The southern right whale (Eubalaena australis) is a large baleen whale and one of three right whale species in the genus Eubalaena. It lives in the Southern Hemisphere, in oceans between 20° and 60° south. Like its northern relatives, the southern right whale has a broad back with no dorsal fin, a long, curved mouth, and white patches on its head called callosities. Hunted for many years, nearly to extinction, the species is now protected. In 2009, its global population was estimated to be about 13,600.

Each year, the southern right whale migrates. In summer, it feeds on zooplankton and krill in the cold waters of the Southern Ocean, often near Antarctica. In winter, it moves to warmer coastal waters off Argentina, Australia, Brazil, South Africa, and New Zealand to breed and give birth. These whales are known for their active behavior at the surface, such as breaching and a behavior called "tail sailing," where they use their flukes to catch the wind.

Historically, southern right whales were the main target for whalers (hence the name "right whale"), who killed tens of thousands from the 18th to the 20th century, greatly reducing their numbers. International protection began in 1937, though illegal hunting by the Soviet Union continued until the 1970s. After stopping industrialized whaling, the population has grown by about 7% each year. Today, the species is a focus for whale watching, though it still faces threats from ship collisions, entanglement in fishing nets, and pollution.

Taxonomy

Right whales were first grouped into the genus Balaena in 1758 by Carl Linnaeus. At that time, he believed all right whales, including the bowhead whale, were one species. In the 19th and 20th centuries, scientists debated how to classify the family Balaenidae. Experts often changed how they grouped the three right whale populations and the bowhead whale, sometimes as one species, sometimes as two, three, or four species, and sometimes in one or two different genera. During early whaling, all these whales were considered one species, Balaena mysticetus.

The southern right whale was first named Balaena australis by Desmoulins in 1822. Later, scientists realized bowheads and right whales were different. In 1864, John Edward Gray created the genus Eubalaena for right whales. Studies of whale skulls later showed differences between northern and southern right whales, suggesting at least two species: one in the Northern Hemisphere and one in the Southern Ocean. In 1998, Rice listed only two species in his book: Balaena glacialis (all right whales) and Balaena mysticetus (bowheads).

In 2000, Rosenbaum and others used genetic data from whale DNA samples. This research showed that northern and southern right whales have not interbred for 3 to 12 million years, proving the southern right whale is a separate species. Northern Pacific and Atlantic right whales are also distinct. The North Pacific right whale is more closely related to the southern right whale than to the North Atlantic right whale. Genetic differences between E. japonica (North Pacific) and E. australis (South Pacific) are smaller than those seen in other baleen whales across different oceans.

Scientists believe the split between right whale populations began when the Panama isthmus formed, connecting North and South America. Rising equatorial temperatures later caused a second split, separating northern and southern groups and stopping them from interbreeding.

In 2002, the International Whaling Commission accepted Rosenbaum’s findings and recommended keeping the Eubalaena name for this genus.

A cladogram is a tool that shows evolutionary relationships between species. It looks like a branching diagram, with each branch representing a split in evolutionary history. The following cladogram of the Balaenidae family shows the current scientific understanding of the southern right whale’s relationship to other family members.

E. glacialis – North Atlantic right whale
E. japonica – North Pacific right whale
E. australis – southern right whale
B. mysticetus – bowhead whale

Other names for E. australis have included B. antarctica (Lesson, 1828), B. antipodarum (Gray, 1843), Hunterus temminckii (Gray, 1864), and E. glacialis australis (Tomilin, 1962).

Description

The southern right whale can be easily told apart from other whales by the callosities on its head, a wide back without a dorsal fin, and a long, curved mouth that starts above the eye. Its skin is very dark grey or black, and sometimes has white patches on the belly. The callosities on its head appear white because they are covered in large groups of cyamids, which are a type of whale louse. It is very similar to the closely related North Atlantic and North Pacific right whales, with only small differences in the shape of their skulls. It may have fewer callosities on its head than the North Atlantic right whale and more on its lower lips than the two northern species. The exact purpose of callosities is not fully understood, but they may help protect the whale from predators.

