Southern right whale
The southern right whale (Eubalaena australis) is a baleen whale, one of three species classified as right whales belonging to the genus Eubalaena. Like other right whales, the southern right whale is readily distinguished from others by the callosities on its head, a broad back without a dorsal 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 related North Atlantic and the North Pacific right whales, displaying only minor skull differences. It may have fewer callosities on its head and more on its lower lips than the two northern species. Approximately 10,000 southern right whales are spread throughout the southern part of the Southern Hemisphere.
The maximum size of an adult female is 15 m (49 ft) and can weigh up to 47 tonnes (46 long tons; 52 short tons). The testicles of right whales are likely to be the largest of any animal, each weighing around 500 kg (1,100 lb). This suggests that sperm competition is important in the mating process. Right whales cannot cross the warm equatorial waters to connect with the other (sub)species and (inter)breed: their thick layers of insulating blubber make it impossible for them to dissipate their internal body heat in tropical waters.
Taxonomy[edit source | edit]
The right whales were first classified in the Balaena genus in 1758 by Carolus Linnaeus, who at the time considered all of the right whales (including the bowhead) as a single species. Through the 1800s and 1900s, in fact, the Balaenidae family has been the subject of great taxonometric debate. Authorities have repeatedly recategorized 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.
The southern right whale was initially described as Balaena australis by Desmoulins in 1822. Eventually, it was recognized that bowheads and right whales were in fact different, and John Edward Gray proposed the Eubalaena genus 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 the Southern Ocean. 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) and Balaena mysticetus (the bowheads).
In 2000, Rosenbaum et al. disagreed, based on data from their genetic study of DNA samples from each of the whale populations. Genetic evidence now clearly demonstrates 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.
It is believed that the right whale populations first split because of the joining of North and South America. The rising temperatures at the equator then created a second split, into the northern and southern groups, preventing them from interbreeding.
The cladogram is a tool for visualizing and comparing the evolutionary relationships between taxa. 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 Balaenidae family serves to illustrate the current scientific consensus as to the relationships between the southern right whale and the other members of its family.
Other junior synonyms for E. australis have included B. antarctica (Lesson, 1828), B. antipodarum (Gray, 1843), Hunterus temminckii (Gray, 1864), and E. glacialis australis (Tomilin, 1962) (see side panel for more synonyms).
Behavior[edit source | edit]
One behavior unique to the southern right whale, known as sailing, is that of using their elevated flukes to catch the wind. It appears to be a form of play and is commonly seen off the coast of Argentina and South Africa.
Population and distribution[edit source | edit]
The southern right whale spends summer in the far Southern Ocean feeding, probably close to Antarctica. 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. The total population is estimated to be around 10,000. Since hunting ceased, stocks are estimated to have grown by 7% a year. 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.
The most recent population estimates, published by National Geographic in October 2008, put the southern whale population at 10,000. The estimate of 7,000 followed a March 1998 IWC workshop. Researchers used data about adult female populations from three surveys (one in each of Argentina, South Africa and Australia, collected during the 1990s) and extrapolated to include unsurveyed areas, number of males and calves using available male:female and adult:calf ratios to give an estimated 1999 figure of 7,500 animals.
South Africa[edit source | edit]
Hermanus has become known as a mecca for whale watching, during the southern hemisphere winter months (June - October) the Southern Right Whales migrate to the coastal waters of South Africa, with in excess of 100 whales known to be in the Hermanus area. Whilst in the area, the whales can be seen with their young as they come to Walker Bay to calve and mate. Many behaviours such as breaching, sailing, lobtailing, or spyhopping can be witnessed.
In False Bay whales can be seen from the shore from July to October while both Plettenberg Bay and Algoa 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.
New Zealand[edit source | edit]
Many features are still unknown about right whale populations in New Zealand waters. However, studies by Department of Conservation and sightings reported by locals helped to deepen understanding. 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), containing probably 11 reproductive females. In winter, whales migrate north to New Zealand waters and large concentrations occasionally visit the southern coasts of South Island. Bay areas along Foveaux Strait from Fiordland region to northern Otago are important breeding habitats for right whales, especially Preservation Inlet, Te Waewae Bay, and Otago coast. Calving activities are observed all around the nation, but with more regularity around North Island shores from Taranaki coast in west to Hawke's Bay, Bay of Plenty in east, and Hauraki Gulf or Bay of Islands in north. The population at sub-Antarctic Auckland Islands is showing a remarkable recovery while recovery state in Campbell Islands are slower.
Recent study revealed that the right whale populations from New Zealand's main islands and the one from sub-Antarctic islands interbreed though it is still unknown whether the two stock originally came from a single population.
Brazil/Argentina[edit source | edit]
In Brazil, more than 300 individuals have been cataloged through photo identification (using head callosities) by the Brazilian Right Whale Project, maintained jointly by Petrobras (the Brazilian state-owned oil company) and the International Wildlife Coalition. The State of Santa Catarina hosts a concentration of breeding and calving right whales from June to November, and females from this population also calve off Argentinian Patagonia and Uruguay.
