| Southern right whale[1] | |
|---|---|
 | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Artiodactyla |
| Suborder: | Whippomorpha |
| Infraorder: | Cetacea |
| Family: | Balaenidae |
| Genus: | Eubalaena |
| Species: | E. australis |
| Binomial name | |
| Eubalaena australis (Desmoulins, 1822) | |
 | |
| Range | |
| Synonyms[4] | |
| |
 | This article'slead sectionmay be too short to adequatelysummarize the key points. Please consider expanding the lead toprovide an accessible overview of all important aspects of the article.(December 2024) |
Thesouthern right whale (Eubalaena australis) is abaleen whale, one of three species classified asright whales belonging to the genusEubalaena. Southern right whales inhabit oceans south of the Equator, between the latitudes of 20° and 60° south.[5] In 2009 the global population was estimated to be approximately 13,600.[6]
Right whales were first classified in the genusBalaena in 1758 byCarl Linnaeus, who at the time considered all right whales (including the bowhead) to be a single species. In the 19th and 20th centuries the familyBalaenidae was the subject of great taxonometric debate. Authorities have repeatedly recategorised the three populations of right whale plus the bowhead whale, as one, two, three or four species, either in a single genus or in two separate genera. In the early whaling days, they were all thought to be a single species,Balaena mysticetus.[7]
The southern right whale was initially described asBalaena australis by Desmoulins in 1822. Eventually, it was recognised that bowheads and right whales were different, andJohn Edward Gray proposed the genusEubalaena for the right whale in 1864. Later, morphological factors such as differences in the skull shape of northern and southern right whales indicated at least two species of right whale—one in the Northern Hemisphere, the other in theSouthern Ocean.[7] As recently as 1998, Rice, in his comprehensive and otherwise authoritative classification,Marine mammals of the world: systematics and distribution, listed just two species:Balaena glacialis (all of the right whales) andBalaena mysticetus (the bowheads).[8]
In 2000, Rosenbaum et al. disagreed, based on data from their genetic study ofDNA samples from each of the whale populations. Genetic evidence now shows that the northern and southern populations of right whale have not interbred for between 3 million and 12 million years, confirming the southern right whale as a distinct species. The northern Pacific and Atlantic populations are also distinct, with the North Pacific right whale being more closely related to the southern right whale than to the North Atlantic right whale.[9] Genetic differences betweenE. japonica (North Pacific) andE. australis (South Pacific) are much smaller than other baleen whales represent among different ocean basins.[10]
It is believed that the right whale populations first split because of the joining of North and South America when thePanama isthmus formed. The rising temperatures at theequator then created a second split, into the northern and southern groups, preventing them from interbreeding.[11]
In 2002, the Scientific Committee of theInternational Whaling Commission (IWC) accepted Rosenbaum's findings, and recommended that theEubalaena nomenclature be retained for this genus.[12]
Thecladogram is a tool for visualising and comparing the evolutionary relationships betweentaxa. The point where a node branches off is analogous to an evolutionary branching – the diagram can be read left-to-right, much like a timeline. The following cladogram of the family Balaenidae serves to illustrate the current scientific consensus as to the relationships between the southern right whale and the other members of its family.