An adult female southern right whale can grow up to 15 meters (49 feet) long and weigh up to 47 tonnes (46 long tons; 52 short tons). Some larger whales have been recorded at 17–18 meters (56–59 feet) in length and up to 80 tonnes (79 long tons; 88 short tons) in weight. These whales are slightly smaller than other right whales in the Northern Hemisphere. Each side of the upper jaw has 200–270 baleen plates. These plates are narrow and about 3 meters (9.8 feet) long, and are covered in very thin hairs. The pectoral fin is 1.7 meters (5.6 feet) long. The testicles of right whales are likely the largest of any animal, each weighing about 500 kilograms (1,100 pounds). This suggests that competition between males for mates is important. The penis can be up to 2 meters (6.6 feet) long.

Compared to other right whales in the Northern Hemisphere, a greater number of southern right whales have a pale coloring. Some of these whales remain white even as they grow older. The oldest known living southern right whale was 70 years old. However, a study from 2024 found that the average lifespan of these whales is about 73 years, and some individuals may live to be over 130 years old.

Behaviour

Southern right whales are often seen on the water's surface and are curious about human boats. They are more active and interact more with humans than the two northern right whale species. A unique behavior of southern right whales is called "tail sailing," where they lift their tail flukes to catch the wind and stay in one position for a long time. This behavior is believed to be a form of play and is most often seen near Argentina and South Africa. Other whale species, such as humpback whales, also show similar behaviors. Southern right whales frequently interact with other sea animals, including humpback whales and dolphins. There are reports of southern right whales and humpback whales possibly engaging in mating activities near Mozambique and along Bahia, Brazil.

A female southern right whale was seen near Western Australia with a lone humpback whale calf, though the connection between them is unknown. Southern right whales return to their calving areas every 3 years, though the time between calving can range from 2 to 21 years. Calving occurs between June and November in areas between 20 and 30° S. In Australia, southern right whales prefer calving areas with strong wave activity, such as the Head of the Bight. These waves may help hide the sounds of whales, protecting young calves and mothers from predators like killer whales. Deeper waters near calving areas may help calves build strength for migration.

Southern right whales reach sexual maturity between 3 and 6 years old. Female whales give birth to their first calf between 8 and 10 years old. A calf is born after one year of pregnancy, weighing about 1 short ton (0.91 t) and measuring 4–6 meters (13–20 feet) long. Calves stay with their mothers for the first year, growing to twice their length. A southern right whale with a genetic condition (XXY) has been recorded.

Southern right whales have been seen nursing unrelated calves on occasion. They have also been observed engaging in male-to-male contact, a behavior that may be related to socializing, play, or reducing tension between males.

The only known predator of southern right whales is the killer whale. In 1986, killer whales were seen hunting a southern right whale calf in Golfo San Jose, Argentina. In 2008, killer whales hunted a newborn southern right whale near Balneario Quintão, Brazil.

Like other right whales, southern right whales eat mostly zooplankton, especially krill. They swim just below the water's surface, keeping their mouths open to filter water through their long baleen plates. A southern right whale’s baleen can be up to 2.8 meters (9 feet 2 inches) long and consists of 220–260 baleen plates.

Population and distribution

The number of southern right whales in the world was estimated to be 13,611 in 2009. Earlier estimates, such as one from National Geographic in 2008, suggested about 10,000 whales, and a 1998 report from an IWC workshop estimated 7,000. Scientists used data from surveys of adult female whales in Argentina, South Africa, and Australia in the 1990s. They calculated the total population by estimating numbers in areas not surveyed and using known ratios of males to females and adults to calves. Scientists predict the population will reach less than half of its size before whaling began by 2100 because of past whaling and slower recovery. Since whaling stopped, the population has grown by about 7% each year.

Southern right whales spend summer in the Southern Ocean near Antarctica, feeding. They may also feed in temperate areas like near Buenos Aires. In winter, they migrate north to breed and can be seen along the coasts of Argentina, Australia, Brazil, Chile, Namibia, Mozambique, Peru, Tristan da Cunha, Uruguay, Madagascar, New Zealand, and South Africa. Some whales may also winter in sub-Antarctic regions. Southern right whales from South America, South Africa, and Australasia rarely mix because mothers and calves strongly prefer specific feeding and calving areas. This choice is passed from mother to calf.

