Pilot whale: Difference between revisions
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{{Short description|Genus of dolphins in the order Cetacea}} |
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{{Use dmy dates|date=September 2013}}{{good article}} |
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{{Use dmy dates|date=July 2019}} |
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{{Taxobox |
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{{Good article}} |
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| name = Pilot whales |
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{{Automatic taxobox |
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| name = Pilot whales |
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| fossil_range = [[Pliocene]] to recent |
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| image = Pilot whale.jpg |
| image = Pilot whale.jpg |
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| image_width = 250px |
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| image2 = Short-finned pilot whale size.svg |
| image2 = Short-finned pilot whale size.svg |
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| image2_caption = Size of short-finned pilot whale compared to an average human |
| image2_caption = Size of short-finned pilot whale compared to an average human |
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| taxon = Globicephala |
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| authority = [[René Lesson|Lesson]], 1828 |
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| status_system =iucn3.1 |
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| type_species = ''[[Globicephala melas|Delphinus globiceps]]''<ref>{{MSW3|id=14300050}}</ref> |
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| status_ref =<ref name="icun"/><ref name="icun2"/> |
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| type_species_authority = Cuvier, 1812 |
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| regnum = [[Animal]]ia |
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| phylum = [[Chordate|Chordata]] |
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| classis = [[Mammal]]ia |
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| ordo = [[Cetacea]] |
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| subordo = [[Odontoceti]] |
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| familia = [[Delphinidae]] |
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| genus = '''''Globicephala''''' |
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| range_map = cetacea_range_map_Pilot_Whale.png |
| range_map = cetacea_range_map_Pilot_Whale.png |
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| range_map_caption = {{leftlegend|#0000FF|Exclusive range of [[Globicephala macrorhynchus|short-finned pilot whale]]|outline=gray}}{{leftlegend|#75C173|Exclusive range of [[Globicephala melas|long-finned pilot whale]]|outline=gray}}{{leftlegend|#3F8B73|Regions of [[sympatry]]|outline=gray}} |
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| range_map_width = 250px |
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| synonyms = ''Globicephalus'' |
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| range_map_caption = Green: long-finned range; blue: short-finned |
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| subdivision_ranks = Species |
| subdivision_ranks = Species |
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| subdivision = ''[[Globicephala macrorhynchus]]''<br/>''[[Globicephala melas]]'' |
| subdivision = ''[[Globicephala macrorhynchus]]''<br/>''[[Globicephala melas]]'' |
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}} |
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'''Pilot whales''' are [[cetacean]]s belonging to the [[genus]] '''''Globicephala'''''. The two [[Extant taxon|extant]] species are the [[long-finned pilot whale]] (''G. melas'') and the [[short-finned pilot whale]] (''G. macrorhynchus''). The two are not readily |
'''Pilot whales''' are [[cetacean]]s belonging to the [[genus]] '''''Globicephala'''''. The two [[Extant taxon|extant]] species are the [[long-finned pilot whale]] (''G. melas'') and the [[short-finned pilot whale]] (''G. macrorhynchus''). The two are not readily distinguishable at sea, and analysis of the skulls is the best way to distinguish between the species. Between the two species, they range nearly worldwide, with long-finned pilot whales living in colder waters and short-finned pilot whales living in tropical and subtropical waters. Pilot whales are among the largest of the [[oceanic dolphin]]s, exceeded in size only by the [[orca]]. They and other large members of the dolphin family are also known as [[blackfish]]. |
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Pilot whales |
Pilot whales feed primarily on squid, but will also hunt large [[demersal fish]] such as [[cod]] and [[turbot]]. They are highly social and may remain with their birth [[wikt:pod#Noun|pod]] throughout their lifetime. Short-finned pilot whales are one of the few non-primate mammal species in which females go through [[menopause]], and postreproductive females continue to contribute to their pod. Pilot whales are notorious for [[Cetacean stranding|stranding]] themselves on beaches, but the reason behind this is not fully understood. Marine biologists have shed some light on the matter, suggesting that it is due to the mammals inner ear (their principal navigational sonar) being damaged from noise pollution in the ocean, such as from cargo ships or military exercises.<ref>{{cite web | url=https://kaltura.uga.edu/media/t/1_b93ma55v/ | title=Sonic Sea|publisher=Brown Media Archives and Peabody Awards Collection, University of Georgia}}</ref> The [[conservation status]] of short-finned and long-finned pilot whales has been determined to be [[least concern]]. |
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==Naming== |
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==Taxonomy and naming== |
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The animals were named "pilot whales" because pods were believed to be "piloted" by a leader.<ref name="Perrin"/><ref name="Ridgeway 1998"/> They are also called "pothead whales" and "blackfish". The genus name is a combination of the Latin word ''globus'' ("round ball" or "globe") and the Greek word ''Kephale'' ("head").<ref name="Perrin"/><ref name="Ridgeway 1998"/> |
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Pilot whales are classified into two species: |
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*[[Long-finned pilot whale]] (''Globicephala melas'') |
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*[[Short-finned pilot whale]] (''Globicephala macrorhynchus''). |
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[[File:Globicephala etruriae.JPG|thumb|left|Jaw of the extinct species ''Globicephala etruriae'']] |
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The short-finned pilot whale was described, from skeletal materials only, by [[John Edward Gray]] in 1846. He presumed from the skeleton that the whale had a large beak. The long-finned pilot whale was first classified by [[Thomas Stewart Traill]] in 1809 as ''Delphinus melas''.<ref>Traill, T. S. (1809). "Description of a new species of whale, ''Delphinus melas''". In a letter from Thomas Stewart Traill, M.D. to Mr. Nicholson. ''Journal of Natural Philosophy, Chemistry, and the Arts'' 1809:81–83.</ref> Its scientific name was eventually changed to ''Globicephala melaena''. Since 1986, the [[specific name (zoology)|specific name]] of the long-finned pilot whale was changed to its original form ''melas''.<ref>Starting with: Jones Jr, J .K., Carter, D.C., Genoways, H.H., Hoffman, R.S., Rice, D.W. Jones, C. (1986) "Revised checklist of North American mammals north of Mexico", ''Occ Papers Mus Texas Tech Univ'' 107:5</ref> Other species classifications have been proposed but only two have been accepted.<ref name="van Bree 1971">{{cite journal|author=van Bree, P.J.H. |year=1971|title=On ''Globicephala seiboldi'', Gray 1846, and other species of pilot whales. (Notes on cetacean, ''Delphinoidea'' III)|journal=Beaufortia|volume=19|pages=79–87}}</ref> There exist geographic forms of short-finned pilot whales off the east coast of Japan,<ref>{{cite journal|author=Kasuya, T., Sergeant, D. E., Tanaka, K. |year=1986|title=Segregation of two forms of short-finned pilot whales off the Pacific coast of Japan|journal=Scientific Reports of the Whales Research Institute|volume= 39|pages=77–90}}</ref> which comprise genetically isolated stocks.<ref>{{cite journal|author=Wada, S. |year=1988|title=Genetic differentiation between two forms of short-finned pilot whales off the Pacific coast of Japan|journal=Sci Rep Whales Res Inst|volume=39|pages=91–101}}</ref> |
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==Taxonomy and evolution== |
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Fossils of an extinct relative, ''Globicephala baerreckii'', have been found in [[Pleistocene]] deposits in Florida.<ref name="Perrin"/> Another ''Globicephala'' dolphin was discovered in [[Pliocene]] strata in Tuscany, Italy, and was named ''G. eturia''.<ref name="Perrin"/> The pilot whales were also close relatives of the extinct [[blunt-snouted dolphin]]. Close living relatives of the pilot whales are the [[melon-headed whale]], the [[pygmy killer whale]], the [[false killer whale]], and [[Risso's dolphin]]. |
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[[File:Globicephala etruriae.JPG|thumb|left|Jaw of the extinct species ''[[Globicephala etruriae]]'']] |
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Pilot whales are classified into two species; the [[long-finned pilot whale]] (''Globicephala melas'') and the [[short-finned pilot whale]] (''G. macrorhynchus''). The short-finned pilot whale was described, from skeletal materials only, by [[John Edward Gray]] in 1846. He presumed from the skeleton that the whale had a large beak. The long-finned pilot whale was first classified by [[Thomas Stewart Traill]] in 1809 as ''Delphinus melas''.<ref>{{cite journal | author = Traill T. S. | year = 1809 | title = Description of a new species of whale, ''Delphinus melas''". In a letter from Thomas Stewart Traill, M.D. to Mr. Nicholson | journal = Journal of Natural Philosophy, Chemistry, and the Arts | volume = 1809 | pages = 81–83 }}</ref> Its scientific name was eventually changed to ''Globicephala melaena''. Since 1986, the [[specific name (zoology)|specific name]] of the long-finned pilot whale was changed to its original form ''melas''.<ref>{{cite journal | last1 = Starting | first1= Jones Jr | last2 = Carter | first2 = D.C. | last3 = Genoways | first3 = H.H. | last4 = Hoffman | first4 = R.S. |last5 = Rice | first5 = D.W. | last6 = Jones | year = 1986 | title = Revised checklist of North American mammals north of Mexico | url = http://digitalcommons.unl.edu/museummammalogy/266/| journal = Occ Papers Mus Texas Tech Univ | volume = 107 | page = 5 }}</ref> Other species classifications have been proposed but only two have been accepted.<ref name="van Bree 1971">{{cite journal|author=van Bree, P.J.H. |year=1971|title=On ''Globicephala seiboldi'', Gray 1846, and other species of pilot whales. (Notes on cetacean, ''Delphinoidea'' III)|journal=Beaufortia|volume=19|pages=79–87}}</ref> There exist geographic forms of short-finned pilot whales off the east coast of Japan,<ref>{{cite journal|author=Kasuya, T., Sergeant, D. E., Tanaka, K. |year=1986|title=Segregation of two forms of short-finned pilot whales off the Pacific coast of Japan|url=http://www.icrwhale.org/pdf/SC03977-90.pdf|journal=Scientific Reports of the Whales Research Institute|volume= 39|pages=77–90}}</ref> which comprise genetically isolated stocks.<ref>{{cite journal|author=Wada, S. |year=1988|title=Genetic differentiation between two forms of short-finned pilot whales off the Pacific coast of Japan|journal=Sci Rep Whales Res Inst|volume=39|pages=91–101|url=http://www.icrwhale.org/pdf/SC03991-101.pdf}}</ref> |
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Fossils of an extinct relative, ''Globicephala baereckeii'', have been found in [[Pleistocene]] deposits in Florida.<ref name="Perrin"/> Another ''Globicephala'' dolphin was discovered in [[Pliocene]] strata in Tuscany, Italy, and was named ''[[Globicephala etruriae|G. etruriae]]''.<ref name="Perrin"/> Evolution of ''Tappanaga'', the endemic, larger form of short-finned pilots found in northern Japan, with similar characteristics to the whales found along [[Vancouver Island]] and northern USA coasts,<ref>[[:ja:日高敏隆|Hidaka T.]] [[:ja:粕谷俊雄|Kasuya T.]] [[:ja:伊沢紘生|Izawa K.]] [[:ja:川道武男|Kawamichi T.]] 1996. The encyclopaedia of animals in Japan (2) - Mammals 2. |
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The animals were named "pilot whales" because pods were believed to be "piloted" by a leader.<ref name="Perrin"/><ref name="Ridgeway 1998"/> They are also called "pothead whales" and "blackfish". The genus name is a combination of the Latin words ''globus'' ("round ball" or "globe") and ''kephale'' ("head").<ref name="Perrin"/><ref name="Ridgeway 1998"/> ''Melas'' is Greek for "black" and ''macrorhynchus'' comes from the Greek words ''macro'' ("enlarged") and ''rhynchus'' ("snout" or "beak"). |
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{{ISBN|9784582545524}} (9784582545517) (4582545521). [[:ja:平凡社|Heibonsha]]</ref> has indicated that the [[Evolution of cetaceans|geniture of this form could be caused]] by the extinction of long-finned pilots in north Pacific in the 12th century, where ''Magondou'', the smaller, southern type possibly filled the former [[Ecological niche|niche]]s of long-finned pilots, adapting and colonizing into colder waters.<ref>{{cite journal |author= Amano M. |year=2012 |title=みちのくの海のイルカたち(特集 みちのくの海と水族館の海棲哺乳類) |url= http://isanakai.web.fc2.com/journal/ |journal= Isana 56|pages=60–65 |publisher= Faculty of Fisheries of [[Nagasaki University|University of Nagasaki]], Isanakai |format=PDF |access-date= 2017-03-09 }}</ref> |
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==Description== |
==Description== |
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[[File:Walmuseum Húsavík - Skelett Grindwal.jpg|thumb|left|250px|Long-finned pilot whale skeleton]] |
[[File:Walmuseum Húsavík - Skelett Grindwal.jpg|thumb|left|250px|Long-finned pilot whale skeleton]] |
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Pilot whales are mostly dark grey, brown, or black, but have some light areas such as a grey saddle patch behind the [[dorsal fin]].<ref name="Ridgeway 1998"/> Other light areas are an anchor-shaped patch under the chin, a faint blaze marking behind the eye, a large marking on the belly, and a genital patch.<ref name="Ridgeway 1998"/> The dorsal fin is set forward on the back and sweeps backwards. A pilot whale is more robust than most dolphins |