| Family Balaenidae | |||||||||||||||||||||
| |||||||||||||||||||||
| The right whale family, Balaenidae[9] |
Otherjunior synonyms forE. australis have includedB. antarctica (Lesson, 1828),B. antipodarum (Gray, 1843),Hunterus temminckii (Gray, 1864), andE. glacialis australis (Tomilin, 1962) (see side panel for more synonyms).[1][4]
Like other right whales, the southern right whale is readily distinguished from others by thecallosities on its head, a broad back without adorsal fin, and a long arching mouth that begins above the eye. Its skin is very dark grey or black, occasionally with some white patches on the belly. The right whale's callosities appear white due to large colonies of cyamids (whale lice). It is almost indistinguishable from the closely relatedNorth Atlantic and theNorth Pacific right whales, displaying only minor skull differences. It may have fewer callosities on its head than North Atlantic and more on its lower lips than the two northern species.[7][13] The biological functions of callosities are unclear, although protection against predators has been put forward as the primal role.[citation needed]
An adult female is 15 m (49 ft)[14] and can weigh up to 47 tonnes (46 long tons; 52 short tons),[14] with the larger records of 17.5–18 m (57–59 ft)[15][16] in length and 80 tonnes (79 long tons; 88 short tons)[17] or up to 90 tonnes (89 long tons; 99 short tons) in weight,[18] making them slightly smaller than other right whales in theNorthern Hemisphere.[19] The testicles of right whales are likely to be the largest of any animal, each weighing around 500 kg (1,100 lb). This suggests thatsperm competition is important in the mating process.[20]
The proportion and numbers of molten-coloured individuals are notable in this species compared with the other species in the Northern Hemisphere. Some whales remain white even after growing up.[21]
The median lifespan is around 73, with some individuals surviving to over 130.[22]
Like other right whales, they are rather active on the water surface and curious towards human vessels. Southern rights appear to be more active and tend to interact with humans more than the other two northern species.[citation needed] One behaviour unique to the southern right whale, known astail sailing, is that of using their elevated flukes to catch the wind, remaining in the same position for a considerable amount of time. It appears to be a form of play and is most commonly seen off the coast of Argentina and South Africa.[13] Some other species such ashumpback whales are also known to display. Right whales are often seen interacting with other cetaceans, especially humpback whales[23] anddolphins. There have been records of southern rights and humpbacks thought to be involved in mating activities offMozambique,[24] and alongBahia, Brazil.[25]
A female southern right whale was spotted off the coast of Western Australia accompanying a lone humpback whale calf, although the actual relationship of this pair is unclear.[26]
Southern right whales display strongmaternal fidelity to their calving grounds.[27][28] Calving females are known to return to calving grounds at 3-year intervals.[29] The most commonly observed calving interval is 3 years, but intervals can range from 2 to 21 years.[30][31] Calving takes place between June and November[32] in calving grounds between 20 and 30° S.[33]
In Australia, southern right whales have shown a preference for calving grounds along coastlines with high wave energy, such as theHead of the Bight. Here, the sound of breaking waves may mask the sound of the whales' presence, and so protect infants and calving cows from predators such askiller whales. Deep waters alongside shallower calving grounds may serve as training grounds for calves to build up their stamina ahead of migration.[34]
Females give birth to their first calf when they are between eight and ten years old.[35] A single calf is born after agestation period of one year, about 1 short ton (0.91 t) in weight and 4–6 m (13–20 ft) in length.[36] The calf usually remains with its mother during the first year of its life, during which time it will double in length.[5]
Southern right whales have been observed nursing unrelated orphans on occasions.[37]
Like right whales in other oceans, southern right whales feed almost exclusively onzooplankton, particularly krill.[5] They feed just beneath the water's surface, holding their mouths partly open and skimming water continuously while swimming. They strain the water out through their longbaleen plates to capture their prey. A southern right whale's baleen can measure up to 2.8 m (9 ft 2 in) long, and is made up of 220–260 baleen plates.[32]
The global population of southern right whales was estimated at 13,611 in 2009.[6] An estimate published byNational Geographic in October 2008 put the southern whale population at 10,000. A population estimate of 7,000 followed a March 1998IWC workshop. Researchers used population data from three surveys of adult females in the 1990s (Argentina, South Africa and Australia). They extrapolated to include the population of unsurveyed areas, and used known male-to-female and adult-to-calf ratios to estimate and include numbers of males and calves.[38] Recovery of the overall population size of the species is predicted to be at less than 50% of its pre-whaling state by 2100 due to heavier impacts of whaling and slower recovery rates.[39] Since hunting ceased, the population is estimated to have grown by 7% a year.
The southern right whale spends summer in the far Southern Ocean feeding, probably close toAntarctica. If the opportunity arises, feeding can occur even in temperate waters such as alongBuenos Aires.[40][41] It migrates north in winter for breeding and can be seen by the coasts of Argentina, Australia, Brazil, Chile, Namibia, Mozambique, Peru,Tristan de Cunha, Uruguay, Madagascar, New Zealand and South Africa; whales have also been known to winter in sub-Antarctic regions.[42][43] It appears that the South American, South African and Australasian groups intermix very little if at all, because maternal fidelity to feeding and calving habitats is very strong. The mother also passes these choices to her calves.[44]
Right whales do not normally cross the warm equatorial waters to connect with the other species and (inter)breed: their thick layers of insulatingblubber make it difficult for them to dissipate their internal body heat in tropical waters. Based on historical records and unconfirmed sightings in modern periods,E. australis transits may sometimes occur through equatorial waters.[45]
Whaling records for the hemisphere include a whaling ground in the central northern Indian Ocean[46] and recent sightings among near-equatorial regions. If the sighting offKiribati was truly ofE. australis, this species may have crossed theEquator on irregular occasions and their original distributions might have been much broader and more northerly distributed than is currently believed.[45][47] A stranding of a 21.3 m (71 feet) right whale atGajana, northwestern India in November 1944 was reported, but the true identity of this animal is unclear.[48][49]
Aside from impacts on whales and environments caused by mankind, their distributions and residences could be largely affected by presences of natural predators or enemies,[42] and similar trends are also probable for other subspecies.[50]
Many locations throughout theSouthern Hemisphere were named after current or former presences of southern rights, includingWalvis Bay,Punta Ballena,Right Whale Bay,Otago Harbour,Whangarei Harbour,Foveaux Strait,[51]South Taranaki Bight,Moutohora Island andWineglass Bay.
