indica'') – This subspecies can be found year-round in the northwestern Indian Ocean, though some individuals have recorded travelling to the ] during between summer and fall.<ref name=NOAA/>
*Pygmy blue whale (''B. m. brevicauda'')
**Madagascar population – This population migrates between the ] and ] in the north and the ]s and ] in the south were they feed, passing through the ].<ref name=NOAA/>
**Australia/Indonesia population – Whales in this region appear to winter off Indonesia and migrate to their summer feeding grounds off the coast of Western Australia, with major concentrations at ] and an area stretching from the ] and ].<ref name=NOAA/>
**Eastern Australia/New Zealand population – This stock may reside in the ] and the ] in winter and feed mostly in the ] and off the coast of eastern ]. Blue whales have been detected around New Zealand throughout the year.<ref name=NOAA/>
*Antarctic subspecies (''B. m. intermedia'') – This subspecies includes all populations found around the Antarctic. They have been recorded to travel as far north as eastern tropical Pacific, the central Indian Ocean, and the waters of southwestern Australia and northern New Zealand.<ref name=NOAA/>


Blue whales off the ]an coast might be a separate subspecies based on their geographic separation, genetics, and unique song types.<ref name=LeDuc_etal_2007>{{cite journal | author1=LeDuc, R. G. | author2=Dizon, A. E. | author3=Goto, M. | author4=Pastene, L. A. | author5=Kato, H. | author6=Nishiwaki, S. | author7=LeDuc, C. A. | author8=Brownell, R. L. | title=Patterns of genetic variation in Southern Hemisphere blue whales, and the use of assignment test to detect mixing on the feeding grounds | journal=Journal of Cetacean Research and Management | volume=9 | pages=73–80 | date=2023| doi=10.47536/jcrm.v9i1.694 | s2cid=257136658 | doi-access=free }}</ref><ref name=Torres-Florez_etal_2015>{{cite journal | author1=Torres-Florez, J. P. | author2=Olson, P. A. | author3=Bedrinana-Romano, L. | author4=Rosenbaum, H. | author5=Ruiz, J. | author6=Leduc, R. | author7=Huck-Gaete, R. | title=First documented migratory destination for eastern South Pacific blue whales | journal=Marine Mammal Science | volume=31 | issue=4 | pages=1580–1586 | date=2015| doi=10.1111/mms.12239 | doi-access=free | bibcode=2015MMamS..31.1580T }}</ref><ref name=Buchan_etal_2010>{{cite journal | author1=Buchan, S. J. | author2=Rendell, L. E. | author3=Hucke-Gaete, R. | title=Preliminary recordings of blue whale (''Balaenoptera musculus'') vocalizations in the Gulf of Corcovado, northern Patagonia Chile | journal=Marine Mammal Science | volume=26 | issue=2 | pages=451–459 | date=2010| doi=10.1111/j.1748-7692.2009.00338.x | bibcode=2010MMamS..26..451B }}</ref> Chilean blue whales might overlap in the ] with ] blue whales and Eastern North Pacific blue whales. Chilean blue whales are genetically differentiated from Antarctica blue whales such that ] is unlikely. However, the genetic distinction is less between them and the Eastern North Pacific blue whale, hence there might be gene flow between the Southern and Northern Hemispheres.<ref name=LeDuc_etal_2016>{{cite journal | author1=LeDuc, R. G. | author2=Archer, E. I. | author3=Lang, A. R. | author4=Martien, K. K. | author5=Hancock-Hanser, B. | author6=Torres-Florez, J. P. | author7=Hucke-Gaete, R. | author8=Rosenbaum, H. R. | author9=Van Waerebeek, K. | author10=Brownell, R. L. Jr. | author11=Taylor, B. L. | title=Genetic variation in blue whales in the eastern Pacific: implication for taxonomy and use of common wintering grounds | journal=] | volume=26 | issue=3 | pages=740–751 | date=2016| doi=10.1111/mec.13940 | pmid=27891694 | s2cid=206184206 }}</ref> A 2019 study by Luis Pastene, Jorge Acevedo and Trevor Branch provided new morphometric data from a survey of 60 Chilean blue whales, hoping to address the debate about the possible distinction of this population from others in the Southern Hemisphere. Data from this study, based on whales collected in the 1965/1966 whaling season, shows that both the maximum and mean body length of Chilean blue whales lies between these values in pygmy and Antarctic blue whales. Data also indicates a potential difference in snout-eye measurements between the three, and a significant difference in fluke-anus length between the Chilean population and pygmy blue whales. This further confirms Chilean blue whales as a separate population, and implies that they do not fall under the same subspecies as the pygmy blue whale (''B. m. brevicauda'').<ref name=Pastene_etal_2019>{{Cite journal |last1=Pastene |first1=Luis A. |last2=Acevedo |first2=Jorge |last3=Branch |first3=Trevor A. |date=2019 |title=Morphometric analysis of Chilean blue whales and implications for their taxonomy |url=https://onlinelibrary.wiley.com/doi/10.1111/mms.12625 |journal=Marine Mammal Science |language=en |volume=36 |issue=1 |pages=116–135 |doi=10.1111/mms.12625 |issn=0824-0469}}</ref>
===Size===
] in the collections of the ].]]
Blue whales are difficult to weigh because of their size. Most blue whales killed by whalers were not weighed whole, but cut up into manageable pieces first. This caused an underestimate of the total weight of the whale, due to the loss of blood and other fluids. Nevertheless, measurements between {{convert|150|-|170|metric ton |short ton}} were recorded of animals up to {{convert|27|m|ft}} in length. The weight of an individual {{convert|30|m|ft}} long is believed by the American ] (NMML) to be in excess of {{convert|180|metric ton|short ton}}. The largest blue whale accurately weighed by NMML scientists to date was a female that weighed {{convert|177|metric ton|short ton}}.<ref name=pop />


A 2024 genomic study of the global blue whale population found support for the subspecific status of Antarctic and Indo-western Pacific blue whales but not eastern Pacific blue whales. The study found "...divergence between the eastern North and eastern South Pacific, and among the eastern Indian Ocean, the western South Pacific and the northern Indian Ocean." and "no divergence within the Antarctic".<ref>{{cite journal|author1=Attard, C. R. M.|author2=Sandoval-Castillo, J|author3=Lang, A. R.|author4=Vernazzani, B. G.|author5=Torres, L. G.|author6=Baldwin, R|author7=Jenner, K. C. S.|author8=Gill, P. C.|author9=Burton, C. L. K.|author10=Barceló, A|author11=Sironi, M|author12=Jenner, M.-N. M.|author13=Morrice, M. G.|author14=Beheregaray, L. B.|author15=Möller, L. M.|year=2024|title=Global conservation genomics of blue whales calls into question subspecies taxonomy and refines knowledge of population structure|journal=Animal Conservation|volume=27|issue=5|pages=626–638|doi=10.1111/acv.12935|bibcode=2024AnCon..27..626A |doi-access=free}}</ref>
The blue whale is the largest animal ever known to have lived.<ref name="des">{{citeweb
|url=http://www.wdcs.org/dan/publishing.nsf/allweb/F8FE8974A62E12F88025696D004A8EE9
|title=Size and Description of the Blue Whale Species
|accessdate=15 June 2007
}}</ref> The largest known ] of the ] Era was the '']'',<ref>{{es icon}} {{cite journal
|author= Bonaparte J, Coria R
|year= 1993
|title=Un nuevo y gigantesco sauropodo titanosaurio de la Formacion Rio Limay (Albiano-Cenomaniano) de la Provincia del Neuquen, Argentina
|journal= Ameghiniana
|volume=30
|issue= 3
|pages=271–282}}</ref> which is estimated to have weighed up to {{convert|90|metric ton|short ton}}, though a controversial vertebra of ''] fragillimus'' may indicate an animal of up to {{convert|122|metric ton|short ton}} and {{convert|40|-|60|m|ft}}.<ref name="carpenter2006">Carpenter, K. (2006). "Biggest of the big: a critical re-evaluation of the mega-sauropod ''Amphicoelias fragillimus''." In Foster, J.R. and Lucas, S.G., eds., 2006, ''Paleontology and Geology of the Upper Jurassic Morrison Formation.'' New Mexico Museum of Natural History and Science Bulletin '''36''': 131-138.</ref> Furthermore, there are weight estimates for the very poorly known '']'' ranging from {{convert|140|-|220|metric ton|short ton}}, besides length estimates up to about {{convert|45|m|ft}}. The extinct fish ] may have approached its size.<ref>{{cite web
|url=http://news.nationalgeographic.com/news/2003/10/1001_031001_biggestfish.html
|title=&quot;Biggest Fish Ever Found&quot; Unearthed in U.K
|publisher=News.nationalgeographic.com
|date=October 1, 2003
|accessdate=2008-11-03}}</ref> However, complete fossils are difficult to come by, making size comparisons difficult. All these animals are considered to be smaller than the blue whale.


==Description==
There is some uncertainty about the biggest blue whale ever found, as most data comes from blue whales killed in ] waters during the first half of the twentieth century and was collected by whalers not well-versed in standard zoological measurement techniques. The longest whales ever recorded were two females measuring {{convert|33.6|-|33.3|m|ft}} respectively.<ref name = "SearsCal02">{{cite paper
], showing the blowhole]]
| author = Sears R, Calambokidis J
The blue whale is a slender-bodied cetacean with a broad U-shaped head; thin, elongated ]; a small {{convert|13|in|cm|order=flip|sp=us}} sickle-shaped dorsal fin located close to the tail, and a large tail stock at the root of the wide and thin ]s. The upper jaw is lined with 70–395 black ] plates. The throat region has 60–88 grooves which allows the skin to expand during feeding.<ref name="Reeves_etal_2002">{{cite book | last1=Reeves | first1=R. R. | last2=Stewart | first2=P. J. | last3=Clapham | first3=J. | last4=Powell | first4=J. A. | title=Whales, dolphins, and porpoises of the eastern North Pacific and adjacent Arctic waters: A guide to their identification | location=New York | publisher=] | pages=234–237 | date=2002}}</ref><ref name="Calamb_Steig_1997" /><ref name="Sears_Perr_2009" /><ref name="Leatherwood_etal_1976" /><ref name="Leatherwood_etal_1982">{{cite journal | author1=Leatherwood, S. | author2=Reeves, R. R. | author3=Perrin, W. F. | author4=Evans, W. E. | title=Whales, dolphins, and porpoises of the eastern North Pacific and adjacent Arctic waters: A guide to their identification | journal=NOAA Technical Report NMFS Circular | volume=444 | page=245 | date=1982 | url=https://repository.library.noaa.gov/view/noaa/5472}}</ref> It has two ] that can squirt {{convert|30|–|40|ft|order=flip|sp=us}} up in the air.<ref name="Reeves_etal_2002" /><ref name="Sears_Perr_2009" /><ref name="Leatherwood_etal_1976" /> The skin has a mottled grayish-blue coloration, appearing blue underwater.<ref name=Calamb_Steig_1997>{{cite book | last1=Calambokidis | first1=J. | last2=Steiger | first2=G. H. | title=Blue Whales | location=McGregor, MN | publisher=Voyager Press | page=72 | date=1997}}</ref><ref name=Sears_Perr_2009>{{cite book | author1=Sears, R. | author2=Perrin, W. F. | title=Encyclopedia of marine mammals | location=San Diego, CA | publisher=] | pages=120–124 | chapter=Blue whale (''Balaenoptera musculus'') | editor1-last=Perrin | editor1-first=W. F. | editor2-last=Würsig | editor2-first=B. | editor3-last=Thewissen | editor3-first=J. G. M. | date=2009}}</ref><ref name="Leatherwood_etal_1976">{{cite journal|author1=Leatherwood, S.|author2=Caldwell, D. K.|author3=Winn, H. E.|date=1976|title=Whales, dolphins, and porpoises of the western North Atlantic|url=http://aquaticcommons.org/1417/|journal=NOAA Technical Report NMFS Circular|volume=396|page=176|access-date=31 December 2019|archive-date=20 July 2020|archive-url=https://web.archive.org/web/20200720121225/http://aquaticcommons.org/1417/|url-status=dead}}</ref> The mottling patterns near the ] vary between individuals.<ref name="Sears_etal_1990">{{cite journal | author1=Sears, R. | author2=Williamson, J. M. | author3=Wenzel, F. W. | author4=Bérubé, M. | author5=Gendron, D. | author6=Jones, P. | title=Photographic identification of the blue whale (''Balaenoptera musculus'') in the Gulf of St. Lawrence, Canada | journal=] | volume=12 | pages=335–342 | date=1990}}</ref><ref name="Calambokidis_etal_2009">{{cite journal | author1=Calambokidis, J. | author2=Barlow, J. | author3=Ford, J. K. B. | author4=Chandler, T. E. | author5=Douglas, A. B. | title=Insights into the population structure of blue whales in the Eastern North Pacific from recent sightings and photographic identification | journal=] | volume=25 | issue=4 | pages=816–832 | date=2009| doi=10.1111/j.1748-7692.2009.00298.x | bibcode=2009MMamS..25..816C | s2cid=83527877 | url=https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1246&context=usdeptcommercepub }}</ref><ref name="Gendron_2012">{{cite journal | author1=Gendron, D. | author2=De La Cruz, U. | author3=Winn, H. E. | title=A new classification method to simplify blue whale photo-identification technique | journal=Journal of Cetacean Research and Management | volume=13 | issue=1 | pages=79–84 | date=2012}}</ref> The underbelly has lighter pigmentation and can appear yellowish due to ]s in the water,<ref name="Calamb_Steig_1997" /><ref name="Sears_Perr_2009" /><ref name="Leatherwood_etal_1976" /> which historically earned them the nickname "sulphur bottom".<ref name="Melville_1851">{{cite book | last1=Melville | first1=H.|author-link=Herman Melville | title=] | location=New York | publisher=] | page=398 | date=1851}}</ref><ref name="Scammon_1874">{{cite book | last1=Scammon | first1=C. M. | title=The Marine Mammals of the Northwestern Coast of North America | location=New York | publisher=Dover | date=1874}}</ref> The male blue whale has the ] in the animal kingdom, at around {{convert|3|m|ft|abbr=on}} long and {{convert|12|in|cm|abbr=on}} wide.<ref name = "bioweb">{{cite web|url=http://bioweb.uwlax.edu/bio203/s2012/olson_rile/reproduction.htm|title=Reproduction|publisher=]|access-date=3 October 2012}}</ref>
| title = Update COSEWIC status report on the blue whale Balaenoptera musculus in Canada.
| publisher = Committee on the Status of Endangered Wildlife in Canada, Ottawa.
| year = 2002
| pages = 32}}</ref> The longest whale measured by ]s at the NMML was {{convert|29.9|m|ft}}.<ref name=pop />


=== Size ===
A blue whale's ] weighs around {{convert|2.7|metric ton|short ton}}<ref name="SM">{{cite book
] measuring {{convert|19|ft|m|order=flip|sp=us}}]]
|title=The Scientific Monthly
The blue whale is the largest animal known ever to have existed.<ref name="Ruud_1956">{{cite journal|author1=Ruud, J. T.|date=1956|title=The blue whale|journal=]|volume=195|issue=6|pages=46–50|doi=10.1038/scientificamerican1256-46|bibcode=1956SciAm.195f..46R}}</ref><ref name="Lockyer_1981">{{cite journal|author1=Lockyer, C.|date=1981|title=Growth and energy budgets of large baleen whales from the southern hemisphere|journal=FAO Fisheries Series (5) Mammals in the Seas|volume=3|pages=379–487}}</ref><ref name="Mizroch_1984">{{cite journal|author1=Mizroch, S. A.|author2=Rice, D. W.|author3=Breiwick, J. M.|date=1984|title=The blue whale, ''Balaenoptera musculus''|journal=Marine Fisheries Review|volume=46|pages=15–19}}</ref> Some studies have estimated that certain ] ]s and the ancient whale '']'' could have rivalled the blue whale in size, with ''Perucetus'' also being heavier than the blue whale with a mean weight of {{cvt|180|t}}.<ref name="AT23" /><ref name="PLOS One2018">{{cite journal |last1=De la Salle |first1=Paul |last2=R. Lomax |first2=Dean |last3=A. Massare |first3=Judy |last4=Gallois |first4=Ramues |name-list-style=vanc |year=2018 |title=A giant Late Triassic ichthyosaur from the UK and a reinterpretation of the Aust Cliff 'dinosaurian' bones |url=https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0194742 |journal=PLOS ONE |volume=13 |issue=4 |doi=10.6084/m9.figshare.5975440}}</ref> These estimates are based on fragmentary remains, and the proposed size for the latter has been disputed in 2024.<ref name=MP24>{{Cite journal|last1=Motani |first1=R. |last2=Pyenson |first2=N. D. |year=2024 |title=Downsizing a heavyweight: factors and methods that revise weight estimates of the giant fossil whale ''Perucetus colossus'' |journal=PeerJ |volume=12 |at=e16978 |doi=10.7717/peerj.16978 |doi-access=free |pmid=38436015 |pmc=10909350 }}</ref> Other studies estimate that on land, large ] like '']'' (mean weight: 110–170 tons) and '']'' (mean weight: 80–120 tons) would have easily rivalled the blue whale, with the former even exceeding the blue whale based on its most liberal estimations (240 tons), although these estimates are based on even more fragmentary specimens that had disintegrated by the time those estimates were made.<ref name="Bruhathkayosaurus2023">{{Cite journal |last1=Paul |first1=Gregory S. |last2=Larramendi |first2=Asier |date=11 April 2023 |title=Body mass estimate of ''Bruhathkayosaurus'' and other fragmentary sauropod remains suggest the largest land animals were about as big as the greatest whales |journal=Lethaia |language=en |volume=56 |issue=2 |pages=1–11 |doi=10.18261/let.56.2.5 |bibcode=2023Letha..56..2.5P |s2cid=259782734 |issn=0024-1164}}</ref>
|publisher=American Association for
the Advancement of Science
|year=1915
|page=21}}</ref> and, when fully expanded, its mouth is large enough to hold up to {{convert|90|metric ton|short ton}} of food and water.<ref name="wheelock" /> Despite the size of its mouth, the dimensions of its throat are such that a blue whale cannot swallow an object wider than a beach ball.<ref>Blue Planet: Frozen seas (BBC documentary)</ref> Its ] weighs {{convert|600|kg|lb}} and is the ] known in any animal.<ref name="SM" /> A blue whale's ] is about {{convert|23|cm|in}} in diameter.<ref>{{cite web
|url=http://www2.ucsc.edu/seymourcenter/PDF/2.%20Ms.%20B%20measurements.pdf
|title=Ms. Blue's Measurements
|author=Caspar, Dave
|year=2001
| month=April
|accessdate=2006-09-01
|publisher=Seymour Center, University of California, Santa Cruz.
|format=PDF}}</ref> During the first seven months of its life, a blue whale calf drinks approximately 400 litres (100 U.S. gallons) of milk every day. Blue whale calves gain ] quickly, as much as {{convert|90|kg|lb}} every 24 hours. Even at birth, they weigh up to {{convert|2700|kg|lb}}—the same as a fully grown ].<ref name="factsheet" />


The ] (IWC) whaling database reports 88 individuals longer than {{convert|30|m|sp=us}}, including one of {{convert|33|m|sp=us}}.<ref name="McClain_2015">{{cite journal | author1=McClain, C. R. | author2=Balk, M. A. | author3=Benfield, M. C. | author4=Branch, T. A. | author5=Chen, C. | author6=Cosgrove, J. | author7=Dove, A. D. M. | author8=Helm, R. R. | author9=Hochberg, F. G. | author10=Gaskins, L. C. | author11=Lee, F. B. | author12=Marshall, A. | author13=McMurray, S. E. | author14=Schanche, C. | author15=Stone, S. N. | title=Sizing ocean giants: patterns of intraspecific size variation in marine megafauna | journal=] | volume=e715 | page=e715 | date=2015 | doi=10.7717/peerj.715| pmid=25649000 | pmc=4304853 | doi-access=free }}</ref> The ] reported lengths up to {{convert|102|ft|order=flip|sp=us}}.<ref name=Mackintosh_1942>{{cite journal | author1=Mackintosh, N. A. | title=The southern stocks of whalebone whales | journal=] | volume=22 | issue=3889 | pages=569–570 | date=1942| url=https://archive.org/details/cbarchive_120108_thesouthernstocksofwhalebonewh1943/page/n9/mode/2up| bibcode=1944Natur.153..569F | doi=10.1038/153569a0 | s2cid=41590649 }}</ref> The longest scientifically measured individual blue whale was {{convert|98|ft|order=flip|sp=us}} from rostrum tip to tail notch.<ref name=Sears_Calamb_2002>{{cite book | last1=Sears | first1=R. | last2=Calambokidis | first2=J. | title=Update COSEWIC status report on the blue whale (''Balaenoptera musculus'') in Canada | location=Ottawa, ON | publisher=] | page=32 | date=2002}}</ref> Female blue whales are larger than males.<ref name=Sears_Perr_2009/><ref name=Ralls_1976>{{cite journal | author1=Ralls, K. | title=Mammals in which females are larger than males | journal=] | volume=51 | issue=2 | pages=245–270 | date=1976| doi=10.1086/409310 | pmid=785524 | s2cid=25927323 }}</ref> Hydrodynamic models suggest a blue whale could not exceed {{convert|33|m|ft}} because of metabolic and energy constraints.<ref name=Potvin_2012>{{cite journal | author1=Potvin, J. | author2=Goldbogen, J. | author3=Chadwick, R. E. | title=Metabolic Expenditures of Lunge Feeding Rorquals Across Scale: Implications for the Evolution of Filter Feeding and the Limits to Maximum Body Size | journal=] | volume=7 | issue=9 | page=e44854 | doi=10.1371/journal.pone.0044854 | pmid=23024769 | pmc=3443106 | date=2012| bibcode=2012PLoSO...744854P | doi-access=free }}</ref>
===Feeding===
Blue whales feed almost exclusively on ], though they also take small numbers of ].<ref name="afsc">{{cite web
|url=http://www.afsc.noaa.gov/nmml/education/cetaceans/blue.php
|title=Detailed Information about Blue Whales
|publisher=Alaska Fisheries Science Center
|year=2004
| accessdate = 2007-06-14}}</ref> The species of this ] eaten by blue whales varies from ocean to ocean. In the North Atlantic, '']'', '']'', '']'' and '']'' are the usual food;<ref>{{cite journal
|author= Hjort J, Ruud JT
|year=1929
|title=Whaling and fishing in the North Atlantic
|journal= Rapp. Proc. Verb. Conseil int. Explor. Mer
|volume= 56
|issue=
|pages= }}</ref><ref>{{cite journal
|author=Christensen I, Haug T, Øien N
|year=1992
|title= A review of feeding and reproduction in large baleen whales (Mysticeti) and sperm whales ''Physeter macrocephalus'' in Norwegian and adjacent waters
|journal= Fauna Norvegica Series a
|volume= 13
|issue=
|pages=39–48}}</ref><ref>{{cite journal
|author= Sears R, Wenzel FW, Williamson JM
|year=1987
|title=The Blue Whale: A Catalogue of Individuals from the Western North Atlantic (Gulf of St. Lawrence)
|journal=Mingan Island Cetacean Study, St. Lambert, Quebec.
|pages=27}}</ref> in the North Pacific, '']'', '']'', '']'', '']'', '']'' and '']'';<ref>{{cite journal
|last=Sears
|first=R
|year=1990
|title= The Cortez blues
|journal= Whalewatcher
|volume=24
|issue=2
|pages=12–15}}</ref><ref>{{cite journal
|last=Kawamura
|first=A
|year= 1980
|title= A review of food of balaenopterid whales
|journal= Sci. Rep. Whales Res. Inst.
|volume=32
|issue=
|pages=155–197}}</ref><ref>{{cite book
|author=Yochem PK, Leatherwood S
|editor=Ridgway SH, Harrison R
|title= Handbook of Marine Mammals, Vol. 3:The Sirenians and Baleen Whales.
|edition=
|year=1980
|publisher=Academic Press
|location=London
|isbn=
|oclc=
|doi=
|id=
|pages= 193–240
|chapter= Blue whale ''Balaenoptera musculus'' (Linnaeus, 1758)}}</ref> and in the Antarctic, '']'', '']'' and '']''.