Pilot whales are mostly dark grey, brown, or black, but have some light areas such as a grey saddle patch behind the [[dorsal fin]].<ref name="Ridgeway 1998"/> Other light areas are an anchor-shaped patch under the chin, a faint blaze marking behind the eye, a large marking on the belly, and a genital patch.<ref name="Ridgeway 1998"/> The dorsal fin is set forward on the back and sweeps backwards. A pilot whale is more robust than most dolphins and has a distinctive large, bulbous [[Melon (whale)|melon]].<ref name="Ridgeway 1998"/> Pilot whales' long, sickle-shaped flippers and tail stocks are flattened from side to side.<ref name="Ridgeway 1998"/> Male long-finned pilot whales develop more circular melons than females,<ref name="Ridgeway 1998"/> although this does not seem to be the case for short-finned pilot whales off the Pacific coast of Japan.<ref name="Yonekura 1980">{{cite journal|author=Yonekura, M., Matsui, S. & Kasuya, T. |year=1980|title=On the external characters of ''Globicephala macrorhynchus'' off Taiji, Pacific coast of Japan|journal=Sci. Rep. Inst|volume= 32|pages=67–95|issn=0083-9086}}</ref> |
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[[File:Pilot whale spyhop.jpg|thumb|250px|right| |
[[File:Pilot whale spyhop.jpg|thumb|250px|right|A pilot whale [[spyhopping]]]] |
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Long- and short-finned pilot whales are so similar, it is difficult to tell the two species apart.<ref name="Perrin"/> They were traditionally differentiated by the length of the pectoral flippers relative to total body length and the number of teeth.<ref name="van Bree 1971"/> The long-finned pilot whale was thought to have 9–12 teeth in each row and flippers one-fifth of total body length, compared to the short-finned pilot whale with its 7–9 teeth in each row and flippers one-sixth of total body length.<ref name="Ridgeway 1998"/> Studies of whales in the Atlantic showed much overlap in these characteristics between the species, making them [[Cline (biology)|cline]]s instead of distinctive features.<ref name="Ridgeway 1998"/> Thus, biologists have since used skull differences to distinguish the two species.<ref name="Perrin"/><ref name="Ridgeway 1998"/> The skull of the short-finned pilot whale has a shorter and broader rostum with a [[premaxilla]] that covers more of the [[maxilla]]. By contrast, the long-finned pilot whale's skull has a more elongated rostum and a more exposed maxilla. |
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Long-finned and short-finned pilot whales are so similar, it is difficult to tell the two species apart.<ref name="Perrin"/> They were traditionally differentiated by the length of the pectoral flippers relative to total body length and the number of teeth.<ref name="van Bree 1971"/> The long-finned pilot whale was thought to have 9–12 teeth in each row and flippers one-fifth of total body length, compared to the short-finned pilot whale with its 7–9 teeth in each row and flippers one-sixth of total body length.<ref name="Ridgeway 1998"/> Studies of whales in the Atlantic showed much overlap in these characteristics between the species, making them [[Cline (biology)|cline]]s instead of distinctive features.<ref name="Ridgeway 1998"/> Thus, biologists have since used skull differences to distinguish the two species.<ref name="Perrin"/><ref name="Ridgeway 1998"/> |
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The size and weight depend on the species, as long-finned pilot whales are generally larger than short-finned pilot whales.<ref name="Yonekura 1980"/><ref name="Kasuya1984"/> Their lifespans are about 45 years in males and 60 years in females for both species. Both species exhibit [[sexual dimorphism]]. Adult long-finned pilot whales reach a body length of approximately 6.5 m, with males being 1 m longer than females.<ref>{{cite journal|author=Bloch D, Lockyer C, Zachariassen M |year=1993|title=Age and growth parameters of the long-finned pilot whale off the Faroe Islands|journal=Rep Int Whal Comm|volume= 14|pages=163–208}}</ref> Their body mass reaches up to 1,300 kg in females and up to 2,300 kg in males.<ref name="Jefferson 2008">Jefferson, T. A, Webber, M. A., Pitman, R. L., (2008) ''[http://books.google.com/books?id=TwFUimDtz7sC&pg=PA557 Marine mammals of the world]''. Elsevier, Amsterdam.</ref> For short-finned pilot whales, adult females reach a body length of about 5.5 m, while males reach 7.2 m and may weigh up to 3,200 kg.<ref name="Jefferson 2008"/> |
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The size and weight depend on the species, as long-finned pilot whales are generally larger than short-finned pilot whales.<ref name="Yonekura 1980"/><ref name="Kasuya1984"/> Their lifespans are about 45 years in males and 60 years in females for both species. Both species exhibit [[sexual dimorphism]]. Adult long-finned pilot whales reach a body length of approximately 6.5 m, with males being 1 m longer than females.<ref>{{cite journal|vauthors=Bloch D, Lockyer C, Zachariassen M |year=1993|title=Age and growth parameters of the long-finned pilot whale off the Faroe Islands|journal=Rep. Int. Whal. Comm.|volume= 14|pages=163–208}}</ref> Their body mass reaches up to 1,300 kg in females and up to 2,300 kg in males.<ref name="Jefferson 2008">Jefferson, T. A, Webber, M. A., Pitman, R. L., (2008) ''[https://books.google.com/books?id=TwFUimDtz7sC&pg=PA557 Marine mammals of the world]''. Elsevier, Amsterdam.</ref> For short-finned pilot whales, adult females reach a body length of about 5.5 m, while males reach 7.2 m and may weigh up to 3,200 kg.<ref name="Jefferson 2008"/> |
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==Behavior and ecology== |
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==Distribution and habitat== |
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[[File:Short-finned Pilot Whale 1.jpg|thumb|275px|left|Pilot whale in the [[Gulf of California]]]] |
[[File:Short-finned Pilot Whale 1.jpg|thumb|275px|left|Pilot whale in the [[Gulf of California]]]] |
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Pilot whales can be found in oceans nearly worldwide. The long-finned pilot whale prefers slightly cooler waters than the short-finned |
Pilot whales can be found in oceans nearly worldwide, but data about current population sizes is deficient. The long-finned pilot whale prefers slightly cooler waters than the short-finned and is divided into two populations. The smaller group is found in a circumpolar band in the [[Southern Ocean]] from about [[20th parallel south|20]] to [[65th parallel south|65°S]]. It may be sighted off the coasts of [[Chile]], [[Argentina]], [[South Africa]], [[Australia]], and [[New Zealand]].<ref name=icun/> An estimated more than 200,000 individuals were in this population in 2006. The second, much larger, population inhabits the North [[Atlantic Ocean]], in a band from [[South Carolina]] in the United States across to the [[Azores]] and [[Morocco]] at its southern edge and from [[Newfoundland (island)|Newfoundland]] to [[Greenland]], Iceland, and northern [[Norway]] at its northern limit. This population was estimated at 778,000 individuals in 1989. It is also present in the western half of the [[Mediterranean Sea]].<ref name=icun/> |
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The short-finned pilot whale is less populous. It is found in temperate and tropical waters of the [[Indian Ocean|Indian]], Atlantic and [[Pacific Ocean|Pacific]] Oceans.<ref name=icun2/> Its population overlaps slightly with the long-finned pilot whale in the temperate waters of the North Atlantic and Southern Oceans.<ref name="Perrin">Olson, P.A. (2008) "Pilot whale '' Globicephala melas and G. muerorhynchus''" pp. 847–52 in ''[ |
The short-finned pilot whale is less populous. It is found in temperate and tropical waters of the [[Indian Ocean|Indian]], Atlantic and [[Pacific Ocean|Pacific]] Oceans.<ref name=icun2/> Its population overlaps slightly with the long-finned pilot whale in the temperate waters of the North Atlantic and Southern Oceans.<ref name="Perrin">Olson, P.A. (2008) "Pilot whale '' Globicephala melas and G. muerorhynchus''" pp. 847–52 in ''[https://books.google.com/books?id=2rkHQpToi9sC Encyclopedia of Marine Mammals]'', Perrin, W. F., Wursig, B., and Thewissen, J. G. M. (eds.), Academic Press; 2nd edition, {{ISBN|0-12-551340-2}}</ref> About 150,000 individuals are found in the eastern tropical Pacific Ocean. More than 30,000 animals are estimated in the western Pacific, off the coast of Japan. Pilot whales are generally nomadic, but some populations stay year-round in places such as [[Hawaii]] and parts of California.<ref name="Perrin"/> They prefer the waters of the [[Mid continental shelf|shelf break]] and [[continental slope|slope]].<ref name="Perrin"/> Once commonly seen off of Southern California, short-finned pilot whales disappeared from the area after a strong [[El Niño]] year in the early 1980s, according to the [[National Oceanic and Atmospheric Administration]].<ref name="nbclosangeles.com">{{Cite web|url=http://www.nbclosangeles.com/news/local/Whale-Watchers-Unexpectedly-Sight-Rare-Pilot-Whales-279684932.html|title = Whale Watchers Unexpectedly Sight Rare Pilot Whales| date=19 October 2014 }}</ref> In October 2014, crew and passengers on several boats spotted a pod of 50–200 off [[Dana Point, California]].<ref name="nbclosangeles.com"/> |
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==Behavior and life history== |
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===Foraging and parasites=== |
===Foraging and parasites=== |
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[[File:Globicephala melas Cape Breton group.jpg|thumb|250px|right|Pilot whales near [[Cape Breton Island]]]] |
[[File:Globicephala melas Cape Breton group.jpg|thumb|250px|right|Pilot whales near [[Cape Breton Island]]]] |
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Although pilot whales are not known to have many predators, possible threats come from humans and killer whales. |
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Both species eat primarily [[squid]].<ref name="Audubon">{{RefAudubonMarineMammals}}</ref> The whales make seasonal inshore and offshore movements in response to the dispersal of their prey.<ref name="Perrin"/> Fish that are consumed include [[Atlantic cod]], Greenland turbot, [[Atlantic mackerel]], [[Atlantic herring]], [[hake]], and [[spiny dogfish]] in the northwest Alantic.<ref name="Perrin"/> In the [[Faroe Islands]], whales mostly eat squid, but will also eat fish species such as [[greater argentine]] and [[blue whiting]]. However, Faroe whales do not seem to feed on [[cod]], [[herring]], or [[mackerel]] even when they are abundant.<ref>Desportes, G., Mouritsen, R. (1993) "Preliminary results on the diet of long-finned pilot whales off the Faroe Islands". ''Rep. int. Whal. Commn'' (special issue 14): 305–24.</ref> |
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Both species eat primarily [[squid]].<ref name="Audubon">{{RefAudubonMarineMammals}}</ref> The whales make seasonal inshore and offshore movements in response to the dispersal of their prey.<ref name="Perrin"/> Fish that are consumed include [[Atlantic cod]], Greenland turbot, [[Atlantic mackerel]], [[Atlantic herring]], [[hake]], and [[spiny dogfish]] in the northwest Atlantic.<ref name="Perrin"/> In the [[Faroe Islands]], whales mostly eat squid, but will also eat fish species such as [[greater argentine]] and [[blue whiting]]. However, Faroe whales do not seem to feed on [[cod]], [[herring]], or [[mackerel]], even when they are abundant.<ref>Desportes, G., Mouritsen, R. (1993) "Preliminary results on the diet of long-finned pilot whales off the Faroe Islands". ''Rep. Int. Whal. Comm.'' (special issue 14): 305–24.</ref> |
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Pilot whales generally take several breaths before diving for a few minutes. Feeding dives may last over ten minutes. They are capable of diving to depths of 600 meters, but most dives are to a depth of 30–60 m. Shallow dives tend to take place during the day, while deeper ones take place at night. When making deep dives, pilot whales often make fast sprints to catch fast-moving prey such as squid.<ref name="Natacha 2008">{{cite journal| |
Pilot whales generally take several breaths before diving for a few minutes. Feeding dives may last over ten minutes. They are capable of diving to depths of 600 meters, but most dives are to a depth of 30–60 m. Shallow dives tend to take place during the day, while deeper ones take place at night. When making deep dives, pilot whales often make fast sprints to catch fast-moving prey such as squid.<ref name="Natacha 2008">{{cite journal|author1=Aguilar de Soto, N. |author2=Johnson, M. P. |author3=Madsen, P. T. |author4=Díaz, F. |author5=Domínguez, I. |author6=Brito, A. |author7=Tyack, P. |year=2008|title=Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands)|journal=Journal of Animal Ecology|volume=77|issue=5|pages=936–47|pmid=18444999|url= http://www.marinebioacoustics.com/files/2008/Soto_et_al_2008.pdf|doi=10.1111/j.1365-2656.2008.01393.x|doi-access=free|bibcode=2008JAnEc..77..936A }}</ref> Compared to [[sperm whale]]s and [[beaked whales]], foraging short-finned pilot whales are more energetic at the same depth. When they reach the end of their dives, pilot whales will sprint, possibly to catch prey, and then make a few buzzes.<ref name="Natacha 2008"/> This is unusual, considering that deep-diving, breath-holding animals would be expected to swim slowly to conserve oxygen. The animal's high metabolism possibly allows it to sprint at deep depths, which would also give it shorter diving periods than some other marine mammals.<ref name="Natacha 2008"/> This may also be the case for long-finned pilot whales.<ref>{{cite journal|author=Heide-Jørgensen M.P., Bloch, D., Stefansson, E., Mikkelsen, B., Ofstad, L. H., Dietz, R. |year=2002|title=Diving behaviour of long-finned pilot whales ''Globicephala melas'' around the Faroe Islands|journal=Wildlife Biology|volume=8|issue=4|pages= 307–13|url=http://www.wildlifebiology.com/Volumes/2002+-+Volume+8/4/386/En/|doi=10.2981/wlb.2002.020|s2cid=131994947|url-access=subscription}}</ref> In 2024, a gps-fitted long-finned pilot whale recorded a diving depth over 1,100 meters.<ref>{{Cite web |last=Mikkelsen |first=Bjarni |date=2024-10-25 |title=Merktur grindahvalur kavar djúpt |trans-title=Tagged pilot whales dive deep |url=https://www.hav.fo/merktur-grindahvalur-kavar-djupt/ |access-date=2024-10-26 |website=Havstovan |language=fo}}</ref> |
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Pilot whales are often infested with [[whale lice]], [[cestodes]], and [[nematodes]].<ref name="Ridgeway 1998"/> They also can be hosts to various pathogenic bacteria and viruses, such as ''[[Streptococcus]]'', ''[[Pseudomonas]]'', ''[[Escherichia]]'', ''[[Staphylococcus]]'', and [[influenza]].<ref name="Ridgeway 1998"/> One sample of Newfoundland pilot whales found the most common illness was an [[upper respiratory tract infection]].<ref>{{cite journal |doi=10.1002/ar.1091550413 |title=Observations on the pilot whale ''Globicephala melaena'': Organweight and growth |year=1966 |last1=Cowan |first1=Daniel F. |journal=The Anatomical Record |volume=155 |issue=4 |pages=623–628}}</ref> |