Hermanus in South Africa has become known as a centre for whale watching. During the Southern Hemisphere winter months (June – October) the southern right whales migrate to the coastal waters of South Africa, with more than 100 whales known to visit the Hermanus area. Whilst in the area, the whales can be seen with their young as they come toWalker Bay to calve and mate. Many behaviours such as breaching, sailing, lobtailing, or spyhopping can be witnessed. InFalse Bay whales can be seen from the shore from July to October while bothPlettenberg Bay andAlgoa Bay are also home to the southern right whales from July to December. They can be viewed from land as well as by boat with licensed operators conducting ocean safaris throughout the year.
Recent increases in numbers of whales visiting the north-eastern part of South Africa, the so-calledDolphin Coast such as aroundBallito[52] and offUmdloti Beach,[53] indicates the whales' normal ranges are expanding and that re-colonising historical habitats will likely continue as more whales migrate further north.
In Namibia, the majority of confirmed whales are restricted to the south ofLuderitz, on the southwestern coast. Only a handful of animals venture further north to historical breeding grounds such as at Walvis Bay, but their numbers are slowly increasing. Until illegal hunting ceased, whales were rare along Namibian shores, with no sighting recorded north ofOrange River until 1971.[54] Calving activities were first confirmed as recently as the 1980s.[55]
Historical records suggest that this whale's regular range could have once reached further northwards up the coasts ofCape Fria (northern Namibia)[56] andAngola as far asBaia dos Tigres (Tiger Bay).[57][56]
Whaling is known to have been carried out off the coast ofGabon,[45] for example atCape Lopez, and there have been a few confirmed and unconfirmed sightings including one by Jim Darling, a renowned whale researcher.[58][59][60]
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Southern right whales have been spotted in very small numbers off Mozambique[61] and Madagascar.[62] Whales were historically seen in large numbers at various locations such as off the coast ofDurban, inDelagoa/Maputo Bay,[63]Inhaca Island,Ponta do Ouro, and around theBazaruto Archipelago.[24] The first sighting off Mozambique since the end of whaling was in 1997.[64] In recent years, more whales seem to migrate further north to calve, such as atÎle Sainte-Marie,[65][66][67][68]Antongil Bay,[59]Fort Dauphin[69]Toliara,[70]Anakao,Andavadoaka, andAntsiranana Bay,[71][72][73] at Madagascar's northern tip. Infrequent sightings have been confirmed off the island ofMayotte.[74] Whales were historically taken off the coast of Tanzania, and may still be present occasionally aroundZanzibar.[75]
Due to illegal whaling by theUSSR, the recovery of many stocks including the population offTristan da Cunha[76] and adjacent areas such asGough Island has been severely hindered, resulting in relatively few numbers of visiting animals.
Based on catch records and recent observations, right whales may be seen as far north as the islands ofSaint Helena andAscension Island.[47][77]
In Brazil, more than 300 individuals have been cataloged through photo identification (using head callosities) by the Brazilian Right Whale Project, maintained jointly byPetrobras (the Brazilian state-owned oil company), and theconservation group, theInternational Wildlife Coalition. The State ofSanta Catarina hosts a concentration of breeding and calving right whales from June to November, and females from this population also calve off ArgentinianPatagonia andUruguay. In recent years, possibly due to changing habitat environments by human activities and conflicts with local fisheries, the number of whales visiting the coasts is decreasing.[78] Sighting in locations other than Santa Catarina andRio Grande do Sul[79] remain sporadic, such as alongCidreira,[80]Rio de Janeiro coasts like Sepetiba Bay (pt),[81]Cabo Frio,[82][83]Macaé,[84]Prado, Bahia,[85][86] Castelhanos Bay inIlha Bela,[87][88][89]São Paulo coasts[90] such as withinIlha Anchieta State Park,[91] Honey Island,[92][93][94] and bays and estuaries ofParanaguá andSuperagui National Park,[95]Paraná,[96][97][98] and even entering into the lagoon ofLagoa dos Patos.[99][100] Recent studies[101] also show a decrease in the number of sightings along the southeastern Brazilian coast, which includes the highly urbanized States ofSão Paulo andRio de Janeiro.
