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The '''southern right whale dolphin''' (''Lissodelphis peronii'') is a small and slender species of mammal found in cool waters of the Southern Hemisphere. The dolphin is one of two species of [[right whale dolphin]]; ''Lissodelphis'', the other, the [[northern right whale dolphin]], is found in deep oceans of the Northern Hemisphere.
The '''southern right whale dolphin''' (''Lissodelphis peronii'') is a small and slender species of mammal, found in cool waters of the [[Southern Hemisphere]]. It is one of two species of [[right whale dolphin]]; ''Lissodelphis'', a [[genus]] characterized by the lack of a dorsal fin. The other species, the [[northern right whale dolphin]] (''Lissodelphis borealis''), is found in deep oceans of the [[Northern Hemisphere]] and has a different [[pigmentation]] pattern than the southern right whale dolphin.


==Description==
==Description==
Southern right whale dolphins can be easily distinguished from other cetacean species within their range as they are the only dolphins without dorsal fins in the Southern Hemisphere. They have streamlined and graceful bodies, a single blowhole and a short and defined beak, possessing between 39 and 50 teeth in each row of both jaws.<ref name=CiteJefferson>{{Cite book | last1 = Jefferson | first1 = Thomas | last2 = Newcomer | first2 = Michael W. | last3 = Leatherwood | first3 = Stephen | last4 = Van Waerebeek | first4 = Koen | year = 1994 | title = Right Whale Dolphins Lissodelphis borealis (Peale, 1848) and Lissodelphis peronii (Lacépède, 1804) | publisher = Academic Press Ltd | pp = 335-362 | isbn =0-12-588505-9 | url = https://www.researchgate.net/publication/257748539_Right_Whale_Dolphins_Lissodelphis_borealis_Peale_1848_and_Lissodelphis_peronii_Lacepede_1804 }}</ref><ref name=EOMM>{{cite encyclopedia
Southern right whale dolphins are the only dolphins without dorsal fins in the Southern Hemisphere. They are smaller than northern right whale dolphins and have more white on their heads and sides. They have slim, graceful bodies which are black on the upper side and white underneath. Their flippers are mainly white and are small and curved. Their flukes are small with a notch in the middle and concave trailing edges. Their beaks are small but distinct. They have between 43 and 49 teeth in each row of both jaws.
|last=Lipsky |first=Jessica D.
|editor=Perrin, W. F. |editor2=Wursig, B. |editor3=Thewissen, J. G. M.
|encyclopedia=Encyclopedia of Marine Mammals
|title=Right Whale Dolphins (''Lissodelphis borealis, L. Peroni'')
|url=https://books.google.com/books?id=2rkHQpToi9sC&pg=PA963 |accessdate=25 January 2020
|year=2008 |publisher=Academic Press
|isbn=978-0-12-373553-9|pages=958–962}}</ref>


A sharp dividing line separates the black dorsal part from the white ventral part of the body, running from the tail stock forward, dipping down to the flipper insertion and sweeping back up, below the eyes, to cross the [[melon (cetacean)|melon]] between the blowhole and snout crease.<ref name=CiteJefferson /><ref name=CiteYazdi>{{cite journal |last1=Yazdi |first1=Parissa |title=A possible hybrid between the dusky dolphin (Lagenorhynchus obscurus) and the southern right whale dolphin (Lissodelphis peronii) |journal=Aquatic Mammals |date=2002 |volume=28 |pages=211-217 |url=https://www.researchgate.net/publication/267956869_A_possible_hybrid_between_the_dusky_dolphin_Lagenorhynchus_obscurus_and_the_southern_right_whale_dolphin_Lissodelphis_peronii}}</ref><ref name=EOMM /> Younger individuals can be grey/brownish dorsally but develop adult coloration within the first year.<ref name=CiteCruickshank>{{cite journal |last1=Cruickshank |first1=R. A. |last2=Brown |first2=S. G. |title=Recent observations and some historical records of southern right-whale dolphins Lissodelphis peronii |journal=Fisheries Bulletin of South Africa |date=1981 |volume=15 |pages=109-121}}</ref><ref name=CiteJefferson /><ref name=EOMM /> The flippers of the southern right whale dolphins are small, recurved, predominantly white and located about one-quarter of the way back from the snout tip. Their flukes are small, have a white underside and dark grey upper side, with a notch in the middle and concave trailing edges.<ref name=CiteJefferson />
The distribution range of the species is subtropical to subantarctic oceans of the Southern Hemisphere. The range and total population have not been estimated or closely studied. Large populations are recorded off the western coasts of South America, where they are targeted by whaling operations; it is described as abundant in this region and off the coast of New Zealand. The range is associated with cold currents up the western and southern coasts of Africa, with a concentration recorded near Namibia.<ref name="SPRAT">{{cite web|url=http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=44|title=Lissodelphis peronii|work=Species Profile and Threats Database|publisher=Department of the Environment, Water, Heritage and the Arts, Canberra.|accessdate=2009-07-16}}</ref>
The species is recorded with other cetaceans such as ''Lagenorhynchus obscurus'', the [[dusky dolphin]], and the pilot whale ''[[Globicephala macrorhynchus]]''.<ref name="MarineBio">{{cite web|url=http://marinebio.org/species.asp?id=352|title=''Lissodelphis borealis'' Right Whale Dolphin |publisher=MarineBio|accessdate=2009-07-15}}</ref>
The southern right whale dolphin travels in groups of up to 1000 individuals, 52 being the average group size. The mass stranding of ''L. peronii'' on beaches, as many as 77, have been recorded.<ref name="SPRAT" />