Pilot whales are often infested with [[whale lice]], [[cestodes]], and [[nematodes]].<ref name="Ridgeway 1998"/> They also can be hosts to various pathogenic bacteria and viruses, such as ''[[Streptococcus]]'', ''[[Pseudomonas]]'', ''[[Escherichia]]'', ''[[Staphylococcus]]'', and [[influenza]].<ref name="Ridgeway 1998"/> One sample of Newfoundland pilot whales found that the most common illness was an [[upper respiratory tract infection]].<ref>{{cite journal |doi=10.1002/ar.1091550413 |title=Observations on the pilot whale ''Globicephala melaena'': Organweight and growth |year=1966 |last1=Cowan |first1=Daniel F. |journal=The Anatomical Record |volume=155 |issue=4 |pages=623–628|s2cid=82948550 }}</ref> |
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===Social structure |
===Social structure=== |
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[[File:LF Pilot Whales Goban Spur.jpg|thumb|left|250px|Pilot whale pod near Ireland]] |
[[File:LF Pilot Whales Goban Spur.jpg|thumb|left|250px|Pilot whale pod near Ireland]] |
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Both species live in groups of 10–30, but some groups may number 100 or more. Data suggest the social structures of pilot whale pods are similar to those of "[[ |
Both species live in groups of 10–30, but some groups may number 100 or more. Data suggest the social structures of pilot whale pods are similar to those of "[[Orca types and populations#North_Pacific|resident]]" killer whales. The pods are highly stable and the members have close [[matrilineal]] relationships.<ref name="Perrin"/> Pod members are of various age and sex classes, although adult females tend to outnumber adult males. They have been observed making various kin-directed behaviors, such as providing food.<ref name="Pryor 1991">Pryor, K., Norris K. S, Marsh, H., Kasuya, T. (1991) "Changes in the role of a female pilot whale with age", pp. 281–86 in ''[https://books.google.com/books?id=yPlKzPGFUvwC Dolphin societies]'', Pryor, K., Norris K. S. (eds), Berkeley, CA: University of California Press.</ref> Numerous pods will temporarily gather, perhaps to allow individuals from different pods to interact and mate,<ref name="Ridgeway 1998"/> as well as provide protection.<ref name="Kasuya1984"/> |
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[[Image:1835 aquaimages.jpg|thumb|right|200px|left|Pilot whale mother and calf near [[Kona District, Hawaii|Kona]], Hawaii]] |
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Both species are loosely [[polygynous]].<ref name="Kasuya1984">{{cite journal|author=Kasuya, T., Marsh, H.|year=1984|url=http://www.helenemarsh.com/publications/JournalPapers/1984/KasuyaMarshLifeReproPilot1984.pdf |title=Life history and reproductive biology of the short-finned pilot whale, ''Globicephala macrorhynchus'', off the Pacific Coast Japan|journal=Rep. Int. Whaling Comm|volume=6 |pages=259–310}}</ref> Data suggest both males and females remain in mother's pod for life; despite this, inbreeding within a pod does not seem to occur.<ref name="Ridgeway 1998"/> During aggregations, males will temporarily leave their pods to mate with females from other pods.<ref name="Amos 1993">{{cite journal |pmid=8480176 |year=1993 |last1=Amos |first1=B |last2=Schlötterer |first2=C |last3=Tautz |first3=D |title=Social structure of pilot whales revealed by analytical DNA profiling |volume=260 |issue=5108 |pages=670–2 |journal=Science |doi=10.1126/science.8480176}}</ref> Male reproductive dominance or competition for mates does not seem to exist.<ref>Donovan, G. P., Lockyer, C. H., Martin, A. R., (1993) "Biology of Northern Hemisphere Pilot Whales", ''International Whaling Commission'' Special Issue 14.</ref> After mating, a male pilot whale usually spends only a few months with a female, and an individual may sire several offspring in the same pod.<ref>{{cite journal |pmid=1917551 |year=1991 |last1=Amos |first1=B |last2=Barrett |first2=J |last3=Dover |first3=GA |title=Breeding behaviour of pilot whales revealed by DNA fingerprinting |volume=67 |issue=1 |pages=49–55 |journal=Heredity |doi=10.1038/hdy.1991.64}}</ref> Males return to their own pods when the aggregations disband, and their presence may contribute to the survival of the other pod members.<ref name="Amos 1993"/> No evidence of "bachelor" groups has been found.<ref name="Kasuya1984"/><ref name="Amos 1993"/> |
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Both species are loosely [[Polygyny in animals|polygynous]].<ref name="Kasuya1984">{{cite journal|last1=Kasuya |first1=T. |last2=Marsh |first2=H. |year=1984|url=http://www.helenemarsh.com/publications/JournalPapers/1984/KasuyaMarshLifeReproPilot1984.pdf|title=Life history and reproductive biology of the short-finned pilot whale, ''Globicephala macrorhynchus'', off the Pacific Coast Japan|journal=Rep. Int. Whal. Comm.|volume=6|pages=259–310|access-date=15 May 2011|archive-date=19 May 2017|archive-url=https://web.archive.org/web/20170519005832/http://www.helenemarsh.com/publications/JournalPapers/1984/KasuyaMarshLifeReproPilot1984.pdf|url-status=dead}}</ref> Data suggest both males and females remain in their mother's pod for life; despite this, inbreeding within a pod does not seem to occur.<ref name="Ridgeway 1998"/> During aggregations, males will temporarily leave their pods to mate with females from other pods.<ref name="Amos 1993">{{cite journal |pmid=8480176 |year=1993 |last1=Amos |first1=B |last2=Schlötterer |first2=C |last3=Tautz |first3=D |title=Social structure of pilot whales revealed by analytical DNA profiling |volume=260 |issue=5108 |pages=670–2 |journal=Science |doi=10.1126/science.8480176|bibcode=1993Sci...260..670A }}</ref> Male reproductive dominance or competition for mates does not seem to exist.<ref>Donovan, G. P., Lockyer, C. H., Martin, A. R., (1993) "Biology of Northern Hemisphere Pilot Whales", ''International Whaling Commission'' Special Issue 14. {{ISBN|9780906975275}}</ref> After mating, a male pilot whale usually spends only a few months with a female, and an individual may sire several offspring in the same pod.<ref>{{cite journal |pmid=1917551 |year=1991 |last1=Amos |first1=B |last2=Barrett |first2=J |last3=Dover |first3=GA |title=Breeding behaviour of pilot whales revealed by DNA fingerprinting |volume=67 |issue=1 |pages=49–55 |journal=Heredity |doi=10.1038/hdy.1991.64|doi-access=free }}</ref> Males return to their own pods when the aggregations disband, and their presence may contribute to the survival of the other pod members.<ref name="Amos 1993"/> No evidence of "bachelor" groups has been found.<ref name="Kasuya1984"/><ref name="Amos 1993"/> |
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Pilot whale pods off southern California have been observed in three different groups: traveling/hunting groups, feeding groups and loafing groups.<ref name="Norris 1961">{{cite journal|author=Norris, K. S., Prescott, J. H.|year=1961|title=Observations on Pacific cetaceans of Californian and Mexican waters|journal=University of California Publications in Zoology|volume=63|pages= 291–402|url=http://openlibrary.org/books/OL5870789M/Observations_on_Pacific_cetaceans_of_Californian_and_Mexican_waters}}</ref> In traveling/hunting groups, individuals position themselves in chorus lines stretching two miles long, with only a few whales underneath.<ref>Leatherwood, S., Lingle, G. E., Evans, W. E., (1973) "The Pacific pilot whale, ''Globicephala'' spp". ''Naval Undersea Center Technical Note'' 933.</ref> Sexual and age-class segregation apparently occurs in these groups.<ref name="Norris 1961"/> In feeding groups, individuals are very loosely associated, but may move in the same direction.<ref name="Norris 1961"/> In loafing groups, whales number between 12 and 30 individuals resting. Mating and other behavior may take place.<ref name="Norris 1961"/> |
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[[Image:1835 aquaimages.jpg|thumb|upright|Pilot whale mother and calf near [[Kona District, Hawaii|Kona]], Hawaii]] |
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Pilot whale pods off southern California have been observed in three different groups: traveling/hunting groups, feeding groups and loafing groups.<ref name="Norris 1961">{{cite journal |last1=Norris |first1=K. S. |last2=Prescott |first2=J. H.|year=1961|title=Observations on Pacific cetaceans of Californian and Mexican waters|journal=University of California Publications in Zoology|volume=63|pages= 291–402|ol=5870789M}}</ref> In traveling/hunting groups, individuals position themselves in chorus lines stretching two miles long, with only a few whales underneath.<ref>Leatherwood, S., Lingle, G. E., Evans, W. E., (1973) "The Pacific pilot whale, ''Globicephala'' spp". ''Naval Undersea Center Technical Note'' 933.</ref> Sexual and age-class segregation apparently occurs in these groups.<ref name="Norris 1961"/> In feeding groups, individuals are very loosely associated, but may move in the same direction.<ref name="Norris 1961"/> In loafing groups, whales number between 12 and 30 individuals resting. Mating and other behaviors may take place.<ref name="Norris 1961"/> |
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===Reproduction and lifecycle=== |
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Pilot whales have one of the longest birth intervals of the cetaceans,<ref name="Perrin"/> calving once every three to five years. Most matings and calvings occur during the summer for long-finned pilot whales.<ref name="Jefferson 1993">Jefferson T. A., Leatherwood, S., Webber, M. A. (1993) "FAO Species identification guide. Marine mammals of the world". ''UNEP/FAO'', Rome. [ftp://ftp.fao.org/docrep/fao/009/t0725e/t0725e00.pdf Preview]</ref> For short-finned pilot whales of the Southern Hemisphere, births are at their highest in spring and autumn, while in Northern Hemisphere, the time in which calving peaks can vary by population.<ref name="Jefferson 1993"/> For long-finned pilot whales, gestation lasts 12–16 months, and short-finned pilot whales have a 15-month gestation period.<ref name="Perrin"/> The calf nurses for three years, although lactation usually lasts longer, allowing for extensive mother-calf bonds.<ref name="Perrin"/> Short-finned pilot whale females will go though [[menopause]],<ref>Marsh, H., Kasuya T. (1984). "[http://geckodesign.biz/dugong/publications/JournalPapers/1984/Marsh%20and%20Kasuya%201984.%20IWC%20Spec.%20Iss.%206..pdf Ovarian changes in the short-finned pilot whale, ''Globicephala macrorhynchus'']" ''Rep. Int. Whaling Comm'' 6: 311–35. Special Issue.</ref> but this is not as common in females of long-finned pilot whales.<ref>Martin A.R, Rothery P. (1993). "Reproductive parameters of female long-finned pilot whales (''Globicephala melas'') around the Faroe Islands" ''Rep. Int. Whaling Comm'' 14 263–304. Special Issue.</ref> Postreproductive females possibly play important roles in the survival of the young.<ref name="Pryor 1991"/><ref>{{cite journal|author=Foote, A. D.|year=2008|title=Mortality rate acceleration and post-reproductive lifespan in matrilineal whale species|journal=Biol. Lett|volume=4|issue=2|pages=189–91|doi= 10.1098/rsbl.2008.0006|url=http://rsbl.royalsocietypublishing.org/content/4/2/189.full|pmid=18252662|pmc=2429943}}</ref> Postreproductive females will continue to lactate and nurse young. Since they can no longer bear young of their own, these females invest in the current young.<ref name="Perrin"/> Short-finned pilot whales grow more slowly than long-finned pilot whales. For the short-finned pilot whale, females become sexually mature at 9 years old and males at about 13–16 years.<ref name="Perrin"/> For the long-finned pilot whale, females reach maturity at around eight years and males at around 12 years.<ref name="Perrin"/> |
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Pilot whales have one of the longest birth intervals of the cetaceans,<ref name="Perrin"/> calving once every three to five years. Most matings and calvings occur during the summer for long-finned pilot whales.<ref name="Jefferson 1993">Jefferson T. A., Leatherwood, S., Webber, M. A. (1993) "FAO Species identification guide. Marine mammals of the world". ''UNEP/FAO'', Rome. [ftp://ftp.fao.org/docrep/fao/009/t0725e/t0725e00.pdf Preview] {{Webarchive|url=https://wayback.archive-it.org/all/20130302192659/ftp://ftp.fao.org/docrep/fao/009/t0725e/t0725e00.pdf |date=2 March 2013 }}</ref> For short-finned pilot whales of the Southern Hemisphere, births are at their highest in spring and autumn, while in Northern Hemisphere, the time in which calving peaks can vary by population.<ref name="Jefferson 1993"/> For long-finned pilot whales, gestation lasts 12–16 months, and short-finned pilot whales have a 15-month gestation period.<ref name="Perrin"/> |
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The calf nurses for 36–42 months, allowing for extensive mother-calf bonds.<ref name="Perrin"/> Young pilot whales will take milk until as old as 13–15 years of age. Short-finned pilot whale females will go through [[menopause]],<ref>Marsh, H., Kasuya T. (1984). "[http://geckodesign.biz/dugong/publications/JournalPapers/1984/Marsh%20and%20Kasuya%201984.%20IWC%20Spec.%20Iss.%206..pdf Ovarian changes in the short-finned pilot whale, ''Globicephala macrorhynchus''] {{webarchive|url=https://web.archive.org/web/20110817023636/http://geckodesign.biz/dugong/publications/JournalPapers/1984/Marsh%20and%20Kasuya%201984.%20IWC%20Spec.%20Iss.%206..pdf |date=17 August 2011 }}" ''Rep. Int. Whal. Comm.'' 6: 311–35. Special Issue.</ref> but this is not as common in females of long-finned pilot whales.<ref>Martin A.R, Rothery P. (1993). "Reproductive parameters of female long-finned pilot whales (''Globicephala melas'') around the Faroe Islands" ''Rep. Int. Whal. Comm.'' 14 263–304. Special Issue.</ref> Postreproductive females possibly play important roles in the survival of the young.<ref name="Pryor 1991"/><ref>{{cite journal|author=Foote, A. D.|year=2008|title=Mortality rate acceleration and post-reproductive lifespan in matrilineal whale species|journal=Biol. Lett.|volume=4|issue=2|pages=189–91|doi= 10.1098/rsbl.2008.0006|pmid=18252662|pmc=2429943}}</ref> Postreproductive females will continue to lactate and nurse young. Since they can no longer bear young of their own, these females invest in the current young, allowing them to feed even though they are not their own.<ref name="Perrin"/> Short-finned pilot whales grow more slowly than long-finned pilot whales. For the short-finned pilot whale, females become sexually mature at 9 years old and males at about 13–16 years.<ref name="Perrin"/> For the long-finned pilot whale, females reach maturity at around eight years and males at around 12 years.<ref name="Perrin"/> |
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===Vocalizations=== |
===Vocalizations=== |
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Pilot whales |