Further north, small numbers of whales migrate every year to winter or calve inBahia,[25] in particular at theAbrolhos Archipelago. Here, certain individuals are recorded returning at intervals of 3 or 4 years.[102] Whaling records including those prior to Maury and Townsend indicate that right whales were once more frequent visitors further north, for example atSalvador, Bahia.[45][47]
Argentina hosts the world's largest breeding population of southern right whales atPenínsula Valdés,Chubut province, with over 2000 estimated individuals gathering on the gulfs of the peninsula during breeding season. The whales are considered a "natural monument" and protected under Argentine law, and there is a developed whale-watching tourism around them.
During the 2012 annual meeting of the International Whaling Commission's Scientific Committee, data was presented regarding the continued phenomenon of southern right whalestrandings and high rate of mortality atPenínsula Valdés. Between 2003 and 2011, a total of 482 dead right whales were recorded at Península Valdés. There were at least 55 whale deaths in 2010, and 61 in 2011. As in previous years, the vast majority of strandings were calves of the season.[103]There have been increasing sightings in various other locations in recent years, such as onGolfo San Jorge,[104]Tierra del Fuego,[105][106]Puerto Deseado,[107][108]Mar del Plata,[109][110]Miramar, Buenos Aires,[111][112] andBahía Blanca.[113]
In Uruguay, coastal areas such asPunta del Este host congregating sites for whales in breeding seasons, but these are not likely to be calving grounds.[114] In 2013 the Uruguayan parliament approved the creation of a whale sanctuary offLatin America[115] to aid the recovery of the population. The creation of this protected area had been prevented for nearly a decade by pro-whaling nations such as Japan.
For the critically endangered Chile/Peru population, theCetacean Conservation Center (CCC) has been working on a separate programme for right whales. This population, containing no more than 50 individuals, is under threat from an increase in shipping lanes and the fishing industries.[116] 124 sightings in total were recorded during the period 1964–2008.[117] Aside from vagrants' records, Peru's coastlines possibly host one of the northernmost confirmed range of the species along with Gabon,[45]Senegal,Tanzania, Brazilian coasts, Madagascar, Indian Ocean, western Australia, Kermadec Islands, and tropical waters includingSouth Pacific Islands.[45] TheAlfaguara project targeting cetaceans inChiloe[118][119] may possibly target this species as well in the future since calving activities have been confirmed inChiloé Archipelago.[120] Foraging grounds of this population is currently undetected, but possibly Chiloé and down south ofCaleta Zorra to southernfiords such as fromPenas Gulf toBeagle Channel although numbers of confirmations are small in theBeagle Channel.[121] Hopes are arising for the establishment of a new tourism industry on the eastern side of theStrait of Magellan,[122] especially nearCape Virgenes[123] andPunta Dungeness, as the number of sightings increases.[124][125][126] It is unknown whether these increases are due to re-colonisation by whales from the Patagonian population.
Occurrences of brindle individuals have been confirmed from this population as well.[127][128]
Historically, populations of southern right whales inOceanian regions were robust.[47] Early settlers of theRiver Derwent in Tasmania complained that sounds of cavorting whales kept them awake at night.[129] (Similar stories exist aboutWellington, New Zealand,[129] but no primary sources could be found to support them.[130]) In July 1804, clergyman Robert Knopwood claimed that in crossing the River Derwent, "we passed so many whales that it was dangerous for the boat to go up the river unless you kept very near the shore".[131] By the 1890s southern right whales had been brought to the brink of extinction, with over 25,000 whales killed in Australia and New Zealand.[132]
Studies of population structure and mating systems have shown that the southwest Australian and New Zealand populations are genetically differentiated.[133] The results of satellite tracking suggest that there are at least some interactions between populations in Australia and New Zealand,[134][135] but the extent of this is unknown. The two groups may share migratory corridors and calving grounds.[133] The return of southern right whales to the Derwent River and other parts of Australia in recent decades is a sign that they are slowly recovering from their earlier exploitation to near extinction.[132]
Southern right whales in Australian waters show higher rate of recoveries, as they have increased from 2,100 whales in 2008[136] to 3,500 in 2010.[29] Two genetically distinct groups inhabit Australian waters: the southwestern population of 2,900 whales – in 2012 currently holding the majority of the overall Australian population – and the critically endangered southeastern group, counting only dozens to 300 individuals.