Southern right whales usually do not cross the equator to breed with other groups because their thick blubber makes it hard to cool down in tropical waters. Historical records and some unconfirmed sightings suggest that E. australis may sometimes travel through equatorial waters. Whaling records include areas in the northern Indian Ocean and near-equatorial regions. If a sighting near Kiribati was confirmed as E. australis, this species may have crossed the equator occasionally, suggesting their historical range was larger and more northern than currently believed. A 21.3-meter (71-foot) whale stranded in India in 1944 was reported, but its species is uncertain.

Human activities and natural predators can affect where whales live. Many places in the Southern Hemisphere are named after southern right whales, such as Walvis Bay, Punta Ballena, Right Whale Bay, Otago Harbour, Whangarei Harbour, Foveaux Strait, South Taranaki Bight, Moutohora Island, and Wineglass Bay.

In South Africa, Hermanus is a famous whale-watching spot. During winter (June–October), southern right whales migrate to South African coasts, with over 100 visiting Hermanus. They come to Walker Bay to calve and mate. Behaviors like breaching, sailing, lobtailing, and spyhopping can be seen. In False Bay, whales are visible from July to October, and in Plettenberg Bay and Algoa Bay, they are present from July to December. They can be viewed from land or by boat with licensed guides.

Recent sightings in northeastern South Africa, such as near Ballito and Umdloti Beach, suggest whales are expanding their range and may return to historical habitats as more migrate north. In Namibia, most whales are found near Luderitz, with few moving north to areas like Walvis Bay. Before illegal hunting stopped, whales were rare along Namibian coasts. Calving was first confirmed in the 1980s.

Historical records suggest southern right whales once lived farther north along the coasts of northern Namibia and Angola. Whaling occurred off Gabon, such as near Cape Lopez, and some sightings have been reported. Small numbers of southern right whales are seen near Mozambique and Madagascar. Historically, large numbers were seen near Durban, Delagoa/Maputo Bay, Inhaca Island, Ponta do Ouro, and the Bazaruto Archipelago. The first sighting in Mozambique after whaling ended was in 1997. In recent years, more whales are calving in areas like Île Sainte-Marie and Antsiranana Bay in Madagascar. Rare sightings have been confirmed near Mayotte. Whales were historically hunted near Tanzania and may still be present near Zanzibar.

Illegal whaling by the USSR has slowed recovery of whale populations near Tristan da Cunha and Gough Island, reducing the number of visiting whales. Based on records and sightings, southern right whales may be seen as far north as Saint Helena and Ascension Island.

In Brazil, over 300 southern right whales have been identified through photos of their head callosities by the Brazilian Right Whale Project, a joint effort between Petrobras and the International Wildlife Coalition. Breeding and calving occur in Santa Catarina from June to November, and some females also calve near Argentina and Uruguay. However, fewer whales are visiting coastal areas in recent years, possibly due to human activities and conflicts with fisheries. Sightings outside Santa Catarina and Rio Grande do Sul are rare, such as near Cidreira, Rio de Janeiro, Sepetiba Bay, Cabo Frio, and other locations. Studies show fewer sightings along the coasts of São Paulo and Rio de Janeiro.

Further north, small numbers of southern right whales migrate to Bahia, especially the Abrolhos Archipelago, where some return every 3–4 years. Historical records show more whales were present near Salvador, Bahia.

Argentina has the largest breeding population of southern right whales at Península Valdés in Chubut province, where over 2,000 whales gather during breeding season. These whales are protected under Argentine law as a "natural monument."

Whaling

By 1750, the North Atlantic right whale was almost extinct for hunting and trade. American whalers then moved to the South Atlantic by the late 1700s. The farthest south Brazilian whaling station was built in 1796 in Imbituba. Over the next 100 years, American whaling expanded into the Southern and Pacific Oceans, where other European nations also joined.

Southern right whales had been traveling in large numbers to Australian and New Zealand waters before the 1800s. However, they were heavily hunted from 1800 to 1850. Hunting decreased as whale numbers dropped, and by the early 1900s, it had nearly stopped in coastal areas of Australia and New Zealand. Industrial whaling began in the early 1900s, and the number of whales caught increased quickly. By 1937, records showed 38,000 whales were harpooned in the South Atlantic, 39,000 in the South Pacific, and 1,300 in the Indian Ocean. These records were incomplete, so the actual number of whales taken was likely higher.