Pilot whales emit echolocation clicks for foraging and whistles and burst pulses as social signals (e.g. to keep contact with members of their pod). With active behavior, vocalizations are more complex, while less-active behavior is accompanied by simple vocalizations. Differences have been found in the calls of the two species.<ref name="Rendell 1999">{{cite journal |doi=10.1111/j.1469-7998.1999.tb01209.x |title=Quantitative analysis of tonal calls from five odontocete species, examining interspecific and intraspecific variation |year=1999 |last1=Rendell |first1=L. E. |last2=Matthews |first2=J. N. |last3=Gill |first3=A. |last4=Gordon |first4=J. C. D. |last5=MacDonald |first5=D. W. |journal=Journal of Zoology |volume=249 |issue=4 |pages=403–410}}</ref> Compared with short-finned pilot whales, long-finned pilot whales have relatively low-frequency calls with narrow frequency ranges.<ref name="Rendell 1999"/> In one study of North Atlantic long-finned pilot whales, certain vocalizations were heard to accompany certain behaviors.<ref name="Whitehead 2002">{{cite journal |doi=10.1007/BF00170896 |title=Vocalizations of the North Atlantic pilot whale (''Globicephala melas'') as related to behavioral contexts |year=1990 |last1=Weilgart |first1=Lindas. |last2=Whitehead |first2=Hal |journal=Behavioral Ecology and Sociobiology |volume=26 |issue=6|page=399 |bibcode=1990BEcoS..26..399W |s2cid=34187605 }}</ref> When resting or "milling", simple whistles are emitted.<ref name="Whitehead 2002"/> Surfacing behavior is accompanied by more complex whistles and pulsed sounds.<ref name="Whitehead 2002"/> The number of whistles made increases with the number of subgroups and the distance in which the whales are spread apart.<ref name="Whitehead 2002"/> |
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[[Image:Whales on beach, Farewell Split, South Island, New Zealand.JPG|thumb|left|Volunteers attempt to keep body temperatures of beached pilot whales from rising at [[Farewell Spit]], [[New Zealand]].]] |
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A study of short-finned pilot whales off the southwest coast of [[Tenerife]] in the [[Canary Islands]] has found the members of a pod maintained contact with each other through call repertoires unique to their pod.<ref>Scheer, M., Hofmann, B., Behr, I.P. (1998) [http://www.pilot-whales.org/www/en/pdf/pilot_whales_culture.pdf "Discrete pod-specific call repertoires among short-finned pilot whales (Globicephala macrorhynchus) off the SW coast of Tenerife, Canary Islands"]. ''Abstract World Marine Mammal Science Conference'', 20–24. January, Monaco by European Cetacean Society and Society for Marine Mammalogy.</ref> A later study found, when foraging at around 800 m deep, short-finned pilot whales make tonal calls.<ref name="Jensen 2011">{{cite journal |doi=10.1098/rspb.2010.2604 |title=Calling under pressure: short-finned pilot whales make social calls during deep foraging dives |year=2011 |last1=Jensen |first1=F. H. |last2=Perez |first2=J. M. |last3=Johnson |first3=M. |last4=Soto |first4=N. A. |last5=Madsen |first5=P. T. |journal=Proceedings of the Royal Society B: Biological Sciences |volume=278 |issue=1721 |pages= |
A study of short-finned pilot whales off the southwest coast of [[Tenerife]] in the [[Canary Islands]] has found the members of a pod maintained contact with each other through call repertoires unique to their pod.<ref>Scheer, M., Hofmann, B., Behr, I.P. (1998) [http://www.pilot-whales.org/www/en/pdf/pilot_whales_culture.pdf "Discrete pod-specific call repertoires among short-finned pilot whales (Globicephala macrorhynchus) off the SW coast of Tenerife, Canary Islands"]. ''Abstract World Marine Mammal Science Conference'', 20–24. January, Monaco by European Cetacean Society and Society for Marine Mammalogy.</ref> A later study found, when foraging at around 800 m deep, short-finned pilot whales make tonal calls.<ref name="Jensen 2011">{{cite journal |doi=10.1098/rspb.2010.2604 |title=Calling under pressure: short-finned pilot whales make social calls during deep foraging dives |year=2011 |last1=Jensen |first1=F. H. |last2=Perez |first2=J. M. |last3=Johnson |first3=M. |last4=Soto |first4=N. A. |last5=Madsen |first5=P. T. |journal=Proceedings of the Royal Society B: Biological Sciences |volume=278 |issue=1721 |pages=3017–3025 |pmid=21345867 |pmc=3158928}}</ref> The number and length of the calls seem to decrease with depth despite being farther away from [[Conspecificity|conspecifics]] at the surface. As such, the surrounding water pressure affects the energy of the calls, but it does not appear to affect the frequency levels.<ref name="Jensen 2011"/> |
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When in stressful situations, pilot whales produce "shrills" or "plaintive cries", which are variations of their whistles.<ref>{{cite journal|author=Alagarswami, K., Bensam, P., Rajapandian, M. E., Fernando, A. B. |year=1973|url=https://agris.fao.org/agris-search/search.do?recordID=IN2022009506|title=Mass stranding of Pilot whales in the Gulf of Mannar|journal=Indian J. Fish|volume=20 |issue=2|pages=269–279}}</ref> To elude predators, long-finned pilot whales off the southern coast of Australia have been observed to mimic the calls of orcas while scavenging for food. This behaviour is thought to deter orca pods from approaching the pilot whales.<ref>{{cite news |last1=Leckie |first1=Evelyn |title=Pilot whales recorded along Great Australian Bight found to be mimicking predators' calls. |url=https://www.abc.net.au/news/2020-12-14/pilot-whales-on-great-australian-bight-mimicking-predators/12981626 |website=ABC News |date=14 December 2020 |access-date=15 December 2020}}</ref> |
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===Antagonistic interactions with other species=== |
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Pilot whales have been occasionally observed mobbing or chasing other species of cetaceans. In several parts of the world, including off Iceland, long-finned pilot whales have been frequently documented chasing killer whales.<ref>{{cite journal |author1=Selbmann A. |author2=Basran C.J. |author3=Bertulli C.G. |author4=Hudson T. |author5=Mrusczok M.|author6=Rasmussen M.H.|author7=Rempel J.N.|author8=Scott J. |author9=Svavarsson J. |author10=Weensveen, P.J |author11= Whittaker M. | year = 2022 | title = Occurrence of long-finned pilot whales (Globicephala melas) and killer whales (Orcinus orca) in Icelandic coastal waters and their interspecific interactions | journal = Acta Ethologica | volume = 25 | issue = 3 | pages = 141–154| doi=10.1139/z03-127|pmid=35694552 |pmc=9170559 |s2cid=56260446 }}</ref> The reasons for these chases are unknown, but it has been proposed that they might be due to either competition for prey or an anti-predation strategy. In 2021 an adult female killer whale with a newborn pilot whale travelling alongside her was observed off Western Iceland, leading scientists to question whether the relationship between these species might be far more complex than previously suggested.<ref>{{cite journal |author1=Mrusczok M. |author2=Zwamborn E. |author3=von Schmalensee M.|author4= Rodriguez Ramallo S. |author5=Stefansson R. A. | year = 2023 | title = First account of apparent alloparental care of a long-finned pilot whale calf (Globicephala melas) by a female killer whale (Orcinus orca) | journal = Canadian Journal of Zoology |volume=101 |issue=4 |pages=288–293 | doi=10.1139/cjz-2022-0161 |s2cid=257010608 |doi-access=free |bibcode=2023CaJZ..101..288M }}</ref> It is not known whether the newborn was adopted or abducted, but this same female killer whale was seen a year later interacting with a larger group of pilot whales. |
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Based on experimentation involving familiar sounds of Orcas that consume fish and unfamiliar vocalizations of mammal-hunting Killer Whales, one study suggests that long-finned pilot whales can distinguish between familiar and unaccustomed types of Orca, noting behavioral differences like the ceasing of feeding when mammal-hunting Orcas' sounds were played. The study suggests that antagonistic interactions against fish-eating Killer Whales could either be an anti-predatory behavior or an attempt to maintain territory, while actions done in response to mammal-hunting Killer Whales could be a response to a more dangerous threat. <ref>{{cite journal |last= Cure |first= Charlotte |year= 2019 |title= Evidence for discrimination between feeding sounds of familiar fish and unfamiliar mammal-eating killer whale ecotypes by long-finned pilot whales |journal= Anim Cogn |issue= 22 |page= 863-882 |doi= 10.1007/s10071-019-01282-1}}</ref> |
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When in stressful situations, pilot whales produce "shrills" or "plaintive cries", which are variations of their whistles.<ref>{{cite journal|author=Alagarswami, K., Bensam, P., Rajapandian, M. E., Fernando, A. B. |year=1973|title=Mass stranding of Pilot whales in the Gulf of Mannar|journal=Indian J. Fish|volume=20 |issue=2|pages=269–279}}</ref> |
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===Stranding=== |
===Stranding=== |
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[[Image:Whales on beach, Farewell Split, South Island, New Zealand.JPG|thumb|left|Volunteers attempt to keep body temperatures of beached pilot whales from rising at [[Farewell Spit]], [[New Zealand]].]] |
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Of the cetaceans, pilot whales are among the most common [[beached whale|strander]]s. Because of their strong social bonds, whole groups of pilot whales will strand. Single stranders have been recorded and these are usually diseased.<ref name="Perrin"/> Group stranding tends to be of mostly healthy individuals. Several hypotheses have been proposed to explain group strandings.<ref name="Perrin"/> When using magnetic fields for navigation, the whales have been suggested to get perplexed by geomagnetic anomalies or they may be following a sick member of their group that got stranded.<ref name="Perrin"/> The pod also may be following a member of high importance that got stranded and a secondary social response makes them keep returning.<ref name="Ridgeway 1998">Ridgway, S. H. (1998). ''[http://books.google.com/books?id=At4jWmmaq6QC&printsec=frontcover Handbook of Marine Mammals: The second book of dolphins and the porpoises, Volume 6]'', Elsevier. pp. 245–69. ISBN 0-12-588506-7</ref> Researchers from New Zealand have successfully used secondary social responses to keep a stranding pod of long-finned pilot whales from returning to the beach.<ref name="Dawson 1985">{{cite journal|author=Dawson, S. M., S. Whitehouse, M. Williscroft|year=1985|title=A mass stranding of pilot whales in Tryphena Harbour, Great Barrier Island|journal=Invest. Cetacea|volume=17|pages=165–73}}</ref> In addition, the young members of the pod were taken offshore to buoys, and their distress calls lured the older whales back out to sea.<ref name="Dawson 1985"/> |
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Of the cetaceans, pilot whales are among the most common [[beached whale|strander]]s.<ref>{{Cite web|title=Pilot whale|url=https://iwc.int/pilot-whale|access-date=2020-08-07|website=iwc.int|language=en}}</ref> Because of their strong social bonds, whole groups of pilot whales will strand. Single stranders have been recorded and these are usually diseased.<ref name="Perrin"/> Group stranding tends to be of mostly healthy individuals. Several hypotheses have been proposed to explain group strandings.<ref name="Perrin"/> When using magnetic fields for navigation, the whales have been suggested to get perplexed by geomagnetic anomalies or they may be following a sick member of their group that got stranded.<ref name="Perrin"/> The pod also may be following a member of high importance that got stranded and a secondary social response makes them keep returning.<ref name="Ridgeway 1998">Ridgway, S. H. (1998). ''[https://books.google.com/books?id=At4jWmmaq6QC Handbook of Marine Mammals: The second book of dolphins and the porpoises, Volume 6]'', Elsevier. pp. 245–69. {{ISBN|0-12-588506-7}}</ref> Researchers from New Zealand have successfully used secondary social responses to keep a stranding pod of long-finned pilot whales from returning to the beach.<ref name="Dawson 1985">{{cite journal |last1=Dawson |first1=S. M. |first2=S. |last2=Whitehouse |first3=M. |last3=Williscroft |year=1985 |title=A mass stranding of pilot whales in Tryphena Harbour, Great Barrier Island |
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|journal=Invest. Cetacea|volume=17|pages=165–73}}</ref> In addition, the young members of the pod were taken offshore to buoys, and their distress calls lured the older whales back out to sea.<ref name="Dawson 1985"/> |
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In September 2022, nearly 200 pilot whales died after becoming stranded on Ocean Beach, part of Tasmania's west coast. Authorities said only about 35 survived of the 230 that were stranded.<ref>{{Cite web |date=2022-09-22 |title=Nearly 200 stranded pilot whales die on Tasmanian beach but dozens saved and returned to sea |url=https://www.theguardian.com/australia-news/2022/sep/22/nearly-200-stranded-pilot-whales-die-on-tasmanian-beach |access-date=2022-09-23 |website=the Guardian |language=en}}</ref> |
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==Human interaction== |
==Human interaction== |
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The [[IUCN]] lists |
The [[IUCN]] lists long-finned pilot whales as "least concern" in the [[Red List of Threatened Species]]. Long-finned pilot whales in the North and Baltic Seas are listed in Appendix II of the [[Convention on the Conservation of Migratory Species of Wild Animals]] (CMS). Those from northwest and northeast Atlantic may also need to be included to Appendix II of CMS.<ref name=icun/> The short-finned pilot whale is listed on Appendix II of [[CITES]].<ref name=icun2/> |
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===Hunting=== |
===Hunting=== |
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[[File:Killed pilot wales in hvalba, faroe islands.JPG|thumb|250px|left|Killed pilot whales in [[Hvalba]], Faroe Islands]] |
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{{See also|Whaling in the Faroe Islands}} |
{{See also|Whaling in the Faroe Islands}} |
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[[File:Killed pilot wales in hvalba, faroe islands.JPG|thumb|250px|left|Killed pilot whales in [[Hvalba]], Faroe Islands]] |