Right whales can be found in many parts of southern Australia, where the largest population is found at theHead of the Bight inSouth Australia, a sparsely populated area south of the middle of theNullarbor Plain. Over 100[137] individuals are seen there annually from June to October. Visitors can view the whales from cliff-top boardwalks and lookouts, with whales swimming almost directly below, or by taking a scenic flight over the marine park. A more accessible South Australian location for viewing whales isEncounter Bay where the whales can be seen just off the beaches of theFleurieu Peninsula, centred around the surfing town ofMiddleton. The whales have established a newer nursery-ground nearEyre Peninsula, especially atFowlers Bay. Numbers are much smaller at these locations compared to those in the Bight, with an average of a couple of whales per day, but as of 2009[update] there were regular sightings of more than ten whales at a time off Basham Beach, near Middleton.[138] The South Australian Whale Centre atVictor Harbor has information on the history of whaling and whale-watching in the area, and maintains an on-line database of whale sightings.[139]In June 2021 a female gave birth offChristies Beach, a southern suburb of Adelaide, and remained in the shallows off the beach for some time, attracting large crowds.[140]
Whale numbers are scarcer inVictoria, where the only established breeding ground which whales use each year, in very small numbers, is atWarrnambool. However, as the whales do seem to be increasing in number generally, but not showing any dramatic increases at Warrnambool, they may be extending their wintering habitats into other areas of Victoria, where the numbers of sightings are slowly increasing. These areas include aroundMelbourne, such as inPort Phillip Bay, alongWaratah Bay, atOcean Grove, Warrnambool, onMornington Peninsula, inApollo Bay, and onGippsland coasts and atWilsons Promontory.[141]
Whale numbers inTasmania are relatively small, however sightings have increased in recent years. Some whales migrate through Tasmanian waters while some others remain throughout wintering seasons.[142]
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Waters off the coasts ofWestern Australia,New South Wales, andQueensland coasts have all historically been inhabited by whales. Their historical range was much wider than it is today, and reached around the southern coast of the continent, extending up toAustralian Abrolhos Island,[143]Exmouth andShark Bay on the west coast, and on the east coast as far north asHervey Bay,Moreton Bay[144] andGreat Barrier Reef.[145] Today, the east-coast population remains endangered and very small (in the low-tens),[146] contributing to small numbers and limited re-colonization, but increases have been confirmed in many areas such asPort Jackson,Port Stephens,Twofold Bay,Jervis Bay,Broulee,[147]Moruya River,[148][149]Narooma,[150] andByron Bay.[151] 12 foraging areas have been officially announced by the Australian government.[152]
In sub-Antarctic regions, numbers of whales visiting long-used habitats differ drastically by location. The population is recovering well at theNew Zealand Subantarctic Islands, while whale numbers are less successful atMacquarie Island.[153]
It is not known whether Australian populations will re-colonise historical oceanic habitats such asNorfolk Island andLord Howe Island withLord Howe Seamount Chain (historically known as the "Middle Ground" for whalers[154][need quotation to verify][155])in the future.
The current population of right whales in New Zealand waters is difficult to establish. However, studies by theDepartment of Conservation and sightings reported by locals have helped to build up a better picture.[156] The pre-exploitation size of the New Zealand group is estimated at between 28,800 and 47,100 whales. 35,000 – 41,000 catches were made between 1827 and 1980. The number of whales surviving commercial and illegal whaling operations is estimated to have decreased to just 110 whales (around 30 of which were females) in 1915.[133][157] As a result of such a steep decline in numbers, the population of southern right whales in this region has experienced apopulation bottleneck and suffers from low genetic diversity.[158]
The population at the sub-AntarcticAuckland Islands is showing a remarkable recovery but continues to have some of the lowest genetic diversities in the world.[158] In theCampbell Islands, recovery is slower.[43] Here, the population is estimated to have dropped to as low as 20 individuals post WWII.[134] There had been no confirmed sightings or strandings of right whales for 36 years until 1963 when four separate sightings including a cow-calf pair were made over a wide area. Remnants of sub-Antarctic populations were reported in the 1980s and re-discovered in the 1990s.[134]
Today, the majority of right whales congregate at the Auckland and Campbell Islands, where they form exceptionally dense and limited congregations including mating adults and calving females. In the waters aroundPort Ross[159] up to 200 whales may winter at the same time.[160] It is notable that whales of all age groups[161] are present in this small area annually, not only using them as feeding and summering[162] grounds but also for wintering, breeding, and calving during harsh, cold periods. Low genetic diversity as a result of population decline has caused changes in skin coloration amongst this group.[158]Scientists used to believe there was a very small remnant population of southern right whales inhabiting New Zealand's main islands (North and South Island), estimated to contain 11 reproductive females.[163] In winter, whales migrate north to New Zealand waters and large concentrations occasionally visit the southern coasts of South Island. Bay areas alongFoveaux Strait fromFiordland region to northernOtago are important breeding habitats for right whales, especiallyPreservation,[164]Chalky Inlets,[165]Te Waewae Bay,[166] andOtago Peninsula.[167][168] Calving activities are observed all around New Zealand, but with more regularity around North Island shores from theTaranaki coast in the west toHawke's Bay,Bay of Plenty in the east, and areas inHauraki Gulf such asFirth of Thames orBay of Islands in the north.