The average length of sexually mature female blue whales is {{convert|72.1|ft|order=flip|sp=us}} for Eastern North Pacific blue whales, {{convert|79|ft|order=flip|sp=us}} for central and western North ] blue whales, {{convert|68–78|ft|order=flip|sp=us}} for North ] blue whales, {{convert|83.4|–|86.3|ft|order=flip|sp=us}} for Antarctic blue whales, {{convert|77.1|ft|order=flip|sp=us}} for Chilean blue whales, and {{convert|69.9|ft|order=flip|sp=us}} for pygmy blue whales.<ref name="McClain_2015"/><ref name=Branch_2007a>{{cite journal | author1=Branch, T. A. | author2=Abubaker, E. M. N. | author3=Mkango, S. | author4=Butterworth, D. S. | title=Separating southern blue whale subspecies based on length frequencies of sexually mature females | journal=] | volume=23 | issue=4 | pages=803–833 | date=2007| doi=10.1111/j.1748-7692.2007.00137.x | bibcode=2007MMamS..23..803B }}</ref><ref name=Gilpatrick_Perryman_2008>{{cite journal | author1=Gilpatrick, J. W. | author2=Perryman, W. L. | title=Geographic variation in external morphology of North Pacific and Southern Hemisphere blue whales (''Balaenoptera musculus'') | journal=Journal of Cetacean Research and Management | volume=10 | issue=1 | pages=9–21 | date=2008| doi=10.47536/jcrm.v10i1.654 | s2cid=256926335 | doi-access=free }}</ref>
An adult blue whale can eat up to 40 million krill in a day.<ref></ref> The whales always feed in the areas with the highest concentration of krill, sometimes eating up to {{convert|3600|kg|lb}} of krill in a single day.<ref name="afsc" /> This daily calorie requirement of an adult blue whale is in the region of 1.5 million.<ref>] (2007), ''Extraordinary Animals: An Encyclopedia of Curious and Unusual Animals'', ].</ref>


In the Northern Hemisphere, males weigh an average {{convert|100|t|lb|sp=us}} and females {{convert|112|t|lb|sp=us}}. Eastern North ] blue whale males average {{convert|88.5|t|lb|sp=}} and females {{convert|100|t|lb|sp=}}. Antarctic males average {{convert|112|t|lb|sp=}} and females {{convert|130|t|lb|sp=}}. Pygmy blue whale males average {{convert|83.5|t|lb|sp=}} to {{convert|99|t|lb|sp=}}.<ref name=Lockyer_1976>{{cite journal | author1=Lockyer, C. | title=Body weights of some species of large whales | journal=] | volume=36 | issue=3 | pages=259–273 | date=1976| doi=10.1093/icesjms/36.3.259 }}</ref> The weight of the heart of a stranded North Atlantic blue whale was {{convert|180|kg|lb|abbr=on|sp=}}, the largest known in any animal.<ref>{{cite web |url=http://www.bbc.com/earth/story/20150820-see-the-worlds-biggest-heart-blue-whales-is-first-to-be-preserved?ns_mchannel=social&ns_campaign=BBC_iWonder&ns_source=twitter&ns_linkname=knowledge_and_learning |title=See the world's biggest heart |access-date=21 August 2015 |archive-date=16 September 2020 |archive-url=https://web.archive.org/web/20200916133445/http://www.bbc.com/earth/story/20150820-see-the-worlds-biggest-heart-blue-whales-is-first-to-be-preserved?ns_mchannel=social&ns_campaign=BBC_iWonder&ns_source=twitter&ns_linkname=knowledge_and_learning |url-status=dead }}</ref> The record-holder blue whale was recorded at {{convert|173|tonne|short ton|-1|lk=on|abbr=off}},<ref>{{cite web | title = Assessment and Update Status Report on the Blue Whale ''Balaenoptera musculus'' | publisher = Committee on the Status of Endangered Wildlife in Canada | year = 2002 | url = http://www.sararegistry.gc.ca/virtual_sara/files/cosewic/sr_blue_whale_e.pdf | access-date = 19 April 2007}}</ref> with estimates of up to {{convert|199|tonne|short ton|-1|lk=on|abbr=off}}.<ref>{{cite journal |last1=McClain |first1=Craig R. |last2=Balk |first2=Meghan A. |last3=Benfield |first3=Mark C. |last4=Branch |first4=Trevor A. |last5=Chen |first5=Catherine |last6=Cosgrove |first6=James |last7=Dove |first7=Alistair D.M. |last8=Gaskins |first8=Leo |last9=Helm |first9=Rebecca R. |last10=Hochberg |first10=Frederick G. |last11=Lee |first11=Frank B. |last12=Marshall |first12=Andrea |last13=McMurray |first13=Steven E. |last14=Schanche |first14=Caroline |last15=Stone |first15=Shane N. |last16=Thaler |first16=Andrew D. |title=Sizing ocean giants: patterns of intraspecific size variation in marine megafauna |journal=PeerJ |date=13 January 2015 |volume=3 |pages=e715 |doi=10.7717/peerj.715 |pmid=25649000 |pmc=4304853 |doi-access=free }}</ref>
Because krill move, blue whales typically feed at depths of more than {{convert|100|m|ft}} during the day and only surface-feed at night. Dive times are typically 10 minutes when feeding, though dives of up to 20 minutes are common. The longest recorded dive is 36 minutes<ref name=Sears98>(Sears 1998)</ref>. The whale feeds by lunging forward at groups of krill, taking the animals and a large quantity of water into its mouth. The water is then squeezed out through the baleen plates by pressure from the ventral pouch and tongue. Once the mouth is clear of water, the remaining krill, unable to pass through the plates, are swallowed. The blue whale also incidentally consumes small fish, crustaceans and squid caught up with krill.<ref>{{cite journal
|author= Nemoto T
|year=1957
|title=Foods of baleen whales in the northern Pacific
|journal= Sci. Rep. Whales Res. Inst.
|volume=12
|pages=33–89}}</ref><ref>{{cite journal
|author=Nemoto T, Kawamura A
|year=1977
|title= Characteristics of food habits and distribution of baleen whales with special reference to the abundance of North Pacific sei and Bryde’s whales
|journal=Rep. Int. Whal. Commn
|volume= 1
|issue=Special Issue
|pages=80–87}}</ref>


In 2024, Motani and Pyenson calculated the body mass of blue whales at different lengths, compiling records of their sizes from previous academic literatures and using regression analyses and volumetric analyses. A {{convert|25|m|ft}} long individual was estimated to weigh approximately {{convert|101|-|119|tonne|ST}}, while a {{convert|30|m|ft}} long individual was estimated to weigh approximately {{convert|184|-|205|tonne|ST}}. Considering that the largest blue whale was indeed {{convert|33|m|ft}} long, they estimated that a blue whale of such length would have weighed approximately {{convert|252|-|273|tonne|ST}}.<ref name=MP24/>
===Life history===
]
Mating starts in late autumn and continues to the end of winter.<ref name="Art">{{citeweb
|url=http://www.articleworld.org/index.php/Blue_Whale
|title=Blue Whale - ArticleWorld
|accessdate=2 July 2007
}}</ref> Little is known about mating behaviour or breeding grounds. Females typically give birth once every two to three years at the start of the winter after a ] of ten to twelve months.<ref name="Art" /> The calf weighs about {{convert|2.5|metric ton|short ton}} and is around {{convert|7|m|ft}} in length. Blue whale calves drink 380&ndash;570 litres (100&ndash;150 U.S. gallons) of milk a day. ] takes place for about six months, by which time the calf has doubled in length. Sexual maturity is typically reached at eight to ten years, by which time males are at least {{convert|20|m|ft}} long (or more in the Southern Hemisphere). Females are larger still, reaching sexual maturity at around the age of five, by which they are about {{convert|21|m|ft}} long.


During the harvest of a female blue whale, Messrs. Irvin and Johnson collected a fetus that is now 70% preserved and used for educational purposes. The fetus was collected in 1922, so some shrinkage may have occurred, making visualization of some features fairly difficult. However, due to this collection researchers now know that the external anatomy of a blue whale fetus is approximately 133&nbsp;mm. Along with during the developmental phases, the fetus is located where the embryonic and fetal phases converge. This fetus is the youngest gestational age of the specimen recorded.<ref>{{Cite journal |last=Roston |first=Rachel A. |date=2013 |title=Anatomy and Age Estimation of an Early Blue Whale (Balaenoptera musculus) Fetus |url=https://anatomypubs.onlinelibrary.wiley.com/doi/pdf/10.1002/ar.22678 |access-date=November 23, 2024 |journal=The Anatomical Record|volume=296 |issue=4 |pages=709–722 |doi=10.1002/ar.22678 |pmid=23447333 |doi-access=free }}</ref>
Scientists estimate that blue whales can live for at least 80 years;<ref name = "SearsCal02"/><ref name="Art" /><ref name="npca">{{citeweb
|url=http://www.npca.org/marine_and_coastal/marine_wildlife/bluewhale.html
|title=www.npca.org
|accessdate=21 June 21, 2007
}}</ref> however, since individual records do not date back into the whaling era, this will not be known with certainty for many years. The longest recorded study of a single individual is 34 years, in the north-east Pacific.<ref name=Sears98/> The whales' only natural predator is the ].<ref>{{cite journal
| title = Sightings and movements of blue whales off central California from 1986–88 from photo-identification of individuals
| author = J. Calambokidis, G. H. Steiger, J. C. Cubbage, K. C. Balcomb, C. Ewald, S. Kruse, R. Wells and R. Sears
| journal = Rep. Whal. Comm.
| volume = 12
| pages = 343–348
| year = 1990}}</ref> Studies report that as many as 25% of mature blue whales have scars resulting from Orca attacks.<ref name = "SearsCal02"/> The mortality rate of such attacks is unknown.


=== Life span ===
Blue whale strandings are extremely uncommon, and, because of the species' social structure, mass strandings are unheard of.<ref>William Perrin and Joseph Geraci. "Stranding" pp 1192–1197 in ''Encyclopedia of Marine Mammals'' (Perrin, Wursig and Thewissen eds)</ref> However, when strandings do occur, they can become the focus of public interest. In 1920, a blue whale washed up near ] on the ] in the ] of ]. It had been shot in the head by whalers, but the harpoon had failed to explode. As with other mammals, the fundamental instinct of the whale was to try to carry on breathing at all costs, even though this meant beaching to prevent itself from drowning. Two of the whale's bones were erected just off a main road on Lewis and remain a tourist attraction.<ref>{{cite web
Blue whales live around 80–90 years or more.<ref name=Sears_Perr_2009/><ref name=natgeo/> Scientists look at a blue whale's ] or ear plug to estimate its age. Each year, a light and dark layer of wax is laid corresponding with fasting during migration and feeding time. Each set is thus an indicator of age.<ref name=Purves_1955>{{cite journal | author1=Purves, P. E. | title=The wax plug in the external auditory meatus of the | journal=Discovery Reports | volume=27 | pages=259–273 | date=1955}}</ref><ref name=Gabriele_etal_2010>{{cite journal | author1=Gabriele, C. M. | author2=Lockyer, C. | author3=Straley, J. M. | author4=Juasz, C. M. | author5=Kato, H. | title=Sighting history of a naturally marked humpback whale (''Megaptera novaeangliae'') suggests ear plug growth layer groups are deposited annually | journal=Marine Mammal Science | volume=26 | issue=2 | pages=443–450 | date=2010| doi=10.1111/j.1748-7692.2009.00341.x | bibcode=2010MMamS..26..443G }}</ref><ref name=Lockyer_1984a>{{cite journal | author1=Lockyer, C. | title=Age Determination by means of the ear plug in baleen whales | journal=Report of the International Whaling Commission | volume=34 | pages=692–696 | date=1984}}</ref> The oldest blue whale found was determined, using this method, to be 110 years old.<ref name=natgeo>{{cite magazine|magazine=]|title=Blue whale|url=https://www.nationalgeographic.com/animals/mammals/facts/blue-whale|archive-url=https://archive.today/20220607195937/https://www.nationalgeographic.com/animals/mammals/facts/blue-whale|archive-date=7 June 2022|access-date=2023-03-03}}</ref><ref name=wdc>{{cite web|title=Blue whale|work=]|url=https://us.whales.org/whales-dolphins/species-guide/blue-whale/|archive-url=https://archive.today/20230303051510/https://us.whales.org/whales-dolphins/species-guide/blue-whale/|archive-date=3 March 2023|access-date=2023-03-03}}</ref> The maximum age of a pygmy blue whale determined this way is 73 years.<ref name=Branch_2008>{{cite journal | author1=Branch, T. A. | title=Biological parameters for pygmy blue whales | journal=International Whaling Commission Document | volume=SC/60/SH6 | page=13 | date=2008}}</ref> In addition, female blue whales develop scars or ] on their ovaries every time they ovulate.<ref name=Perr_Donov_1984>{{cite book | last1=Perrin | first1=W. F. | last2=Donovan | first2=G. P. | chapter=Report of the Workshop | title=Reproduction in whales, dolphin and porpoises | location=Cambridge, UK | publisher=] | date=1984 | editor1-last=Perrin | editor1-first=W. F. | editor2-last=Donovan | editor2-first=G. P. | editor3-last=DeMaster | editor3-first=D. P.}}</ref> In a female pygmy blue whale, one corpus albicans is formed on average every 2.6 years.<ref name=Branch_2008/>
| title=The Whale bone Arch

| work = Places to Visit around the Isle of Lewis
==Behaviour and ecology==
| url=http://www.isle-of-lewis.com/places-to-visit.htm
]
| accessdate = 2005-05-18}}</ref>
The blue whale is usually solitary, but can be found in pairs. When productivity is high enough, blue whales can be seen in gatherings of more than 50 individuals.<ref name=Sears_Perr_2009/> Populations may go on long ], traveling to their summer feeding grounds towards the poles and then heading to their winter breeding grounds in more equatorial waters.<ref name=NOAAblue>{{cite web|url=https://www.fisheries.noaa.gov/species/blue-whale#overview | title=Blue Whale | publisher=NOAA Fisheries | access-date= 11 November 2019}}</ref> The animals appear to use memory to locate the best feeding areas.<ref>{{cite journal|author1=Abrahms, B.|author2=Hazen, E. L.|author3=Aikens, E. O.|author4=Savoca, M. S.|author5=Goldbogen, J. A.|author6=Goldbogen, S. J.|author7=Jacox, M. G.|author8=Irvine, L. M.|author9=Palacios, D. M.|author10=Mate, B. R.|year=2019|title=Memory and resource tracking drive blue whale migrations|journal=Proceedings of the National Academy of Sciences|volume=116|issue=12|pages=5582–5587|doi=10.1073/pnas.1819031116| pmid=30804188 | pmc=6431148 |bibcode=2019PNAS..116.5582A | doi-access=free }}</ref> There is evidence of alternative strategies, such as year-round residency, and partial (where only some individuals migrate) or age/sex-based migration. Some whales have been recorded feeding in breeding grounds.<ref name=Geijer_etal_2016>{{cite journal | author1=Geijer, C. K. | author2=Notarbartolo di Sciara, G. | author3=Panigada, S. | title=Mysticete migration revisited: Are Mediterranean fin whales an anomaly? | journal=Mammal Review | volume=46 | issue=4 | pages=284–296 | date=2016| doi=10.1111/mam.12069 }}</ref> The traveling speed for blue whales ranges {{convert|5|–|30|km/h|sp=us}}.<ref name=Sears_Perr_2009/> Their massive size limits their ability to ].<ref>{{cite journal|author1=Segre, P. S.|author2=Potvin, J|author3=Cade, D. E.|author4=Calambokidis, J|author5=Di Clemente , J|author6=Fish, F. E.|author7=Friedlaender, A. S.|author8=Gough, W. T.|author9=Kahane-Rapport, S. R.|author10=Oliveira, C|author11=Parks, S. E.|author12=Penry, G. S.|author13=Simon, M|author14=Stimpert, A. K.|author15=Wiley, D. N.|author16=Bierlich, K. C.|author17=Madsen, P. T.|author18=Goldbogen, J. A.|year=2020|title=Energetic and physical limitations on the breaching performance of large whales|journal=Physics of Living Systems|volume=9 |doi=10.7554/eLife.51760 |pmid=32159511 |pmc=7065846 |doi-access=free }}</ref>

The greatest dive depth reported from tagged blue whales was {{convert|315|m|sp=us}}.<ref name=Goldbogen_etal_2011/> Their theoretical aerobic dive limit was estimated at 31.2 minutes,<ref name=Croll_etal_2001>{{cite journal | author1=Croll, D. A. | author2=Aceveo-Gutierrez, A. | author3=Tershy, B. R. | author4=Urban-Ramirez, J. | title=The diving behavior of blue and fin whales: Is dive duration shorter than expected based on oxygen stores? | journal= Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology| volume=129 | issue=4 | pages=797–809 | date=2010| doi=10.1016/S1095-6433(01)00348-8 | pmid=11440866 }}</ref> however, the longest dive measured was 15.2 minutes.<ref name=Goldbogen_etal_2011/> The deepest confirmed dive from a pygmy blue whale was {{convert|506|m|sp=us}}.<ref name=Owen_etal_2016>{{cite journal | author1=Owen, K. | author2=Jenner, C. S. | author3=Jenner, M.-N. M. | author4=Andrews, R. D. | title=A week in the life of a pygmy blue whale: migratory dive depth overlaps with large vessel drafts | journal=Animal Biotelemetry | volume=4 | issue=17 | pages=1–11 | date=2016 | doi=10.1186/s40317-016-0109-4| doi-access=free | bibcode=2016AnBio...4...17O }}</ref> A blue whale's heart rate can drop to 2 beats per minute (bpm) at deep depths, but upon surfacing, can rise to 37 bpm, which is close to its peak heart rate.<ref>{{cite journal|author1=Goldbogen, J. A.|author2=Cade, D. E.|author3=Calambokidis, J.|author4=Czapanskiy, M. F.|author5=Fahlbusch, J.|author6=Friedlaender, A. S.|author7=Gough, W. T.|author8=Kahane-Rapport, S. R.|author9=Savoca, M. S.|author10=Ponganis, K. V.|author11=Ponganis, P. J.|year=2019|title=Extreme bradycardia and tachycardia in the world's largest animal|journal=Proceedings of the National Academy of Sciences|volume=116|issue=50|pages=25329–25332|doi=10.1073/pnas.1914273116| pmid=31767746 | pmc=6911174 |bibcode=2019PNAS..11625329G | doi-access=free }}</ref>

===Diet and feeding===
] of this blue whale is just visible on the far left.]]
The blue whale's diet consists almost exclusively of ].<ref name=Sears_Perr_2009/> Blue whales capture krill through lunge feeding; they swim towards them at high speeds as they open their mouths up to 80°.<ref name=Sears_Perr_2009/><ref name=Goldbogen_etal_2011/> They may engulf {{convert|220|t|sp=us}} of water at one time.<ref name=Fossette_etal_2017>{{cite journal | author1=Fossette, S. | author2=Abrahms, B. | author3=Hazen, E. L. | author4=Bograd, S. J. | author5=Zilliacus, K. M. | author6=Calambokidis, J. | author7=Burrows, J. A. | author8=Goldbogen, J. A. | author9=Harvey, J. T. | author10=Marinovic, B. | author11=Tershy, B. | author12=Croll, D. A. | title=Resource partitioning facilitates coexistence in sympatric cetaceans in the California Current | journal=] | volume=7 | issue=1 | pages=9085–9097 | date=2017| doi=10.1002/ece3.3409 | pmid=29152200 | pmc=5677487 | bibcode=2017EcoEv...7.9085F }}</ref> They squeeze the water out through their baleen plates with pressure from the throat pouch and tongue, and swallow the remaining krill.<ref name=Sears_Perr_2009/><ref name=Goldbogen_etal_2011>{{cite journal | author1=Goldbogen, J. A. | author2=Calambokidis, J. | author3=Oleson, E. | author4=Potvin, J.|author5-link=Nicholas Pyenson | author5=Pyenson, N. D. | author6=Schorr, G. | author7=Shadwick, R. E. | title=Mechanics, hydrodynamics and energetics of blue whale lunge feeding: Efficiency dependence on krill density | journal=Journal of Experimental Biology | volume=214 | issue=1 | pages=131–46 | date=2011| doi=10.1242/jeb.048157 | pmid=21147977 | doi-access=free | bibcode=2011JExpB.214..131G }}</ref> Blue whales have been recorded making 180° rolls during lunge-feeding, possibly allowing them to search the prey field and find the densest patches.<ref name=Goldbogen_etal_2012>{{cite journal | author1=Goldbogen, J. A. | author2=Calambokidis, J. | author3=Friedlaender, A. S. | author4=Francis, J. | author5=DeRuiter, A. L. | author6=Stimpert, A. K. | author7=Falcone, E. | author8=Southall, B. L. | title=Underwater acrobatics by the world's largest predator: 360° rolling manoeuvres by lunge-feeding blue whales | journal=] | volume=9 | issue=1 | doi=10.1098/rsbl.2012.0986 | pmid=23193050 | pmc=3565519 | page=20120986 | date=2012}}</ref>