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The long-finned pilot whale has traditionally been hunted by "[[Dolphin drive hunting|driving]]", which involves many hunters and boats gathering in a semicircle behind a pod of whales close to shore, and slowly driving them towards a bay, where they become stranded and are then slaughtered. This practice was common in both the 19th and 20th centuries. At the [[Faroe Islands]], pilot whale hunting started at least in the 16th century,<ref name="Ridgeway 1998"/> and continued into the modern times, as thousands were killed during the 1970s and '80s.<ref name="Mitchell 1975">{{cite journal|author=Mitchell, E. D. |year=1975|title=Porpoise, dolphin, and small whale fisheries of the world: status and problems|journal=International Union for Conservation of Nature and Natural Resources|volume= 3|pages=1–129}}</ref><ref>{{cite journal|author=Hoydal, K. |year=1987|title=Data on the long-finned pilot whale (''Globicephala melaena'' Traill), in Faroe waters and an attempt to use the 274 years time series of catches to assess the state of the stock|journal=Rep. Int. Whaling Comm|volume=37|pages=1–27}}</ref> In other parts of the North Atlantic, such as [[Norway]], West Greenland, Ireland and [[Cape Cod]], pilot whales have also been hunted, but to a lesser extent.<ref>{{cite journal|author=Kapel, F.O.|year=1975|title=Preliminary notes on the occurrence and exploitation of smaller Cetacea in Greenland|journal= Fish Res Board Can|volume=32|issue=7|pages=1079–82|doi=10.1139/f75-128}}</ref> Iceland,.<ref>{{cite journal|author=O'Riordan, C. E.|year=1975|title=Long-finned pilot whales, ''Globicephala'', driven ashore in Ireland, 1800–1973|journal= Fish Res Board Can|volume=32|issue=7|pages=1101–03|doi=10.1139/f75-131}}</ref> One fishery at Cape Cod harvested 2,000–3,000 whales per year during the late 19th and early 20th centuries.<ref>{{cite journal|author=Mitchell, E. D. |year=1975|title=Report of the meeting on smaller cetaceans, Montreal, 1–11 April 1974|journal=J Fish Res Board Can|volume=32|pages=889–983|doi=10.1139/f75-117|issue=7}}</ref> [[Newfoundland (island)|Newfoundland]]'s long-finned pilot whale fishery was at its highest in 1956, but declined shortly after<ref name="Mitchell 1975"/> and is now defunct. In the Southern Hemisphere, exploitation of long-finned pilot whales has been sporadic and low.<ref name="Mitchell 1975"/> Currently, long-finned pilot whales are only hunted at the Faroe Islands and Greenland.<ref name=icun>Taylor, B. L., Baird, R., Barlow, J., Dawson, S. M., Ford, J., Mead, J.G., Notarbartolo di Sciara, G., Wade, P. & Pitman, R.L. (2008) [http://www.iucnredlist.org/apps/redlist/details/9250/0 ''Globicephala melas'']. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.1.</ref> |
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The long-finned pilot whale has traditionally been hunted by "[[Dolphin drive hunting|driving]]", which involves many hunters and boats gathering in a semicircle behind a pod of whales close to shore, and slowly driving them towards a bay, where they become stranded and are then slaughtered. This practice was common in both the 19th and 20th centuries. The whales were hunted for bone, meat, oil, and fertilizer. In the [[Faroe Islands]], pilot whale hunting started at least in the 16th century,<ref name="Ridgeway 1998"/> and continued into modern times, with thousands being killed during the 1970s and 1980s.<ref name="Mitchell 1975">{{cite journal|author=Mitchell, E. D. |year=1975|title=Porpoise, dolphin, and small whale fisheries of the world: status and problems|journal=International Union for Conservation of Nature and Natural Resources|volume= 3|pages=1–129}}</ref><ref>{{cite journal|author=Hoydal, K. |year=1987|title=Data on the long-finned pilot whale (''Globicephala melaena'' Traill), in Faroe waters and an attempt to use the 274 years time series of catches to assess the state of the stock|journal=Rep. Int. Whal. Comm.|volume=37|pages=1–27}}</ref> In other parts of the North Atlantic, such as [[Norway]], West Greenland, Ireland and [[Cape Cod]], pilot whales have also been hunted, but to a lesser extent.<ref>{{cite journal|author=Kapel, F.O.|year=1975|title=Preliminary notes on the occurrence and exploitation of smaller Cetacea in Greenland|journal=J. Fish. Res. Board Can.|volume=32|issue=7|pages=1079–82|doi=10.1139/f75-128}}</ref><ref>{{cite journal|author=O'Riordan, C. E.|year=1975|title=Long-finned pilot whales, ''Globicephala'', driven ashore in Ireland, 1800–1973|journal=J. Fish. Res. Board Can.|volume=32|issue=7|pages=1101–03|doi=10.1139/f75-131}}</ref> One fishery at Cape Cod harvested 2,000–3,000 whales per year during the late 19th and early 20th centuries.<ref>{{cite journal|author=Mitchell, E. D. |year=1975|title=Report of the meeting on smaller cetaceans, Montreal, 1–11 April 1974|journal=J. Fish. Res. Board Can.|volume=32|pages=889–983|doi=10.1139/f75-117|issue=7}}</ref> [[Newfoundland (island)|Newfoundland]]'s long-finned pilot whale fishery was at its highest in 1956, but declined shortly after<ref name="Mitchell 1975"/> and is now defunct. In the Southern Hemisphere, exploitation of long-finned pilot whales has been sporadic and low.<ref name="Mitchell 1975"/> Currently, long-finned pilot whales are only hunted at the Faroe Islands and Greenland.<ref name=icun>{{cite iucn |author=Minton, G. |author2=Reeves, R. |author3=Braulik, G. |date=2018 |title=''Globicephala melas'' |volume=2018 |page=e.T9250A50356171 |doi=10.2305/IUCN.UK.2018-2.RLTS.T9250A50356171.en |access-date=18 November 2021}}</ref> |
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According to the IUCN the harvesting of this species for food in the Faroe Islands and Greenland has not resulted in any detectable declines in abundance.<ref>{{Cite iucn|url=https://www.iucnredlist.org/species/9250/50356171|title=The IUCN Red List of Threatened Species|access-date=2020-06-21}}</ref> |
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The short-finned pilot whale has also been hunted for many centuries, particularly by [[Whaling in Japan|Japanese whalers]]. Between 1948 and 1980, hundreds of whales were exploited at [[Hokkaido]] and [[Sanriku]] in the north and [[Taiji, Wakayama|Taiji]], [[Izu, Shizuoka|Izu]], and [[Okinawa]] in the south.<ref name="Kasuya1984"/> These fisheries were at their highest in the late 1940s and early 1950s;<ref name="Kasuya1984"/> 2,326 short-finned pilot whales were harvested in the mid- to late 1980s.<ref name=icun2>Taylor, B. L., Baird, R., Barlow, J., Dawson, S. M., Ford, J., Mead, J. G., Notarbartolo di Sciara, G., Wade, P. & Pitman, R.L. (2008) [http://www.iucnredlist.org/apps/redlist/details/9249/0 ''Globicephala macrorhynchus'']. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.1.</ref> This had decreased to about 400 per year by the 1990s. |
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The short-finned pilot whale has also been hunted for many centuries, particularly by [[Whaling in Japan|Japanese whalers]]. Between 1948 and 1980, hundreds of whales were exploited at [[Hokkaido]] and [[Sanriku]] in the north and [[Taiji, Wakayama|Taiji]], [[Izu, Shizuoka|Izu]], and [[Okinawa Prefecture|Okinawa]] in the south.<ref name="Kasuya1984"/> These fisheries were at their highest in the late 1940s and early 1950s;<ref name="Kasuya1984"/> 2,326 short-finned pilot whales were harvested in the mid- to late 1980s.<ref name=icun2>{{cite iucn |author=Minton, G. |author2=Braulik, G. |author3=Reeves, R. |date=2018 |title=''Globicephala macrorhynchus'' |volume=2018 |page=e.T9249A50355227 |doi=10.2305/IUCN.UK.2018-2.RLTS.T9249A50355227.en |access-date=18 November 2021}}</ref> This had decreased to about 400 per year by the 1990s. |
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Pilot whales have also fallen victim to [[Cetacean bycatch|bycatches]]. In one year, around 30 short-finned pilot whales were caught by the squid round-haul fishery in southern California.<ref>Miller, D. J., Herder, M. J., Scholl, J. P. (1983) "California marine mammal- fishery interaction study. 1979–81", ''NMFS Southwest Fish. Cent., Admin. Rep''. No. LJ-83-13C, 233 pp.</ref> Likewise, California's drift gill net fishery took around 20 whales a year in the mid-1990s.<ref name="Ridgeway 1998"/> In 1988, 141 whales caught on the east coast of the US were taken by the foreign Atlantic [[mackerel]] fishery, which forced it to be shut down.<ref name="Ridgeway 1998"/> |
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[[Image:Tvost og spik.jpg|thumb|200px|right|Pilot whale [[whale meat|meat]] (black), blubber (middle), dried fish (left) and potatoes, a meal on the Faroe Islands]] |
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Pilot whales have also fallen victim to [[Cetacean bycatch|bycatches]]. In one year, around 30 short-finned pilot whales were caught by the squid round-haul fishery in southern California.<ref>Miller, D. J., Herder, M. J., Scholl, J. P. (1983) [https://repository.library.noaa.gov/view/noaa/26652 "California marine mammal- fishery interaction study. 1979–81"], ''NMFS Southwest Fish. Cent., Admin. Rep''. No. LJ-83-13C</ref> Likewise, California's drift gill net fishery took around 20 whales a year in the mid-1990s.<ref name="Ridgeway 1998"/> In 1988, 141 whales caught on the east coast of the U.S. were taken by the foreign Atlantic [[mackerel]] fishery, which forced it to be shut down.<ref name="Ridgeway 1998"/> |
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[[File:6208-MarineLandPilotWhaleShow-Bubbles-1.jpg|thumb|300px|Bubbles the pilot whale performing at [[Marineland of the Pacific]], 1962]] |
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===Pollution=== |
===Pollution=== |
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As with other marine mammals, pilot whales are susceptible to certain pollutants. Off the Faroes, France, the UK, and the eastern US, pilot whales were found to have been contaminated with high amounts of [[DDT]] and [[Polychlorinated biphenyl|PCB]].<ref name="Ridgeway 1998"/> The Faroes whales have also been contaminated with [[cadmium]] and [[Mercury (element)|mercury]].<ref>{{cite journal |pmid=8029711 |year=1994 |last1=Simmonds |first1=MP |last2=Johnston |first2=PA |last3=French |first3=MC |last4=Reeve |first4=R |last5=Hutchinson |first5=JD |title=Organochlorines and mercury in pilot whale blubber consumed by Faroe islanders |volume=149 |issue=1–2 |pages=97–111 |journal=The Science of the |
As with other marine mammals, pilot whales are susceptible to certain pollutants. Off the Faroes, France, the UK, and the eastern US, pilot whales were found to have been contaminated with high amounts of [[DDT]] and [[Polychlorinated biphenyl|PCB]].<ref name="Ridgeway 1998"/> Pollutants such as DDT and mercury can be passed from mothers to their babies during gestation and lactation.<ref>{{cite journal |last1=Dam |first1=Maria |last2=Bloch |first2=Dorete |title=Screening of Mercury and Persistent Organochlorine Pollutants in Long-Finned Pilot Whale (''Globicephala melas'') in the Faroe Islands |journal= Marine Pollution Bulletin|date=December 2000 |volume=40 |issue=12 |pages=1090–1099 |doi=10.1016/S0025-326X(00)00060-6|bibcode=2000MarPB..40.1090D }}</ref> The Faroes whales have also been contaminated with [[cadmium]] and [[Mercury (element)|mercury]].<ref>{{cite journal |pmid=8029711 |year=1994 |last1=Simmonds |first1=MP |last2=Johnston |first2=PA |last3=French |first3=MC |last4=Reeve |first4=R |last5=Hutchinson |first5=JD |title=Organochlorines and mercury in pilot whale blubber consumed by Faroe islanders |volume=149 |issue=1–2 |pages=97–111 |journal=The Science of the Total Environment |doi=10.1016/0048-9697(94)90008-6|bibcode=1994ScTEn.149...97S }}</ref> However, pilot whales from [[Newfoundland (island)|Newfoundland]] and [[Tasmania]] were found to have had very low levels of DDT.<ref name="Ridgeway 1998"/> Short-finned pilot whales off the west coast of the US have had high amounts of DDT and PCB in contrast to the low amounts found in whales from Japan and the Antilles.<ref name="Ridgeway 1998"/> |
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===Cuisine=== |
===Cuisine=== |
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[[Image:Tvost og spik.jpg|thumb|left|upright|Pilot [[whale meat]] (black), blubber (middle), dried fish (left) and potatoes (top), a meal on the Faroe Islands]] |
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Pilot whale [[whale meat|meat]] is available for consumption in very few areas of [[Japan]], mainly along the central Pacific coast, and also in other areas of the world, such as the Faroe Islands. The meat is high in [[protein]] (higher than beef) and low in fat.<ref name=browne>{{cite news|last=Browne|first=Anthony |title= Stop Blubbering: Whales are supposed to be protected but that doesn't stop the Japanese killing and eating hundreds of them every year. But does the West's moral outrage over the pursuit of our gentle leviathans amount to anything more than hypocrisy and cultural bullying? |periodical= The Observer|date= 9 September 2001 |url= http://www.guardian.co.uk/lifeandstyle/2001/sep/09/foodanddrink.features4 |accessdate=14 June 2011}}</ref> Because a whale's fat is contained in the layer of [[blubber]] beneath the skin, and the muscle is high in myoglobin, the meat is a dark shade of red.<ref name=browne/><ref name=ark/> In Japan, where pilot whale meat can be found in certain restaurants and ''[[izakaya]]s'', the meat is sometimes served raw, as ''[[sashimi]]'', but just as often pilot whale steaks are marinated, cut into small chunks, and grilled.<ref name=ark/> When grilled, the meat is slightly flaky and quite flavorful, gamey, though similar to a quality cut of [[beef]], with distinct yet subtle undertones recalling its marine origin.<ref name=browne/><ref name=ark>{{cite journal|title= No matter how you slice it, whale tastes unique |year=2002| journal=Planet Ark |url= http://www.planetark.org/dailynewsstory.cfm/newsid/16090/story.htm |publisher=Reuters |accessdate=14 January 2011}}</ref><ref name=buncombe>{{cite journal |last= Buncombe| first= Andrew| title=The Whaling Debate: Arctic Lament |year=2005 |journal= Ezilon |url= http://www.ezilon.com/information/article_11436.shtml |accessdate=14 January 2011}}</ref> |
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Pilot [[whale meat]] is available for consumption in very few areas of [[Japan]], mainly along the central Pacific coast, and also in other areas of the world, such as the Faroe Islands. The meat is high in [[protein]] (higher than beef) and low in fat.<ref name=browne>{{cite news|last=Browne|first=Anthony |title= Stop Blubbering: Whales are supposed to be protected but that doesn't stop the Japanese killing and eating hundreds of them every year. But does the West's moral outrage over the pursuit of our gentle leviathans amount to anything more than hypocrisy and cultural bullying? |periodical= The Observer|date= 9 September 2001 |url= https://www.theguardian.com/lifeandstyle/2001/sep/09/foodanddrink.features4 |access-date=14 June 2011}}</ref> Because a whale's fat is contained in the layer of [[blubber]] beneath the skin, and the muscle is high in myoglobin, the meat is a dark shade of red.<ref name=browne/><ref name=ark/> In Japan, where pilot whale meat can be found in certain restaurants and ''[[izakaya]]s'', the meat is sometimes served raw, as ''[[sashimi]]'', but just as often pilot whale steaks are marinated, cut into small chunks, and grilled.<ref name=ark/> When grilled, the meat is slightly flaky and quite flavorful, somewhat gamey, though similar to a quality cut of [[beef]], with distinct yet subtle undertones recalling its marine origin.<ref name=browne/><ref name=ark>{{cite journal |title= No matter how you slice it, whale tastes unique |year= 2002 |journal= Planet Ark |url= http://www.planetark.org/dailynewsstory.cfm/newsid/16090/story.htm |publisher= Reuters |access-date= 14 January 2011 |archive-date= 4 August 2017 |archive-url= https://web.archive.org/web/20170804233153/http://planetark.org/dailynewsstory.cfm/newsid/16090/story.htm |url-status= dead }}</ref><ref name=buncombe>{{cite journal |last= Buncombe |first= Andrew |title= The Whaling Debate: Arctic Lament |year= 2005 |journal= Ezilon |url= http://www.ezilon.com/information/article_11436.shtml |access-date= 14 January 2011 |url-status= dead |archive-url= https://web.archive.org/web/20120712111544/http://www.ezilon.com/information/article_11436.shtml |archive-date= 12 July 2012 |df= dmy-all }}</ref> |