There are various parts of the nation where large numbers of whales were seen historically, but sightings are less common nowadays. These areas include theMarlborough Region, especially fromClifford Bay andCloudy Bay toPort Underwood,[169]Golden Bay, Awaroa Bay, and coastlines onWest Coast andHokianga Harbour in Northland. Other than a handful of confirmed observations, very little information is available for modern migrations to historical oceanic habitats ofKermadec Islands[170][171] andChatham Islands.[172] The northernmost sighting recorded historically was at 27°S.[173]
A 2009 study revealed that the right whale populations from New Zealand's main islands and the sub-Antarctic islands interbreed, though it is still unknown whether the two stock originally came from a single population.[174] Feeding areas in pelagic waters are unclear while congregations have been confirmed along the southern edge of theChatham Rise.[175]
Some Australian ranges are located close to the ranges of New Zealand groups (Norfolk Island, Macquarie Island). It is unclear whether whales historically or currently from these Australian ranges once originated in New Zealand groups.
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In oceanic islands and offshore waters other than the above-mentioned areas, very little about the presence and recovery status of southern right whales is known. Right whales' historical ranges were much greater than today; during the whaling era of the 19th century whales were known to occur in lower latitude areas such as around thePacific Islands, off theGilbert Islands (nowadaysKiribati),[176] and also to frequent lower latitudes of the central Indian Ocean.
It is unclear whether right whales have been historically or currently distributed among parts of hemisphere lacking great land masses and reached far more pelagic islands such asAlejandro Selkirk andRobinson Crusoe Islands,Hanga Roa,Pitcairn,Galapagos Islands, and theEaster Island.
Populations among sub-Antarctic islands in theScotia Sea[79] such asSouth Georgia and the South Sandwich Islands andFalkland Islands were severely damaged and show slower recoveries today. Antarctic distributions are difficult to establish due to low levels of sightings around oceanic islands in these areas, includingElephant Island.[a]
Historically, there were known to be populations which summered in theCrozet Islands and theKerguelen Islands, and migrated toLa Roche Godon andÎle Saint-Paul,Île Amsterdam, and the Central Indian Ocean. They may be distinct from the population of whales seen on Mozambique coasts.[177] Repopulation of whales among these areas of the Indian Ocean is likely to be happening at even lower rates than in other areas. Sightings have been fewer in modern periods among Crozet,[178][179]Réunion,[180][63][181][182]Mauritius,Marion Islands,[42] Île Amsterdam, and Kerguelen.[183]
Killings of these whales have been recorded on central Indian Ocean near the equator, especially around the area betweenDiego Garcia,Egmont Islands, and theGreat Chagos Bank in the west, and theCocos (Keeling) Islands in the east. The range of whales in the Indian Ocean is comparable to the range of some other populations aroundSouth America,Africa, and the South Pacific islands includingKiribati, the northernmost reach of all the populations known today.[46]
By 1750 theNorth Atlantic right whale was as good as extinct for commercial purposes, and the Americanwhalers moved into the South Atlantic before the end of the 18th century. The most southerly Brazilian whaling station was established in 1796, inImbituba. Over the next hundred years, American whaling spread into the Southern and Pacific Oceans, where the American fleet was joined by fleets from several European nations.