Variability in the size of these black and white areas exists.<ref name=CiteBaker>{{cite book |last1=Baker |first1=A. N. |title=The Southern Right Whale dolphin, Lissodelphis peroni (Lacépède) in Australasian water |date=1981 |publisher=National Museum of New Zealand |location=Wellington |pages=17-34 |edition=2 |url=https://www.worldcat.org/title/southern-right-whale-dolphin-lissodelphis-peroni-lacepede-in-australasian-water/oclc/889342917}}</ref><ref name=CiteBarrie>{{cite journal |last1=Rose |first1=Barrie |last2=Payne |first2=Andrew I. L. |title=Occurrence and behavior of the southern right whale dolphin Lissodelphis peronii off Namibia |journal=Marine Mammal Science |date=1991 |volume=7 |issue=1 |pages=25-34 |url=https://doi.org/10.1111/j.1748-7692.1991.tb00547.x}}</ref> More extensive anomalous pigmentation has been observed, with records of pure all-white individuals,<ref name=CiteBrown>{{cite journal |last1=Brown |first1=S. |title=Recent sight records of southern right whale dolphins in the Pacific Ocean |journal=Marine Observer |date=1973 |volume=43 |pages=78-80}}</ref><ref name=CiteWatson>{{cite book |last1=Watson |first1=Lyall |title=Sea guide to whales of the world |date=1981 |publisher=Hutchinson |location=London |isbn=9780091466008 |page=302 |url=https://www.worldcat.org/title/sea-guide-to-whales-of-the-world/oclc/8448534}}</ref> as well as [[melanistic]] (all-black) individuals.<ref name=CiteNewcomer>{{cite journal |last1=Newcomer |first1=Michael W. |last2=Jefferson |first2=Thomas A. |last3=Brownell |first3=Robert L. |title=Lissodelphis peronii |journal=Mammalian Species |date=27 December 1996 |issue=531 |pages=1-5 |doi=10.2307/3504326 |url=https://academic.oup.com/mspecies/article/doi/10.2307/3504326/2600545 |issn=0076-3519}}</ref><ref name=CiteVisser>{{cite journal |last1=Visser |first1=Ingrid |last2=Fertl |first2=Dagmar |last3=Pusser |first3=L. |title=Melanistic southern right-whale dolphins (Lissodelphins peronii) off Kaikoura, New Zealand, with records of other anomously all-black cetaceans |journal=New Zealand Journal of Marine and Freshwater Research |date=2004 |volume=38 |issue=5 |pages=833-836 |doi=10.1080/00288330.2004.9517282 |url=https://www.researchgate.net/publication/242310887_Melanistic_southern_right-whale_dolphins_Lissodelphins_peronii_off_Kaikoura_New_Zealand_with_records_of_other_anomously_all-black_cetaceans}}</ref> In 1998, a potential hybrid of a southern right whale dolphin and a [[Dusky dolphin]] (''Lagenorhynchus obscurus'') was observed and subsequently described in 2002. This animal showed intermediate morphological features between the two species.<ref name=CiteYazdi />
The species was first published by [[Bernard Germain de Lacépède]] in 1804. The genus ''Lissodelphis'', is placed within the [[Delphinidae]], the oceanic dolphin family of [[cetacean]]s.<ref name="ITIS" /> The name of the genus was derived from Greek ''lisso'', smooth, and ''delphis''. The specific epithet ''peronii'' commemorates [[François Péron]], who saw the species near [[Tasmania]] during an expedition in 1800.<ref name="Common name">{{cite web|url=http://library.thinkquest.org/C0124382/new_page_17.htm|title=Southern Right Whale Dolphin|last=Fertl|first=Dagmar|work=Whales & Whale Spotting|accessdate=2009-07-16}}</ref> The [[common name]]s for the species include southern right-whale dolphin and snake porpoise.<ref name="eol">{{cite web|url=http://www.eol.org/pages/328528|title=Lissodelphis peronii (Peale, 1848)|encyclopedia=Encyclopedia of life|publisher=eol.org|accessdate=2009-07-15}}</ref> Both species in the genus are also referred by the name "right whale dolphin", a name derived from the [[right whales]] (''Eubalaena'') which also lack a dorsal fin.<ref name="SPRAT" />


Newborn calves measure around {{Convert|86|cm|abbr=on}} in length and weigh around {{Convert|5|kg|abbr=on}}, while adults range between {{Convert|2.18|and|2.5|m|abbr=on}} and weight between {{Convert|60|-|100|kg|abbr=on}} on average.<ref name=CiteJefferson /><ref name=CiteNewcomer /><ref name=EOMM />. The maximum weight for southern Right Whale Dolphins is 116 kg, with maximum lengths reaching {{Convert|297|cm|abbr=on}} in males and {{Convert|230|cm|abbr=on}} in females but few specimens have been examined and it is expected they grow larger.<ref name=CiteBaker /> On average, males tend to grow slightly larger than females. Little is known of this species’ reproductive biology. Research suggests that males reach sexual maturity at lengths between {{Convert|212|-|220|cm|abbr=on}} and females between {{Convert|206|-|212|cm|abbr=on}}.<ref name=CiteJefferson />
This delphinid was not targeted by whaling operations of the 19th century, although it was sometimes caught for meat. The species is harvested by small fisheries in Peru; other threats include drowning and accidental capture in fishing operations elsewhere. Large numbers of ''L. peronii'' are sometimes taken by [[gillnet]]ting and [[longline fishing]] in oceans off the southern coast of Australia.<ref name="SPRAT" />


==Population status==
Southern right whale dolphins are presumably eaten by sharks and [[killer whale]]s. ''L. peronii'' itself preys on an undetermined range of fish, but is known to eat crustaceans, squid, and species of [[myctophid]]s. Their diet could possibly include [[euphausiid]]s (krill). Little is known of their particular habits, and it is not known whether they search for their food near the surface or at greater depths.<ref name="SPRAT" />
There are no current global abundance and mortality estimates of the species although it is considered a fairly common and abundant species along its range,<ref name=CiteJefferson /> particularly in Chile<ref name=CiteWaer1991 />. The very low sighting rate is most likely caused by a lack of sampling effort and due to the difficulties of sighting the animals in their offshore habitat.


==Geographic range/distribution==
===Characteristics===
Southern right whale dolphins have a circumpolar distribution across the [[Southern Hemisphere]], generally occurring in cool temperate to Sub-Antarctic waters between 30°S and 65°S.<ref name=CiteWaer1991>{{cite journal |last1=Van Waerebeek |first1=K. |last2=Canto |first2=J. |last3=Gonzalez |first3=J. |last4=Oporto |first4=J. |last5=Brito |first5=J. L. |title=Southern Right whale dolphins, Lissodelphis peronii off the Pacific coast of South America |journal=Mammalian Biology - Zeitschrift fur Saugetierkunde |date=1991 |volume=56 |pages=284-295 |url=https://www.academia.edu/18654267/Southern_right_whale_dolphins_Lissodelphis_peronii_off_the_Pacific_coast_of_South_America}}</ref><ref name=CiteJefferson /><ref name=CiteNewcomer /> The precise boundary of their range has not been estimated or closely studied but the southern limit of the species appears to be bounded by the [[Antarctic Convergence]] while the northern limit seems bounded by the Tropical Convergence although rare sightings beyond these limits have been recorded.<ref name=CiteWaer1991 /> Most sightings of the southern right whale dolphins occur in offshore and deep waters, with temperatures ranging between 1 and 20°C. In regions where deep waters approach the coast and in [[upwelling]] areas, they have occasionally been observed near shore.<ref name=CiteJefferson /><ref name=CiteBarrie />
They have a streamlined body, a short, defined beak, no visible teeth, and a single blowhole. They are black and white in colour, with white undersides. No dorsal fin is present. They are fast, active swimmers. Newborn calves are about {{Convert|80|-|100|cm|abbr=on}} in length. Adults are between {{Convert|1.8|and|2.9|m|abbr=on}}. Females tend to be slightly longer than males. Adults weigh {{Convert|60|-|100|kg|abbr=on}}. They eat fish, squid, and octopus.