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In both Japan and the Faroe Islands, the meat is contaminated with mercury and cadmium, causing a health risk for those who frequently eat it, especially children and pregnant women.<ref>Haslam, Nick (14 September 2003) [http://news.bbc.co.uk/2/hi/programmes/from_our_own_correspondent/3104494.stm Faroes' controversial whale hunt], ''BBC''.</ref> In November 2008, an article in ''[[New Scientist]]'' reported that research done on the Faroe Islands resulted in two chief medical officers recommending against the consumption of pilot whale meat, considering it to be too toxic.<ref>MacKenzie, Debora (28 November 2008) [https://www.newscientist.com/article/dn16159-faroe-islanders-told-to-stop-eating-toxic-whales.html Faroe Islanders told to stop eating 'toxic' whales], ''New Scientist''.</ref> In 2008, the local authorities recommended that pilot whale meat should no longer be eaten due to the contamination. This has resulted in reduced consumption, according to a senior Faroese health official.<ref>[http://www.wdcs.org/news.php?select=419 Pilot Whale Meat On The Way Out Of Faroese Food Culture] {{Webarchive|url=https://web.archive.org/web/20201102013621/http://www.wdcs.org/news.php?select=419 |date=2 November 2020 }}, wdcs.org (9 July 2009).</ref> |
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====Health concerns==== |
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In both Japan and the Faroe Islands, the meat is contaminated with mercury and cadmium, causing a health risk for those who frequently eat it, especially children and pregnant women.<ref>Haslam, Nick (14 September 2003) [http://news.bbc.co.uk/2/hi/programmes/from_our_own_correspondent/3104494.stm Faroes' controversial whale hunt], ''BBC''.</ref> In November 2008, an article in ''[[New Scientist]]'' reported that research done on the Faroe Islands resulted in two chief medical officers recommending against the consumption of pilot whale meat, considering it to be too toxic.<ref>MacKenzie, Debora (28 November 2008) [http://www.newscientist.com/article/dn16159-faroe-islanders-told-to-stop-eating-toxic-whales.html Faroe Islanders told to stop eating 'toxic' whales], ''New Scientist''.</ref> In 2008, the local authorities recommended that pilot whale meat should no longer be eaten due to the contamination. This has resulted in reduced consumption, according to a senior Faroese health official.<ref>[http://www.wdcs.org/news.php?select=419 Pilot Whale Meat On The Way Out Of Faroese Food Culture], wdcs.org (9 July 2009).</ref> |
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===Captivity=== |
===Captivity=== |
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{{Multiple image |
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Pilot whales, mostly short-finned pilot whales, have been kept in captivity. Since 1973, some long-finned pilot whales from New England waters were taken and temporarily kept in captivity.<ref name="Reeves 1984">{{cite journal|author=Reeves, R., Leatherwood, S.|year=1984|title=Live-Capture Fisheries for Cetaceans in U. S. and Canadian Waters, 1973–1982|journal=Rep. Int. Whal. Commn|volume=34|pages=497–507}}</ref> Short-finned pilot whales off southern California, Hawaii and Japan have been kept in [[aquarium]]s and [[oceanarium]]s. Several pilot whales from southern California and Hawaii were taken into captivity during the 1960s and early 1970s,<ref name="Reeves 1984"/><ref name="Walker 1975">{{cite journal|author=Walker, W. A.|year=1975|title=Review of the live-capture fishery for smaller cetaceans taken in southern California waters for public display, 1966–73|journal= Fish Res Board Can|volume=32|issue=7|pages=1197–1211|doi= 10.1139/f75-139}}</ref> two of which were placed at [[SeaWorld San Diego|SeaWorld]] in [[San Diego]]. During the 1970s and early '80s, six pilot whales were captured alive by drive hunts and taken for public display.<ref name="Ridgeway 1998"/> Pilot whales have low survival rates in captivity, with the average annual survival being 0.51 during the mid-1960s to early '70s.<ref name="Walker 1975"/> |
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| image1 = 6208-MarineLandPilotWhaleShow-Bubbles-1.jpg |
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| caption1 = Bubbles, the pilot whale, performing at [[Marineland of the Pacific]], Los Angeles 1962 |
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| image2 = Short-finned Pilot Whale (8793172995).jpg |
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| caption2 = A short-finned pilot whale performing at [[SeaWorld San Diego]], 2012 |
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}} |
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Pilot whales, mostly short-finned pilot whales, have been kept in captivity in various marine parks, arguably starting in the late 1940s.<ref>{{cite journal|last1=Kritzler|first1=H.|title=Observations on the pilot whale in captivity|journal=Journal of Mammalogy |date=1952 |volume=33 |issue=3 |pages=321–334 |doi=10.2307/1375770 |jstor=1375770}}</ref> Since 1973, some long-finned pilot whales from New England waters were taken and temporarily kept in captivity.<ref name="Reeves 1984">{{cite journal|author=Reeves, R., Leatherwood, S. |year=1984 |title=Live-Capture Fisheries for Cetaceans in U. S. and Canadian Waters, 1973–1982|journal=Rep. Int. Whal. Comm. |volume=34|pages=497–507}}</ref> Short-finned pilot whales off southern California, Hawaii and Japan have been kept in [[aquarium]]s and [[oceanarium]]s. Several pilot whales from southern California and Hawaii were taken into captivity during the 1960s and early 1970s,<ref name="Reeves 1984"/><ref name="Walker 1975">{{cite journal |author=Walker, W. A.|year=1975|title=Review of the live-capture fishery for smaller cetaceans taken in southern California waters for public display, 1966–73 |journal=J. Fish. Res. Board Can.|volume=32 |issue=7 |pages=1197–1211 |doi= 10.1139/f75-139}}</ref> two of which were placed at [[SeaWorld San Diego]]. During the 1970s and early 1980s, six pilot whales were captured alive by drive hunts and taken for public display.<ref name="Ridgeway 1998"/> |
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Pilot whales have historically had low survival rates in captivity, with the average annual survival being 0.51 years during the mid-1960s to early 1970s.<ref name="Walker 1975"/> There have been a few exceptions to the rule. Bubbles, a female short-finned pilot whale, who was displayed in Marineland of the Pacific and eventually at Sea World California, lived to be somewhere in her 50s when she eventually died on 12 June 2016.<ref>{{cite web |last1=McKirdy |first1=Euan |last2=Marco |first2=Tony |title=Bubbles, SeaWorld's oldest pilot whale, dies |date=12 June 2016 |url=http://www.cnn.com/2016/06/12/us/seaworld-bubbles-oldest-pilot-whale-dies/ |publisher=CNN |access-date=12 June 2016}}</ref> |
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In 1968, a pilot whale was captured, given the name Morgan, and trained by the U.S. Navy's Deep Ops to retrieve deeper-attached objects from the ocean floor. He dove a record depth of 1654 feet and was used for training until 1971.<ref>{{cite book |last1=Bowers |first1=Clark A. |last2=Henderson |first2=Richard S. |title=Project Deep Ops: Deep Object Recovery with Pilot and Killer Whales |date=1972}}</ref> |
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===Films=== |
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There are two documentaries entirely dedicated to the pilot whales. |
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* Full-length ''Cheetahs of the deep'' (49’, 2014, directed by Rafa Herrero Massieu<ref> |
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{{cite web |
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|url = https://www.imdb.com/name/nm7240182/bio |
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|title = Rafa Herrero Massieu profile at IMDb |
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|website = [[IMDb]] |
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</ref>) — tells about the way of life, features of social interaction, the subtleties of hunting, games and breeding on the example of a group of non-migrating short-finned pilot whales living between the Islands of Tenerife and [[La Gomera]] of the Canary archipelago. A curious feature of the film is that: “all marine mammals filmed in [[freediving]]”. |
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* Short film ''[[My Pilot, Whale]]'' (28’, 2014, directed by [[Alexander and Nicole Gratovsky]]<ref> |
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{{cite web |
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|url = https://www.imdb.com/title/tt4578360/ |
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|title = "My Pilot, Whale" film's profile on IMDb |
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|website = [[IMDb]] |
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|language = en |
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|access-date = 2020-03-30 |
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</ref>) demonstrates the possibility of interaction between humans and free-living pilot whales, offering the viewer a number of philosophical questions related to cetaceans: about their attitude to the world, what we have in common, what we — humans — can learn from them, and so on. The film has received a number awards of international film festivals.<ref> |
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{{cite web |
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|url = http://www.worldfest.org/wp-content/uploads/2016/05/WFH49FinalRemiAwards.pdf |
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|title = Platinum Remi award in the "Oceanography" category of the 49th International Houston Film Festival |
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|language = en |
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|date = 2016-05-01 |
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|access-date = 2020-01-27 |
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|archive-url = https://web.archive.org/web/20170729003922/http://www.worldfest.org/wp-content/uploads/2016/05/WFH49FinalRemiAwards.pdf |
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|archive-date = 2017-07-29 |
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}} |
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</ref><ref> |
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{{cite web |
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|author = Awareness Film Festival, Los Angeles |
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|url = http://theawarenessfestival.wix.com/awarenessfestival#!selections-2015/c1hw9 |
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|title = Winner in the nomination "Merit Award of Awareness" |
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|language = en |
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|access-date = 2020-01-27 |
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|archive-url =https://web.archive.org/web/20200127164909/http://web.archive.org/screenshot/https://theawarenessfestival.wixsite.com/awarenessfestival/selections-2015 |
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|archive-date = 2020-01-27 |
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}} |
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</ref> |
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==See also== |
==See also== |
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* [[Unihemispheric slow-wave sleep]] |
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*[[Unihemispheric slow-wave sleep]] |
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==References== |
==References== |
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{{ |
{{Reflist}} |
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==External links== |
==External links== |
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* [http://www.pilot-whales.org/ Pilot Whales.org] |
* [http://www.pilot-whales.org/ Pilot Whales.org] |
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* [http://cetus.ucsd.edu/voicesinthesea_org/species/dolphins/pilotWhale.html Voices in the Sea] {{Webarchive|url=https://web.archive.org/web/20160306083657/http://cetus.ucsd.edu/voicesinthesea_org/species/dolphins/pilotWhale.html |date=6 March 2016 }} |
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{{Cetacea|O.}} |
{{Cetacea|O.}} |
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{{Odontoceti|D.}} |
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{{Taxonbar|from=Q459616}} |
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[[Category: |
[[Category:Globicephala| ]] |
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[[Category: |
[[Category:Globicephalinae]] |
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[[Category: |
[[Category:Cosmopolitan mammals]] |
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[[Category: |
[[Category:Animals that use echolocation]] |
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[[Category: |
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Latest revision as of 19:17, 12 December 2024
Pilot whales Temporal range: Pliocene to recent
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---|---|
Size of short-finned pilot whale compared to an average human | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Artiodactyla |
Infraorder: | Cetacea |
Family: | Delphinidae |
Subfamily: | Globicephalinae |
Genus: | Globicephala Lesson, 1828 |
Type species | |
Delphinus globiceps[1] Cuvier, 1812
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Species | |
Exclusive range of short-finned pilot whale Exclusive range of long-finned pilot whale Regions of sympatry
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Synonyms | |
Globicephalus |
Pilot whales are cetaceans belonging to the genus Globicephala. The two extant species are the long-finned pilot whale (G. melas) and the short-finned pilot whale (G. macrorhynchus). The two are not readily distinguishable at sea, and analysis of the skulls is the best way to distinguish between the species. Between the two species, they range nearly worldwide, with long-finned pilot whales living in colder waters and short-finned pilot whales living in tropical and subtropical waters. Pilot whales are among the largest of the oceanic dolphins, exceeded in size only by the orca. They and other large members of the dolphin family are also known as blackfish.