While pursuing krill patches, blue whales maximize their calorie intake by increasing the number of lunges while selecting the thickest patches. This provides them enough energy for everyday activities while storing additional energy necessary for migration and reproduction. Due to their size, blue whales have larger energetic demands than most animals resulting in their need for this specific feeding habit.<ref>{{Cite web |last=Barlow |first=Dawn R. |date=2023 |title=Shaped by their Environment: Variation in Blue Whale Morphology Across Three Productive Coastal Ecosystems |url=https://academic.oup.com/iob/article/5/1/obad039/7438866 |access-date=November 23, 2024 |website=Integrative Organismal Biology}}</ref> Blue whales have to engulf densities greater than 100 krill/m<sup>3</sup> to maintain the cost of lunge feeding.<ref name=Goldbogen_etal_2011/><ref name=Hazen_etal_2015>{{cite journal | author1=Hazen, E. L. | author2=Friedlaender, A. S. | author3=Goldbogen, J. A. | title=Blue whales ("Balaenoptera musculus") optimize foraging efficiency by balancing oxygen use and energy gain as a function of prey density | journal=Science Advances | volume=1 | issue=9 | page=e1500469 | date=2015| bibcode=2015SciA....1E0469H | doi=10.1126/sciadv.1500469 | pmid=26601290 | pmc=4646804 | doi-access=free }}</ref> They can consume {{convert|34,776|–|1,912,680|kJ|kcal|sp=us}} from one mouthful of krill, which can provide up to 240 times more energy than used in a single lunge.<ref name=Goldbogen_etal_2011/> It is estimated that an average-sized blue whale must consume {{convert|1,120|±|359|kg|sp=us}} of krill a day.<ref name=Brodie_1975>{{cite journal | author1=Brodie, P. F. | title=Cetacean energetics, an overview of intraspecific size variation | journal=Ecology | volume=56 | issue=1 | pages=152–161 | date=1975| doi=10.2307/1935307 | jstor=1935307 | bibcode=1975Ecol...56..152B }}</ref><ref name=Croll_etal_2006>{{cite book | author1=Croll, D. A. | author2=Kudela, R. | author3=Tershy, B. R. | title=Whales, Whaling and Ocean Ecosystems | chapter=Ecosystem impact of the decline of large whales in the North Pacific | publisher=University of California Press | location=Berkeley, CA | editor1-last=Estes | editor1-first=J. A. | pages=202–214 | date=2006}}</ref>

In the southern ocean, blue whales feed on ] (''Euphausia superba''). In the South Australia, pygmy blue whales (''B. m. brevicauda'') feeds on '']''.<ref name=":1">{{Cite journal |last1=de Vos |first1=Asha |last2=Faux |first2=Cassandra E. |last3=Marthick |first3=James |last4=Dickinson |first4=Joanne |last5=Jarman |first5=Simon N. |date=2018-04-06 |title=New Determination of Prey and Parasite Species for Northern Indian Ocean Blue Whales |journal=Frontiers in Marine Science |language=English |volume=5 |doi=10.3389/fmars.2018.00104 |doi-access=free |issn=2296-7745}}</ref> In California, they feed mostly on ''],'' but also less commonly on North pacific krill ('']'').<ref>{{Cite journal |last1=Fiedler |first1=Paul C. |last2=Reilly |first2=Stephen B. |last3=Hewitt |first3=Roger P. |last4=Demer |first4=David |last5=Philbrick |first5=Valerie A. |last6=Smith |first6=Susan |last7=Armstrong |first7=Wesley |last8=Croll |first8=Donald A. |last9=Tershy |first9=Bernie R. |last10=Mate |first10=Bruce R. |date=1998-08-01 |title=Blue whale habitat and prey in the California Channel Islands |url=https://www.sciencedirect.com/science/article/abs/pii/S0967064598800179 |journal=Deep Sea Research Part II: Topical Studies in Oceanography |volume=45 |issue=8 |pages=1781–1801 |doi=10.1016/S0967-0645(98)80017-9 |bibcode=1998DSRII..45.1781F |issn=0967-0645}}</ref> Research of the Eastern North Pacific population shows that when diving to feed on krill, the whales reach an average depth of 201 meters, with dives lasting 9.8 minutes on average.<ref name=":1" />

While most blue whales feed almost exclusively on krill, the Northern Indian Ocean subspecies (''B. m. indica'') instead feeds predominantly on ] shrimp. To do so, they dive deeper and for longer periods of time than blue whales in other regions of the world, with dives of 10.7 minutes on average, and a hypothesized dive depth of about 300 meters. Fecal analysis also found the presence of fish, krill, ], ]s, and ] in their diet.<ref name=":1" />

Blue whales appear to avoid directly competing with other baleen whales.<ref name=Hardin_1960>{{cite journal | author1=Hardin, G. | s2cid=18542809 | title=The competitive exclusion principle | journal=Science | volume=131 | issue=3409 | pages=1292–1297 | date=1960| doi=10.1126/science.131.3409.1292 | pmid=14399717 | bibcode=1960Sci...131.1292H }}</ref><ref name=Hutchinson_1961>{{cite journal | author1=Hutchinson, G. E. | s2cid=86353285 | title=The Paradox of the Plankton | journal=] | volume=95 | issue=882 | pages=137–145 | date=1961| doi=10.1086/282171 | bibcode=1961ANat...95..137H }}</ref><ref name=Pianka_1974>{{cite journal | author1=Pianka, E. R. | title=Niche overlap and diffuse competition | journal=Proceedings of the National Academy of Sciences | volume=71 | issue=5 | pages=2141–2145 | date=1974| doi=10.1073/pnas.71.5.2141 | pmid=4525324 | pmc=388403 | bibcode=1974PNAS...71.2141P | doi-access=free }}</ref> Different whale species select different feeding spaces and times as well as different prey species.<ref name=Fossette_etal_2017/><ref name=Doniol-Valcroze_2008>{{cite thesis | author1=Doniol-Valcroze, T. | title=Habitat selection and niche characteristics of rorqual whales in the northern Gulf of St. Lawrence (Canada) | type=PhD | publisher=] | location=Montreal, Canada | date=2008}}</ref><ref name=Friedlaender_etal_2015>{{cite journal | author1=Friedlaender, A. S. | author2=Goldbogen, J. A. | author3=Hazen, E. L. | author4=Calambokidis, J. | author5=Southall, B. L. | title=Feeding performance by sympatric blue and fin whales exploiting a common prey resource | journal=Marine Mammal Science | volume=31 | issue=1 | pages=345–354 | date=2015| doi=10.1111/mms.12134 | bibcode=2015MMamS..31..345F }}</ref> In the ], baleen whales appear to feed on ] of different sizes, which may lessen competition between them.<ref name=Santora_etal_2010>{{cite journal | author1=Santora, J. A. | author2=Reiss, C. S. | author3=Loeb, V. J. | author4=Veit, R. R. | title=Spatial association between hotspots of baleen whales and demographic patterns of Antarctic krill ''Euphausia superba'' suggests size-dependent predation | journal=Marine Ecology Progress Series | volume=405 | pages=255–269 | date=2010| doi=10.3354/meps08513 | bibcode=2010MEPS..405..255S | doi-access=free }}</ref>

Blue whale feeding habits may differ due to situational disturbances, like environmental shifts or human interference. This can cause a change in diet due to stress response. Due to these changing situations, there was a study performed on Blue whales measuring Cortisol levels and comparing them with the levels of stressed individuals, it gave a closer look to the reasoning behind their diet and behavioral changes.<ref>{{Cite web |last=Melica |first=Valentina |date=2020 |title=Reproduction and Stress Response Endocrinology in Blue (Balaenoptera musculus) and Gray (Eschrichtius robust) Whales |url=https://scholarworks.alaska.edu/bitstream/handle/11122/12414/Melica_V_2020.pdf |access-date=November 23, 2024 |website=Scholarworks Alaska}}</ref>

===Reproduction and birth===
]
Blue whales generally reach sexual maturity at 8–10 years. In the Northern Hemisphere, the length at which they reach maturity is {{convert|21|–|23|m|sp=us}} for females and {{convert|20|–|21|m|sp=us}} for males. In the Southern Hemisphere, the length of maturity is {{convert|23|–|24|m|sp=us}} and {{convert|22|m|sp=us}} for females and males respectively.<ref name=Sears_Perrin_2018>{{cite book | author1=Sears, R. | author2=Perrin, W. F. | title=Encyclopedia of marine mammals | chapter=Blue Whale: "Balaenoptera musculus" | publisher=Academic Press | location=London, UK | editor1-last=Würsig | editor1-first=B. | editor2-last=Thewissen | editor2-first=J. G. M. | editor3-last=Kovacs | editor3-first=K. M. | pages=110–114 | date=2018}}</ref> Male pygmy blue whales average {{convert|61.4|ft|order=flip|sp=us}} at sexual maturity.<ref name=Ichihara_1964>{{cite journal | author1=Ichihara T. | title=The pygmy blue whale, ''Balaenoptera musculus brevicauda'', a new subspecies from Antarctic | journal=Norsk. Hvalf. Tid. | volume=6 | date=1964}}</ref><ref name=Sazhinov_1970>{{cite journal | author1=Sazhinov E. G. | title=The onset of sexual and physical maturity for pygmy blue whales (''Balaenoptera musculus brevicauda''. Ichinara. 1966) | journal=Whales of the Southern Hemisphere | issue=29 | pages=34–40 | date=1970}}</ref> Female pygmy blue whales are {{convert|68.9|–|71.2|ft|order=flip|sp=us}} in length<ref name=Branch_2007a/> and roughly 10 years old at the age of sexual maturity.<ref name=Branch_2007a/><ref name=Gilpatrick_Perryman_2008/><ref name=Branch_Mikhalev_2008>{{cite journal | author1=Branch, T. A. | author2=Mikhalev, Y. A. | title=Regional differences in length at sexual maturity for female blue whales based on recovered Soviet whaling data | journal=Marine Mammal Science | volume=24 | issue=3 | pages=690–703 | date=2008| doi=10.1111/j.1748-7692.2008.00214.x | bibcode=2008MMamS..24..690B }}</ref> Little is known about mating behavior, or breeding and birthing areas.<ref name=Mizroch_1984/><ref name=Sears_Perrin_2018/> Blue whales appear to be ], with males competing for females.<ref name=Sears_Perrin_2018/><ref name=Sears_etal_2013>{{cite journal | author1=Sears, R. | author2=Ramp, C. | author3=Douglas, A. B. | author4=Calambokidis, J. | title=Reproductive parameters of eastern North Pacific blue whales ''Balaenoptera musculus'' | journal=Endangered Species Research | volume=22 | issue=1 | pages=23–31 | date=2013| doi=10.3354/esr00532 | doi-access=free }}</ref> A male blue whale typically trails a female and will fight off potential rivals.<ref name=Schall_etal_2019>{{cite journal | author1=Schall, E. | author2=Di Lorio, L. | author3=Berchok, C. | author4=Filún, D. | author5=Bedriñana-Romano, L. | author6=Buchan, S. J. | author7=Van Opzeeland, I. | author8=Sears, R. | author9=Hucke-Gaete, R. | title=Visual and passive acoustic observations of blue whale trios from two distinct populations | journal=Marine Mammal Science | volume=36 | issue=1 | doi=10.1111/mms.12643 | pages=365–374 | date=2019| doi-access=free | hdl=1912/24953 | hdl-access=free }}</ref> The species mates from fall to winter.<ref name=Mizroch_1984/><ref name=Sears_Perrin_2018/>

Pregnant females eat roughly four percent of their body weight daily,<ref name=Sergeant_1969>{{cite journal | author1=Sergeant, D. E. | title=Feeding rates of Cetacea | journal=Fiskeridir. SKR. Havundersok | volume=15 | pages=246–258 | date=1969}}</ref> amounting to 60% of their overall body weight throughout summer foraging periods.<ref name=Sears_Perrin_2018/><ref name=Lockyer_1984b>{{cite journal | author1=Lockyer, C. | title=Review of baleen whale (Mysticeti) reproduction and implications for management | journal=Report of the International Whaling Commission | volume=6 | pages=27–50 | date=1984}}</ref> ] may last 10–12 months with calves being {{convert|6|–|7|m|sp=us}} long and weighing {{convert|2|–|3|t|sp=us}} at birth.<ref name=Sears_Perrin_2018/> Estimates suggest that because calves require {{convert|2|-|4|kg|sp=us}} milk per kg of mass gain, blue whales likely produce {{convert|220|kg|sp=us}} of milk per day (ranging from {{convert|110|to|320|kg|sp=us}} of milk per day).<ref name=Oftedal_1997>{{cite journal | author1=Oftedal, O. T. | s2cid=19588882 | title=Lactation in whales and dolphins: Evidence of divergence between baleen- and toothed-species | journal=Journal of Mammary Gland Biology and Neoplasia | volume=2 | issue=3 | pages=205–230 | date=1997| doi=10.1023/A:1026328203526 | pmid=10882306 }}</ref> The first video of a calf thought to be nursing was filmed in New Zealand in 2016.<ref>{{cite web | url=https://www.nationalgeographic.com/news/2016/03/160302-blue-whale-mother-calf-nursing-video-pygmy-new-zealand/ | archive-url=https://web.archive.org/web/20191231040656/https://www.nationalgeographic.com/news/2016/03/160302-blue-whale-mother-calf-nursing-video-pygmy-new-zealand/ | url-status=dead | archive-date=31 December 2019 | title=Exclusive Video May Show Blue Whale Calf Nursing | date=2 March 2016 | publisher=] | access-date=20 December 2019}}</ref> Calves may be ] when they reach 6–8 months old at a length of {{convert|53|ft|order=flip|sp=us}}.<ref name=Sears_Perrin_2018/> They gain roughly {{convert|37,500|lb|sp=us}} during the weaning period.<ref name=Lockyer_1981/> Interbirth periods last two to three years;<ref name=Sears_Perrin_2018/> they average 2.6 years in pygmy blue whales.<ref name=Branch_2008/>


===Vocalizations=== ===Vocalizations===
{{listen
{{See also|Whale song}}
| pos = right
{| class="infobox" style="" width="25%"
|- style="text-align: center;"
|'''Multimedia relating to the blue whale'''<br /><div class="small">''Note that the whale calls have been sped up 10x from their original speed.''</div>
|-
|{{listen
| filename = Blue whale atlantic1.ogg | filename = Blue whale atlantic1.ogg
| title = A blue whale song | title = A blue whale song
| description = Recorded in the Atlantic (1) | description = Recorded in the Atlantic (1)
| format = ] | format = ]
| filename2 = Blue whale atlantic2.ogg | filename2 = Blue whale atlantic3.ogg
| title2 = A blue whale song | title2 = A blue whale song
| description2 = Recorded in the Atlantic (2) | description2 = Recorded in the Atlantic (2)
| format2 = ] | format2 = ]
| filename3 = Blue whale atlantic3.ogg | filename3 = Blue_Whale_NE_Pacific.ogg
| title3 = A blue whale song | title3 = A blue whale song
| description3 = Recorded in the Atlantic (3) | description3 = Recorded in North Eastern Pacific
| format3 = ] | format3 = ]
| filename4 = Blue_Whale_NE_Pacific.ogg | filename4 = Blue_Whale_South_Pacific.ogg
| title4 = A blue whale song | title4 = A blue whale song
| description4 = Recorded in North Eastern Pacific | description4 = Recorded in the South Pacific
| format4 = ] | format4 = ]
| filename5 = Blue_Whale_South_Pacific.ogg | filename5 = Blue_Whale_West_Pacific.ogg
| title5 = A blue whale song | title5 = A blue whale song
| description5 = Recorded in the South Pacific | description5 = Recorded in the West Pacific
| format5 = ] | format5 = ]
| filename6 = Blue_Whale_West_Pacific.ogg
| title6 = A blue whale song
| description6 = Recorded in the West Pacific
| format6 = ]
}} }}
Blue whales produce some of the loudest and lowest ] vocalizations in the animal kingdom,<ref name=NOAA/> and their inner ears appear well adapted for detecting ] sounds.<ref name=Yamato_etal_2008>{{cite journal | author1=Yamato, M. | author2=Ketten, D. R. | author3=Arruda, J. | author4=Cramer, S. | title=Biomechanical and structural modeling of hearing in baleen whales | journal=Bioacoustics | volume=17 | issue=1–3 | pages=100–102 | date=2008| doi=10.1080/09524622.2008.9753781 | bibcode=2008Bioac..17..100Y | s2cid=85314872 }}</ref> The ] for blue whale ] ranges from 8 to 25&nbsp;Hz.<ref name=Stafford_etal_1998>{{cite journal | author1=Stafford, K. M. | author2=Fox, G. C. | author3=Clark, D. S. | title=Long-range acoustic detection and localization of blue whale calls in the northeast Pacific Ocean | journal=Journal of the Acoustical Society of America | volume=50 | issue=4 | pages=1193–1198 | date=1998| bibcode=1998ASAJ..104.3616S | doi=10.1121/1.423944 | pmid=9857519 }}</ref> Blue whale songs vary between populations.<ref name=McDonald_etal_2006>{{cite journal | author1=McDonald, M. A. | author2=Mesnick, S. L. | author3=Hildebrand, J. A. | title=Biogeographic characterization of blue whale song worldwide: Using song to identify populations | journal=Journal of Cetacean Research and Management | volume=8 | pages=55–66 | date=2023| doi=10.47536/jcrm.v8i1.702 | s2cid=18769917 | doi-access=free }}</ref>
|}
Estimates made by Cummings and Thompson (1971) suggest that source level of sounds made by blue whales are between 155 and 188 ]s when measured relative to a reference pressure of one ] at one metre.<ref>{{cite journal
| title = Underwater sounds from the blue whale ''Balaenoptera musculus''
| author = W.C. Cummings and P.O. Thompson
| journal = Journal of the Acoustics Society of America
| volume = 50(4)
| pages = 1193–1198
| year = 1971
| doi = 10.1121/1.1912752}}</ref><ref>{{cite book
| author= W.J. Richardson, C.R. Greene, C.I. Malme and D.H. Thomson
| title = Marine mammals and noise
| publisher = Academic Press, Inc., San Diego, CA.
| year = 1995
| isbn = 0-12-588441-9}}</ref> All blue whale groups make calls at a ] of between 10 and 40 ]; the lowest frequency sound a human can typically perceive is 20&nbsp;Hz. Blue whale calls last between ten and thirty seconds. Blue whales off the coast of ] have been repeatedly recorded making "songs" of four notes duration lasting about two minutes each, reminiscent of the well-known ]. Researchers believe that as this phenomenon has not been seen in any other populations, it may be unique to the ''B. m. brevicauda'' (Pygmy) subspecies.


Vocalizations produced by the Eastern North Pacific population have been well studied. This population produces pulsed calls ("A") and tonal calls ("B"), upswept tones that precede type B calls ("C") and separate downswept tones ("D").<ref name=Aroyan_etal_2000>{{cite book | author1=Aroyan, J. L. | author2=McDonald, M. A. | author3=Webb, S. C. | author4=Hildebrand, J. A. | author5=Clark, D. S. | author6=Laitman, J. T. | author7=Reidenberg, J. S. | title=Hearing by whales and dolphins | chapter=Acoustic models of sound production and propagation | editor1-last=Au | editor1-first=W. W. A. | editor2-last=Popper | editor2-first=A. | editor3-last=Fay | editor3-first=R. N. | publisher=Springer-Verlag | location=New York | page=442 | date=2000}}</ref><ref name=McDonald_etal_2001>{{cite journal | author1=McDonald, M. A. | author2=Calambokidis, J. | author3=Teranishi, A. M. | author4=Hildebrand, J. A. | title=The acoustic calls of blue whales off California with gender data | journal=Journal of the Acoustical Society of America | volume=109 | issue=4 | pages=1728–1735 | date=2001| doi=10.1121/1.1353593 | pmid=11325141 | bibcode=2001ASAJ..109.1728M | url=http://www.escholarship.org/uc/item/6vg9t2g7 }}</ref> A and B calls are often produced in repeated co-occurring sequences and sung only by males, suggesting a reproductive function.<ref name=McDonald_etal_2001/><ref name=Oleson_etal_2007a>{{cite journal | author1=Oleson, E. M. | author2=Calambokidis, J. | author3=Burgess, W. C. | author4=McDonald, M. A. | author5=LeDuc, C. A. | author6=Hildebrand, J. A. | title=Behavioral context of call production by eastern North Pacific blue whales | journal= ]| volume=330 | pages=269–284 | date=2007| doi=10.3354/meps330269 | bibcode=2007MEPS..330..269O | doi-access=free }}</ref> D calls may have multiple functions. They are produced by both sexes during social interactions while feeding.<ref name=Oleson_etal_2007a/><ref name=Lewis_etal_2018>{{cite journal | author1=Lewis, L. A. | author2=Calambokidis, J. | author3=Stimpert, A. K. | author4=Fahlbusch, J. | author5=Friedlaender, A. S. | author6=McKenna, M. F. | author7=Mesnick, S. | author8=Oleson, E. M. | author9=Southall, B. L. | author10=Szesciorka, A. S. | author11=Sirovic, A. | title=Context-dependent variability in blue whale acoustic behaviour | journal=] | volume=5 | issue=8 | page=1080241 | date=2018 | doi=10.1098/rsos.180241| pmid=30225013 | pmc=6124089 }}</ref> and by males when competing for mates.<ref name=Schall_etal_2019/>
The reason for vocalization is unknown. Richardson ''et al.'' (1995) discuss six possible reasons:<ref>{{cite web
| author = National Marine Fisheries Service
| year = 2002
| title = Endangered Species Act - Section 7 Consultation Biological Opinion
| url = http://www.nmfs.noaa.gov/prot_res/readingrm/ESAsec7/7pr_surtass-2020529.pdf
| format = PDF }}</ref>


Blue whale calls recorded off Sri Lanka have a three-unit phrase. The first unit is a 19.8 to 43.5&nbsp;Hz pulsive call, and is normally 17.9 ± 5.2 seconds long. The second unit is a 55.9 to 72.4&nbsp;Hz ] upsweep that is 13.8 ± 1.1 seconds long. The final unit is 28.5 ± 1.6 seconds long with a tone of 108 to 104.7&nbsp;Hz.<ref name=Stafford_etal_2010>{{cite journal | author1=Stafford, K. M. | author2=Chapp, E. | author3=Bohnenstiel, D. | author4=Tolstoy, M. | author4-link=Maya Tolstoy | title=Seasonal detection of three types of "pygmy" blue whale calls in the Indian Ocean | journal=Marine Mammal Science | volume=27 | issue=4 | pages=828–840 | date=2010| doi=10.1111/j.1748-7692.2010.00437.x }}</ref> A blue whale call recorded off Madagascar, a two-unit phrase,<ref name=Ljungblad_etal_1998>{{cite report | author1=Ljungblad, D. K. | author2=Clark, C. W. | author3=Shimada, H. | title=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 | publisher=International Whaling Commission | volume=48 | pages=439–442 | date=1998}}</ref> consists of 5–7 pulses with a ] of 35.1 ± 0.7&nbsp;Hz lasting 4.4 ± 0.5 seconds proceeding a 35 ± 0&nbsp;Hz tone that is 10.9 ± 1.1 seconds long.<ref name=Stafford_etal_2010/> In the Southern Ocean, blue whales produce 18-second vocals which start with a 9-second-long, 27&nbsp;Hz tone, and then a 1-second downsweep to 19&nbsp;Hz, followed by a downsweep further to 18&nbsp;Hz.<ref name=Sirovic_etal_2004>{{cite journal | author1=Sirovic, A. | author2=Hildebrand, J. A. | author3=Wiggins, S. M. | author4=McDonald, M. A. | author5=Moore, S. E. | author6=Thiele, D. | title=Seasonality of blue and fin whale calls and the influence of sea ice in the Western Antarctic Peninsula | journal=] | volume=51 | issue=17–19 | pages=2327–2344 | date=2004| doi=10.1016/j.dsr2.2004.08.005 | bibcode=2004DSRII..51.2327S }}</ref><ref name=Rankin_etal_2005/> Other vocalizations include 1–4 second long, frequency-modulated calls with a frequency of 80 and 38&nbsp;Hz.<ref name=Rankin_etal_2005>{{cite journal | author1=Rankin, S. | author2=Ljungblad, D. | author3=Clark, C. | author4=Kato, H. | title=Vocalisations of Antarctic blue whales, ''Balaenoptera musculus intermedia'', recorded during the 2001/2002 and 2002/2003 IWC/SOWER circumpolar cruises, Area V, Antarctica | journal=Journal of Cetacean Research and Management | volume=7 | pages=13–20 | date=2023| doi=10.47536/jcrm.v7i1.752 | s2cid=43993242 | doi-access=free }}</ref><ref name=Sirovic_etal_2006>{{cite journal | author1=Sirovic, A. | author2=Hildebrand, J. A. | author3=Thiele, D. | title=Baleen whales in the Scotia Sea in January and February 2003 | journal=Journal of Cetacean Research and Management | volume=8 | pages=161–171 | date=2006| doi=10.47536/jcrm.v8i2.712 | s2cid=251277044 | doi-access=free }}</ref>
# Maintenance of inter-individual distance
# Species and individual recognition
# Contextual information transmission (e.g., feeding, alarm, courtship)
# Maintenance of social organization (e.g., contact calls between females and males)
# Location of topographic features
# Location of prey resources