===Behaviour===
===South-America===
The species is known to be abundant along the western coasts of South America, ranging from [[Cape Horn]] to [[Arica]] (18°28’S), with the northernmost record at 12°30’S near [[Pucusana]] (northern Peru). Although the southern right whale dolphin is considered abundant, only few confirmed records of the species in the Eastern South Pacific exist.<ref name=CiteWaer1991 /><ref name=CiteAguayo>{{cite journal |last1=Aguayo-Lobo |first1=A. |last2=Torres Navarro |first2=D. |last3=Acevedo Ramírez |first3=J. |title=Los Mamíferos Marinos de Chile: 1. Cetacea = Marine Mammals of Chile: 1. Cetacea |journal=Serie Científica. Instituto Antártico Chileno |date=1998 |volume=48 |pages=19-159 |url=http://www.vliz.be/en/imis?module=ref&refid=213078 |issn=0073-9871}}</ref>

Preliminary boat surveys and stranding and fishery records suggest that southern right whale dolphins may be one of the most common species of cetacean in northern Chile. The range extends until {{Convert|170|km|abbr=on}} offshore north of 40°S and {{Convert|250|km|abbr=on}} off the southern coast of Chile and it has been suggested that at least a part of this Chilean population migrates northbound in the austral winter and spring, when the coastal component of the cold [[Humboldt Current]] and cool coastal upwelling are strongest.<ref name=CiteWaer1991 /><ref name=CiteJefferson /> An extension of the range to the North, associated to cold-water currents and food availability, has also been observed in Brazil, where a stranded individual was found in 1995 in an area where the warm [[Brazil Current]] meets the cold [[Falkland Current|Malvinas Current]].<ref name=CiteMartuscelli>{{cite journal |last1=Martuscelli |first1=P. |last2=Olmos |first2=F. |last3=Silva e Silva |first3=R. |last4=Mazzarella |first4=I.P. |last5=Pino |first5=F.V. |last6=Raduan |first6=E.N. |title=Cetaceans of São Paulo, Southeastern Brazil |journal=Mammalia |date=1996 |volume=60 |issue=1 |pages=125-139 |doi=10.1515/mamm.1996.60.1.125 }}</ref>

In 2018, two groups were sighted in the western area of the [[Magellan Strait]] in Chile. It was unclear through which route and why they entered the Magellan Strait but these were the first sightings of live southern right whales dolphins in this shallow area.<ref name=CitePinto>{{cite journal |last1=Pinto-Torres |first1=Marco |last2=Acevedo |first2=Jorge |last3=Mora |first3=Carla |last4=Iglesias |first4=Eva |last5=Bravo-Gómez |first5=Daniel |last6=Martínez |first6=Francisco |title=Sighting of southern right whale dolphin (Lissodelphis peronii) in the Magellan Strait, Chile |journal=Polar Biology |date=2019 |volume=42 |pp=633-638 |doi=10.1007/s00300-018-02446-4 |url=https://link.springer.com/article/10.1007%2Fs00300-019-02483-7 |accessdate=25 January 2020}}</ref> A few reports of solitary stranded specimens in exterior channels south of 40°S and the Beagle Channel have also shown their occurrence inside shallow channel systems.<ref name=CiteGoodall>{{cite journal |last1=Goodall |first1=Rae |title=Report on the small cetaceans stranded on the coasts of Tierra del Fuego |journal=Sci. Rep. Whales Res. Inst |date=1978 |volume=30 |pages=197-230 |url=https://scholar.google.com/scholar_lookup?title=Report%20on%20the%20small%20cetaceans%20stranded%20on%20the%20coasts%20of%20Tierra%20del%20Fuego&author=R.%20Goodall&journal=Sci%20Rep%20Whales%20Res%20Inst&volume=30&pages=197-230&publication_year=1978}}</ref><ref name=CiteGibbons>{{cite journal |last1=Gibbons |first1=J |last2=Gazitua |first2=F |last3=Venegas |first3=C |title=Cetacean in the Strait of Magellan and Otway, skyring and almirantazgo sounds |journal=An Inst de la Patagonia Punta Arenas |date=2000 |volume=28 |pages=107-118 |url=https://scholar.google.com/scholar_lookup?title=Cetacean%20in%20the%20Strait%20of%20Magellan%20and%20Otway%2C%20skyring%20and%20almirantazgo%20sounds&journal=An%20Inst%20de%20la%20Patagonia%20Punta%20Arenas%20%28Chile%29&volume=28&pages=107-118&publication_year=2000&author=Gibbons%2CJ&author=Gazitua%2CF&author=Venegas%2CC}}</ref> It has been hypothesized they may enter these channels accidentally or because of poor health.<ref name=CiteWaer1991 /> In the past, a high number of stranded southern right whale dolphins were reported on beaches of north-central chile, most of which were discarded animals by-caught In fishing nets. An increase in strandings is possibly due to the developing swordfish [[Gillnetting|gillnet fishery]] off northern Chile.<ref name=CiteWaer1991 />

The waters of the [[Patagonian Shelf|Patagonian continental shelf]] of Argentina harbor a high diversity of cetaceans, including southern right whale dolphins. They are known to occur in cold waters off [[Santa Cruz Province, Argentina|Santa Cruz Province]], the [[Falkland Islands]],<ref name=CiteLesson>{{cite journal |last1=Lesson |first1=R. P. |title=Indication de quelques Cétacés nouveaux observés dans le Voyage atour du monde de la Corvette La Coquille |journal=Bulletin des Sciences Naturelles et de Géologie |date=1826 |volume=7 |pages=373-374}}</ref> as well as off [[Tierra del Fuego]].<ref name=CiteGoodall /> Sightings in coastal areas are rare but exist in [[Mar de Plata]]<ref>{{cite journal |last1=Gallardo |first1=A. |title=El delfín Lagenorhynchus Fitzroyi (Waterhouse) Flower, capturado en Mar del Plata |journal=Anales Museo Nacional Historia Natural. Buenos Aires |date=1912 |volume=23 |pages=391-397}}</ref> and in [[Golfo Nuevo]], where three southern right whale dolphins were observed once during the summer of 1992.<ref name=CiteYazdi />