Pilot whales feed primarily on squid, but will also hunt large demersal fish such as cod and turbot. They are highly social and may remain with their birth pod throughout their lifetime. Short-finned pilot whales are one of the few non-primate mammal species in which females go through menopause, and postreproductive females continue to contribute to their pod. Pilot whales are notorious for stranding themselves on beaches, but the reason behind this is not fully understood. Marine biologists have shed some light on the matter, suggesting that it is due to the mammals inner ear (their principal navigational sonar) being damaged from noise pollution in the ocean, such as from cargo ships or military exercises.[2] The conservation status of short-finned and long-finned pilot whales has been determined to be least concern.
Naming
[edit]The animals were named "pilot whales" because pods were believed to be "piloted" by a leader.[3][4] They are also called "pothead whales" and "blackfish". The genus name is a combination of the Latin word globus ("round ball" or "globe") and the Greek word Kephale ("head").[3][4]
Taxonomy and evolution
[edit]Pilot whales are classified into two species; the long-finned pilot whale (Globicephala melas) and the short-finned pilot whale (G. macrorhynchus). The short-finned pilot whale was described, from skeletal materials only, by John Edward Gray in 1846. He presumed from the skeleton that the whale had a large beak. The long-finned pilot whale was first classified by Thomas Stewart Traill in 1809 as Delphinus melas.[5] Its scientific name was eventually changed to Globicephala melaena. Since 1986, the specific name of the long-finned pilot whale was changed to its original form melas.[6] Other species classifications have been proposed but only two have been accepted.[7] There exist geographic forms of short-finned pilot whales off the east coast of Japan,[8] which comprise genetically isolated stocks.[9]
Fossils of an extinct relative, Globicephala baereckeii, have been found in Pleistocene deposits in Florida.[3] Another Globicephala dolphin was discovered in Pliocene strata in Tuscany, Italy, and was named G. etruriae.[3] Evolution of Tappanaga, the endemic, larger form of short-finned pilots found in northern Japan, with similar characteristics to the whales found along Vancouver Island and northern USA coasts,[10] has indicated that the geniture of this form could be caused by the extinction of long-finned pilots in north Pacific in the 12th century, where Magondou, the smaller, southern type possibly filled the former niches of long-finned pilots, adapting and colonizing into colder waters.[11]
Description
[edit]Pilot whales are mostly dark grey, brown, or black, but have some light areas such as a grey saddle patch behind the dorsal fin.[4] Other light areas are an anchor-shaped patch under the chin, a faint blaze marking behind the eye, a large marking on the belly, and a genital patch.[4] The dorsal fin is set forward on the back and sweeps backwards. A pilot whale is more robust than most dolphins and has a distinctive large, bulbous melon.[4] Pilot whales' long, sickle-shaped flippers and tail stocks are flattened from side to side.[4] Male long-finned pilot whales develop more circular melons than females,[4] although this does not seem to be the case for short-finned pilot whales off the Pacific coast of Japan.[12]
Long-finned and short-finned pilot whales are so similar, it is difficult to tell the two species apart.[3] They were traditionally differentiated by the length of the pectoral flippers relative to total body length and the number of teeth.[7] The long-finned pilot whale was thought to have 9–12 teeth in each row and flippers one-fifth of total body length, compared to the short-finned pilot whale with its 7–9 teeth in each row and flippers one-sixth of total body length.[4] Studies of whales in the Atlantic showed much overlap in these characteristics between the species, making them clines instead of distinctive features.[4] Thus, biologists have since used skull differences to distinguish the two species.[3][4]
The size and weight depend on the species, as long-finned pilot whales are generally larger than short-finned pilot whales.[12][13] Their lifespans are about 45 years in males and 60 years in females for both species. Both species exhibit sexual dimorphism. Adult long-finned pilot whales reach a body length of approximately 6.5 m, with males being 1 m longer than females.[14] Their body mass reaches up to 1,300 kg in females and up to 2,300 kg in males.[15] For short-finned pilot whales, adult females reach a body length of about 5.5 m, while males reach 7.2 m and may weigh up to 3,200 kg.[15]
Distribution and habitat
[edit]Pilot whales can be found in oceans nearly worldwide, but data about current population sizes is deficient. The long-finned pilot whale prefers slightly cooler waters than the short-finned and is divided into two populations. The smaller group is found in a circumpolar band in the Southern Ocean from about 20 to 65°S. It may be sighted off the coasts of Chile, Argentina, South Africa, Australia, and New Zealand.[16] An estimated more than 200,000 individuals were in this population in 2006. The second, much larger, population inhabits the North Atlantic Ocean, in a band from South Carolina in the United States across to the Azores and Morocco at its southern edge and from Newfoundland to Greenland, Iceland, and northern Norway at its northern limit. This population was estimated at 778,000 individuals in 1989. It is also present in the western half of the Mediterranean Sea.[16]
The short-finned pilot whale is less populous. It is found in temperate and tropical waters of the Indian, Atlantic and Pacific Oceans.[17] Its population overlaps slightly with the long-finned pilot whale in the temperate waters of the North Atlantic and Southern Oceans.[3] About 150,000 individuals are found in the eastern tropical Pacific Ocean. More than 30,000 animals are estimated in the western Pacific, off the coast of Japan. Pilot whales are generally nomadic, but some populations stay year-round in places such as Hawaii and parts of California.[3] They prefer the waters of the shelf break and slope.[3] Once commonly seen off of Southern California, short-finned pilot whales disappeared from the area after a strong El Niño year in the early 1980s, according to the National Oceanic and Atmospheric Administration.[18] In October 2014, crew and passengers on several boats spotted a pod of 50–200 off Dana Point, California.[18]
Behavior and life history
[edit]Foraging and parasites
[edit]Although pilot whales are not known to have many predators, possible threats come from humans and killer whales. Both species eat primarily squid.[19] The whales make seasonal inshore and offshore movements in response to the dispersal of their prey.[3] Fish that are consumed include Atlantic cod, Greenland turbot, Atlantic mackerel, Atlantic herring, hake, and spiny dogfish in the northwest Atlantic.[3] In the Faroe Islands, whales mostly eat squid, but will also eat fish species such as greater argentine and blue whiting. However, Faroe whales do not seem to feed on cod, herring, or mackerel, even when they are abundant.[20]
Pilot whales generally take several breaths before diving for a few minutes. Feeding dives may last over ten minutes. They are capable of diving to depths of 600 meters, but most dives are to a depth of 30–60 m. Shallow dives tend to take place during the day, while deeper ones take place at night. When making deep dives, pilot whales often make fast sprints to catch fast-moving prey such as squid.[21] Compared to sperm whales and beaked whales, foraging short-finned pilot whales are more energetic at the same depth. When they reach the end of their dives, pilot whales will sprint, possibly to catch prey, and then make a few buzzes.[21] This is unusual, considering that deep-diving, breath-holding animals would be expected to swim slowly to conserve oxygen. The animal's high metabolism possibly allows it to sprint at deep depths, which would also give it shorter diving periods than some other marine mammals.[21] This may also be the case for long-finned pilot whales.[22] In 2024, a gps-fitted long-finned pilot whale recorded a diving depth over 1,100 meters.[23]
Pilot whales are often infested with whale lice, cestodes, and nematodes.[4] They also can be hosts to various pathogenic bacteria and viruses, such as Streptococcus, Pseudomonas, Escherichia, Staphylococcus, and influenza.[4] One sample of Newfoundland pilot whales found that the most common illness was an upper respiratory tract infection.[24]
Social structure
[edit]Both species live in groups of 10–30, but some groups may number 100 or more. Data suggest the social structures of pilot whale pods are similar to those of "resident" killer whales. The pods are highly stable and the members have close matrilineal relationships.[3] Pod members are of various age and sex classes, although adult females tend to outnumber adult males. They have been observed making various kin-directed behaviors, such as providing food.[25] Numerous pods will temporarily gather, perhaps to allow individuals from different pods to interact and mate,[4] as well as provide protection.[13]
Both species are loosely polygynous.[13] Data suggest both males and females remain in their mother's pod for life; despite this, inbreeding within a pod does not seem to occur.[4] During aggregations, males will temporarily leave their pods to mate with females from other pods.[26] Male reproductive dominance or competition for mates does not seem to exist.[27] After mating, a male pilot whale usually spends only a few months with a female, and an individual may sire several offspring in the same pod.[28] Males return to their own pods when the aggregations disband, and their presence may contribute to the survival of the other pod members.[26] No evidence of "bachelor" groups has been found.[13][26]
Pilot whale pods off southern California have been observed in three different groups: traveling/hunting groups, feeding groups and loafing groups.[29] In traveling/hunting groups, individuals position themselves in chorus lines stretching two miles long, with only a few whales underneath.[30] Sexual and age-class segregation apparently occurs in these groups.[29] In feeding groups, individuals are very loosely associated, but may move in the same direction.[29] In loafing groups, whales number between 12 and 30 individuals resting. Mating and other behaviors may take place.[29]
Reproduction and lifecycle
[edit]Pilot whales have one of the longest birth intervals of the cetaceans,[3] calving once every three to five years. Most matings and calvings occur during the summer for long-finned pilot whales.[31] For short-finned pilot whales of the Southern Hemisphere, births are at their highest in spring and autumn, while in Northern Hemisphere, the time in which calving peaks can vary by population.[31] For long-finned pilot whales, gestation lasts 12–16 months, and short-finned pilot whales have a 15-month gestation period.[3]
The calf nurses for 36–42 months, allowing for extensive mother-calf bonds.[3] Young pilot whales will take milk until as old as 13–15 years of age. Short-finned pilot whale females will go through menopause,[32] but this is not as common in females of long-finned pilot whales.[33] Postreproductive females possibly play important roles in the survival of the young.[25][34] Postreproductive females will continue to lactate and nurse young. Since they can no longer bear young of their own, these females invest in the current young, allowing them to feed even though they are not their own.[3] Short-finned pilot whales grow more slowly than long-finned pilot whales. For the short-finned pilot whale, females become sexually mature at 9 years old and males at about 13–16 years.[3] For the long-finned pilot whale, females reach maturity at around eight years and males at around 12 years.[3]
Vocalizations
[edit]Pilot whales emit echolocation clicks for foraging and whistles and burst pulses as social signals (e.g. to keep contact with members of their pod). With active behavior, vocalizations are more complex, while less-active behavior is accompanied by simple vocalizations. Differences have been found in the calls of the two species.[35] Compared with short-finned pilot whales, long-finned pilot whales have relatively low-frequency calls with narrow frequency ranges.[35] In one study of North Atlantic long-finned pilot whales, certain vocalizations were heard to accompany certain behaviors.[36] When resting or "milling", simple whistles are emitted.[36] Surfacing behavior is accompanied by more complex whistles and pulsed sounds.[36] The number of whistles made increases with the number of subgroups and the distance in which the whales are spread apart.[36]
A study of short-finned pilot whales off the southwest coast of Tenerife in the Canary Islands has found the members of a pod maintained contact with each other through call repertoires unique to their pod.[37] A later study found, when foraging at around 800 m deep, short-finned pilot whales make tonal calls.[38] The number and length of the calls seem to decrease with depth despite being farther away from conspecifics at the surface. As such, the surrounding water pressure affects the energy of the calls, but it does not appear to affect the frequency levels.[38]
When in stressful situations, pilot whales produce "shrills" or "plaintive cries", which are variations of their whistles.[39] To elude predators, long-finned pilot whales off the southern coast of Australia have been observed to mimic the calls of orcas while scavenging for food. This behaviour is thought to deter orca pods from approaching the pilot whales.[40]
Antagonistic interactions with other species
[edit]Pilot whales have been occasionally observed mobbing or chasing other species of cetaceans. In several parts of the world, including off Iceland, long-finned pilot whales have been frequently documented chasing killer whales.[41] The reasons for these chases are unknown, but it has been proposed that they might be due to either competition for prey or an anti-predation strategy. In 2021 an adult female killer whale with a newborn pilot whale travelling alongside her was observed off Western Iceland, leading scientists to question whether the relationship between these species might be far more complex than previously suggested.[42] It is not known whether the newborn was adopted or abducted, but this same female killer whale was seen a year later interacting with a larger group of pilot whales.