There is evidence that some blue whale songs have temporally declined in tonal frequency.<ref name=Nieukirk_etal_2005>{{cite conference | author1=Nieukirk, S. L. | author2=Mellinger, D. K. | author3=Hildebrand, J. A. | author4=McDonald, M. A. | author5=Dziak, R. P. | title=Downward shift in the frequency of blue whale vocalizations | conference=16th Biennial Conference on the Biology of Marine Mammals | location=San Diego, CA | page=205 | date=2005}}</ref><ref name=McDonald_etal_2009>{{cite journal | author1=McDonald, M. A. | author2=Hildebrand, J. A. | author3=Mesnick, S. | title=Worldwide decline in tonal frequencies of blue whale songs | journal=Endangered Species Research | volume=9 | pages=13–21 | date=2009| doi=10.3354/esr00217 | doi-access=free }}</ref><ref name=Leroy_etal_2018>{{cite journal | author1=Leroy, E. C. | author2=Royer, J.-Y. | author3=Bonnel, J. | author4=Samaran, F. | title=Long-term and seasonal changes of large whale call frequency in the southern Indian Ocean | journal=] | volume=123 | issue=11 | pages=8568–8580 | date=2018| doi=10.1029/2018JC014352 | bibcode=2018JGRC..123.8568L | s2cid=135201588 | url=https://archimer.ifremer.fr/doc/00516/62730/ | doi-access=free | hdl=1912/10837 | hdl-access=free }}</ref> The vocalization of blue whales in the Eastern North Pacific decreased in tonal frequency by 31% from the early 1960s to the early 21st century.<ref name=Nieukirk_etal_2005/><ref name=McDonald_etal_2009/> The frequency of pygmy blue whales in the Antarctic has decreased by a few tenths of a hertz every year starting in 2002.<ref name=Leroy_etal_2018/> It is possible that as blue whale populations recover from whaling, there is increasing sexual selection pressure (i.e., a lower frequency indicates a larger body size).<ref name=McDonald_etal_2009/>
==Population and whaling==
===Hunting era===
{{Main|History of whaling}}
]


===Predators and parasites===
Blue whales are not easy to catch or kill. Their speed and power meant that they were rarely pursued by early whalers, who instead targeted ] and ]s.<ref>{{cite book
The only known natural predator to blue whales is the ], although the rate of fatal attacks by orcas is unknown. Photograph-identification studies of blue whales have estimated that a high proportion of the individuals in the ] have rake-like scars, indicative of encounters with orcas.<ref name=Sears_1990>{{cite journal | author1=Sears, R. | title=The Cortez blues | journal=Whalewatcher | volume=24 | pages=12–15 | date=1990}}</ref> Off southeastern ], 3.7% of blue whales photographed had rake marks and 42.1% of photographed pygmy blue whales off Western Australia had rake marks.<ref name=Mehta_etal_2007>{{cite journal | author1=Mehta, A. V. | author2=Allen, J. M. | author3=Constantine, R. | author4=Garrigue, C. | author5=Jann, B. | author6=Jenner, C. | author7=Marx, M. K. | author8=Matkin, C. O. | author9=Mattila, D. K. | author10=Minton, G. | author11=Mizroch, S. A. | author12=Olavarría, C. | author13=Robbins, J. | author14=Russell, K. G. | author15=Seton, R. E. | title=Baleen whales are not important as prey for orcas (''Orcinus orca'') in high latitudes | journal=Marine Ecology Progress Series | volume=348 | pages=297–307 | date=2007| doi=10.3354/meps07015 | doi-access=free | hdl=1912/4520 | hdl-access=free }}</ref> Documented ] by orcas has been rare. A blue whale mother and calf were first observed being chased at high speeds by orcas off southeastern Australia.<ref name=Cotton_1944>{{cite journal | author1=Cotton, B. C. | title=Killer whales in South Australia | journal=] | volume=10 | pages=293–294 | date=1944}}</ref> The first documented attack occurred in 1977 off southwestern ], but the injured whale escaped after five hours.<ref name=Tarpy_1979>{{cite journal | author1=Tarpy, C. | title=Killer whale attack! | journal=National Geographic Magazine | volume=155 | pages=542–545| date=1979}}</ref> Four more blue whales were documented as being chased by a group of orcas between 1982 and 2003.<ref name=Ford_Reeves_2008>{{cite journal | author1=Ford, J. K. B. | author2=Reeves, R. | title=Fight or flight: antipredator strategies of baleen whales | journal=] | volume=38 | issue=1 | pages=50–86 | date=2008| doi=10.1111/j.1365-2907.2008.00118.x }}</ref> The first documented predation event by orcas occurred in September 2003, when a group of orcas in the ] was encountered feeding on a recently killed blue whale calf.<ref name=Pitman_etal_2007>{{cite journal | author1=Pitman, R. | author2=Fearnbach, H. | author3=LeDuc, R. | author4=Gilpatrick, J. W. | author5=Ford, J. K. B. | author6=Balance, L. T. | title=Killer whales preying on a blue whale calf on the Costa Rica Dome: Genetics, morphometrics, vocalizations and composition of the group | journal=Journal of Cetacean Research and Management | volume=9 | pages=151–158 | date=2023| issue=2 | doi=10.47536/jcrm.v9i2.683 | s2cid=257138804 | doi-access=free }}</ref> In March 2014, a commercial whale watch boat operator recorded an incident involving a group of orcas harassing a blue whale in ]. The blue whale defended itself by slapping its tail.<ref>{{cite web | url=https://www.livescience.com/43879-killer-whales-attack-blue-whale-video.html | title=Killer Whales Bully Lone Blue Whale in Rare Video | date=5 March 2014 | publisher=] | access-date=23 December 2019}}</ref> A similar incident was recorded by a drone in Monterey Bay in May 2017.<ref>{{cite web | url=https://www.nationalgeographic.com/news/2017/05/killer-whale-attacks-blue-whale-monterey-drone-video | archive-url=https://web.archive.org/web/20191231040658/https://www.nationalgeographic.com/news/2017/05/killer-whale-attacks-blue-whale-monterey-drone-video/ | url-status=dead | archive-date=31 December 2019 | title=Killer Whales Attacked a Blue Whale—Here's the Surprising Reason Why | date=25 May 2017 | publisher=National Geographic | access-date=23 December 2019}}</ref> The first direct observations of orca predation occurred off the south coast of Western Australia, two in 2019 and one more in 2021. The first victim was estimated to be {{convert|18|–|22|m|sp=us}}.<ref>{{cite journal|author1=Totterdell, J. A.|author2=Wellard, R.|author3=Reeves, I. M.|author4=Elsdon, B.|author5=Markovic, P.|author6=Yoshida, M.|author7=Fairchild, A.|author8=Sharp, G.|author9=Pitman, R.|year=2022|title=The first three records of killer whales (''Orcinus orca'') killing and eating blue whales (''Balaenoptera musculus'')|journal=Marine Mammal Science|volume=38 |issue=3 |pages=1286–1301 |doi=10.1111/mms.12906|bibcode=2022MMamS..38.1286T | s2cid=246167673 }}</ref>
|author= Scammon CM
|title=The marine mammals of the northwestern coast of North America. Together with an account of the American whale-fishery
|year= 1874
|publisher=John H. Carmany and Co.
|location=San Francisco
|page=319
|isbn= }}</ref> In 1864, the Norwegian ] equipped a ] with ]s specifically designed for catching large whales.<ref name="factsheet" /> Although initially cumbersome and with a low success rate, Foyn perfected the harpoon gun, and soon several whaling stations were established on the coast of ] in northern ]. Because of disputes with the local fishermen, the last whaling station in Finnmark was closed down in 1904.


In Antarctic waters, blue whales accumulate diatoms of the species ''] ceticola'' and the genera '']'', which are normally removed when the whales enter warmer waters. Other external parasites include ]s such as '']'', '']'', and '']'', which latch on their skin deep enough to leave behind a pit if removed. ] species make their home in cracks of the skin and are relatively harmless. The ] species '']'' digs in and attaches itself to the blubber to feed on. Intestinal parasites include the ] genera '']'' and '']''; the ] genera '']'', '']'', '']'', '']'', and '']''; and the ] genus '']''. In the North Atlantic, blue whales also contain the protozoans '']'', '']'' and '']''.<ref>{{cite journal|last1=Hermosilla|first1=C|last2=Silva|first2=L. M. R.|last3=Prieto|first3=R|last4=Kleinertz|first4=S|last5=Taubert|first5=A|last6=Silva|first6=M. A.|year=2015|title=Endo- and ectoparasites of large whales (Cetartiodactyla: Balaenopteridae, Physeteridae): Overcoming difficulties in obtaining appropriate samples by non- and minimally-invasive methods|journal=International Journal for Parasitology: Parasites and Wildlife|volume=4|issue=3|pages=414–420|doi=10.1016/j.ijppaw.2015.11.002|pmid=26835249|pmc=4699982|bibcode=2015IJPPW...4..414H}}</ref>
Soon, blue whales were being hunted in ] (1883), the ] (1894), ] (1898), and ] (1903). In 1904-05 the first blue whales were taken off ]. By 1925, with the advent of the stern slipway in factory ships and the use of steam-driven whale catchers, the catch of blue whales, and baleen whales as a whole, in the Antarctic and sub-Antarctic began to increase dramatically. Between 1930 and 1931, these ships killed 29,400 blue whales in the Antarctic alone. By the end of ], populations had been significantly depleted, and, in 1946, the first quotas restricting international trade in whales were introduced, but they were ineffective because of the lack of differentiation between species. Rare species could be hunted on an equal footing with those found in relative abundance.


==Conservation==
Blue whale hunting was banned in the 1960s by the ],<ref>{{cite journal
The global blue whale population is estimated to be 5,000–15,000 mature individuals and 10,000–25,000 total as of 2018. By comparison, there were at least 140,000 mature whales in 1926. There are an estimated total of 1,000–3,000 whales in the North Atlantic, 3,000–5,000 in the North Pacific, and 5,000–8,000 in the Antarctic. There are possibly 1,000–3,000 whales in the eastern South Pacific while the pygmy blue whale may number 2,000–5,000 individuals.<ref name="iucn"/> Blue whales have been protected in areas of the Southern Hemisphere since 1939. In 1955, they were given complete protection in the North Atlantic under the ]; this protection was extended to the Antarctic in 1965 and the North Pacific in 1966.<ref name=Gambell_1979>{{cite journal | author1=Gambell, R. | title=The blue whale | journal=Biologist | volume=26 | pages=209–215 | date=1979}}</ref><ref name=Best_1993>{{cite journal | author1=Best, P. B. | title=Increase rates in severely depleted stocks of baleen whales | journal=ICES J. Mar. Sci. | volume=50 | issue=2 | pages=169–186 | date=1993| doi=10.1006/jmsc.1993.1018 | bibcode=1993ICJMS..50..169B }}</ref> The protected status of North Atlantic blue whales was not recognized by Iceland until 1960.<ref name="Sigurjónsson_1988">{{cite journal | author1=Sigurjónsson, J. | title=Operational factors of the Icelandic large whale fishery | journal=Reports of the International Whaling Commission| volume=38 | pages=327–333 | date=1988}}</ref> In the United States, the species is protected under the ].<ref name=NOAAblue/>
|last=Gambell
|first=R
|year= 1979
|title=The blue whale
|journal= Biologist
|volume= 26
|pages=209–215}}</ref><ref>{{cite journal
|last=Best
|first=PB
|year=1993
|month=
|title=Increase rates in severely depleted stocks of baleen whales
|journal=ICES J. Mar. Sci.
|volume=50
|pages=169–186
|doi=10.1006/jmsc.1993.1018}}</ref> and illegal whaling by the USSR finally halted in the 1970s,<ref>{{cite journal
|last=Yablokov
|first=AV
|year=1994
|title=Validity of whaling data
|journal=Nature
|volume=367
|issue=
|pages=108
|doi=10.1038/367108a0}}</ref> by which time 330,000 blue whales had been killed in the Antarctic, 33,000 in the rest of the Southern Hemisphere, 8,200 in the North Pacific, and 7,000 in the North Atlantic. The largest original population, in the Antarctic, had been reduced to 0.15% of their initial numbers.<ref name=Ant/>


Blue whales are formally classified as ] under both the U.S. ]<ref>{{cite web |url=https://ecos.fws.gov/docs/federal_register/fr21.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://ecos.fws.gov/docs/federal_register/fr21.pdf |archive-date=9 October 2022 |url-status=live |title=Part 17 – Conservation of Endangered Species and Other Fish or Wildlife (First List of Endangered Foreign Fish and Wildlife as Appendix A) | date=2 June 1970 |publisher=] |access-date=24 December 2019}}</ref> and the ].<ref name="iucn"/> They are also listed on Appendix&nbsp;I under the ] (CITES)<ref>{{cite web | url=https://www.cites.org/eng/app/appendices.php | title=Appendices | date=26 November 2019 | publisher=Convention on International Trade in Endangered Species of Wild Fauna and Flora | access-date=24 December 2019}}</ref> and the ].<ref>{{cite web | url=https://www.cms.int/sites/default/files/instrument/CMS-text.en_.PDF | title=Convention on the Conservation of Migratory Species of Wild Animals | date=23 June 1979 | publisher=] | access-date=24 December 2019 | archive-url=https://web.archive.org/web/20200502225536/https://www.cms.int/sites/default/files/instrument/CMS-text.en_.PDF | archive-date=2 May 2020 | url-status=dead }}</ref> Although, for some populations, there is not enough information on current abundance trends (e.g., pygmy blue whales), others are ] (e.g., Antarctic blue whales).<ref name=Samaran_etal_2013>{{cite journal | author1=Samaran, F. | author2=Stafford, K. M. | author3=Branch, T. A. | author4=Gedamke, J. | author5=Royer, Y.-J. | author6=Dziak, R. P. | author7=Guinet, C. | title=Seasonal and geographic variation of southern blue whale subspecies in the Indian Ocean | journal=PLOS ONE | volume=8 | issue=8 | page=e71561 | date=2013| bibcode=2013PLoSO...871561S | doi=10.1371/journal.pone.0071561 | pmid=23967221 | pmc=3742792 | doi-access=free }}</ref><ref>{{cite web | url=https://iucn-csg.org/35-updated-cetacean-red-list-assessments-published-in-nov-2018/ | title=Blue Whale | date=6 December 2018 | publisher=International Union for Conservation | access-date= 24 December 2019}}</ref>
===Population and distribution today===
]]]
] in the background, August 2007]]


===Threats===
Since the introduction of the whaling ban, studies have failed to ascertain whether the ] global blue whale population is increasing or remaining stable. In the Antarctic, best estimates show a significant increase at 7.3% per year since the end of illegal Soviet whaling, but numbers remain at under 1% of their original levels.<ref name=Ant/> It has also been suggested that Icelandic and Californian populations are increasing but these increases are not statistically significant. The total world population was estimated to be between 5,000 and 12,000 in 2002, although there are high levels of uncertainty in available estimates for many areas.<ref name=pop/>
] platform]]
Blue whales were initially difficult to hunt because of their size and speed.<ref name=NOAA/> This began to change in the mid-19th century with the development of harpoons that can be shot as projectiles.<ref>{{cite book |author=Darby, Andrew |url=https://archive.org/details/harpoonintoheart00darb/page/38/mode/2up |title=Harpoon Into the Heart of Whaling |publisher=Hachette Books |year=2009 |isbn=9780786732005 |pages=38–39 |url-access=registration}}</ref> Blue whale whaling peaked between 1930 and 1931 with 30,000 animals taken. Harvesting of the species was particularly high in the Antarctic, with 350,000–360,000 whales taken in the first half of the 20th century. In addition, 11,000 North Atlantic whales (mostly around Iceland) and 9,500 North Pacific whales were killed during the same period.<ref name=Sears_Perrin_2018/> The International Whaling Commission banned all hunting of blue whales in 1966 and gave them worldwide protection.<ref>{{cite web|title=Blue whale – ''Balaenoptera musculus''|publisher=International Whaling Commission|access-date=25 February 2022|url=https://iwc.int/blue-whale}}</ref> However, the ] continued to illegally hunt blue whales and other species up until the 1970s.<ref>{{cite journal|author1=Ivashchenko, Y.|author2=Clapham, P. J.|author3=Brownell, R.|year=2011|title=Soviet Illegal Whaling: The Devil and the Details|journal=Marine Fisheries Review|volume=73|issue=1|pages=1–19|url=https://aquadocs.org/bitstream/handle/1834/26267/mfr7331.pdf?sequence=1&isAllowed=y|access-date=26 January 2023|archive-date=22 March 2022|archive-url=https://web.archive.org/web/20220322075344/https://aquadocs.org/bitstream/handle/1834/26267/mfr7331.pdf?sequence=1&isAllowed=y}}</ref>
]
] are a significant mortality factor for blue whales, especially off the ].<ref name="Berman-Kowalewski_etal_2010">{{cite journal | author1=Berman-Kowalewski, M. | author2=Gulland, F. | author3=Wilkin, S. | author4=Calambokidis, J. | author5=Mate, B. | author6=Cordaro, J. | author7=Rotstein, D. | author8=St. Leger, J. | author9=Collins, P. | author10=Fahy, K. | author11=Dover, S. | s2cid=86304413 | title=Association between blue whale mortality and ship strikes along the California coast | journal=Aquatic Mammals | volume=36 | issue=1 | pages=59–66 | date=2010| doi=10.1578/AM.36.1.2010.59 }}</ref> A total of 17 blue whales were killed or suspected to have been killed by ships between 1998 and 2019 off the U.S. West Coast.<ref name="NOAA" /> Five deaths in 2007 off California were considered an unusual mortality event, as defined under the ].<ref name=Berman-Kowalewski_etal_2010/><ref name=Abramson_etal_2009>{{cite report | author1=Abramson, L. | author2=Polefka, S. | author3=Hastings, S. | author4=Bor, K. | title=Reducing the Threat of Ship Strikes on Large Cetaceans in the Santa Barbara Channel Region and Channel Islands National Marine Sanctuary: Recommendations and Case Studies | publisher=Channel Islands National Marine Sanctuary Advisory Council | pages=1–73 | date=2009}}</ref> Lethal ship strikes are also a problem in Sri Lankan waters, where their habitat intersects with one of the world's most active shipping routes.<ref name=deVos_etal_2016>{{cite journal | author1=de Vos, A. | author2=Brownell, R. L. Jr. | author3=Tershy, B. R. | author4=Croll, D. A. | title=Anthropogenic threats and conservation needs of blue whales, "Balaenoptera musculus indica", around Sri Lanka | journal=J. Mar. Biol. | volume=2016 | issue=8420846 | pages=1–12 | date=2016| doi=10.1155/2016/8420846 | doi-access=free }}</ref> Here, strikes caused the deaths of eleven blue whales in 2010 and 2012,<ref name=Priyadarshana_etal_2015>{{cite report | author1=Priyadarshana, T. | author2=Randage, R. | author3=Alling, A. | author4=Calderan, S. | author5=Gordon, J. | author6=Leaper, R. | author7=Porter, L. | title=An update on work related to ship strike risk to Blue whales off southern Sri Lanka | publisher=The International Whaling Commission | volume=SC66A | date=2015}}</ref> and at least two in 2014.<ref name=Randage_etal_2014>{{cite journal | author1=Randage, S. M. | author2=Alling, A. | author3=Currier, K. | author4=Heywood, E. | title=Review of the Sri Lanka blue whale (''Balaenoptera musculus'') with observations on its distribution in the shipping lane | journal=Journal of Cetacean Research and Management | year=2023 | volume=14 | pages=43–49 | doi=10.47536/jcrm.v14i1.522 | s2cid=46399716 | doi-access=free }}</ref> Ship-strike mortality claimed the lives of two blue whales off southern Chile in the 2010s.<ref name=Brownell_etal_2014>{{cite report | author1=Brownell, R. L. Jr. | author2=Cabrera, E. | author3=Galletti-Vernazzani, B. | title=Dead blue whale in Puerto Montt, Chile: Another case of ship collision mortality | publisher=International Whaling Commission | volume=SC/65b/HIM08 | date=2014}}</ref><ref name=IWC_2017>{{cite report | author1=International whaling Commission | title=Report of the Scientific Committee | publisher=International Whaling Commission | page=136 | date=2017}}</ref> Possible measures for reducing future ship strikes include better predictive models of whale distribution, changes in shipping lanes, vessel speed reductions, and seasonal and dynamic management of shipping lanes.<ref name=Redfern_etal_2013>{{cite journal | author1=Redfern, J. V. | author2=McKenna, M. F. | author3=Moore, T. J. | author4=Calambokidis, J. | author5=Deangelis, M. L. | author6=Becker, E. A. | author7=Barlow, J. | author8=Forney, K. A. | author9=Fiedler, P. C. | author10=Chivers, S. J. | title=Assessing the risk of ships striking large whales in marine spatial planning | journal=] | volume=22 | issue=2 | pages=292–302 | date=2013| doi=10.1111/cobi.12029 | pmid=23521668 | bibcode=2013ConBi..27..292R | s2cid=17833403 }}</ref><ref name=Dransfield_etal_2014>{{cite journal | author1=Dransfield, A. | author2=Hines, E. | author3=McGowan, J. | author4=Holzman, B. | author5=Nur, N. | author6=Elliott, M. | author7=Howar, J. | author8=Jacncke, J. | title=Where the whales are: using habitat modeling to support changes in shipping regulations within National Marine Sanctuaries in Central California | journal=Endanger Species Res | volume=26 | issue=1 | pages=39–57 | date=2014| doi=10.3354/esr00627 | doi-access=free }}</ref> Few cases of blue whale entanglement in commercial fishing gear have been documented. The first report in the U.S. occurred off California in 2015, reportedly some type of deep-water trap/pot fishery.<ref name=Carretta_etal_2017>{{cite report | author1=Carretta, J. V. | author2=Muto, M. M. | author3=Greenman, J. | author4=Wilkinson, K. | author5=Viezbicke, J. | author6=Jannot, J. | title=Sources of human-related injury and mortality for U.S. Pacific west coast marine mammal stock assessments, 2011– 2015 | publisher=NOAA | volume=PSRG-2017-07 | date=2017}}</ref> Three more entanglement cases were reported in 2016.<ref name=NMFS_2017>{{cite report | author1=NMFS | title=National Report on Large Whale Entanglements | publisher=NOAA | url=https://www.fisheries.noaa.gov/resource/document/national-report-large-whale-entanglements-2017 | date=2017}}</ref> In Sri Lanka, a blue whale was documented with a net wrapped through its mouth, along the sides of its body, and wound around its tail.<ref name=deVos_2015>{{cite book | author1=de Vos, A. | title=Deepwater Horizon oil spill: Final Programmatic Damage Assessment and Restoration Plan and Final Programmatic Environmental Impact Statement | chapter=Marine life on the line | editor1-last=Braun | editor1-first=D. | publisher=National Geographic | page=685 | chapter-url=http://www.gulfspillrestoration.noaa.gov/restoration-planning/gulf-plan | date=2015}}</ref>