===Africa===
In Southern Africa, the range is associated with cold currents up the western and southern coasts, ranging northwards as far as about 23°S due to the cold counter clockwise [[Benguela Current]]. The species has been found to occur year-round in a localized key area on the southwestern coast of Namibia, in [[Lüderitz]], linked to the strong Lüderitz upwelling cell area and high productivity waters.<ref name=CiteBarrie /><ref name=CiteNewcomer /> These animals may occasionally extend their range into South African waters although more sampling effort is needed to support this. Just one confirmed sighting of the species exists from the South African coast, just south of the Orange River. Southern right whale dolphins have also been observed in waters around [[Marion Island]].<ref name=CiteCruickshank /><ref name=CiteBarrie /><ref name=CitePlon>{{cite journal |last1=Plön |first1=Stephanie |last2=Preston-Whyte |first2=Fiona |last3=Relton |first3=Claire |title=A conservation assessment of Lissodelphis peronii. In Child MF, Roxburgh L, Do Linh San E, Raimondo D, Davies-Mostert HT, editors. The Red List of Mammals of South Africa, Swaziland and Lesotho. South African National Biodiversity Institute and Endangered Wildlife Trust, South Africa |date=2016 |url=https://www.researchgate.net/publication/311677802_Plon_S_Preston-Whyte_F_Relton_C_2016_A_conservation_assessment_of_Lissodelphis_peronii_In_Child_MF_Roxburgh_L_Do_Linh_San_E_Raimondo_D_Davies-Mostert_HT_editors_The_Red_List_of_Mammals_of_South_Africa}}</ref>

===New Zealand and Australia===
The species has been observed in Australian waters since 1802, although only few actual records exist since then.<ref name=CiteClarke>{{cite journal |last1=Clarke |first1=Rohan H. |title=First record of the southern right whale dolphin Lissodelphis Peronii (Lacepede, 1804) (Odonoceti : Delphinidae), from waters off South Australia |journal=Transactions of the Royal Society of South Australia |date=2000 |volume=124 |issue=2 |pages=177-178 |url=https://www.researchgate.net/publication/299177973_First_record_of_the_southern_right_whale_dolphin_Lissodelphis_Peronii_Lacepede_1804_Odonoceti_Delphinidae_from_waters_off_South_Australia}}</ref> They are found off southern continental Australia including sightings south and southwestward of [[Tasmania]], in the [[Great Australian Bight]] and off south-western Australia.<ref name=CiteBannister>{{cite book |last1=Bannister |first1=J. L. |last2=Kemper |first2=C. M. |last3=Warneke |first3=R. M. |title=The Action Plan for Australian Cetaceans |date=1996 |publisher=Australian Nature Conservation Agency |location=Canberra |isbn=0642213887 |url=http://www.environment.gov.au/resource/action-plan-australian-cetaceans}}</ref> The species has also many times been observed at sea to the southeast of New Zealand.<ref name=CiteRoss>{{cite report|last1=Ross |first1=Graham J. B. |title=Review of the conservation status of Australia's smaller whales and dolphins |date=2006 |url=https://environment.gov.au/resource/review-conservation-status-australias-smaller-whales-and-dolphins |publisher=Australian Government - Department of the Environment and Heritage}}</ref> No key localities are known from the coast of Australia, although more survey effort could result in the identification of these localities, similar to the known key area off the west coast of Namibia.<ref name=CiteBarrie>{{cite journal |last1=Rose |first1=Barrie |last2=Payne |first2=Andrew I. L. |title=Occurrence and behavior of the southern right whale dolphin Lissodelphis peronii off Namibia |journal=Marine Mammal Science |date=1991 |volume=7 |issue=1 |pages=25-34 |url=https://doi.org/10.1111/j.1748-7692.1991.tb00547.x}}</ref><ref name="SPRAT">{{cite web|url=http://www.environment.gov.au/cgi-bin/sprat/public/publicspecies.pl?taxon_id=44|title=Lissodelphis peronii|work=Species Profile and Threats Database|publisher=Department of the Environment, Water, Heritage and the Arts, Canberra.|accessdate=2020-01-30}}</ref>

Few stranded individuals have been documented in Australian waters.<ref name=CiteBaker /> A single mass stranding of three southern right whale dolphins was recorded in New Zealand in 1952.<ref>{{cite journal |last1=Fraser |first1=F. C. |title=The southern right whale dolphin, Lissodelphis peronii (Lacépède) external characteristics and distribution |journal=Bull. Brit. Mus. (Nat. Hist.) Zool. |date=1955 |volume=2 |issue=2 |pages=339-346}}</ref> In December 2019, a dolphin washed up on a beach at [[Port Fairy, Victoria]], with the deceased animal being assessed by state authorities, researchers and local [[Australian Aborigine]] elders. Another dolphin washed up in January 2020 and was photographed, but the dead animal washed back off the beach. The dual strandings were described as ‘very unusual’ by authorities.<ref>{{cite web |last1=Johnson |first1=Sian |title=Southern right whale dolphins wash up on Port Fairy's East Beach in south-west Victoria |url=https://www.abc.net.au/news/2020-01-15/southern-right-whale-dolphins-wash-up-at-port-fairy-victoria/11866010 |website=ABC South West Vic |accessdate=2020-01-25}}</ref>

==Behavior==

===Social===
[[File:Anim0796 - Flickr - NOAA Photo Library.jpg|thumb|Southern right whale dolphins porpoising]]
[[File:Anim0796 - Flickr - NOAA Photo Library.jpg|thumb|Southern right whale dolphins porpoising]]
Southern right whale dolphins are very graceful and often move by leaping out of the water continuously. When they swim slowly, they expose only a small area of the head and back when they surface to breathe. Breaching, belly-flopping, side-slapping, and lob-tailing (slapping the flukes on the water surface) have been witnessed. They typically live in groups of two to 100. Some groups are more nervous than others, and swim away from boats, whereas others approach and possibly bow-ride. This tendency to bow-ride worked against them in the 19th century, as it allowed whalers to harpoon them from the bow and use them as food. Southern right whale dolphins are often seen in the company of [[hourglass dolphin]]s.