During the 2012 annual meeting of the International Whaling Commission's Scientific Committee, data was presented regarding the continued phenomena of southern right whale strandings and high rate of mortality at Península Valdés, Argentina. 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.
Australia[edit source | edit]
Southern Right Whales can be found in many parts of southern Australia, with the largest population to be found at the Head of the Bight in South Australia. Over 100 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. The Head of the Bight is located in a sparsely populated area in the middle of the Nullabor. A more accessible location for viewing whales in South Australia is Encounter Bay where the whales can be seen just off the beaches of the Fleurieu Peninsular centred around the surfing town of Middleton, South Australia. Numbers are much smaller at this location compared to the Bight, with an average of a couple of whales per day. In recent years there have been regular sightings of more than ten whales at a time off Basham Beach. A Whale Centre for information on the history of whaling and now whale watching in the area can be found at Victor Harbor.
Gull attacks[edit source | edit]
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. 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 meter in diameter. This predatory behavior, 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 maneuvers – 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. 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.
Whaling[edit source | edit]
By 1750 the North Atlantic right whale was as good as extinct for commercial purposes and the Yankee whalers moved into the South Atlantic before the end of the 18th century. The southernmost Brazilian whaling station was established in 1796, in Imbituba. Over the next one hundred years, Yankee 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 New Zealand waters in large numbers before the 19th century, but was extensively hunted from 1830-1850. Hunting gradually declined with the whale population and then all but ended in coastal New Zealand waters. The beginning of the 20th century brought industrial whaling, and the catch grew rapidly. By 1937, according to whalers' records, 38,000 were captured in the South Atlantic, 39,000 in the South Pacific, and 1,300 in the Indian Ocean. Given the incompleteness of these records, the total take was somewhat higher.
As it became clear that stocks were nearly depleted, right whaling 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 many years and the Imbituba station processed right whales until 1973. The Soviet Union admitted illegally taking over 3,300 during the 1950s and '60s, although it only reported taking 4.
Whales began to be seen again in Australian and New Zealand waters from the early 1960s.
Conservation[edit source | edit]
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 Brazil, a federal Environmental 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.
The Southern right whale is listed on Appendix I 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.
Whale watching[edit source | edit]
The southern right whale has made Hermanus, South Africa one of the world centers for whale 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. Hermanus also has two boat–based whale watching operators. The town employs a "whale crier" (cf. town crier) to walk through the town announcing where whales have been seen. Southern right whales can also be watched at other winter breeding grounds. In False Bay whale-watching can be done from the shore or from the boats of licensed operators in Simon's Town. Plettenberg Bay along the Garden Route of South Africa is another mecca for whale watching not only for Southern Rights (July to December)but throughout the year. There are both land based and Ocean Safaris boat based Whale encounters on offer in this beautiful town. Southern right whales can also be seen off the coast of Port 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.
In Brazil, Imbituba in Santa Catarina has been recognized 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 in Patagonia hosts (in winter) the largest breeding population, with more than 2,000 catalogued by the Whale Conservation Institute and Ocean Alliance. 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 large ecotourism industry.
In Australia's winter and spring, southern right whales can be seen from the Bunda Cliffs and Twin Rocks, both along the remote Great Australian Bight in South Australia. In Warrnambool, Victoria, there exists a nursery which is popular with tourists in the winter and spring.
Uruguay's Parliament on September 4, 2013, has become the first country in the world to make all of its territorial waters a safehaven for whales and dolphins. Every year, dozens of whales are sighted, especially in the departments of Maldonado and Rocha during the months of winter.
See also[edit source | edit]
References[edit source | edit]
- Mead, J. G.; Brownell, R. L., Jr. (2005). "Order Cetacea". In Wilson, D. E.; Reeder, D. M. Mammal Species of the World (3rd ed.). Johns Hopkins University Press. pp. 723–743. ISBN 978-0-8018-8221-0. OCLC 62265494.
- Reilly, S.B., Bannister, J.L., Best, P.B., Brown, M., Brownell Jr., R.L., Butterworth, D.S., Clapham, P.J., Cooke, J., Donovan, G.P., Urbán, J. & Zerbini, A.N. (2008). "Eubalaena australis". IUCN Red List of Threatened Species. Version 2009.1. International Union for Conservation of Nature. Retrieved 12 September 2009.
- Perrin, W.F. (2012). "Eubalaena australis Desmoulins, 1822". World Cetacea Database. Retrieved 29 September 2012.
- Carwardine MH, Hoyt E (1998). Whales, Dolphins and Porpoises. Surry Hills, NSW: Reader's Digest. ISBN 0-86449-096-8.
- Müller, J. (1954). "Observations of the orbital region of the skull of the Mystacoceti" (PDF). Zoologische Mededelingen 32: 239–90.