Increasing ] underwater noise impacts blue whales.<ref name=Southall_etal_2018>{{cite journal | author1=Southall, B. L. | author2=Hatch, L. | author3=Scholik-Schlomer, A. | author4=Bergmann, T. | author5=Jasny, M. | author6=Metcalf, K. | author7=Weilgart, L. | author8=Wright, A. J. | author9=Perera, M. E. | title=Reducing noise from large commercial ships: progress and partnerships | journal=Proc. Mar. Saf. Sec. Council | volume=1 | pages=58–65 | date=2018}}</ref><ref name=Wiggins_etal_2001>{{cite journal | author1=Wiggins, S. M. | author2=Oleson, E. M. | author3=Hildebrand, J. A. | title=Blue whale call intensity varies with ambient noise level | journal=] | volume=110 | issue=5 | page=2771 | date=2001| bibcode=2001ASAJ..110.2771W | doi=10.1121/1.4777708 }}</ref> They may be exposed to noise from commercial shipping<ref name=McKenna_etal_2012>{{cite journal | author1=McKenna, M. F. | author2=Ross, D. | author3=Wiggins, S. M. | author4=Hildebrand, J. A. | s2cid=9474116 | title=Underwater radiated noise from modern commercial ships | journal=The Journal of the Acoustical Society of America | volume=131 | issue=1 | pages=92–103 | date=2012| doi=10.1121/1.3664100 | pmid=22280574 | bibcode=2012ASAJ..131...92M }}</ref><ref name=Szesciorka_etal_2019>{{cite journal | author1=Szesciorka, A. R. | author2=Allen, A. N. | author3=Calambokidis, J. | author4=Fahlbusch, J. | author5=McKenna, M. F. | author6=Southall, B. L. | title=A case study of a near vessel strike of a blue whale: perceptual cues and fine-scale aspects of behavioral avoidance | journal=Front. Mar. Sci. | volume=6 | issue=761 | pages=1–10 | date=2019| doi=10.3389/fmars.2019.00761 | doi-access=free }}</ref> and seismic surveys as a part of oil and gas exploration.<ref name=DiIorio_Ckark_2009>{{cite journal | author1=Di Iorio, L. | author2=Clark, C. W. | title=Exposure to seismic survey alters blue whale acoustic communication | journal=Biology Letters | volume=6 | issue=1 | pages=1–4 | date=2009}}</ref><ref name=McDonald_etal_1995>{{cite journal | author1=McDonald, M. A. | author2=Hildebrand, J. A. | author3=Webb, S. C. | s2cid=3829165 | title=Blue and fin whales observed on a seafloor array in the Northeast Pacific | journal=Journal of the Acoustical Society of America | volume=98 | issue=2 | pages=712–721 | date=1995| doi=10.1121/1.413565 | pmid=7642810 | bibcode=1995ASAJ...98..712M | url=https://escholarship.org/uc/item/2sx2b1cj }}</ref> Blue whales in the ] decreased calling in the presence of mid-frequency active (MFA) ].<ref name="Melcón_etal_2012">{{cite journal | author1=Melcón, M. L. | author2=Cummins, A. J. | author3=Kerosky, S. M. | author4=Roche, L. K. | author5=Wiggins, S. M. | author6=Hildebrand, J. A. | title=Blue Whales Respond to Anthropogenic Noise | journal=PLOS ONE | volume=7 | issue=2 | page=e32681 | date=2012| doi=10.1371/journal.pone.0032681 | pmid=22393434 | pmc=3290562 | bibcode=2012PLoSO...732681M | doi-access=free }}</ref> Exposure to simulated MFA sonar was found to interrupt blue whale deep-dive feeding but no changes in behavior were observed in individuals feeding at shallower depths. The responses also depended on the animal's behavioral state, its (horizontal) distance from the sound source and the availability of prey.<ref name=Southall_etal_2019>{{cite journal | author1=Southall, B. L. | author2=DeRuiter, S. L. | author3=Friedlaender, A. | author4=Stimpert, A. K. | author5=Goldbogen, J. A. | author6=Hazen, E. | author7=Casey, C. | author8=Fregosi, S. | author9=Cade, D. E. | author10=Allen, A. N. | author11=Harris, C. M. | author12=Schorr, G. | author13=Moretti, D. | title=Behavioral responses of individual blue whales (''Balaenoptera musculus'') to mid-frequency military sonar | journal=]| volume=222 | issue=jeb190637 | pages=jeb190637 | date=2019| doi=10.1242/jeb.190637 | pmid=30833464 | doi-access=free | bibcode=2019JExpB.222B0637S | hdl=10023/19592 | hdl-access=free }}</ref>
The ] counts the blue whale as "endangered" as it has since the list's inception. In the ], the ] lists them as endangered under the ].<ref>{{cite web
|url=http://www.nmfs.noaa.gov/pr/laws/esa/
|title=Endangered Species Act
}}</ref> The largest known concentration, consisting of about 2,000 individuals, is the North-East Pacific population of the Northern blue whale (''B. m. musculus'') subspecies that ranges from ] to ] but is most commonly seen from California in summer. Infrequently, this population visits the North-West Pacific between ] and the northern tip of Japan.


The potential impacts of ] on blue whales is unknown. However, because blue whales feed low on the ], there is a lesser chance for ] of organic chemical contaminants.<ref name=OShea_Brownell_1994>{{cite journal | author1=O'Shea, T. J. | author2=Brownell, R. L. | title=Organochlorine and metal contaminants in baleen whales:a review and evaluation of conservation implications | journal=]| volume=154 | issue=2–3 | pages=179–200 | date=1994| doi=10.1016/0048-9697(94)90087-6 | pmid=7973606 | bibcode=1994ScTEn.154..179O }}</ref> Analysis of the earwax of a male blue whale killed by a collision with a ship off the coast of California showed contaminants like pesticides, flame retardants, and mercury. Reconstructed ] (POP) profiles suggested that a substantial ] occurred during gestation and/or lactation.<ref name=Trumble_etal_2013>{{cite journal | author1=Trumble, S. J. | author2=Robinson, E. M. | author3=Berman-Kowalewski, M. | author4=Potter, C. W. | author5=Usenko, S. | title=Blue whale earplug reveals lifetime contaminant exposure and hormone profiles | journal=Proceedings of the National Academy of Sciences | volume=110 | issue=42 | pages=16922–16926 | date=2013| doi=10.1073/pnas.1311418110 | bibcode=2013PNAS..11016922T | doi-access=free | pmid=24043814 | pmc=3801066 }}</ref> Male blue whales in the ], Canada, were found to have higher concentrations of PCBs, ] (DDT), ], and several other organochlorine compounds relative to females, reflecting maternal transfer of these persistent contaminants from females into young.<ref name=Metcalfe_etal_2004>{{cite journal | author1=Metcalfe, C. D. | author2=Koenig, B. G. | author3=Metcalfe, T. L. | author4=Paterson, G. | author5=Sears, R. | title=Intra- and inter-species differences in persistent organic contaminants in the blubber of blue whales and humpback whales from the Gulf of St. Lawrence, Canada | journal=Marine Environmental Research| volume=57 | issue=4 | pages=245–260 | date=2004| doi=10.1016/j.marenvres.2003.08.003 | pmid=14749058 | bibcode=2004MarER..57..245M }}</ref>
In the North Atlantic, two stocks of ''B. m. musculus'' are recognized. The first is found off ], ], ] and the ]. This group is estimated to total about 500. The second, more easterly group is spotted from the ] in spring to Iceland in July and August; it is presumed that the whales follow the ] between the two volcanic islands. Beyond Iceland, blue whales have been spotted as far north as ] and ], though such sightings are rare. Scientists do not know where these whales spend their winters. The total North Atlantic population is estimated to be between 600 and 1,500.


== See also ==
In the Southern Hemisphere, there appear to be two distinct subspecies, ''B. m. intermedia'', the Antarctic blue whale, and the little-studied pygmy blue whale, ''B. m. brevicauda'', found in Indian Ocean waters. The most recent surveys (midpoint 1998) provided an estimate of 2,280 blue whales in the Antarctic.<ref>{{cite journal
{{Portal|Cetaceans|Mammals|Marine life}}
|last=Branch
* ]
|first=T.A.
* ]
|title=Abundance of Antarctic blue whales south of 60°S from three complete circumpolar sets of surveys
* ]
|journal=Journal of Cetacean Research and Management
* ]
|volume=9
|issue=3
|pages=87–96
|year=2007}}</ref>, of which fewer than 1% are likely to be pygmy blue whales<ref>{{cite journal
|author=T.A. Branch
|title=Separating southern blue whale subspecies based on length frequencies of sexually mature females
|journal=Marine Mammal Science
|volume=23
|issue=4
|pages=803–833
|year=2007
|doi=10.1111/j.1748-7692.2007.00137.x
|last2=Abubaker
|first2=E. M. N.
|last3=Mkango
|first3=S.
|last4=Butterworth
|first4=D. S.}}</ref> Estimates from a 1996 survey were that 424 pygmy blue whales were in a small area south of ] alone,<ref>{{cite journal
| title = The abundance of blue whales on the Madagascar Plateau, December 1996
| author = P.B. Best
| journal = Journal of Cetacean Research and Management
| volume = 5
| pages = 253–260
| year = 2003}}</ref> thus it is likely that numbers in the entire Indian Ocean are in the thousands. If this is true, the global numbers would be much higher than estimates predict.<ref name=BBC_pop/>


==Note==
A fourth subspecies, ''B. m. indica'', was identified by ] in 1859 in the northern Indian Ocean, but difficulties in identifying distinguishing features for this subspecies led to it being used a synonym for ''B. m. brevicauda'', the pygmy blue whale. Records for Soviet catches seem to indicate that the female adult size is closer to that of the Pygmy Blue than ''B. m. musculus'', although the populations of ''B. m. indica'' and ''B. m. brevicauda'' appear to be discrete, and the breeding seasons differ by almost six months.<ref name = SHDistribution>{{cite journal
{{notelist}}
|title=Past and present distribution, densities and movements of blue whales ''Balaenoptera musculus'' in the Southern Hemisphere and northern Indian Ocean
|author=T. A. Branch, K. M. Stafford, D. M. Palacios
|journal = Mammal Review
|year=2007
| volume = 37
| pages = 116–175
|doi=10.1111/j.1365-2907.2007.00106.x}}</ref>


== References ==
Migratory patterns of these subspecies are not well known. For example, pygmy blue whales have been recorded in the northern Indian Ocean (], ], ]), where they may form a distinct resident population.<ref name= SHDistribution /> In addition, the population of blue whales occurring off ] and ] may also be a distinct population. Some Antarctic blue whales approach the eastern South Atlantic coast in winter, and occasionally, their vocalizations are heard off Peru, Western Australia, and in the northern Indian Ocean.<ref name= SHDistribution /> In Chile, the ], with support from the ], is undertaking extensive research and conservation work on a recently discovered feeding aggregation of the species off the coast of ] in an area named "Golfo del Corcovado", where 326 blue whales were spotted in the summer of 2007.<ref>{{cite web
{{Reflist}}
| title=Blue Whales in Chile: The Giants of Marine Conservation
| publisher=The Rufford Small Grants Foundation
| url=http://www.ruffordsmallgrants.org/files/2007%20Rufford%201st%20phase%20blue%20whale%20report%20Chile_CBA.pdf
|author=R. Hucke-Gaete, B. Carstens, A. Ruiz-Tagle y M. Bello
|format=PDF
| accessdate=2009-03-22}}</ref>


== Further reading ==
Efforts to calculate the blue whale population more accurately are supported by marine mammologists at ] who maintain the OBIS-SEAMAP (Ocean Biogeographic Information System—Spatial Ecological Analysis of Megavertebrate Populations), a collation of marine mammal sighting data from around 130 sources.<ref>The data for the blue whale, along with a species profile, may be found here </ref>

===Threats other than hunting===
], near Santa Barbara, CA]]
Due to their enormous size, power and speed, adult blue whales have virtually no natural predators. There is, however, one documented case in '']'' of a blue whale being attacked by ]s; although the Orcas were unable to kill the animal outright during their attack, the blue whale sustained massive wounds and probably died as a result of them shortly after the attack.<ref>{{cite journal
| author = Tarpy, C.
| title = Killer whale attack!
| journal = National Geographic
| year = 1979
| volume = 155
| issue = 4 (April)
| pages = 542–545 }}</ref>

Blue whales may be wounded, sometimes fatally, after colliding with ocean vessels as well as becoming trapped or entangled in fishing gear.<ref name="recplan98"/> The ever-increasing amount of ocean noise, including ], drowns out the vocalizations produced by whales, which may make it harder for them to communicate.<ref name="recplan98"/> Human threats to the potential recovery of blue whale populations also include accumulation of ] (PCB) chemicals within the whale's body.<ref name="wheelock" />

With ] causing glaciers and permafrost to melt rapidly and allowing a large amount of fresh water to flow into the oceans, there are concerns that if the amount of fresh water in the oceans reaches a critical point, there will be a disruption in the ].{{Citation needed|date=April 2010}} Considering the blue whale's migratory patterns are based on ocean temperature, a disruption in this circulation, which moves warm and cold water around the world, would be likely to have an effect on their migration.<ref>{{cite web
|url=http://www.bto.org/research/reports/researchrpt_complete/RR414_Climate%20change_&_migratory_species.pdf
|author=Robert A. Robinson, Jennifer A. Learmonth, Anthony M. Hutson, Colin D. Macleod, Tim H. Sparks, David I. Leech, Graham J. Pierce, Mark M. Rehfisch and Humphrey Q.P. Crick
|title=Climate Change and Migratory Species
|publisher=BTO
|month=August
| year=2005
| accessdate = 2007-07-09
|format=PDF}}</ref> The whales summer in the cool, high latitudes, where they feed in ]-abundant waters; they winter in warmer, low latitudes, where they mate and give birth.<ref>{{cite journal
| author = Hucke-Gaete, Rodrigo, Layla P. Osman, Carlos A. Moreno, Ken P. Findlay, and Don K. Ljungblad
| title = Discovery of a Blue Whale Feeding and Nursing Ground in Southern Chile
| journal = The Royal Society
| year = 2003
| pages = s170-s173
| url = http://www.pubmedcentral.nih.gov.oca.ucsc.edu/picrender.fcgi?artid=1810017&blobtype=pdf}}</ref>

The change in ocean temperature would also affect the blue whale's food supply. The warming trend and decreased salinity levels would cause a significant shift in krill location and abundance.<ref>{{cite journal
| author = Moline, Mark A., Herve Claustre, Thomas K. Frazer, Oscar Schofield, and Maria Vernet
| title = Alteration of the Food Web Along the Antarctic Peninsula in Response to a Regional Warming Trend
| journal = Global Change Biology
| volume = 10
| year = 2004
| pages = 1973–1980
| url = http://www.blackwell-synergy.com.oca.ucsc.edu/doi/abs/10.1111/j.1365-2486.2004.00825.x
| doi = 10.1111/j.1365-2486.2004.00825.x}}</ref>

==Museums==
]]]
The ] in ] contains a famous mounted skeleton and life-size model of a blue whale, which were both the first of their kind in the world but have since been replicated at the ]. Similarly, the ] in ] has a full-size model in its Milstein Family Hall of Ocean Life. A juvenile blue whale skeleton is installed at the ] in ].

The ] in ] features a life-size model of a mother blue whale with her calf suspended from the ceiling of its main hall.<ref>{{cite web
| title=Aquarium of the Pacific - Online Learning Center - Blue Whale
| url=http://www.aquariumofpacific.org/onlinelearningcenter/species/blue_whale/
| accessdate=2009-08-12}}</ref> The ] at ], Canada, is in the final stages of installing a housed display of a blue whale directly on the main campus boulevard.<ref>{{cite web|url=http://www.beatymuseum.ubc.ca/projblue01.html|title=The Blue Whale Project |date=2010|work=Beaty Biodiversity Museum|publisher=University of British Columbia|accessdate=2 May 2010|location= Vancouver, BC}}</ref> A real skeleton of a blue whale at the ] in Ottawa, Canada was also unveiled in May 2010 <ref>http://nature.ca/en/plan-your-visit/what-see-do/our-exhibitions/water-gallery</ref>

The Museum of Natural History in Gothenburg Sweden contains the only stuffed Blue Whale in the world. There you can also find the skeleton of the whale mounted beside the whale.

== Whale-watching ==
Living blue whales may be encountered on ] cruises in the ]<ref>{{cite journal
|author= Wenzel FW, Mattila DK, Clapham PJ
|year=1988
|title=''Balaenoptera musculus'' in the Gulf of Maine
|journal= Mar. Mammal Sci.
|volume=4
|pages= 172–175
|doi=10.1111/j.1748-7692.1988.tb00198.x}}</ref> and are the main attractions along the north shore of the ] and in the Saint Lawrence estuary.<ref name="recplan98">{{Cite book
| author = Reeves RR, Clapham PJ, Brownell RL, Silber GK
| title =Recovery plan for the blue whale ''(Balaenoptera musculus)''
| year = 1998
| page = 42
| place = Silver Spring, MD
| publisher = National Marine Fisheries Service
| accessdate=2007-06-20
| url=http://www.nmfs.noaa.gov/pr/pdfs/recovery/whale_blue.pdf
|format=PDF}}</ref>

{{Clear}}
==Footnotes==
{{Reflist|colwidth=30em}}

==References==
{{Portal|Cetaceans}}
{{Refbegin}} {{Refbegin}}
* {{cite book
*{{RefAudubonMarineMammals}} pp.&nbsp;89–93.
*{{Cite book
| title = Blue Whales | title = Blue Whales
| author = J. Calambokidis and G. Steiger | author1 = Calambokidis, J.
| author2 = Steiger, G.
| name-list-style = amp
| year = 1998 | year = 1998
| publisher = Voyageur Press | publisher = ]
| isbn = 0-89658-338-4}} | isbn = 978-0-89658-338-2
| url-access = registration
*{{Cite web
| url = https://archive.org/details/bluewhales0000cala
| title=Blue Whale
}}
| work= ]
* {{cite web
| url= http://www.acsonline.org/factpack/bluewhl.htm
| accessdate = 2005-01-07}}
*{{Cite web
| title=Blue whale, ''Balaenoptera musculus'' | title=Blue whale, ''Balaenoptera musculus''
| work = MarineBio.org | work = MarineBio.org
| url = http://marinebio.org/species.asp?id=41 | url = http://marinebio.org/species.asp?id=41
| accessdate = 2006-04-21}} | access-date = 21 April 2006}}
* Blue whale biology & status * Blue whale biology & status
{{Refend}} {{Refend}}


==External links== == External links ==
{{Spoken Misplaced Pages|Blue whale.ogg|date=13 April 2006}}
{{Commons
* – Cornell Lab of Ornithology—Bioacoustics Research Program (archived 26 February 2015)
|Balaenoptera musculus}}
*
{{Wikispecies
*
|Balaenoptera musculus}}
*
{{Spoken Misplaced Pages|Blue whale.ogg|2006-04-13}}
* {{Webarchive|url=https://web.archive.org/web/20191231040638/http://www.bbcamerica.com/shows/the-hunt/video-extras/life-of-a-hunter-blue-whale |date=31 December 2019 }} – BBC America
*
* – BBC America
* ] *<!--- Note the double-linking in the line above is a deliberate to keep the section looking neat -->
* - ] Lab of Ornithology—Bioacoustics Research Program
*
*
*
*
*


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Latest revision as of 01:41, 8 January 2025

Baleen whale, largest animal ever known For other uses, see Blue whale (disambiguation).

Blue whale
Temporal range: Early Pleistocene – Recent 1.5–0 Ma PreꞒ O S D C P T J K Pg N
Adult blue whale
(Balaenoptera musculus)
Size compared to an average human
Conservation status

Endangered  (IUCN 3.1)
CITES Appendix I (CITES)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Infraorder: Cetacea
Family: Balaenopteridae
Genus: Balaenoptera
Species: B. musculus
Binomial name
Balaenoptera musculus
(Linnaeus, 1758)
Subspecies
  • B. m. brevicauda Ichihara, 1966
  • ?B. m. indica Blyth, 1859
  • B. m. intermedia Burmeister, 1871
  • B. m. musculus Linnaeus, 1758
Blue whale range (in blue)
Synonyms
  • Balaena musculus Linnaeus, 1758
  • Balaenoptera gibbar Scoresby 1820
  • Pterobalaena gigas Van Beneden 1861
  • Physalus latirostris Flower 1864
  • Sibbaldius borealis Gray 1866
  • Flowerius gigas Lilljeborg 1867
  • Sibbaldius sulfureus Cope 1869
  • Balaenoptera sibbaldii Sars 1875

The blue whale (Balaenoptera musculus) is a marine mammal and a baleen whale. Reaching a maximum confirmed length of 29.9 m (98 ft) and weighing up to 199 t (196 long tons; 219 short tons), it is the largest animal known ever to have existed. The blue whale's long and slender body can be of various shades of greyish-blue on its upper surface and somewhat lighter underneath. Four subspecies are recognized: B. m. musculus in the North Atlantic and North Pacific, B. m. intermedia in the Southern Ocean, B. m. brevicauda (the pygmy blue whale) in the Indian Ocean and South Pacific Ocean, and B. m. indica in the Northern Indian Ocean. There is a population in the waters off Chile that may constitute a fifth subspecies.

In general, blue whale populations migrate between their summer feeding areas near the poles and their winter breeding grounds near the tropics. There is also evidence of year-round residencies, and partial or age/sex-based migration. Blue whales are filter feeders; their diet consists almost exclusively of krill. They are generally solitary or gather in small groups, and have no well-defined social structure other than mother–calf bonds. Blue whales vocalize, with a fundamental frequency ranging from 8 to 25 Hz; their vocalizations may vary by region, season, behavior, and time of day. Orcas are their only natural predators.