Southern right whale dolphins are gregarious and have been documented in schools ranging from 4 to more than 1000 individuals.<ref name=CiteGaskin>{{cite journal |last1=Gaskin |first1=D. E. |title=Distribution of Delphinidae (Cetacea) in relation to sea surface temperatures off Eastern and Southern New Zealand |journal=New Zealand Journal of Marine and Freshwater Research |date=1968 |volume=2 |issue=3 |pages=527–534 |doi=10.1080/00288330.1968.9515253 |url=https://doi.org/10.1080/00288330.1968.9515253}}</ref> Mean group size estimates differ and range between 52 and 368 off northern Chile,<ref name=CiteWaer1991 /><ref name="SPRAT" /><ref name=CiteADW>{{cite web |last1=Stanley |first1=E. |last2=Podzikowski |first2=L. |title="Lissodelphis peronii" (On-line) |url=https://animaldiversity.org/accounts/Lissodelphis_peronii/ |website=Animal Diversity Web |accessdate=29 January 2020}}</ref> however, they typically live in groups of 100-200 individuals.<ref>{{cite book |last1=Shirihai |first1=H. |last2=Jarrett |first2=B. |title=Whales, dolphins, and seals : a field guide to the marine mammals of the world |date=2006 |publisher=Bloomsbury Publishing |location=London |isbn=9780713670370 |pages=225-227}}</ref> Pods of just a few animals have also been observed, often associated with other cetacean species. [[Dusky dolphin]] (''Lagenorhynchus obscurus'') associations appear common in the Southern Atlantic and have occasionally been reported in New-Zealand, off Southwest Africa and along the coast of Southern Chile.<ref name=CiteWaerebeek>{{cite thesis|last1=Van Waerebeek |first1=K. C. C. |title=Population identity and general biology of the dusky dolphin Lagenorhynchus obscurus (Gray, 1828) in the Southeast Pacific |date=1992 |publisher=PhD Thesis. Institute for Taxonomic Zoology |location=University of Amsterdam}}</ref><ref name=CiteBarrie /><ref name=CiteYin>{{cite thesis|last1=Yin |first1=Suzanne E. |title=Movement patterns, behaviors, and whistle sounds of dolphin groups off Kaikoura, New Zealand |journal=Master's thesis, Texas A&M University |date=1999 |url=http://hdl.handle.net/1969.1/ETD-TAMU-1999-THESIS-Y46.}}</ref> They have been observed to intermix freely with [[pilot whales]] (''Globicephala spp.'') and in Chile, associations with [[common dolphins]] (''Delphinus delphis'') have been reported.<ref name=CiteJefferson /><ref name=CiteWaer1991>{{cite journal |last1=Van Waerebeek |first1=K. |last2=Canto |first2=J. |last3=Gonzalez |first3=J. |last4=Oporto |first4=J. |last5=Brito |first5=J. L. |title=Southern Right whale dolphins, Lissodelphis peronii off the Pacific coast of South America |journal=Mammalian Biology - Zeitschrift fur Saugetierkunde |date=1991 |volume=56 |pages=284-295 |url=https://www.academia.edu/18654267/Southern_right_whale_dolphins_Lissodelphis_peronii_off_the_Pacific_coast_of_South_America}}</ref> Along its range it has also occasionally been sighted with [[Hourglass Dolphin|hourglass dolphins]] (''L. Cruciger''), [[Common Bottlenose Dolphin|common bottlenose dolphins]] (''Tursiops truncatus'') and [[fin whales]] (''Balaenoptera physalus'').<ref name=CiteBarrie /><ref name=CiteJefferson />
In December 2019, a dolphin washed up on a beach at [[Port Fairy, Victoria]], with the carcase being assessed by state authorities and local [[Australian Aborigine]] elders. Another dolphin washed up in January 2020 and was photographed, but the carcase washed back off the beach. The dual strandings were described as ‘very unusual’ by authorities.<ref name="2020-01-15_ABC">[https://www.abc.net.au/news/2020-01-15/southern-right-whale-dolphins-wash-up-at-port-fairy-victoria/11866010 'Very unusual': Rare deep-sea dolphins wash up on Victorian beach], Sian Johnson, [[ABC News Online]], 2020-01-15</ref>

Four basic herd configuration types have been reported and conform to the types described for the northern right whale dolphin: Densely packed schools, without identifiable subgroups; herds of scattered subgroups of various sizes; V-shaped herds; and herds in ‘’chorus line’’ formation.<ref name=CiteCruickshank>{{cite journal |last1=Cruickshank |first1=R. A. |last2=Brown |first2=S. G. |title=Recent observations and some historical records of southern right-whale dolphins Lissodelphis peronii |journal=Fisheries Bulletin of South Africa |date=1981 |volume=15 |pages=109-121}}</ref><ref name=CiteLeatherwood1>{{cite book |last1=Leatherwood |first1=S. |last2=Walker |first2=W. A. |title=The Northern Right Whale Dolphin Lissodelphis borealis Peale in the Eastern North Pacific. In: Winn H.E., Olla B.L. (eds) Behavior of Marine Animals, Volume 3: Cetaceans |date=1979 |publisher=Plenum Press |location=New York |isbn=978-1-4684-2985-5 |page=438}}</ref> Their movement is very graceful and they often move by leaping out of the water continuously. When they swim slowly, they expose only a small area of the head and back while surfacing to breath. When traveling at higher speeds they have been observed to either (1) swim just below the surface, surfacing briefly to breath and then submerge or (2) swim rapidly at the surface, performing low-angle leaps covering much surface distance. Breaching, belly-flopping, side-slapping, and lob-tailing (slapping the flukes on the water surface) have been witnessed.<ref name=CiteNewcomer /> Some groups will avoid boats, whereas others approach and possibly bow-ride. Few direct speed measurements at sea exist but swimming speed has been reported to be {{Convert|22|km/h|abbr=on}}.<ref name=CiteCruickshank /><ref name=CiteBarrie />

===Foraging===
Southern right whale dolphins prey on an undetermined range of fish, but it has been suggested they prey primarily on mesopelagic fish and squid, and may dive to depths in excess of {{Convert|200|m|abbr=on}} in search of food.<ref name=CiteBaker>{{cite book |last1=Baker |first1=A. N. |title=The Southern Right Whale dolphin, Lissodelphis peroni (Lacépède) in Australasian water |date=1981 |publisher=National Museum of New Zealand |location=Wellington |pages=17-34 |edition=2 |url=https://www.worldcat.org/title/southern-right-whale-dolphin-lissodelphis-peroni-lacepede-in-australasian-water/oclc/889342917}}</ref><ref name=CiteJefferson /> However, little is known of their particular habits, and it is unknown whether they generally search for their food at these greater depths or near the surface.<ref name="SPRAT" /> Based on stomach contents, epipelagic coastal food habits, meso-pelagic or both, epi- and mesopelagic feeding were suggested for southern right whale dolphins.<ref name=CiteTORRES /><ref name=CiteBaker /><ref>{{cite journal |last1=Crovetto |first1=A. |last2=Lamilla |first2=J. |last3=Pequeño |first3=G. |title=Lissodelphis peronii, Lacépède 1804 (Delphinidae, Cetacea) within the stomach contents of a sleeping shark, Somniosus cf. pacificus, Bigelow and Schroeder 1944, in Chilean waters |journal=Marine Mammal Science |date=1992 |volume=8 |issue=3 |pages=312-314}}</ref> Geographical variability in prey species has been observed by comparing stomach contents of animals from central Chile and New Zealand.<ref name=CiteTORRES>{{cite journal |last1=Torres |first1=Daniel N. |last2=Aguayo |first2=Anelio L. |title=Habitos alimentarios de Lissodelphis peronii (Lacepede, 1804) en Chile Central (Cetacea: Delphinidae) |journal=Rev. Biol. Mar. Dep. Oceanol. Univ. Chile |date=1979 |volume=16 |issue=3 |pages=221-224 |url=https://revbiolmar.uv.cl/escaneados/163-221.pdf}}</ref><ref name=CiteWaer1991 /><ref name=CitePinto />.