- Branch, G.M., Branch, M.L, Griffiths, C.L. and Beckley, L.E. 2010. Two Oceans: a guide to the marine life of southern Africa ISBN 978-1-77007-772-0
- Crane, J. and R. Scott. (2002). "Eubalaena glacialis". Animal Diversity Web. Retrieved 27 June 2009.
- Rice, Dale W. (1998). "Marine mammals of the world: systematics and distribution". Society of Marine Mammalogy Special Publication Number 4: 231pp.
- Rosenbaum, H. C., R. L. Brownell Jr.; M. W. Brown C. Schaeff, V. Portway, B. N. White, S. Malik, L. A. Pastene, N. J. Patenaude, C. S. Baker, M. Goto, P. Best, P. J. Clapham, P. Hamilton, M. Moore, R. Payne, V. Rowntree, C. T. Tynan, J. L. Bannister and R. Desalle (2000). "World-wide genetic differentiation of Eubalaena: Questioning the number of right whale species" (PDF). Molecular Ecology 9 (11): 1793–802. doi:10.1046/j.1365-294x.2000.01066.x. PMID 11091315.
- Palaeobiology and Biodiversity Research Group, University of Bristol
- "List of Marine Mammal Species and Subspecies". Committee on Taxonomy. Society for Marine Mammology. 3 April 2012. Retrieved 29 September 2012.
- Kenney, Robert D. (2008). "Right Whales (Eubalaena glacialis, E. japonica, and E. australis)". In Perrin, W. F.; Wursig, B.; Thewissen, J. G. M. Encyclopedia of Marine Mammals. Academic Press. pp. 962–69. ISBN 978-0-12-373553-9. Retrieved 20 May 2012.
- Right Whale News, May 1998. Retrieved 24 July 2007.
- Patenaude, Nathalie J. "Sightings of southern right whales around ‘mainland’ New Zealand". Department of Conservation, Wellington, NZ. Retrieved May 2013.
- "Fiordland Coastal Newsletter". Department of Conservation, Invercargill, NZ. Retrieved May 2013.
- "Southern right whales - something really special: Media release 22 October 2009". Doc.govt.nz. 22 October 2009. Retrieved 16 June 2012.
- "Otago 'hot spot' for whale sightings - Otago Daily Times". Rebecca Fox. 7 April 2013. Retrieved 9 April 2013.
- "Southern whales the right stuff for new era - Whales and Whaling - NZ Herald News". 188.8.131.52. Retrieved 16 June 2012.
- "Southern right whale expedition 2009: Media release 1 September 2009". Doc.govt.nz. 1 September 2009. Retrieved 16 June 2012.
- "Report of the Scientific Committee; Panama City, Panama, 11–23 June, 2012" (PDF). Annual Meeting of the International Whaling Commission. Panama City, Panama: International Whaling Commission. 2012. pp. 48–49. IWC/64/Rep1Rev1. Retrieved 30 October 2012.
- Increased harassment of Right Whales (Eubalaena australis) by Kelp Gulls (Larus dominicanus) at Península Valdés, Argentina. Rowntree, V.J., P. MacGuiness, K. Marshall, R. Payne, J. Seger, and M. Sironi, 1998. Marine Mammal Science. 14(1): 99 - 115. doi:10.1111/j.1748-7692.1998.tb00693.x
- Gulls' vicious attacks on whales. BBC News, 24 June 2009.
- Gaskin, D.E. (July 1964). "Return of the Southern Right Whale (Eubalaena australis Desm.) to New Zealand Waters, 1963". Tuatara 12 (2): 115–118. Retrieved 22 July 2007.
- Tonnessen, J. N. and A. O. Johnsen (1982). The History of Modern Whaling. United Kingdom: C. Hurst & Co. ISBN 0-905838-23-8.
- Tormosov D.D., Mikhaliev Y.A., Best P.B., Zemsky V.A., Sekiguchi K., Brownell R.L. (November 1998). (abstract) "Soviet catches of southern right whales Eubalaena australis, 1951-1971. Biological data and conservation implications". Biological Conservation 86 (2): 185–197. doi:10.1016/S0006-3207(98)00008-1. Retrieved 22 July 2007.
- Reeves, Randall R., Brent S. Stewart, Phillip J. Clapham and James. A Powell (2002). National Audubon Society: Guide to Marine Mammals of the World. United States: Alfred A. Knopf, Inc. ISBN 0-375-41141-0.
- Petrobras, Projeto Baleia Franca. http://www.baleiafranca.org.br/ More information on Brazilian right whales is available in Portuguese
- "Appendix I" of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). As amended by the Conference of the Parties in 1985, 1988, 1991, 1994, 1997, 1999, 2002, 2005 and 2008. Effective: 5 March 2009.
- Official webpage of the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region
- "Ocean Alliance". Retrieved May 2013.
- "Uruguay se convirtió en un santuario de ballenas y delfines". Ecología. Cromo.com.uy. Retrieved 5 September 2013.