The blue whale was abundant in nearly all the Earth's oceans until the end of the 19th century. It was hunted almost to the point of extinction by whalers until the International Whaling Commission banned all blue whale hunting in 1966. The International Union for Conservation of Nature has listed blue whales as Endangered as of 2018. It continues to face numerous man-made threats such as ship strikes, pollution, ocean noise, and climate change. Scientists found evidence of this through morphological or epidemiological analysis. These analyses are accompanied by chemical profiles that use fecal and tissue which continue to prove the impact of man-made threats.

Taxonomy

See also: Evolution of cetaceans

Nomenclature

The genus name, Balaenoptera, means winged whale, while the species name, musculus, could mean "muscle" or a diminutive form of "mouse", possibly a pun by Carl Linnaeus when he named the species in Systema Naturae. One of the first published descriptions of a blue whale comes from Robert Sibbald's Phalainologia Nova, after Sibbald found a stranded whale in the estuary of the Firth of Forth, Scotland, in 1692. The name "blue whale" was derived from the Norwegian blåhval, coined by Svend Foyn shortly after he had perfected the harpoon gun. The Norwegian scientist G. O. Sars adopted it as the common name in 1874.

Blue whales were referred to as "Sibbald's rorqual", after Robert Sibbald, who first described the species. Whalers sometimes referred to them as "sulphur bottom" whales, as the bellies of some individuals are tinged with yellow. This tinge is due to a coating of huge numbers of diatoms. (Herman Melville briefly refers to "sulphur bottom" whales in his novel Moby-Dick.)

Evolution

Balaenopteridae

Minke whale

B. musculus (blue whale)

B. borealis (sei whale)

Eschrichtius robustus (gray whale)

B. physalus (fin whale)

Megaptera novaeangliae (humpback whale)

A phylogenetic tree of six baleen whale species

Blue whales are rorquals in the family Balaenopteridae. A 2018 analysis estimates that the Balaenopteridae family diverged from other families in between 10.48 and 4.98 million years ago during the late Miocene. The earliest discovered anatomically modern blue whale is a partial skull fossil from southern Italy identified as B. cf. musculus, dating to the Early Pleistocene, roughly 1.5–1.25 million years ago. The Australian pygmy blue whale diverged during the Last Glacial Maximum. Their more recent divergence has resulted in the subspecies having a relatively low genetic diversity, and New Zealand blue whales have an even lower genetic diversity.

Whole genome sequencing suggests that blue whales are most closely related to sei whales with gray whales as a sister group. This study also found significant gene flow between minke whales and the ancestors of the blue and sei whale. Blue whales also displayed high genetic diversity.

Hybridization

Blue whales are known to interbreed with fin whales. The earliest description of a possible hybrid between a blue whale and a fin whale was a 20 m (66 ft) anomalous female whale with the features of both the blue and the fin whales taken in the North Pacific. A whale captured off northwestern Spain in 1984, was found to have been the product of a blue whale mother and a fin whale father.

Two live blue-fin whale hybrids have since been documented in the Gulf of St. Lawrence (Canada), and in the Azores (Portugal). DNA tests done in Iceland on a blue whale killed in July 2018 by the Icelandic whaling company Hvalur hf, found that the whale was the offspring of a male fin whale and female blue whale; however, the results are pending independent testing and verification of the samples. Because the International Whaling Commission classified blue whales as a "Protection Stock", trading their meat is illegal, and the kill is an infraction that must be reported. Blue-fin hybrids have been detected from genetic analysis of whale meat samples taken from Japanese markets. Blue-fin whale hybrids are capable of being fertile. Molecular tests on a 21 m (70 ft) pregnant female whale caught off Iceland in 1986 found that it had a blue whale mother and a fin whale father, while its fetus was sired by a blue whale.

In 2024, a genome analysis of North Atlantic blue whales found evidence that approximately 3.5% of the blue whales' genome was derived from hybridization with fin whales. Gene flow was found to be unidirectional from fin whales to blue whales. Comparison with Antarctic blue whales showed that this hybridization began after the separation of the northern and southern populations. Despite their smaller size, fin whales have similar cruising and sprinting speeds to blue whales, which would allow fin males to complete courtship chases with blue females.

There is a reference to a humpback–blue whale hybrid in the South Pacific, attributed to marine biologist Michael Poole.

Subspecies and stocks

At least four subspecies of blue whale are traditionally recognized, some of which are divided into population stocks or "management units". They have a worldwide distribution, but are mostly absent from the Arctic Ocean and the Mediterranean, Okhotsk, and Bering Sea.

Aerial photograph of an adult blue whale showing its length
Aerial view of adult blue whale
  • Northern subspecies (B. m. musculus)
    • North Atlantic population – This population is mainly documented from New England along eastern Canada to Greenland, particularly in the Gulf of St. Lawrence, during summer though some individuals may remain there all year. They also aggregate near Iceland and have increased their presence in the Norwegian Sea. They are reported to migrate south to the West Indies, the Azores and northwest Africa.
    • Eastern North Pacific population – Whales in this region mostly feed off California's coast from summer to fall and then Oregon, Washington State, the Alaska Gyre and Aleutian Islands later in the fall. During winter and spring, blue whales migrate south to the waters of Mexico, mostly the Gulf of California, and the Costa Rica Dome, where they both feed and breed.
    • Central/Western Pacific population – This stock is documented around the Kamchatka Peninsula during the summer; some individuals may remain there year-round. They have been recorded wintering in Hawaiian waters, though some can be found in the Gulf of Alaska during fall and early winter.
  • Northern Indian Ocean subspecies (B. m. indica) – This subspecies can be found year-round in the northwestern Indian Ocean, though some individuals have recorded travelling to the Crozet Islands during between summer and fall.
  • Pygmy blue whale (B. m. brevicauda)
  • Antarctic subspecies (B. m. intermedia) – This subspecies includes all populations found around the Antarctic. They have been recorded to travel as far north as eastern tropical Pacific, the central Indian Ocean, and the waters of southwestern Australia and northern New Zealand.

Blue whales off the Chilean coast might be a separate subspecies based on their geographic separation, genetics, and unique song types. Chilean blue whales might overlap in the Eastern Tropical Pacific with Antarctica blue whales and Eastern North Pacific blue whales. Chilean blue whales are genetically differentiated from Antarctica blue whales such that interbreeding is unlikely. However, the genetic distinction is less between them and the Eastern North Pacific blue whale, hence there might be gene flow between the Southern and Northern Hemispheres. A 2019 study by Luis Pastene, Jorge Acevedo and Trevor Branch provided new morphometric data from a survey of 60 Chilean blue whales, hoping to address the debate about the possible distinction of this population from others in the Southern Hemisphere. Data from this study, based on whales collected in the 1965/1966 whaling season, shows that both the maximum and mean body length of Chilean blue whales lies between these values in pygmy and Antarctic blue whales. Data also indicates a potential difference in snout-eye measurements between the three, and a significant difference in fluke-anus length between the Chilean population and pygmy blue whales. This further confirms Chilean blue whales as a separate population, and implies that they do not fall under the same subspecies as the pygmy blue whale (B. m. brevicauda).

A 2024 genomic study of the global blue whale population found support for the subspecific status of Antarctic and Indo-western Pacific blue whales but not eastern Pacific blue whales. The study found "...divergence between the eastern North and eastern South Pacific, and among the eastern Indian Ocean, the western South Pacific and the northern Indian Ocean." and "no divergence within the Antarctic".

Description

A blue whale with its bow wave, showing the blowhole

The blue whale is a slender-bodied cetacean with a broad U-shaped head; thin, elongated flippers; a small 33 centimeters (13 in) sickle-shaped dorsal fin located close to the tail, and a large tail stock at the root of the wide and thin flukes. The upper jaw is lined with 70–395 black baleen plates. The throat region has 60–88 grooves which allows the skin to expand during feeding. It has two blowholes that can squirt 9.1–12.2 meters (30–40 ft) up in the air. The skin has a mottled grayish-blue coloration, appearing blue underwater. The mottling patterns near the dorsal fin vary between individuals. The underbelly has lighter pigmentation and can appear yellowish due to diatoms in the water, which historically earned them the nickname "sulphur bottom". The male blue whale has the largest penis in the animal kingdom, at around 3 m (9.8 ft) long and 12 in (30 cm) wide.

Size

Photograph of a blue whale skull
A blue whale skull measuring 5.8 meters (19 ft)

The blue whale is the largest animal known ever to have existed. Some studies have estimated that certain shastasaurid ichthyosaurs and the ancient whale Perucetus could have rivalled the blue whale in size, with Perucetus also being heavier than the blue whale with a mean weight of 180 t (180 long tons; 200 short tons). These estimates are based on fragmentary remains, and the proposed size for the latter has been disputed in 2024. Other studies estimate that on land, large sauropods like Bruhathkayosaurus (mean weight: 110–170 tons) and Maraapunisaurus (mean weight: 80–120 tons) would have easily rivalled the blue whale, with the former even exceeding the blue whale based on its most liberal estimations (240 tons), although these estimates are based on even more fragmentary specimens that had disintegrated by the time those estimates were made.

The International Whaling Commission (IWC) whaling database reports 88 individuals longer than 30 meters (98 ft), including one of 33 meters (108 ft). The Discovery Committee reported lengths up to 31 meters (102 ft). The longest scientifically measured individual blue whale was 30 meters (98 ft) from rostrum tip to tail notch. Female blue whales are larger than males. Hydrodynamic models suggest a blue whale could not exceed 33 metres (108 ft) because of metabolic and energy constraints.

The average length of sexually mature female blue whales is 22.0 meters (72.1 ft) for Eastern North Pacific blue whales, 24 meters (79 ft) for central and western North Pacific blue whales, 21–24 meters (68–78 ft) for North Atlantic blue whales, 25.4–26.3 meters (83.4–86.3 ft) for Antarctic blue whales, 23.5 meters (77.1 ft) for Chilean blue whales, and 21.3 meters (69.9 ft) for pygmy blue whales.

In the Northern Hemisphere, males weigh an average 100 metric tons (220,000 lb) and females 112 metric tons (247,000 lb). Eastern North Pacific blue whale males average 88.5 tonnes (195,000 lb) and females 100 tonnes (220,000 lb). Antarctic males average 112 tonnes (247,000 lb) and females 130 tonnes (290,000 lb). Pygmy blue whale males average 83.5 tonnes (184,000 lb) to 99 tonnes (218,000 lb). The weight of the heart of a stranded North Atlantic blue whale was 180 kg (400 lb), the largest known in any animal. The record-holder blue whale was recorded at 173 tonnes (190 short tons), with estimates of up to 199 tonnes (220 short tons).

In 2024, Motani and Pyenson calculated the body mass of blue whales at different lengths, compiling records of their sizes from previous academic literatures and using regression analyses and volumetric analyses. A 25 metres (82 ft) long individual was estimated to weigh approximately 101–119 tonnes (111–131 short tons), while a 30 metres (98 ft) long individual was estimated to weigh approximately 184–205 tonnes (203–226 short tons). Considering that the largest blue whale was indeed 33 metres (108 ft) long, they estimated that a blue whale of such length would have weighed approximately 252–273 tonnes (278–301 short tons).

During the harvest of a female blue whale, Messrs. Irvin and Johnson collected a fetus that is now 70% preserved and used for educational purposes. The fetus was collected in 1922, so some shrinkage may have occurred, making visualization of some features fairly difficult. However, due to this collection researchers now know that the external anatomy of a blue whale fetus is approximately 133 mm. Along with during the developmental phases, the fetus is located where the embryonic and fetal phases converge. This fetus is the youngest gestational age of the specimen recorded.

Life span

Blue whales live around 80–90 years or more. Scientists look at a blue whale's earwax or ear plug to estimate its age. Each year, a light and dark layer of wax is laid corresponding with fasting during migration and feeding time. Each set is thus an indicator of age. The oldest blue whale found was determined, using this method, to be 110 years old. The maximum age of a pygmy blue whale determined this way is 73 years. In addition, female blue whales develop scars or corpora albicantia on their ovaries every time they ovulate. In a female pygmy blue whale, one corpus albicans is formed on average every 2.6 years.

Behaviour and ecology

Photograph of a whale blowing
The blow of a blue whale

The blue whale is usually solitary, but can be found in pairs. When productivity is high enough, blue whales can be seen in gatherings of more than 50 individuals. Populations may go on long migrations, traveling to their summer feeding grounds towards the poles and then heading to their winter breeding grounds in more equatorial waters. The animals appear to use memory to locate the best feeding areas. There is evidence of alternative strategies, such as year-round residency, and partial (where only some individuals migrate) or age/sex-based migration. Some whales have been recorded feeding in breeding grounds. The traveling speed for blue whales ranges 5–30 kilometers per hour (3.1–18.6 mph). Their massive size limits their ability to breach.

The greatest dive depth reported from tagged blue whales was 315 meters (1,033 ft). Their theoretical aerobic dive limit was estimated at 31.2 minutes, however, the longest dive measured was 15.2 minutes. The deepest confirmed dive from a pygmy blue whale was 506 meters (1,660 ft). A blue whale's heart rate can drop to 2 beats per minute (bpm) at deep depths, but upon surfacing, can rise to 37 bpm, which is close to its peak heart rate.

Diet and feeding

Photograph of the blue whale's small dorsal fin
The small dorsal fin of this blue whale is just visible on the far left.

The blue whale's diet consists almost exclusively of krill. Blue whales capture krill through lunge feeding; they swim towards them at high speeds as they open their mouths up to 80°. They may engulf 220 metric tons (220 long tons; 240 short tons) of water at one time. They squeeze the water out through their baleen plates with pressure from the throat pouch and tongue, and swallow the remaining krill. Blue whales have been recorded making 180° rolls during lunge-feeding, possibly allowing them to search the prey field and find the densest patches.

While pursuing krill patches, blue whales maximize their calorie intake by increasing the number of lunges while selecting the thickest patches. This provides them enough energy for everyday activities while storing additional energy necessary for migration and reproduction. Due to their size, blue whales have larger energetic demands than most animals resulting in their need for this specific feeding habit. Blue whales have to engulf densities greater than 100 krill/m to maintain the cost of lunge feeding. They can consume 34,776–1,912,680 kilojoules (8,312–457,141 kcal) from one mouthful of krill, which can provide up to 240 times more energy than used in a single lunge. It is estimated that an average-sized blue whale must consume 1,120 ± 359 kilograms (2,469 ± 791 lb) of krill a day.

In the southern ocean, blue whales feed on Antarctic krill (Euphausia superba). In the South Australia, pygmy blue whales (B. m. brevicauda) feeds on Nyctiphanes australis. In California, they feed mostly on Thysanoessa spinifera, but also less commonly on North pacific krill (Euphausia pacifica). Research of the Eastern North Pacific population shows that when diving to feed on krill, the whales reach an average depth of 201 meters, with dives lasting 9.8 minutes on average.

While most blue whales feed almost exclusively on krill, the Northern Indian Ocean subspecies (B. m. indica) instead feeds predominantly on sergestid shrimp. To do so, they dive deeper and for longer periods of time than blue whales in other regions of the world, with dives of 10.7 minutes on average, and a hypothesized dive depth of about 300 meters. Fecal analysis also found the presence of fish, krill, amphipods, cephalopods, and scyphozoan jellyfish in their diet.

Blue whales appear to avoid directly competing with other baleen whales. Different whale species select different feeding spaces and times as well as different prey species. In the Southern Ocean, baleen whales appear to feed on Antarctic krill of different sizes, which may lessen competition between them.

Blue whale feeding habits may differ due to situational disturbances, like environmental shifts or human interference. This can cause a change in diet due to stress response. Due to these changing situations, there was a study performed on Blue whales measuring Cortisol levels and comparing them with the levels of stressed individuals, it gave a closer look to the reasoning behind their diet and behavioral changes.

Reproduction and birth

Photograph of a blue whale calf and its mother
A blue whale calf with its mother

Blue whales generally reach sexual maturity at 8–10 years. In the Northern Hemisphere, the length at which they reach maturity is 21–23 meters (69–75 ft) for females and 20–21 meters (66–69 ft) for males. In the Southern Hemisphere, the length of maturity is 23–24 meters (75–79 ft) and 22 meters (72 ft) for females and males respectively. Male pygmy blue whales average 18.7 meters (61.4 ft) at sexual maturity. Female pygmy blue whales are 21.0–21.7 meters (68.9–71.2 ft) in length and roughly 10 years old at the age of sexual maturity. Little is known about mating behavior, or breeding and birthing areas. Blue whales appear to be polygynous, with males competing for females. A male blue whale typically trails a female and will fight off potential rivals. The species mates from fall to winter.

Pregnant females eat roughly four percent of their body weight daily, amounting to 60% of their overall body weight throughout summer foraging periods. Gestation may last 10–12 months with calves being 6–7 meters (20–23 ft) long and weighing 2–3 metric tons (2.0–3.0 long tons; 2.2–3.3 short tons) at birth. Estimates suggest that because calves require 2–4 kilograms (4.4–8.8 lb) milk per kg of mass gain, blue whales likely produce 220 kilograms (490 lb) of milk per day (ranging from 110 to 320 kilograms (240 to 710 lb) of milk per day). The first video of a calf thought to be nursing was filmed in New Zealand in 2016. Calves may be weaned when they reach 6–8 months old at a length of 16 meters (53 ft). They gain roughly 37,500 pounds (17,000 kg) during the weaning period. Interbirth periods last two to three years; they average 2.6 years in pygmy blue whales.

Vocalizations

A blue whale song Recorded in the Atlantic (1)
A blue whale song Recorded in the Atlantic (2)
A blue whale song Recorded in North Eastern Pacific
A blue whale song Recorded in the South Pacific
A blue whale song Recorded in the West Pacific
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Blue whales produce some of the loudest and lowest frequency vocalizations in the animal kingdom, and their inner ears appear well adapted for detecting low-frequency sounds. The fundamental frequency for blue whale vocalizations ranges from 8 to 25 Hz. Blue whale songs vary between populations.

Vocalizations produced by the Eastern North Pacific population have been well studied. This population produces pulsed calls ("A") and tonal calls ("B"), upswept tones that precede type B calls ("C") and separate downswept tones ("D"). A and B calls are often produced in repeated co-occurring sequences and sung only by males, suggesting a reproductive function. D calls may have multiple functions. They are produced by both sexes during social interactions while feeding. and by males when competing for mates.

Blue whale calls recorded off Sri Lanka have a three-unit phrase. The first unit is a 19.8 to 43.5 Hz pulsive call, and is normally 17.9 ± 5.2 seconds long. The second unit is a 55.9 to 72.4 Hz FM upsweep that is 13.8 ± 1.1 seconds long. The final unit is 28.5 ± 1.6 seconds long with a tone of 108 to 104.7 Hz. A blue whale call recorded off Madagascar, a two-unit phrase, consists of 5–7 pulses with a center frequency of 35.1 ± 0.7 Hz lasting 4.4 ± 0.5 seconds proceeding a 35 ± 0 Hz tone that is 10.9 ± 1.1 seconds long. In the Southern Ocean, blue whales produce 18-second vocals which start with a 9-second-long, 27 Hz tone, and then a 1-second downsweep to 19 Hz, followed by a downsweep further to 18 Hz. Other vocalizations include 1–4 second long, frequency-modulated calls with a frequency of 80 and 38 Hz.

There is evidence that some blue whale songs have temporally declined in tonal frequency. The vocalization of blue whales in the Eastern North Pacific decreased in tonal frequency by 31% from the early 1960s to the early 21st century. The frequency of pygmy blue whales in the Antarctic has decreased by a few tenths of a hertz every year starting in 2002. It is possible that as blue whale populations recover from whaling, there is increasing sexual selection pressure (i.e., a lower frequency indicates a larger body size).

Predators and parasites

The only known natural predator to blue whales is the orca, although the rate of fatal attacks by orcas is unknown. Photograph-identification studies of blue whales have estimated that a high proportion of the individuals in the Gulf of California have rake-like scars, indicative of encounters with orcas. Off southeastern Australia, 3.7% of blue whales photographed had rake marks and 42.1% of photographed pygmy blue whales off Western Australia had rake marks. Documented predation by orcas has been rare. A blue whale mother and calf were first observed being chased at high speeds by orcas off southeastern Australia. The first documented attack occurred in 1977 off southwestern Baja California, Mexico, but the injured whale escaped after five hours. Four more blue whales were documented as being chased by a group of orcas between 1982 and 2003. The first documented predation event by orcas occurred in September 2003, when a group of orcas in the Eastern Tropical Pacific was encountered feeding on a recently killed blue whale calf. In March 2014, a commercial whale watch boat operator recorded an incident involving a group of orcas harassing a blue whale in Monterey Bay. The blue whale defended itself by slapping its tail. A similar incident was recorded by a drone in Monterey Bay in May 2017. The first direct observations of orca predation occurred off the south coast of Western Australia, two in 2019 and one more in 2021. The first victim was estimated to be 18–22 meters (59–72 ft).

In Antarctic waters, blue whales accumulate diatoms of the species Cocconeis ceticola and the genera Navicola, which are normally removed when the whales enter warmer waters. Other external parasites include barnacles such as Coronula diadema, Coronula reginae, and Cryptolepas rhachianecti, which latch on their skin deep enough to leave behind a pit if removed. Whale lice species make their home in cracks of the skin and are relatively harmless. The copepod species Pennella balaenopterae digs in and attaches itself to the blubber to feed on. Intestinal parasites include the trematode genera Ogmogaster and Lecithodesmus; the tapeworm genera Priapocephalus, Phyllobotrium, Tetrabothrius, Diphyllobotrium, and Diplogonoporus; and the thorny-headed worm genus Bolbosoma. In the North Atlantic, blue whales also contain the protozoans Entamoeba, Giardia and Balantidium.

Conservation

The global blue whale population is estimated to be 5,000–15,000 mature individuals and 10,000–25,000 total as of 2018. By comparison, there were at least 140,000 mature whales in 1926. There are an estimated total of 1,000–3,000 whales in the North Atlantic, 3,000–5,000 in the North Pacific, and 5,000–8,000 in the Antarctic. There are possibly 1,000–3,000 whales in the eastern South Pacific while the pygmy blue whale may number 2,000–5,000 individuals. Blue whales have been protected in areas of the Southern Hemisphere since 1939. In 1955, they were given complete protection in the North Atlantic under the International Convention for the Regulation of Whaling; this protection was extended to the Antarctic in 1965 and the North Pacific in 1966. The protected status of North Atlantic blue whales was not recognized by Iceland until 1960. In the United States, the species is protected under the Endangered Species Act.

Blue whales are formally classified as endangered under both the U.S. Endangered Species Act and the IUCN Red List. They are also listed on Appendix I under the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) and the Convention on the Conservation of Migratory Species of Wild Animals. Although, for some populations, there is not enough information on current abundance trends (e.g., pygmy blue whales), others are critically endangered (e.g., Antarctic blue whales).

Threats

Dead blue whale on flensing platform

Blue whales were initially difficult to hunt because of their size and speed. This began to change in the mid-19th century with the development of harpoons that can be shot as projectiles. Blue whale whaling peaked between 1930 and 1931 with 30,000 animals taken. Harvesting of the species was particularly high in the Antarctic, with 350,000–360,000 whales taken in the first half of the 20th century. In addition, 11,000 North Atlantic whales (mostly around Iceland) and 9,500 North Pacific whales were killed during the same period. The International Whaling Commission banned all hunting of blue whales in 1966 and gave them worldwide protection. However, the Soviet Union continued to illegally hunt blue whales and other species up until the 1970s.