The species itself is presumably occasionally predated upon by larger sharks and [[killer whale]]s (''Orcinus orca'') however, other predators might exist. In 1983, an intact dolphin measuring {{Convert|0.86|m|abbr=on}} was found in the stomach of a {{Convert|1.7|m|abbr=on}} [[Patagonian toothfish]] (''Dissostichus eleginoides'') taken off central Chile, and in 1990, a foetus was discovered inside a [[sleeper shark]] (''Somniosus'' cf. ''pacificus'').<ref name=CiteWaer1991 /><ref name=CiteJefferson />

==Threats==
Overall, clear evidence of the impact of potential threats on the species are sparse. Southern right whale dolphins were taken by whaling operations of the 19th century, primarily for their meat.<ref name=CiteCruickshank /> In the past they have been infrequently caught off the coasts of Peru and Chile, where their meat and blubber were used as food and crab bait.<ref name=CiteTORRES /><ref name=CiteJefferson /><ref name=CiteNewcomer /> High levels of bycaught animals have been recorded in the [[Swordfish]] (‘’Xiphias gladius’’) [[drift netting|driftnet]] fishery in northern Chile, which started in the early 1980s,<ref>{{cite journal |last1=Reyes |first1=J. C. |last2=Oporto |first2=J.A. |title=Gillnet fisheries and cetaceans in the southeast Pacific |journal=Reports of the International Whaling Commission |date=1994 |volume=15 |pages=467-474 |url=https://scholar.google.be/scholar?hl=en&as_sdt=0%2C5&q=Reyes%2C+J.+C.+and+Oporto%2C+J.+A.+1994.+Gillnet+fisheries+and+cetaceans+in+the+southeast+Pacific.+Reports+of+the+International+Whaling+Commission+15%3A+467-474.&btnG=}}</ref> and to a lesser extent, the species has also been incidentally caught in driftnets along the coast of Peru.<ref name=CiteJefferson93>{{cite book |last1=Jefferson |first1=Thomas A. |last2=Leatherwood |first2=Stephen |last3=Webber |first3=Marc A. |title=Marine mammals of the world |date=1993 |publisher=Food and Agriculture Organization of the United Nations |location=Rome |isbn=92-5-103292-0 |url=https://www.worldcat.org/title/marine-mammals-of-the-world/oclc/30643250 |accessdate=25 January 2020}}</ref>

Large numbers of ''L. peronii'' are sometimes taken by [[gillnet]]ting and [[longline fishing]] in oceans off the southern coast of Australia.<ref name="SPRAT" /> Off the west coast of southern Africa, no evidence exists of bycatch in gillnet fisheries, but there may be competition for forage resources with pelagic [[trawling|trawl fisheries]] due to its pelagic distribution and squid based diet.<ref name=CitePlon /> The direct and indirect impacts of global climate change on the Southern Right Whale Dolphin are largely unknown, but could have a cascading effect on the movement and feeding ecology. Seismic activity, for oil and gas, might also be a minor threat,<ref>{{cite journal |last1=Learmonth |first1=J. A. |last2=Macleod |first2=C. D. |last3=Santos Vazquez |first3=M. B. |last4=Pierce |first4=G. J. |last5=Crick |first5=H. Q. P. |last6=Robinson |first6=R. A. |title=Potential effects of climate change on marine mammals |journal=Oceanography and Marine Biology: An Annual Review |date=2006 |volume=44 |pages=431-464 |url=https://books.google.be/books?hl=en&lr=&id=R7-TfdYeLEgC&oi=fnd&pg=PA431&dq=Learmonth+JA,+MacLeod+CD,+Santos+MB,+Pierce+GJ,+Crick+HQP,+Robinson+RA.+2006.+Potential+effects+of+climate+change+on+marine+mammals.+Oceanography+and+Marine+Biology+44:431.&ots=dv0g8d8nJm&sig=HSAgBwGyFtq-liaCzbpSXmJBf80#v=onepage&q=Learmonth%20JA%2C%20MacLeod%20CD%2C%20Santos%20MB%2C%20Pierce%20GJ%2C%20Crick%20HQP%2C%20Robinson%20RA.%202006.%20Potential%20effects%20of%20climate%20change%20on%20marine%20mammals.%20Oceanography%20and%20Marine%20Biology%2044%3A431.&f=false}}</ref><ref>{{cite journal |last1=Kaschner |first1=Kristin |last2=Tittensor |first2=Derek P. |last3=Ready |first3=Jonathan |last4=Gerrodette |first4=Tim |last5=Worm |first5=Boris |title=Current and future patterns of global marine mammal biodiversity. |journal=PloS one |date=2011 |volume=6 |issue=5 |doi=10.1371/journal.pone.0019653 |pmid=21625431 |url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3100303/}}</ref><ref name=CitePlon />

==Taxonomy==
The species was first published by [[Bernard Germain de Lacépède]] in 1804. The southern right whale dolphins together with the northern right whale dolphins are the only members of the genus ''Lissodelphis'', which name is derived from the Greek, with ''lisso'' meaning smooth, and ''delphis'' meaning dolphin. Recent classifications have placed ''Lissodelphis'' within the [[Delphinidae]], the oceanic dolphin family of [[cetacean]]s.<ref name="ITIS" />. The specific epithet ''peronii'' commemorates [[François Péron]], a French naturalist who saw the species near [[Tasmania]] during an expedition in 1802.<ref name=CiteLeatherwood>{{cite book |last1=Leatherwood |first1=S. |last2=Reeves |first2=R.R. |title=The Sierra Club handbook of whales and dolphins |date=1983 |publisher=Sierra Club Books |location=San Francisco}}</ref> Although some doubts remain on the validity of these two species, most authors currently retain them as separate species.<ref name=CiteJefferson /><ref name=EOMM />