The southern right whale had been coming to Australian and New Zealand waters in large numbers before the 19th century, but was extensively hunted from 1800 to 1850. Hunting gradually declined with the whale population and then all but ended in coastal waters in Australasia.[184] The beginning of the 20th century brought industrial whaling, and the catch grew rapidly. By 1937, according to whalers' records, 38,000 were harpooned in the South Atlantic, 39,000 in the South Pacific, and 1,300 in theIndian Ocean. Given the incompleteness of these records, the total take was somewhat higher.[185]
As it became clear that the population was nearly depleted, the harpooning of right whales was banned in 1937. The ban was largely successful, although some illegal whaling continued for several decades.Madeira took its last two right whales in 1968. Illegal whaling continued off the coast of Brazil for years, and the Imbituba station processed right whales until 1973. TheUSSR admitted to taking illegally over 3,300 during the 1950s and 1960s,[186] although it only reported taking 4.[187]
Illegal operations continued even in the 1970s, such as the case in Brazil until 1973.[15] It was also revealed that Japan was supporting these destructive hunts by neglecting and disregarding its monitoring obligations. There were agreements between Japan and the Soviet Union to keep their illegal mass whaling activities in foreign/international protected waters secret.[188]
Right whales began to be seen again in Australian and New Zealand waters from the early 1960s.[184] It is possible that if the Soviet hunts had never happened, the New Zealand population would be three or four times larger than its current size.[189]
The southern right whale, listed as "endangered" by CITES, is protected by all countries with known breeding populations (Argentina, Australia, Brazil, Chile, New Zealand, South Africa and Uruguay). In Argentina, it is considered a "Natural Monument" under national law Nº 23094, with all whales sighted on Argentine waters under legal protection. In Brazil, a federalEnvironmental Protection Area encompassing some 1,560 km2 (600 sq mi) and 130 km (81 mi) of coastline in Santa Catarina State was established in 2000 to protect the species' main breeding grounds in Brazil and promote regulated whale watching.[190] The southern right whale is listed on Appendix I[191] of the Convention on the Conservation of Migratory Species of Wild Animals (CMS) as this species has been categorized as being in danger of extinction throughout all or a significant proportion of their range. This species is also covered by the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MoU).[192] In 2017, the IUCN Red List of Threatened Species listed the species' status as Least Concern with a population trend listed as "unknown".[193]
In Australia, Southern right whales are listed for protection variously under state and federal legislation, as reflected in the table below:
| Jurisdiction | Status | Legislation | Year of last revision | Reference |
|---|---|---|---|---|
| Australia | Endangered | EPBC Act 1999 | 2000 | [194] |
| Western Australia | Vulnerable | Biodiversity Conservation Act 2016 | [195] | |
| South Australia | Vulnerable | National Parks & Wildlife Act 1972 | [196] | |
| Victoria | Threatened | Flora & Fauna Guarantee Act 1988 | [197] | |
| Tasmania | Endangered | Threatened Species Protection Act 1995 | [198] |
A two-year, £740,000 project, led by theBritish Antarctic Survey began in 2016, to discover why almost 500 young have been washed up on the Valdes Peninsula over the last ten years. The project is funded by the UK'sDepartment for Environment, Food and Rural Affairs (Defra) and the EU. Possible reasons are a lack ofkrill in the whale feeding grounds atSouth Georgia and the South Sandwich Islands, exposure to toxic algae and attacks by kelp gulls (Larus dominicanus).[199]
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One possibly significant contributor to the calf mortality rate has alarmed scientists – since at least 1996,kelp gulls off the coast of Patagonia have been observed attacking and feeding on live right whales.[200] The kelp gull uses its powerful beak to peck down several centimetres into the skin and blubber, often leaving the whales with large open sores – some of which have been observed to be half a metre in diameter. This predatory behaviour, primarily targeted towards mother/calf pairs, has been continually documented in Argentinian waters, and continues today. Observers note that the whales are spending up to a third of their time and energy performing evasive manoeuvres – therefore, mothers spend less time nursing, and the calves are thinner and weaker as a result. Researchers speculate that many years ago, waste from fish processing plants allowed the gull populations to soar. Their resulting overpopulation, combined with reduced waste output, caused the gulls to seek out this alternative food source.[201] Scientists fear that the gulls' learned behaviour could proliferate, and the IWC Scientific Committee has urged Brazil to consider taking immediate action if and when similar gull behaviour is observed in their waters. Such action may include the removal of attacking gulls, following Argentina's lead in attempting to reverse the trend.[103]
Southern right whales are threatened by entanglement in commercial fishing gear andship strikes.[5] Entanglement in fishing gear can cut through a whale's skin, causing infection, amputation and death. Underwater noise from human activities such asdrilling and dredging can interfere with whales' communication, and deter them from their usual habitats and breeding grounds.[202]
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The southern right whale has madeHermanus, South Africa, one of the world centres forwhale watching. During the winter months (June to October), southern right whales come so close to the shoreline that visitors can watch them from the shore as well as from strategically placed hotels. The town employs a "whale crier" (cf.town crier) to walk through the town announcing where whales have been seen.[203] Hermanus also has two boat–based whale watching operators. Southern right whales can also be watched at False Bay from the shore or from the boats of operators in Simon's Town. Plettenberg Bay along the Garden Route of South Africa is also known for whale watching including both land and boat based watching, not only for southern rights (July to December) but throughout the year.[204] Southern right whales can also be seen off the coast ofPort Elizabeth with marine eco tours running from the Port Elizabeth harbour, as some southern right whales make Algoa Bay their home for the winter months.[205]
Although southern right whales have been seen in neighboring countries including Namibia, Mozambique, and Madagascar, they are not the targeted species for whale watching tours in these countries.