Researchers examine a dead blue whale killed by collision with a ship

Ship strikes are a significant mortality factor for blue whales, especially off the U.S. West Coast. A total of 17 blue whales were killed or suspected to have been killed by ships between 1998 and 2019 off the U.S. West Coast. Five deaths in 2007 off California were considered an unusual mortality event, as defined under the Marine Mammal Protection Act. Lethal ship strikes are also a problem in Sri Lankan waters, where their habitat intersects with one of the world's most active shipping routes. Here, strikes caused the deaths of eleven blue whales in 2010 and 2012, and at least two in 2014. Ship-strike mortality claimed the lives of two blue whales off southern Chile in the 2010s. Possible measures for reducing future ship strikes include better predictive models of whale distribution, changes in shipping lanes, vessel speed reductions, and seasonal and dynamic management of shipping lanes. Few cases of blue whale entanglement in commercial fishing gear have been documented. The first report in the U.S. occurred off California in 2015, reportedly some type of deep-water trap/pot fishery. Three more entanglement cases were reported in 2016. In Sri Lanka, a blue whale was documented with a net wrapped through its mouth, along the sides of its body, and wound around its tail.

Increasing man-made underwater noise impacts blue whales. They may be exposed to noise from commercial shipping and seismic surveys as a part of oil and gas exploration. Blue whales in the Southern California Bight decreased calling in the presence of mid-frequency active (MFA) sonar. Exposure to simulated MFA sonar was found to interrupt blue whale deep-dive feeding but no changes in behavior were observed in individuals feeding at shallower depths. The responses also depended on the animal's behavioral state, its (horizontal) distance from the sound source and the availability of prey.

The potential impacts of pollutants on blue whales is unknown. However, because blue whales feed low on the food chain, there is a lesser chance for bioaccumulation of organic chemical contaminants. Analysis of the earwax of a male blue whale killed by a collision with a ship off the coast of California showed contaminants like pesticides, flame retardants, and mercury. Reconstructed persistent organic pollutant (POP) profiles suggested that a substantial maternal transfer occurred during gestation and/or lactation. Male blue whales in the Gulf of St. Lawrence, Canada, were found to have higher concentrations of PCBs, dichlorodiphenyltrichloroethane (DDT), metabolites, and several other organochlorine compounds relative to females, reflecting maternal transfer of these persistent contaminants from females into young.

See also

Note

  1. The extinct whale species Perucetus colossus (described in 2023) has been suggested as a potential contender of the blue whale in size, however, this was later disputed in 2024. Several extinct dinosaurs may also have reached a similar mass to the blue whale.