Both species in the genus are referred to by the name "right whale dolphin", a name derived from the [[right whales]] (''Eubalaena'') which also lack a dorsal fin.<ref name="SPRAT" /> Other [[common name]]s for the southern right whale dolphin include: whitebellied right whale dolphin, southern right whale porpoise, mealy-mouthed porpoise, ''tunina (=tonina) sin aleta'' (Spanish), ''delfin (=delphin) liso austral'' (Spanish), ''minami semi-iruka'' (Japanese), ''dauphin de Peron'' (French), ''dauphin aptère austral'' (French), ''dauphin aptère austral'' (French), ''yuzhnyi kitovidnyi delfin'' (Russian), ''südlichen Glattdelphins'' (German), and ''zuidelijke gladde dolfijn'' (Dutch).<ref name=CiteNewcomer /> ''dauphin aptère austral'' (French), ''yuzhnyi kitovidnyi delfin'' (Russian), ''südlichen Glattdelphins'' (German), and ''zuidelijke gladde dolfijn'' (Dutch).<ref name=CiteNewcomer />
==Conservation==
The southern right whale dolphin is included in the Memorandum of Understanding Concerning the Conservation of the Manatee and Small Cetaceans of Western Africa and Macaronesia ([[West African Aquatic Mammals Memorandum of Understanding|Western African Aquatic Mammals MoU]])<ref>[http://www.cms.int/species/waam/index.htm Memorandum of Understanding Concerning the Conservation of the Manatee and Small Cetaceans of Western Africa and Macaronesia]</ref> and the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region ([[Pacific Islands Cetaceans Memorandum of Understanding|Pacific Cetaceans MoU]]).<ref>[http://www.pacificcetaceans.org/ Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region]</ref>


==See also==
==See also==

Revision as of 22:31, 1 March 2020

Southern right whale dolphin
A French drawing from 1847
Size compared to an average human
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Infraorder: Cetacea
Family: Delphinidae
Genus: Lissodelphis
Species:
L. peronii
Binomial name
Lissodelphis peronii
Range map

The southern right whale dolphin (Lissodelphis peronii) is a small and slender species of mammal, found in cool waters of the Southern Hemisphere. It is one of two species of right whale dolphin; Lissodelphis, a genus characterized by the lack of a dorsal fin. The other species, the northern right whale dolphin (Lissodelphis borealis), is found in deep oceans of the Northern Hemisphere and has a different pigmentation pattern than the southern right whale dolphin.

Description

Southern right whale dolphins can be easily distinguished from other cetacean species within their range as they are the only dolphins without dorsal fins in the Southern Hemisphere. They have streamlined and graceful bodies, a single blowhole and a short and defined beak, possessing between 39 and 50 teeth in each row of both jaws.[3][4]

A sharp dividing line separates the black dorsal part from the white ventral part of the body, running from the tail stock forward, dipping down to the flipper insertion and sweeping back up, below the eyes, to cross the melon between the blowhole and snout crease.[3][5][4] Younger individuals can be grey/brownish dorsally but develop adult coloration within the first year.[6][3][4] The flippers of the southern right whale dolphins are small, recurved, predominantly white and located about one-quarter of the way back from the snout tip. Their flukes are small, have a white underside and dark grey upper side, with a notch in the middle and concave trailing edges.[3]

Variability in the size of these black and white areas exists.[7][8] More extensive anomalous pigmentation has been observed, with records of pure all-white individuals,[9][10] as well as melanistic (all-black) individuals.[11][12] In 1998, a potential hybrid of a southern right whale dolphin and a Dusky dolphin (Lagenorhynchus obscurus) was observed and subsequently described in 2002. This animal showed intermediate morphological features between the two species.[5]

Newborn calves measure around 86 cm (34 in) in length and weigh around 5 kg (11 lb), while adults range between 2.18 and 2.5 m (7 ft 2 in and 8 ft 2 in) and weight between 60–100 kg (130–220 lb) on average.[3][11][4]. The maximum weight for southern Right Whale Dolphins is 116 kg, with maximum lengths reaching 297 cm (117 in) in males and 230 cm (91 in) in females but few specimens have been examined and it is expected they grow larger.[7] On average, males tend to grow slightly larger than females. Little is known of this species’ reproductive biology. Research suggests that males reach sexual maturity at lengths between 212–220 cm (83–87 in) and females between 206–212 cm (81–83 in).[3]

Population status

There are no current global abundance and mortality estimates of the species although it is considered a fairly common and abundant species along its range,[3] particularly in Chile[13]. The very low sighting rate is most likely caused by a lack of sampling effort and due to the difficulties of sighting the animals in their offshore habitat.

Geographic range/distribution

Southern right whale dolphins have a circumpolar distribution across the Southern Hemisphere, generally occurring in cool temperate to Sub-Antarctic waters between 30°S and 65°S.[13][3][11] The precise boundary of their range has not been estimated or closely studied but the southern limit of the species appears to be bounded by the Antarctic Convergence while the northern limit seems bounded by the Tropical Convergence although rare sightings beyond these limits have been recorded.[13] Most sightings of the southern right whale dolphins occur in offshore and deep waters, with temperatures ranging between 1 and 20°C. In regions where deep waters approach the coast and in upwelling areas, they have occasionally been observed near shore.[3][8]

South-America

The species is known to be abundant along the western coasts of South America, ranging from Cape Horn to Arica (18°28’S), with the northernmost record at 12°30’S near Pucusana (northern Peru). Although the southern right whale dolphin is considered abundant, only few confirmed records of the species in the Eastern South Pacific exist.[13][14]

Preliminary boat surveys and stranding and fishery records suggest that southern right whale dolphins may be one of the most common species of cetacean in northern Chile. The range extends until 170 km (110 mi) offshore north of 40°S and 250 km (160 mi) off the southern coast of Chile and it has been suggested that at least a part of this Chilean population migrates northbound in the austral winter and spring, when the coastal component of the cold Humboldt Current and cool coastal upwelling are strongest.[13][3] An extension of the range to the North, associated to cold-water currents and food availability, has also been observed in Brazil, where a stranded individual was found in 1995 in an area where the warm Brazil Current meets the cold Malvinas Current.[15]

In 2018, two groups were sighted in the western area of the Magellan Strait in Chile. It was unclear through which route and why they entered the Magellan Strait but these were the first sightings of live southern right whales dolphins in this shallow area.[16] A few reports of solitary stranded specimens in exterior channels south of 40°S and the Beagle Channel have also shown their occurrence inside shallow channel systems.[17][18] It has been hypothesized they may enter these channels accidentally or because of poor health.[13] In the past, a high number of stranded southern right whale dolphins were reported on beaches of north-central chile, most of which were discarded animals by-caught In fishing nets. An increase in strandings is possibly due to the developing swordfish gillnet fishery off northern Chile.[13]

The waters of the Patagonian continental shelf of Argentina harbor a high diversity of cetaceans, including southern right whale dolphins. They are known to occur in cold waters off Santa Cruz Province, the Falkland Islands,[19] as well as off Tierra del Fuego.[17] Sightings in coastal areas are rare but exist in Mar de Plata[20] and in Golfo Nuevo, where three southern right whale dolphins were observed once during the summer of 1992.[5]

Africa

In Southern Africa, the range is associated with cold currents up the western and southern coasts, ranging northwards as far as about 23°S due to the cold counter clockwise Benguela Current. The species has been found to occur year-round in a localized key area on the southwestern coast of Namibia, in Lüderitz, linked to the strong Lüderitz upwelling cell area and high productivity waters.[8][11] These animals may occasionally extend their range into South African waters although more sampling effort is needed to support this. Just one confirmed sighting of the species exists from the South African coast, just south of the Orange River. Southern right whale dolphins have also been observed in waters around Marion Island.[6][8][21]