In Brazil, Imbituba inSanta Catarina has been recognised as the National Right Whale Capital and holds annual Right Whale Week celebrations in September, when mothers and calves are more often seen. The old whaling station there is now a museum that documents the history of right whales in Brazil. In Argentina,Península Valdés inPatagonia hosts (in winter) the largest breeding population, with more than 2,000 catalogued by theWhale Conservation Institute andOcean Alliance.[206] As in the south of Argentina, the whales come within 200 m (660 ft) of the main beach in the city of Puerto Madryn and form a part of the largeecotourism industry. Uruguay's Parliament on 4 September 2013, has become the first country in the world to make all of its territorial waters a haven for whales and dolphins. Every year, dozens of whales are sighted, especially in the departments of Maldonado and Rocha during winter.[207] Swimming activities for commercial objectives had been banned in the area in 1985,[208] but were legalised inGulf of San Matías, the only place in the world where humans are formally allowed to swim with the species.[209] Land-based watching and occasional kayaking with whales activities are seen at other locations not renowned for whale-watching as much asPuerto Madryn and with less restrictions on approaching whales, such as at Puerto Deseado,[210][211][212] Mar del Plata,[213][214] and Miramar in Buenos Aires.[215][216][217][218]
Though their numbers are dangerously small, land-based sightings of whales are on the increase in recent years off Chile and Peru, with some hope of creating new tourism industries,[219] especially in theStrait of Magellan, most notably aroundCape Virgenes.[125]
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In Australia's winter and spring, southern right whales can be seen migrating along theGreat Australian Bight in South Australia. Viewing locations include theBunda Cliffs and Twin Rocks, theHead of the Bight (where a visitor centre and cliff-top viewing boardwalks exist) and atFowler's Bay where accommodation and charter boat tours are offered.[13] Another popular South Australian locality for Southern right whale watching isEncounter Bay, where the South Australian Whale Centre supports local whale-watchers and tourists. InWarrnambool,Victoria, a right whale nursery is also a popular tourist attraction. The whales' migratory range is extending as the species continues to recover and re-colonize other areas of the continent, including the coastal waters ofNew South Wales andTasmania. In Tasmania, the first birth since the 19th century was recorded in 2010 in theRiver Derwent.
Similarly, southern right whales may provide chances for the public to observe whales from shore on New Zealand's coasts with greater regularity than in the past, especially in southernFiordland,Southland through to theOtago coast,[220] and on theNorth Island coast, especially inNorthland and other locations such as theBay of Plenty and theSouth Taranaki Bight. Births of calves could have always been occurring on the main islands' coasts, but were confirmed with two cow-calf pairs in 2012.[221][222]
In theSubantarctic Islands and in the vicinity ofAntarctica,[223] where few regulations exist or are enforced, whales can be observed on expedition tours with increasing probability. TheAuckland Islands are a specially designated sanctuary for right whales, where whale-watching tourism is prohibited without authorisation.[224]
The species was featured on a 70pcommemorative stamp issued byTristan da Cunha in 2019 as part of a set celebrating different species of whale.[225]
{{cite web}}: CS1 maint: numeric names: authors list (link){{cite journal}}:Cite journal requires|journal= (help){{cite journal}}:Cite journal requires|journal= (help){{cite magazine}}:Cite magazine requires|magazine= (help){{cite journal}}:Cite journal requires|journal= (help){{cite journal}}:Cite journal requires|journal= (help){{cite journal}}:Cite journal requires|journal= (help)[...] a voyage of three years became the norm as the whalers followed the migrating whales on a seasonal pattern which took them north to Japan, across the Pacific to the 'middle ground' off the coast of South America, and down to New Zealand.
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