References

  1. ^ Cooke, J.G. (2019) . "Balaenoptera musculus". IUCN Red List of Threatened Species. 2018: e.T2477A156923585. doi:10.2305/IUCN.UK.2018-2.RLTS.T2477A156923585.en. Retrieved 13 June 2024.
  2. "Appendices | CITES". cites.org. Retrieved 14 January 2022.
  3. ^ Bianucci, G.; Lambert, O.; Urbina, M.; Merella, M.; Collareta, A.; Bennion, R.; Salas-Gismondi, R.; Benites-Palomino, A.; Post, K.; de Muizon, C.; Bosio, G.; Di Celma, C.; Malinverno, E.; Pierantoni, P.P.; Villa, I.M.; Amson, E. (2023). "A heavyweight early whale pushes the boundaries of vertebrate morphology". Nature. 620 (7975): 824–829. Bibcode:2023Natur.620..824B. doi:10.1038/s41586-023-06381-1. PMID 37532931. S2CID 260433513.
  4. ^ Motani, R.; Pyenson, N. D. (2024). "Downsizing a heavyweight: factors and methods that revise weight estimates of the giant fossil whale Perucetus colossus". PeerJ. 12. e16978. doi:10.7717/peerj.16978. PMC 10909350. PMID 38436015.
  5. ^ Paul, Gregory S.; Larramendi, Asier (11 April 2023). "Body mass estimate of Bruhathkayosaurus and other fragmentary sauropod remains suggest the largest land animals were about as big as the greatest whales". Lethaia. 56 (2): 1–11. Bibcode:2023Letha..56..2.5P. doi:10.18261/let.56.2.5. ISSN 0024-1164. S2CID 259782734.
  6. ^ Reeves, R. R.; Stewart, P. J.; Clapham, J.; Powell, J. A. (2002). Whales, dolphins, and porpoises of the eastern North Pacific and adjacent Arctic waters: A guide to their identification. New York: Knopf. pp. 234–237.
  7. ^ Calambokidis, J.; Steiger, G. H. (1997). Blue Whales. McGregor, MN: Voyager Press. p. 72.
  8. Linnaeus, Carl (1758). Systema Naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Stockholm, Holmia: Laurentius Salvius. p. 824.
  9. ^ Sibbald, Robert (1692). "Phalainologia Nova". Blue Whale ("Balaenoptera Musculus"): 675–678.
  10. Bortolotti, D. (2008). Wild Blue: A Natural History of the World's Largest Animal. New York: St. Martin's Press.
  11. ^ Bennett, A G (1920). "On the occurrence of diatoms on the skin of whales". Proc. R. Soc. Lond. B. 91 (641): 352–357. doi:10.1098/rspb.1920.0021.
  12. ^ Melville, H. (1851). Moby-Dick. New York: Harper & Brothers. p. 398.
  13. ^ Árnason, U.; Lammers, F.; Kumar, V.; Nilsson, M. A.; Janke, A. (2018). "Whole-genome sequencing of the blue whale and other rorquals finds signatures for introgressive gene flow". Science Advances. 4 (4): eaap9873. Bibcode:2018SciA....4.9873A. doi:10.1126/sciadv.aap9873. PMC 5884691. PMID 29632892.
  14. Bianucci, G.; Marx, F. G.; Collareta, A.; Di Stefano, A.; Landini, W.; Morigi, C.; Varola, A. (2019). "Rise of the titans: baleen whales became giants earlier than thought". Biology Letters. 15 (5): 20190175. doi:10.1098/rsbl.2019.0175. PMC 6548731. PMID 31039728.
  15. Attard, C. R. M.; Beheregaray, L. B.; Jenner, K. C. S.; Gill, P. C.; Jenner, M.-N. M.; Morrice, M. G.; Teske, P. R.; Moller, L. M. (2015). "Low genetic diversity in pygmy blue whales is due to climate-induced diversification rather than anthropogenic impacts". Biology Letters. 11 (5): 20141037. doi:10.1098/rsbl.2014.1037. PMC 4455730. PMID 25948571.
  16. Barlow, D. R.; Torres, L. G.; Hodge, K. B.; Steel, D.; Baker, C. S.; Chandler, T. E.; Bott, N.; Constantine, R.; Double, M. C.; Gill, P.; Glasgow, D.; Hamner, R. M.; Lilley, C.; Ogle, M.; Olson, P. A. (2018). "Documentation of a New Zealand blue whale population based on multiple lines of evidence". Endangered Species Research. 36: 27–40. doi:10.3354/esr00891.
  17. Doroshenko, V. N. (1970). "A whale with features of the fin and the blue whale". Izvestia TINRO. 70: 255–257.
  18. Bérubé, M.; Aguilar, A. (1998). "A new hybrid between a blue whale, Balaenoptera Musculus, and a fin whale, "B. Physalus:" frequency and implications of hybridization". Marine Mammal Science. 14 (1): 82–98. Bibcode:1998MMamS..14...82B. doi:10.1111/j.1748-7692.1998.tb00692.x.
  19. Berube, M.; Oosting, T.; Aguilar, A.; Berrow, S.; Hao, W.; Heide-Jørgensen, M. P.; Kovacs, K. M.; Landry, S.; Lydersen, C.; Martin, V.; Øien, N.; Panigada, S.; Prieto, R.; Ramp, C.; Robbins, J. (2017). Are the "Bastards" coming back? Molecular identification of live blue and fin whale hybrids in the North Atlantic ocean. 22nd Biennial Conference on the Biology of Marine Mammals. Halifax, Nova Scotia, Canada.
  20. Kilvert, Nick (20 July 2018). "DNA test shows slaughtered blue whale is a hybrid, Iceland marine institute says". ABC. Retrieved 21 December 2019.
  21. Fishman, Margie (19 July 2018). "Hybrid blue-fin whale is still protected". Animal Welfare Institute. Retrieved 21 December 2019.
  22. Palumbi, S. R.; Cipriano, F. (1998). "Species identification using genetic tools: the value of nuclear and mitochondrial gene sequences in whale conservation". Journal of Heredity. 89 (5): 459–464. doi:10.1093/jhered/89.5.459. PMID 9768497.
  23. Spilliaert, R.; Vikingsson, G.; Arnason, U.; Palsdottir, A.; Sigurjonsson, J.; Arnason, A. (1991). "Species hybridization between a female blue whale (Balaenoptera rnusctllus) and a male fin whale ("B.pbysalus"): Molecular and morphological documentation". Journal of Heredity. 82 (4): 269–274. doi:10.1093/oxfordjournals.jhered.a111085. PMID 1679066.
  24. Jossey, Sushma; Haddrath, O.; Loureiro, L.; Weir, J.; Lim, B.; Miller, J.; Scherer, S.; Goskøyr, A; Lille-Langøy, R; Kovacs, Kit; Lyndersen, C; Routti, H; Engstrom, M (6 January 2024). "Population structure and history of North Atlantic Blue whales (Balaenoptera musculus musculus) inferred from whole genome sequence analysis". Conservation Genetics. Open access (2): 357–371. Bibcode:2024ConG...25..357J. doi:10.1007/s10592-023-01584-5.
  25. Hatch, L. T.; Dopman, E. B.; Harrison, R. G. (2006). "Phylogenetic relationships among the baleen whales based on maternally and paternally inherited characters". Molecular Phylogenetics and Evolution. 41 (1): 12–27. Bibcode:2006MolPE..41...12H. doi:10.1016/j.ympev.2006.05.023. PMID 16843014.
  26. ^ Oliver, Chris W. (November 2020). Recovery Plan for the Blue Whale (Balaenoptera musculus) (Report). National Oceanic and Atmospheric Administration. Retrieved 12 April 2022.
  27. "List of Marine Mammal Species and Subspecies". The Society for Marine Mammalogy. 13 November 2016. Retrieved 30 December 2019.
  28. LeDuc, R. G.; Dizon, A. E.; Goto, M.; Pastene, L. A.; Kato, H.; Nishiwaki, S.; LeDuc, C. A.; Brownell, R. L. (2023). "Patterns of genetic variation in Southern Hemisphere blue whales, and the use of assignment test to detect mixing on the feeding grounds". Journal of Cetacean Research and Management. 9: 73–80. doi:10.47536/jcrm.v9i1.694. S2CID 257136658.
  29. Torres-Florez, J. P.; Olson, P. A.; Bedrinana-Romano, L.; Rosenbaum, H.; Ruiz, J.; Leduc, R.; Huck-Gaete, R. (2015). "First documented migratory destination for eastern South Pacific blue whales". Marine Mammal Science. 31 (4): 1580–1586. Bibcode:2015MMamS..31.1580T. doi:10.1111/mms.12239.
  30. Buchan, S. J.; Rendell, L. E.; Hucke-Gaete, R. (2010). "Preliminary recordings of blue whale (Balaenoptera musculus) vocalizations in the Gulf of Corcovado, northern Patagonia Chile". Marine Mammal Science. 26 (2): 451–459. Bibcode:2010MMamS..26..451B. doi:10.1111/j.1748-7692.2009.00338.x.
  31. LeDuc, R. G.; Archer, E. I.; Lang, A. R.; Martien, K. K.; Hancock-Hanser, B.; Torres-Florez, J. P.; Hucke-Gaete, R.; Rosenbaum, H. R.; Van Waerebeek, K.; Brownell, R. L. Jr.; Taylor, B. L. (2016). "Genetic variation in blue whales in the eastern Pacific: implication for taxonomy and use of common wintering grounds". Molecular Ecology. 26 (3): 740–751. doi:10.1111/mec.13940. PMID 27891694. S2CID 206184206.
  32. Pastene, Luis A.; Acevedo, Jorge; Branch, Trevor A. (2019). "Morphometric analysis of Chilean blue whales and implications for their taxonomy". Marine Mammal Science. 36 (1): 116–135. doi:10.1111/mms.12625. ISSN 0824-0469.
  33. Attard, C. R. M.; Sandoval-Castillo, J; Lang, A. R.; Vernazzani, B. G.; Torres, L. G.; Baldwin, R; Jenner, K. C. S.; Gill, P. C.; Burton, C. L. K.; Barceló, A; Sironi, M; Jenner, M.-N. M.; Morrice, M. G.; Beheregaray, L. B.; Möller, L. M. (2024). "Global conservation genomics of blue whales calls into question subspecies taxonomy and refines knowledge of population structure". Animal Conservation. 27 (5): 626–638. Bibcode:2024AnCon..27..626A. doi:10.1111/acv.12935.
  34. ^ Sears, R.; Perrin, W. F. (2009). "Blue whale (Balaenoptera musculus)". In Perrin, W. F.; Würsig, B.; Thewissen, J. G. M. (eds.). Encyclopedia of marine mammals. San Diego, CA: Academic Press. pp. 120–124.
  35. ^ Leatherwood, S.; Caldwell, D. K.; Winn, H. E. (1976). "Whales, dolphins, and porpoises of the western North Atlantic". NOAA Technical Report NMFS Circular. 396: 176. Archived from the original on 20 July 2020. Retrieved 31 December 2019.
  36. Leatherwood, S.; Reeves, R. R.; Perrin, W. F.; Evans, W. E. (1982). "Whales, dolphins, and porpoises of the eastern North Pacific and adjacent Arctic waters: A guide to their identification". NOAA Technical Report NMFS Circular. 444: 245.
  37. Sears, R.; Williamson, J. M.; Wenzel, F. W.; Bérubé, M.; Gendron, D.; Jones, P. (1990). "Photographic identification of the blue whale (Balaenoptera musculus) in the Gulf of St. Lawrence, Canada". Reports of the International Whaling Commission. 12: 335–342.
  38. Calambokidis, J.; Barlow, J.; Ford, J. K. B.; Chandler, T. E.; Douglas, A. B. (2009). "Insights into the population structure of blue whales in the Eastern North Pacific from recent sightings and photographic identification". Marine Mammal Science. 25 (4): 816–832. Bibcode:2009MMamS..25..816C. doi:10.1111/j.1748-7692.2009.00298.x. S2CID 83527877.
  39. Gendron, D.; De La Cruz, U.; Winn, H. E. (2012). "A new classification method to simplify blue whale photo-identification technique". Journal of Cetacean Research and Management. 13 (1): 79–84.
  40. Scammon, C. M. (1874). The Marine Mammals of the Northwestern Coast of North America. New York: Dover.
  41. "Reproduction". University of Wisconsin. Retrieved 3 October 2012.
  42. Ruud, J. T. (1956). "The blue whale". Scientific American. 195 (6): 46–50. Bibcode:1956SciAm.195f..46R. doi:10.1038/scientificamerican1256-46.
  43. ^ Lockyer, C. (1981). "Growth and energy budgets of large baleen whales from the southern hemisphere". FAO Fisheries Series (5) Mammals in the Seas. 3: 379–487.
  44. ^ Mizroch, S. A.; Rice, D. W.; Breiwick, J. M. (1984). "The blue whale, Balaenoptera musculus". Marine Fisheries Review. 46: 15–19.
  45. De la Salle P, R Lomax D, A Massare J, Gallois R (2018). "A giant Late Triassic ichthyosaur from the UK and a reinterpretation of the Aust Cliff 'dinosaurian' bones". PLOS ONE. 13 (4). doi:10.6084/m9.figshare.5975440.
  46. ^ McClain, C. R.; Balk, M. A.; Benfield, M. C.; Branch, T. A.; Chen, C.; Cosgrove, J.; Dove, A. D. M.; Helm, R. R.; Hochberg, F. G.; Gaskins, L. C.; Lee, F. B.; Marshall, A.; McMurray, S. E.; Schanche, C.; Stone, S. N. (2015). "Sizing ocean giants: patterns of intraspecific size variation in marine megafauna". PeerJ. e715: e715. doi:10.7717/peerj.715. PMC 4304853. PMID 25649000.
  47. Mackintosh, N. A. (1942). "The southern stocks of whalebone whales". Discovery Reports. 22 (3889): 569–570. Bibcode:1944Natur.153..569F. doi:10.1038/153569a0. S2CID 41590649.
  48. Sears, R.; Calambokidis, J. (2002). Update COSEWIC status report on the blue whale (Balaenoptera musculus) in Canada. Ottawa, ON: Committee on the Status of Endangered Wildlife in Canada. p. 32.
  49. Ralls, K. (1976). "Mammals in which females are larger than males". The Quarterly Review of Biology. 51 (2): 245–270. doi:10.1086/409310. PMID 785524. S2CID 25927323.
  50. Potvin, J.; Goldbogen, J.; Chadwick, R. E. (2012). "Metabolic Expenditures of Lunge Feeding Rorquals Across Scale: Implications for the Evolution of Filter Feeding and the Limits to Maximum Body Size". PLOS ONE. 7 (9): e44854. Bibcode:2012PLoSO...744854P. doi:10.1371/journal.pone.0044854. PMC 3443106. PMID 23024769.
  51. ^ Branch, T. A.; Abubaker, E. M. N.; Mkango, S.; Butterworth, D. S. (2007). "Separating southern blue whale subspecies based on length frequencies of sexually mature females". Marine Mammal Science. 23 (4): 803–833. Bibcode:2007MMamS..23..803B. doi:10.1111/j.1748-7692.2007.00137.x.
  52. ^ Gilpatrick, J. W.; Perryman, W. L. (2008). "Geographic variation in external morphology of North Pacific and Southern Hemisphere blue whales (Balaenoptera musculus)". Journal of Cetacean Research and Management. 10 (1): 9–21. doi:10.47536/jcrm.v10i1.654. S2CID 256926335.
  53. Lockyer, C. (1976). "Body weights of some species of large whales". J. Cons. Int. Explor. Mer. 36 (3): 259–273. doi:10.1093/icesjms/36.3.259.
  54. "See the world's biggest heart". Archived from the original on 16 September 2020. Retrieved 21 August 2015.
  55. "Assessment and Update Status Report on the Blue Whale Balaenoptera musculus" (PDF). Committee on the Status of Endangered Wildlife in Canada. 2002. Retrieved 19 April 2007.
  56. McClain, Craig R.; Balk, Meghan A.; Benfield, Mark C.; Branch, Trevor A.; Chen, Catherine; Cosgrove, James; Dove, Alistair D.M.; Gaskins, Leo; Helm, Rebecca R.; Hochberg, Frederick G.; Lee, Frank B.; Marshall, Andrea; McMurray, Steven E.; Schanche, Caroline; Stone, Shane N.; Thaler, Andrew D. (13 January 2015). "Sizing ocean giants: patterns of intraspecific size variation in marine megafauna". PeerJ. 3: e715. doi:10.7717/peerj.715. PMC 4304853. PMID 25649000.
  57. Roston, Rachel A. (2013). "Anatomy and Age Estimation of an Early Blue Whale (Balaenoptera musculus) Fetus". The Anatomical Record. 296 (4): 709–722. doi:10.1002/ar.22678. PMID 23447333. Retrieved 23 November 2024.
  58. ^ "Blue whale". National Geographic. Archived from the original on 7 June 2022. Retrieved 3 March 2023.
  59. Purves, P. E. (1955). "The wax plug in the external auditory meatus of the". Discovery Reports. 27: 259–273.
  60. Gabriele, C. M.; Lockyer, C.; Straley, J. M.; Juasz, C. M.; Kato, H. (2010). "Sighting history of a naturally marked humpback whale (Megaptera novaeangliae) suggests ear plug growth layer groups are deposited annually". Marine Mammal Science. 26 (2): 443–450. Bibcode:2010MMamS..26..443G. doi:10.1111/j.1748-7692.2009.00341.x.
  61. Lockyer, C. (1984). "Age Determination by means of the ear plug in baleen whales". Report of the International Whaling Commission. 34: 692–696.
  62. "Blue whale". Whale and Dolphin Conservation. Archived from the original on 3 March 2023. Retrieved 3 March 2023.
  63. ^ Branch, T. A. (2008). "Biological parameters for pygmy blue whales". International Whaling Commission Document. SC/60/SH6: 13.
  64. Perrin, W. F.; Donovan, G. P. (1984). "Report of the Workshop". In Perrin, W. F.; Donovan, G. P.; DeMaster, D. P. (eds.). Reproduction in whales, dolphin and porpoises. Cambridge, UK: International Whaling Commission.
  65. ^ "Blue Whale". NOAA Fisheries. Retrieved 11 November 2019.
  66. Abrahms, B.; Hazen, E. L.; Aikens, E. O.; Savoca, M. S.; Goldbogen, J. A.; Goldbogen, S. J.; Jacox, M. G.; Irvine, L. M.; Palacios, D. M.; Mate, B. R. (2019). "Memory and resource tracking drive blue whale migrations". Proceedings of the National Academy of Sciences. 116 (12): 5582–5587. Bibcode:2019PNAS..116.5582A. doi:10.1073/pnas.1819031116. PMC 6431148. PMID 30804188.
  67. Geijer, C. K.; Notarbartolo di Sciara, G.; Panigada, S. (2016). "Mysticete migration revisited: Are Mediterranean fin whales an anomaly?". Mammal Review. 46 (4): 284–296. doi:10.1111/mam.12069.
  68. Segre, P. S.; Potvin, J; Cade, D. E.; Calambokidis, J; Di Clemente , J; Fish, F. E.; Friedlaender, A. S.; Gough, W. T.; Kahane-Rapport, S. R.; Oliveira, C; Parks, S. E.; Penry, G. S.; Simon, M; Stimpert, A. K.; Wiley, D. N.; Bierlich, K. C.; Madsen, P. T.; Goldbogen, J. A. (2020). "Energetic and physical limitations on the breaching performance of large whales". Physics of Living Systems. 9. doi:10.7554/eLife.51760. PMC 7065846. PMID 32159511.
  69. ^ Goldbogen, J. A.; Calambokidis, J.; Oleson, E.; Potvin, J.; Pyenson, N. D.; Schorr, G.; Shadwick, R. E. (2011). "Mechanics, hydrodynamics and energetics of blue whale lunge feeding: Efficiency dependence on krill density". Journal of Experimental Biology. 214 (1): 131–46. Bibcode:2011JExpB.214..131G. doi:10.1242/jeb.048157. PMID 21147977.
  70. Croll, D. A.; Aceveo-Gutierrez, A.; Tershy, B. R.; Urban-Ramirez, J. (2010). "The diving behavior of blue and fin whales: Is dive duration shorter than expected based on oxygen stores?". Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology. 129 (4): 797–809. doi:10.1016/S1095-6433(01)00348-8. PMID 11440866.
  71. Owen, K.; Jenner, C. S.; Jenner, M.-N. M.; Andrews, R. D. (2016). "A week in the life of a pygmy blue whale: migratory dive depth overlaps with large vessel drafts". Animal Biotelemetry. 4 (17): 1–11. Bibcode:2016AnBio...4...17O. doi:10.1186/s40317-016-0109-4.
  72. Goldbogen, J. A.; Cade, D. E.; Calambokidis, J.; Czapanskiy, M. F.; Fahlbusch, J.; Friedlaender, A. S.; Gough, W. T.; Kahane-Rapport, S. R.; Savoca, M. S.; Ponganis, K. V.; Ponganis, P. J. (2019). "Extreme bradycardia and tachycardia in the world's largest animal". Proceedings of the National Academy of Sciences. 116 (50): 25329–25332. Bibcode:2019PNAS..11625329G. doi:10.1073/pnas.1914273116. PMC 6911174. PMID 31767746.
  73. ^ Fossette, S.; Abrahms, B.; Hazen, E. L.; Bograd, S. J.; Zilliacus, K. M.; Calambokidis, J.; Burrows, J. A.; Goldbogen, J. A.; Harvey, J. T.; Marinovic, B.; Tershy, B.; Croll, D. A. (2017). "Resource partitioning facilitates coexistence in sympatric cetaceans in the California Current". Ecology and Evolution. 7 (1): 9085–9097. Bibcode:2017EcoEv...7.9085F. doi:10.1002/ece3.3409. PMC 5677487. PMID 29152200.
  74. Goldbogen, J. A.; Calambokidis, J.; Friedlaender, A. S.; Francis, J.; DeRuiter, A. L.; Stimpert, A. K.; Falcone, E.; Southall, B. L. (2012). "Underwater acrobatics by the world's largest predator: 360° rolling manoeuvres by lunge-feeding blue whales". Biology Letters. 9 (1): 20120986. doi:10.1098/rsbl.2012.0986. PMC 3565519. PMID 23193050.
  75. Barlow, Dawn R. (2023). "Shaped by their Environment: Variation in Blue Whale Morphology Across Three Productive Coastal Ecosystems". Integrative Organismal Biology. Retrieved 23 November 2024.
  76. Hazen, E. L.; Friedlaender, A. S.; Goldbogen, J. A. (2015). "Blue whales ("Balaenoptera musculus") optimize foraging efficiency by balancing oxygen use and energy gain as a function of prey density". Science Advances. 1 (9): e1500469. Bibcode:2015SciA....1E0469H. doi:10.1126/sciadv.1500469. PMC 4646804. PMID 26601290.
  77. Brodie, P. F. (1975). "Cetacean energetics, an overview of intraspecific size variation". Ecology. 56 (1): 152–161. Bibcode:1975Ecol...56..152B. doi:10.2307/1935307. JSTOR 1935307.
  78. Croll, D. A.; Kudela, R.; Tershy, B. R. (2006). "Ecosystem impact of the decline of large whales in the North Pacific". In Estes, J. A. (ed.). Whales, Whaling and Ocean Ecosystems. Berkeley, CA: University of California Press. pp. 202–214.
  79. ^ de Vos, Asha; Faux, Cassandra E.; Marthick, James; Dickinson, Joanne; Jarman, Simon N. (6 April 2018). "New Determination of Prey and Parasite Species for Northern Indian Ocean Blue Whales". Frontiers in Marine Science. 5. doi:10.3389/fmars.2018.00104. ISSN 2296-7745.
  80. Fiedler, Paul C.; Reilly, Stephen B.; Hewitt, Roger P.; Demer, David; Philbrick, Valerie A.; Smith, Susan; Armstrong, Wesley; Croll, Donald A.; Tershy, Bernie R.; Mate, Bruce R. (1 August 1998). "Blue whale habitat and prey in the California Channel Islands". Deep Sea Research Part II: Topical Studies in Oceanography. 45 (8): 1781–1801. Bibcode:1998DSRII..45.1781F. doi:10.1016/S0967-0645(98)80017-9. ISSN 0967-0645.
  81. Hardin, G. (1960). "The competitive exclusion principle". Science. 131 (3409): 1292–1297. Bibcode:1960Sci...131.1292H. doi:10.1126/science.131.3409.1292. PMID 14399717. S2CID 18542809.
  82. Hutchinson, G. E. (1961). "The Paradox of the Plankton". The American Naturalist. 95 (882): 137–145. Bibcode:1961ANat...95..137H. doi:10.1086/282171. S2CID 86353285.
  83. Pianka, E. R. (1974). "Niche overlap and diffuse competition". Proceedings of the National Academy of Sciences. 71 (5): 2141–2145. Bibcode:1974PNAS...71.2141P. doi:10.1073/pnas.71.5.2141. PMC 388403. PMID 4525324.
  84. Doniol-Valcroze, T. (2008). Habitat selection and niche characteristics of rorqual whales in the northern Gulf of St. Lawrence (Canada) (PhD). Montreal, Canada: McGill University.
  85. Friedlaender, A. S.; Goldbogen, J. A.; Hazen, E. L.; Calambokidis, J.; Southall, B. L. (2015). "Feeding performance by sympatric blue and fin whales exploiting a common prey resource". Marine Mammal Science. 31 (1): 345–354. Bibcode:2015MMamS..31..345F. doi:10.1111/mms.12134.
  86. Santora, J. A.; Reiss, C. S.; Loeb, V. J.; Veit, R. R. (2010). "Spatial association between hotspots of baleen whales and demographic patterns of Antarctic krill Euphausia superba suggests size-dependent predation". Marine Ecology Progress Series. 405: 255–269. Bibcode:2010MEPS..405..255S. doi:10.3354/meps08513.
  87. Melica, Valentina (2020). "Reproduction and Stress Response Endocrinology in Blue (Balaenoptera musculus) and Gray (Eschrichtius robust) Whales" (PDF). Scholarworks Alaska. Retrieved 23 November 2024.
  88. ^ Sears, R.; Perrin, W. F. (2018). "Blue Whale: "Balaenoptera musculus"". In Würsig, B.; Thewissen, J. G. M.; Kovacs, K. M. (eds.). Encyclopedia of marine mammals. London, UK: Academic Press. pp. 110–114.
  89. Ichihara T. (1964). "The pygmy blue whale, Balaenoptera musculus brevicauda, a new subspecies from Antarctic". Norsk. Hvalf. Tid. 6.
  90. Sazhinov E. G. (1970). "The onset of sexual and physical maturity for pygmy blue whales (Balaenoptera musculus brevicauda. Ichinara. 1966)". Whales of the Southern Hemisphere (29): 34–40.
  91. Branch, T. A.; Mikhalev, Y. A. (2008). "Regional differences in length at sexual maturity for female blue whales based on recovered Soviet whaling data". Marine Mammal Science. 24 (3): 690–703. Bibcode:2008MMamS..24..690B. doi:10.1111/j.1748-7692.2008.00214.x.
  92. Sears, R.; Ramp, C.; Douglas, A. B.; Calambokidis, J. (2013). "Reproductive parameters of eastern North Pacific blue whales Balaenoptera musculus". Endangered Species Research. 22 (1): 23–31. doi:10.3354/esr00532.
  93. ^ 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.
  94. Sergeant, D. E. (1969). "Feeding rates of Cetacea". Fiskeridir. SKR. Havundersok. 15: 246–258.
  95. Lockyer, C. (1984). "Review of baleen whale (Mysticeti) reproduction and implications for management". Report of the International Whaling Commission. 6: 27–50.
  96. Oftedal, O. T. (1997). "Lactation in whales and dolphins: Evidence of divergence between baleen- and toothed-species". Journal of Mammary Gland Biology and Neoplasia. 2 (3): 205–230. doi:10.1023/A:1026328203526. PMID 10882306. S2CID 19588882.
  97. "Exclusive Video May Show Blue Whale Calf Nursing". National Geographic. 2 March 2016. Archived from the original on 31 December 2019. Retrieved 20 December 2019.
  98. Yamato, M.; Ketten, D. R.; Arruda, J.; Cramer, S. (2008). "Biomechanical and structural modeling of hearing in baleen whales". Bioacoustics. 17 (1–3): 100–102. Bibcode:2008Bioac..17..100Y. doi:10.1080/09524622.2008.9753781. S2CID 85314872.
  99. Stafford, K. M.; Fox, G. C.; Clark, D. S. (1998). "Long-range acoustic detection and localization of blue whale calls in the northeast Pacific Ocean". Journal of the Acoustical Society of America. 50 (4): 1193–1198. Bibcode:1998ASAJ..104.3616S. doi:10.1121/1.423944. PMID 9857519.
  100. McDonald, M. A.; Mesnick, S. L.; Hildebrand, J. A. (2023). "Biogeographic characterization of blue whale song worldwide: Using song to identify populations". Journal of Cetacean Research and Management. 8: 55–66. doi:10.47536/jcrm.v8i1.702. S2CID 18769917.
  101. 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. p. 442.
  102. ^ 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.
  103. ^ 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.
  104. 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.
  105. ^ 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.
  106. 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.
  107. 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.
  108. ^ 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.
  109. 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.
  110. ^ 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.
  111. ^ 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.
  112. ^ 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.
  113. Sears, R. (1990). "The Cortez blues". Whalewatcher. 24: 12–15.
  114. Mehta, A. V.; Allen, J. M.; Constantine, R.; Garrigue, C.; Jann, B.; Jenner, C.; Marx, M. K.; Matkin, C. O.; Mattila, D. K.; Minton, G.; Mizroch, S. A.; Olavarría, C.; Robbins, J.; Russell, K. G.; Seton, R. E. (2007). "Baleen whales are not important as prey for orcas (Orcinus orca) in high latitudes". Marine Ecology Progress Series. 348: 297–307. doi:10.3354/meps07015. hdl:1912/4520.
  115. Cotton, B. C. (1944). "Killer whales in South Australia". Australian Zoologist. 10: 293–294.
  116. Tarpy, C. (1979). "Killer whale attack!". National Geographic Magazine. 155: 542–545.
  117. Ford, J. K. B.; Reeves, R. (2008). "Fight or flight: antipredator strategies of baleen whales". Mammal Review. 38 (1): 50–86. doi:10.1111/j.1365-2907.2008.00118.x.
  118. Pitman, R.; Fearnbach, H.; LeDuc, R.; Gilpatrick, J. W.; Ford, J. K. B.; Balance, L. T. (2023). "Killer whales preying on a blue whale calf on the Costa Rica Dome: Genetics, morphometrics, vocalizations and composition of the group". Journal of Cetacean Research and Management. 9 (2): 151–158. doi:10.47536/jcrm.v9i2.683. S2CID 257138804.
  119. "Killer Whales Bully Lone Blue Whale in Rare Video". Live Science. 5 March 2014. Retrieved 23 December 2019.
  120. "Killer Whales Attacked a Blue Whale—Here's the Surprising Reason Why". National Geographic. 25 May 2017. Archived from the original on 31 December 2019. Retrieved 23 December 2019.
  121. Totterdell, J. A.; Wellard, R.; Reeves, I. M.; Elsdon, B.; Markovic, P.; Yoshida, M.; Fairchild, A.; Sharp, G.; Pitman, R. (2022). "The first three records of killer whales (Orcinus orca) killing and eating blue whales (Balaenoptera musculus)". Marine Mammal Science. 38 (3): 1286–1301. Bibcode:2022MMamS..38.1286T. doi:10.1111/mms.12906. S2CID 246167673.
  122. Hermosilla, C; Silva, L. M. R.; Prieto, R; Kleinertz, S; Taubert, A; Silva, M. A. (2015). "Endo- and ectoparasites of large whales (Cetartiodactyla: Balaenopteridae, Physeteridae): Overcoming difficulties in obtaining appropriate samples by non- and minimally-invasive methods". International Journal for Parasitology: Parasites and Wildlife. 4 (3): 414–420. Bibcode:2015IJPPW...4..414H. doi:10.1016/j.ijppaw.2015.11.002. PMC 4699982. PMID 26835249.
  123. Gambell, R. (1979). "The blue whale". Biologist. 26: 209–215.
  124. Best, P. B. (1993). "Increase rates in severely depleted stocks of baleen whales". ICES J. Mar. Sci. 50 (2): 169–186. Bibcode:1993ICJMS..50..169B. doi:10.1006/jmsc.1993.1018.
  125. Sigurjónsson, J. (1988). "Operational factors of the Icelandic large whale fishery". Reports of the International Whaling Commission. 38: 327–333.
  126. "Part 17 – Conservation of Endangered Species and Other Fish or Wildlife (First List of Endangered Foreign Fish and Wildlife as Appendix A)" (PDF). U.S. Fish & Wildlife Service. 2 June 1970. Archived (PDF) from the original on 9 October 2022. Retrieved 24 December 2019.
  127. "Appendices". Convention on International Trade in Endangered Species of Wild Fauna and Flora. 26 November 2019. Retrieved 24 December 2019.
  128. "Convention on the Conservation of Migratory Species of Wild Animals" (PDF). United Nations Environment Programme. 23 June 1979. Archived from the original (PDF) on 2 May 2020. Retrieved 24 December 2019.
  129. Samaran, F.; Stafford, K. M.; Branch, T. A.; Gedamke, J.; Royer, Y.-J.; Dziak, R. P.; Guinet, C. (2013). "Seasonal and geographic variation of southern blue whale subspecies in the Indian Ocean". PLOS ONE. 8 (8): e71561. Bibcode:2013PLoSO...871561S. doi:10.1371/journal.pone.0071561. PMC 3742792. PMID 23967221.
  130. "Blue Whale". International Union for Conservation. 6 December 2018. Retrieved 24 December 2019.
  131. Darby, Andrew (2009). Harpoon Into the Heart of Whaling. Hachette Books. pp. 38–39. ISBN 9780786732005.
  132. "Blue whale – Balaenoptera musculus". International Whaling Commission. Retrieved 25 February 2022.
  133. Ivashchenko, Y.; Clapham, P. J.; Brownell, R. (2011). "Soviet Illegal Whaling: The Devil and the Details" (PDF). Marine Fisheries Review. 73 (1): 1–19. Archived from the original (PDF) on 22 March 2022. Retrieved 26 January 2023.
  134. ^ Berman-Kowalewski, M.; Gulland, F.; Wilkin, S.; Calambokidis, J.; Mate, B.; Cordaro, J.; Rotstein, D.; St. Leger, J.; Collins, P.; Fahy, K.; Dover, S. (2010). "Association between blue whale mortality and ship strikes along the California coast". Aquatic Mammals. 36 (1): 59–66. doi:10.1578/AM.36.1.2010.59. S2CID 86304413.
  135. Abramson, L.; Polefka, S.; Hastings, S.; Bor, K. (2009). Reducing the Threat of Ship Strikes on Large Cetaceans in the Santa Barbara Channel Region and Channel Islands National Marine Sanctuary: Recommendations and Case Studies (Report). Channel Islands National Marine Sanctuary Advisory Council. pp. 1–73.
  136. de Vos, A.; Brownell, R. L. Jr.; Tershy, B. R.; Croll, D. A. (2016). "Anthropogenic threats and conservation needs of blue whales, "Balaenoptera musculus indica", around Sri Lanka". J. Mar. Biol. 2016 (8420846): 1–12. doi:10.1155/2016/8420846.
  137. Priyadarshana, T.; Randage, R.; Alling, A.; Calderan, S.; Gordon, J.; Leaper, R.; Porter, L. (2015). An update on work related to ship strike risk to Blue whales off southern Sri Lanka (Report). Vol. SC66A. The International Whaling Commission.
  138. Randage, S. M.; Alling, A.; Currier, K.; Heywood, E. (2023). "Review of the Sri Lanka blue whale (Balaenoptera musculus) with observations on its distribution in the shipping lane". Journal of Cetacean Research and Management. 14: 43–49. doi:10.47536/jcrm.v14i1.522. S2CID 46399716.
  139. Brownell, R. L. Jr.; Cabrera, E.; Galletti-Vernazzani, B. (2014). Dead blue whale in Puerto Montt, Chile: Another case of ship collision mortality (Report). Vol. SC/65b/HIM08. International Whaling Commission.
  140. International whaling Commission (2017). Report of the Scientific Committee (Report). International Whaling Commission. p. 136.
  141. Redfern, J. V.; McKenna, M. F.; Moore, T. J.; Calambokidis, J.; Deangelis, M. L.; Becker, E. A.; Barlow, J.; Forney, K. A.; Fiedler, P. C.; Chivers, S. J. (2013). "Assessing the risk of ships striking large whales in marine spatial planning". Conservation Biology. 22 (2): 292–302. Bibcode:2013ConBi..27..292R. doi:10.1111/cobi.12029. PMID 23521668. S2CID 17833403.
  142. Dransfield, A.; Hines, E.; McGowan, J.; Holzman, B.; Nur, N.; Elliott, M.; Howar, J.; Jacncke, J. (2014). "Where the whales are: using habitat modeling to support changes in shipping regulations within National Marine Sanctuaries in Central California". Endanger Species Res. 26 (1): 39–57. doi:10.3354/esr00627.
  143. Carretta, J. V.; Muto, M. M.; Greenman, J.; Wilkinson, K.; Viezbicke, J.; Jannot, J. (2017). Sources of human-related injury and mortality for U.S. Pacific west coast marine mammal stock assessments, 2011– 2015 (Report). Vol. PSRG-2017-07. NOAA.
  144. NMFS (2017). National Report on Large Whale Entanglements (Report). NOAA.
  145. de Vos, A. (2015). "Marine life on the line". In Braun, D. (ed.). Deepwater Horizon oil spill: Final Programmatic Damage Assessment and Restoration Plan and Final Programmatic Environmental Impact Statement. National Geographic. p. 685.
  146. Southall, B. L.; Hatch, L.; Scholik-Schlomer, A.; Bergmann, T.; Jasny, M.; Metcalf, K.; Weilgart, L.; Wright, A. J.; Perera, M. E. (2018). "Reducing noise from large commercial ships: progress and partnerships". Proc. Mar. Saf. Sec. Council. 1: 58–65.
  147. Wiggins, S. M.; Oleson, E. M.; Hildebrand, J. A. (2001). "Blue whale call intensity varies with ambient noise level". Journal of the Acoustical Society of America. 110 (5): 2771. Bibcode:2001ASAJ..110.2771W. doi:10.1121/1.4777708.
  148. McKenna, M. F.; Ross, D.; Wiggins, S. M.; Hildebrand, J. A. (2012). "Underwater radiated noise from modern commercial ships". The Journal of the Acoustical Society of America. 131 (1): 92–103. Bibcode:2012ASAJ..131...92M. doi:10.1121/1.3664100. PMID 22280574. S2CID 9474116.
  149. Szesciorka, A. R.; Allen, A. N.; Calambokidis, J.; Fahlbusch, J.; McKenna, M. F.; Southall, B. L. (2019). "A case study of a near vessel strike of a blue whale: perceptual cues and fine-scale aspects of behavioral avoidance". Front. Mar. Sci. 6 (761): 1–10. doi:10.3389/fmars.2019.00761.
  150. Di Iorio, L.; Clark, C. W. (2009). "Exposure to seismic survey alters blue whale acoustic communication". Biology Letters. 6 (1): 1–4.
  151. McDonald, M. A.; Hildebrand, J. A.; Webb, S. C. (1995). "Blue and fin whales observed on a seafloor array in the Northeast Pacific". Journal of the Acoustical Society of America. 98 (2): 712–721. Bibcode:1995ASAJ...98..712M. doi:10.1121/1.413565. PMID 7642810. S2CID 3829165.
  152. Melcón, M. L.; Cummins, A. J.; Kerosky, S. M.; Roche, L. K.; Wiggins, S. M.; Hildebrand, J. A. (2012). "Blue Whales Respond to Anthropogenic Noise". PLOS ONE. 7 (2): e32681. Bibcode:2012PLoSO...732681M. doi:10.1371/journal.pone.0032681. PMC 3290562. PMID 22393434.
  153. Southall, B. L.; DeRuiter, S. L.; Friedlaender, A.; Stimpert, A. K.; Goldbogen, J. A.; Hazen, E.; Casey, C.; Fregosi, S.; Cade, D. E.; Allen, A. N.; Harris, C. M.; Schorr, G.; Moretti, D. (2019). "Behavioral responses of individual blue whales (Balaenoptera musculus) to mid-frequency military sonar". The Journal of Experimental Biology. 222 (jeb190637): jeb190637. Bibcode:2019JExpB.222B0637S. doi:10.1242/jeb.190637. hdl:10023/19592. PMID 30833464.
  154. O'Shea, T. J.; Brownell, R. L. (1994). "Organochlorine and metal contaminants in baleen whales:a review and evaluation of conservation implications". Science of the Total Environment. 154 (2–3): 179–200. Bibcode:1994ScTEn.154..179O. doi:10.1016/0048-9697(94)90087-6. PMID 7973606.
  155. Trumble, S. J.; Robinson, E. M.; Berman-Kowalewski, M.; Potter, C. W.; Usenko, S. (2013). "Blue whale earplug reveals lifetime contaminant exposure and hormone profiles". Proceedings of the National Academy of Sciences. 110 (42): 16922–16926. Bibcode:2013PNAS..11016922T. doi:10.1073/pnas.1311418110. PMC 3801066. PMID 24043814.
  156. Metcalfe, C. D.; Koenig, B. G.; Metcalfe, T. L.; Paterson, G.; Sears, R. (2004). "Intra- and inter-species differences in persistent organic contaminants in the blubber of blue whales and humpback whales from the Gulf of St. Lawrence, Canada". Marine Environmental Research. 57 (4): 245–260. Bibcode:2004MarER..57..245M. doi:10.1016/j.marenvres.2003.08.003. PMID 14749058.

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Extant Cetacea species
Parvorder Mysticeti (Baleen whales)
Balaenidae
Balaena
Eubalaena
(Right whales)
Balaenopteridae
(Rorquals)
Balaenoptera
Eschrichtius
Megaptera
Cetotheriidae
Caperea
Parvorder Odontoceti (Toothed whales)
Delphinidae
(Oceanic dolphins)
Cephalorhynchus
Delphinus
Feresa
Globicephala
(Pilot whales)
Grampus
Lagenodelphis
Lagenorhynchus
Lissodelphis
(Right whale dolphins)
Orcaella
Orcinus
Peponocephala
Pseudorca
Sotalia
Sousa
(Humpback dolphins)
Stenella
Steno
Tursiops
(Bottlenose dolphins)
Monodontidae
Delphinapterus
Monodon
Phocoenidae
(Porpoises)
Neophocoena
(Finless porpoises)
Phocoena
Phocoenoides
Physeteridae
Physeter
Kogiidae
Kogia
Iniidae
Inia
Lipotidae
Lipotes
Platanistidae
Platanista
Pontoporiidae
Pontoporia
Ziphiidae
(Beaked whales)
Berardius
Hyperoodon
(Bottlenose whales)
Indopacetus
Mesoplodon
(Mesoplodont whales)
Tasmacetus
Ziphius
Taxon identifiers
Balaenoptera musculus
Balaena musculus
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