Based on experimentation involving familiar sounds of Orcas that consume fish and unfamiliar vocalizations of mammal-hunting Killer Whales, one study suggests that long-finned pilot whales can distinguish between familiar and unaccustomed types of Orca, noting behavioral differences like the ceasing of feeding when mammal-hunting Orcas' sounds were played. The study suggests that antagonistic interactions against fish-eating Killer Whales could either be an anti-predatory behavior or an attempt to maintain territory, while actions done in response to mammal-hunting Killer Whales could be a response to a more dangerous threat. [43]
Stranding
[edit]Of the cetaceans, pilot whales are among the most common stranders.[44] Because of their strong social bonds, whole groups of pilot whales will strand. Single stranders have been recorded and these are usually diseased.[3] Group stranding tends to be of mostly healthy individuals. Several hypotheses have been proposed to explain group strandings.[3] When using magnetic fields for navigation, the whales have been suggested to get perplexed by geomagnetic anomalies or they may be following a sick member of their group that got stranded.[3] The pod also may be following a member of high importance that got stranded and a secondary social response makes them keep returning.[4] Researchers from New Zealand have successfully used secondary social responses to keep a stranding pod of long-finned pilot whales from returning to the beach.[45] In addition, the young members of the pod were taken offshore to buoys, and their distress calls lured the older whales back out to sea.[45]
In September 2022, nearly 200 pilot whales died after becoming stranded on Ocean Beach, part of Tasmania's west coast. Authorities said only about 35 survived of the 230 that were stranded.[46]
Human interaction
[edit]The IUCN lists long-finned pilot whales as "least concern" in the Red List of Threatened Species. Long-finned pilot whales in the North and Baltic Seas are listed in Appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). Those from northwest and northeast Atlantic may also need to be included to Appendix II of CMS.[16] The short-finned pilot whale is listed on Appendix II of CITES.[17]
Hunting
[edit]The long-finned pilot whale has traditionally been hunted by "driving", which involves many hunters and boats gathering in a semicircle behind a pod of whales close to shore, and slowly driving them towards a bay, where they become stranded and are then slaughtered. This practice was common in both the 19th and 20th centuries. The whales were hunted for bone, meat, oil, and fertilizer. In the Faroe Islands, pilot whale hunting started at least in the 16th century,[4] and continued into modern times, with thousands being killed during the 1970s and 1980s.[47][48] In other parts of the North Atlantic, such as Norway, West Greenland, Ireland and Cape Cod, pilot whales have also been hunted, but to a lesser extent.[49][50] One fishery at Cape Cod harvested 2,000–3,000 whales per year during the late 19th and early 20th centuries.[51] Newfoundland's long-finned pilot whale fishery was at its highest in 1956, but declined shortly after[47] and is now defunct. In the Southern Hemisphere, exploitation of long-finned pilot whales has been sporadic and low.[47] Currently, long-finned pilot whales are only hunted at the Faroe Islands and Greenland.[16]
According to the IUCN the harvesting of this species for food in the Faroe Islands and Greenland has not resulted in any detectable declines in abundance.[52]
The short-finned pilot whale has also been hunted for many centuries, particularly by Japanese whalers. Between 1948 and 1980, hundreds of whales were exploited at Hokkaido and Sanriku in the north and Taiji, Izu, and Okinawa in the south.[13] These fisheries were at their highest in the late 1940s and early 1950s;[13] 2,326 short-finned pilot whales were harvested in the mid- to late 1980s.[17] This had decreased to about 400 per year by the 1990s.
Pilot whales have also fallen victim to bycatches. In one year, around 30 short-finned pilot whales were caught by the squid round-haul fishery in southern California.[53] Likewise, California's drift gill net fishery took around 20 whales a year in the mid-1990s.[4] In 1988, 141 whales caught on the east coast of the U.S. were taken by the foreign Atlantic mackerel fishery, which forced it to be shut down.[4]
Pollution
[edit]As with other marine mammals, pilot whales are susceptible to certain pollutants. Off the Faroes, France, the UK, and the eastern US, pilot whales were found to have been contaminated with high amounts of DDT and PCB.[4] Pollutants such as DDT and mercury can be passed from mothers to their babies during gestation and lactation.[54] The Faroes whales have also been contaminated with cadmium and mercury.[55] However, pilot whales from Newfoundland and Tasmania were found to have had very low levels of DDT.[4] Short-finned pilot whales off the west coast of the US have had high amounts of DDT and PCB in contrast to the low amounts found in whales from Japan and the Antilles.[4]
Cuisine
[edit]Pilot whale meat is available for consumption in very few areas of Japan, mainly along the central Pacific coast, and also in other areas of the world, such as the Faroe Islands. The meat is high in protein (higher than beef) and low in fat.[56] Because a whale's fat is contained in the layer of blubber beneath the skin, and the muscle is high in myoglobin, the meat is a dark shade of red.[56][57] In Japan, where pilot whale meat can be found in certain restaurants and izakayas, the meat is sometimes served raw, as sashimi, but just as often pilot whale steaks are marinated, cut into small chunks, and grilled.[57] When grilled, the meat is slightly flaky and quite flavorful, somewhat gamey, though similar to a quality cut of beef, with distinct yet subtle undertones recalling its marine origin.[56][57][58]
In both Japan and the Faroe Islands, the meat is contaminated with mercury and cadmium, causing a health risk for those who frequently eat it, especially children and pregnant women.[59] In November 2008, an article in New Scientist reported that research done on the Faroe Islands resulted in two chief medical officers recommending against the consumption of pilot whale meat, considering it to be too toxic.[60] In 2008, the local authorities recommended that pilot whale meat should no longer be eaten due to the contamination. This has resulted in reduced consumption, according to a senior Faroese health official.[61]
Captivity
[edit]Pilot whales, mostly short-finned pilot whales, have been kept in captivity in various marine parks, arguably starting in the late 1940s.[62] Since 1973, some long-finned pilot whales from New England waters were taken and temporarily kept in captivity.[63] Short-finned pilot whales off southern California, Hawaii and Japan have been kept in aquariums and oceanariums. Several pilot whales from southern California and Hawaii were taken into captivity during the 1960s and early 1970s,[63][64] two of which were placed at SeaWorld San Diego. During the 1970s and early 1980s, six pilot whales were captured alive by drive hunts and taken for public display.[4]
Pilot whales have historically had low survival rates in captivity, with the average annual survival being 0.51 years during the mid-1960s to early 1970s.[64] There have been a few exceptions to the rule. Bubbles, a female short-finned pilot whale, who was displayed in Marineland of the Pacific and eventually at Sea World California, lived to be somewhere in her 50s when she eventually died on 12 June 2016.[65] In 1968, a pilot whale was captured, given the name Morgan, and trained by the U.S. Navy's Deep Ops to retrieve deeper-attached objects from the ocean floor. He dove a record depth of 1654 feet and was used for training until 1971.[66]
Films
[edit]There are two documentaries entirely dedicated to the pilot whales.
- Full-length Cheetahs of the deep (49’, 2014, directed by Rafa Herrero Massieu[67]) — tells about the way of life, features of social interaction, the subtleties of hunting, games and breeding on the example of a group of non-migrating short-finned pilot whales living between the Islands of Tenerife and La Gomera of the Canary archipelago. A curious feature of the film is that: “all marine mammals filmed in freediving”.
- Short film My Pilot, Whale (28’, 2014, directed by Alexander and Nicole Gratovsky[68]) demonstrates the possibility of interaction between humans and free-living pilot whales, offering the viewer a number of philosophical questions related to cetaceans: about their attitude to the world, what we have in common, what we — humans — can learn from them, and so on. The film has received a number awards of international film festivals.[69][70]
See also
[edit]References
[edit]- ^ Wilson, D. E.; Reeder, D. M., eds. (2005). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. ISBN 978-0-8018-8221-0. OCLC 62265494.
- ^ "Sonic Sea". Brown Media Archives and Peabody Awards Collection, University of Georgia.
- ^ a b c d e f g h i j k l m n o p q r s t u Olson, P.A. (2008) "Pilot whale Globicephala melas and G. muerorhynchus" pp. 847–52 in Encyclopedia of Marine Mammals, Perrin, W. F., Wursig, B., and Thewissen, J. G. M. (eds.), Academic Press; 2nd edition, ISBN 0-12-551340-2
- ^ a b c d e f g h i j k l m n o p q r s t u v Ridgway, S. H. (1998). Handbook of Marine Mammals: The second book of dolphins and the porpoises, Volume 6, Elsevier. pp. 245–69. ISBN 0-12-588506-7
- ^ Traill T. S. (1809). "Description of a new species of whale, Delphinus melas". In a letter from Thomas Stewart Traill, M.D. to Mr. Nicholson". Journal of Natural Philosophy, Chemistry, and the Arts. 1809: 81–83.
- ^ Starting, Jones Jr; Carter, D.C.; Genoways, H.H.; Hoffman, R.S.; Rice, D.W.; Jones (1986). "Revised checklist of North American mammals north of Mexico". Occ Papers Mus Texas Tech Univ. 107: 5.
- ^ a b van Bree, P.J.H. (1971). "On Globicephala seiboldi, Gray 1846, and other species of pilot whales. (Notes on cetacean, Delphinoidea III)". Beaufortia. 19: 79–87.
- ^ Kasuya, T., Sergeant, D. E., Tanaka, K. (1986). "Segregation of two forms of short-finned pilot whales off the Pacific coast of Japan" (PDF). Scientific Reports of the Whales Research Institute. 39: 77–90.
{{cite journal}}
: CS1 maint: multiple names: authors list (link) - ^ Wada, S. (1988). "Genetic differentiation between two forms of short-finned pilot whales off the Pacific coast of Japan" (PDF). Sci Rep Whales Res Inst. 39: 91–101.
- ^ Hidaka T. Kasuya T. Izawa K. Kawamichi T. 1996. The encyclopaedia of animals in Japan (2) - Mammals 2. ISBN 9784582545524 (9784582545517) (4582545521). Heibonsha
- ^ Amano M. (2012). "みちのくの海のイルカたち(特集 みちのくの海と水族館の海棲哺乳類)" (PDF). Isana 56. Faculty of Fisheries of University of Nagasaki, Isanakai: 60–65. Retrieved 9 March 2017.
- ^ a b Yonekura, M., Matsui, S. & Kasuya, T. (1980). "On the external characters of Globicephala macrorhynchus off Taiji, Pacific coast of Japan". Sci. Rep. Inst. 32: 67–95. ISSN 0083-9086.
{{cite journal}}
: CS1 maint: multiple names: authors list (link) - ^ a b c d e f Kasuya, T.; Marsh, H. (1984). "Life history and reproductive biology of the short-finned pilot whale, Globicephala macrorhynchus, off the Pacific Coast Japan" (PDF). Rep. Int. Whal. Comm. 6: 259–310. Archived from the original (PDF) on 19 May 2017. Retrieved 15 May 2011.
- ^ Bloch D, Lockyer C, Zachariassen M (1993). "Age and growth parameters of the long-finned pilot whale off the Faroe Islands". Rep. Int. Whal. Comm. 14: 163–208.
- ^ a b Jefferson, T. A, Webber, M. A., Pitman, R. L., (2008) Marine mammals of the world. Elsevier, Amsterdam.
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External links
[edit]- Pilot Whales.org
- Voices in the Sea Archived 6 March 2016 at the Wayback Machine