New Zealand and Australia

The species has been observed in Australian waters since 1802, although only few actual records exist since then.[22] They are found off southern continental Australia including sightings south and southwestward of Tasmania, in the Great Australian Bight and off south-western Australia.[23] The species has also many times been observed at sea to the southeast of New Zealand.[24] No key localities are known from the coast of Australia, although more survey effort could result in the identification of these localities, similar to the known key area off the west coast of Namibia.[8][25]

Few stranded individuals have been documented in Australian waters.[7] A single mass stranding of three southern right whale dolphins was recorded in New Zealand in 1952.[26] In December 2019, a dolphin washed up on a beach at Port Fairy, Victoria, with the deceased animal being assessed by state authorities, researchers and local Australian Aborigine elders. Another dolphin washed up in January 2020 and was photographed, but the dead animal washed back off the beach. The dual strandings were described as ‘very unusual’ by authorities.[27]

Behavior

Social

Southern right whale dolphins porpoising

Southern right whale dolphins are gregarious and have been documented in schools ranging from 4 to more than 1000 individuals.[28] Mean group size estimates differ and range between 52 and 368 off northern Chile,[13][25][29] however, they typically live in groups of 100-200 individuals.[30] Pods of just a few animals have also been observed, often associated with other cetacean species. Dusky dolphin (Lagenorhynchus obscurus) associations appear common in the Southern Atlantic and have occasionally been reported in New-Zealand, off Southwest Africa and along the coast of Southern Chile.[31][8][32] They have been observed to intermix freely with pilot whales (Globicephala spp.) and in Chile, associations with common dolphins (Delphinus delphis) have been reported.[3][13] Along its range it has also occasionally been sighted with hourglass dolphins (L. Cruciger), common bottlenose dolphins (Tursiops truncatus) and fin whales (Balaenoptera physalus).[8][3]

Four basic herd configuration types have been reported and conform to the types described for the northern right whale dolphin: Densely packed schools, without identifiable subgroups; herds of scattered subgroups of various sizes; V-shaped herds; and herds in ‘’chorus line’’ formation.[6][33] Their movement is very graceful and they often move by leaping out of the water continuously. When they swim slowly, they expose only a small area of the head and back while surfacing to breath. When traveling at higher speeds they have been observed to either (1) swim just below the surface, surfacing briefly to breath and then submerge or (2) swim rapidly at the surface, performing low-angle leaps covering much surface distance. Breaching, belly-flopping, side-slapping, and lob-tailing (slapping the flukes on the water surface) have been witnessed.[11] Some groups will avoid boats, whereas others approach and possibly bow-ride. Few direct speed measurements at sea exist but swimming speed has been reported to be 22 km/h (14 mph).[6][8]

Foraging

Southern right whale dolphins prey on an undetermined range of fish, but it has been suggested they prey primarily on mesopelagic fish and squid, and may dive to depths in excess of 200 m (660 ft) in search of food.[7][3] However, little is known of their particular habits, and it is unknown whether they generally search for their food at these greater depths or near the surface.[25] Based on stomach contents, epipelagic coastal food habits, meso-pelagic or both, epi- and mesopelagic feeding were suggested for southern right whale dolphins.[34][7][35] Geographical variability in prey species has been observed by comparing stomach contents of animals from central Chile and New Zealand.[34][13][16].

The species itself is presumably occasionally predated upon by larger sharks and killer whales (Orcinus orca) however, other predators might exist. In 1983, an intact dolphin measuring 0.86 m (2 ft 10 in) was found in the stomach of a 1.7 m (5 ft 7 in) Patagonian toothfish (Dissostichus eleginoides) taken off central Chile, and in 1990, a foetus was discovered inside a sleeper shark (Somniosus cf. pacificus).[13][3]

Threats

Overall, clear evidence of the impact of potential threats on the species are sparse. Southern right whale dolphins were taken by whaling operations of the 19th century, primarily for their meat.[6] In the past they have been infrequently caught off the coasts of Peru and Chile, where their meat and blubber were used as food and crab bait.[34][3][11] High levels of bycaught animals have been recorded in the Swordfish (‘’Xiphias gladius’’) driftnet fishery in northern Chile, which started in the early 1980s,[36] and to a lesser extent, the species has also been incidentally caught in driftnets along the coast of Peru.[37]

Large numbers of L. peronii are sometimes taken by gillnetting and longline fishing in oceans off the southern coast of Australia.[25] Off the west coast of southern Africa, no evidence exists of bycatch in gillnet fisheries, but there may be competition for forage resources with pelagic trawl fisheries due to its pelagic distribution and squid based diet.[21] The direct and indirect impacts of global climate change on the Southern Right Whale Dolphin are largely unknown, but could have a cascading effect on the movement and feeding ecology. Seismic activity, for oil and gas, might also be a minor threat,[38][39][21]

Taxonomy

The species was first published by Bernard Germain de Lacépède in 1804. The southern right whale dolphins together with the northern right whale dolphins are the only members of the genus Lissodelphis, which name is derived from the Greek, with lisso meaning smooth, and delphis meaning dolphin. Recent classifications have placed Lissodelphis within the Delphinidae, the oceanic dolphin family of cetaceans.[2]. The specific epithet peronii commemorates François Péron, a French naturalist who saw the species near Tasmania during an expedition in 1802.[40] Although some doubts remain on the validity of these two species, most authors currently retain them as separate species.[3][4]

Both species in the genus are referred to by the name "right whale dolphin", a name derived from the right whales (Eubalaena) which also lack a dorsal fin.[25] Other common names for the southern right whale dolphin include: whitebellied right whale dolphin, southern right whale porpoise, mealy-mouthed porpoise, tunina (=tonina) sin aleta (Spanish), delfin (=delphin) liso austral (Spanish), minami semi-iruka (Japanese), dauphin de Peron (French), dauphin aptère austral (French), dauphin aptère austral (French), yuzhnyi kitovidnyi delfin (Russian), südlichen Glattdelphins (German), and zuidelijke gladde dolfijn (Dutch).[11] dauphin aptère austral (French), yuzhnyi kitovidnyi delfin (Russian), südlichen Glattdelphins (German), and zuidelijke gladde dolfijn (Dutch).[11]

See also

References

  1. ^ Braulik, G. 2018. Lissodelphis peronii. The IUCN Red List of Threatened Species 2018: e.T12126A50362558. https://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T12126A50362558.en. Downloaded on 18 December 2018.
  2. ^ a b "Lissodelphis peronii (Lacépède, 1804)". Integrated Taxonomic Information System.
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