When it became clear that the whale population was nearly gone, hunting right whales was banned in 1937. This ban was mostly successful, though some illegal whaling continued for many years. Madeira caught its last two right whales in 1968. Illegal whaling also happened along Brazil’s coast for years, and the Imbituba station processed right whales until 1973. The USSR admitted to catching over 3,300 right whales illegally during the 1950s and 1960s, but only reported catching 4.

Illegal whaling continued into the 1970s, such as in Brazil until 1973. It was later discovered that Japan supported these hunts by ignoring its responsibility to monitor whaling activities. Japan and the Soviet Union agreed to hide their illegal whaling in protected international waters.

Right whales began returning to Australian and New Zealand waters in the early 1960s. If the Soviet hunts had not occurred, the New Zealand population might now be three to four times larger than it is today.

Conservation

The southern right whale is listed as "endangered" by CITES and is protected by all countries where it breeds (Argentina, Australia, Brazil, Chile, New Zealand, South Africa, and Uruguay). In Argentina, the whale is protected as a "Natural Monument" under national Law Number 23094, and all whales seen in Argentine waters are legally protected. In Brazil, a federal Environmental Protection Area covering about 1,560 kilometers (600 miles) of coastline and 130 kilometers (81 miles) of land in Santa Catarina State was created in 2000 to protect the whale's main breeding areas and support 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) because it is at risk of extinction in all or many parts of its habitat. It is also covered by the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MoU). In 2017, the IUCN Red List of Threatened Species listed the whale as "Least Concern," but the population trend was described as "unknown."

In Australia, southern right whales are protected under various state and federal laws, as shown in the table below.

A two-year project costing £740,000, led by the British Antarctic Survey and funded by the UK's Department for Environment, Food and Rural Affairs (Defra) and the EU, began in 2016. The project aims to investigate why nearly 500 young whales have washed up on the Valdes Peninsula over the past ten years. Possible reasons include a lack of krill in feeding areas near South Georgia and the South Sandwich Islands, exposure to toxic algae, and attacks by kelp gulls (Larus dominicanus).

Kelp gulls have been observed attacking live right whales since at least 1996, particularly targeting mother and calf pairs. The gulls use their strong beaks to bite into the whales' skin and blubber, causing large sores that can be up to half a meter wide. This behavior forces whales to spend much of their time avoiding gulls, reducing the time mothers spend nursing their calves. Researchers believe that waste from fish processing plants once supported large gull populations, but as waste decreased, gulls began targeting whales as an alternative food source. Scientists warn that this behavior may spread, and the IWC Scientific Committee has urged Brazil to act quickly if similar gull behavior is found in its waters. Possible actions include removing attacking gulls, as Argentina has done.

Southern right whales face threats from entanglement in fishing gear and collisions with ships. Fishing gear can cut into a whale's skin, causing infections, amputations, or death. Underwater noise from human activities, such as drilling and dredging, can disrupt whale communication and drive them away from their usual habitats and breeding areas.

Whale watching

The southern right whale has made Hermanus, South Africa, a worldwide center for whale watching. During the winter months (June to October), southern right whales swim very close to the shoreline, allowing visitors to see them from the shore or from specific hotels. The town uses a "whale crier" (similar to a town crier) to walk through the town and announce where whales are spotted. Hermanus also has two boat-based whale watching services. Southern right whales can also be seen from the shore or from boats in False Bay and Simon's Town. Plettenberg Bay, along the Garden Route in South Africa, is also known for whale watching, including both land and boat-based viewing, not only for southern right whales (July to December) but throughout the year. Southern right whales can also be seen off the coast of Port Elizabeth, where marine eco tours operate from the Port Elizabeth harbor, as some whales spend the winter months in Algoa Bay.

Southern right whales have been spotted in neighboring countries such as Namibia, Mozambique, and Madagascar, but they are not the main focus of whale watching tours in these areas.

In Brazil, Imbituba in Santa Catarina is recognized as the National Right Whale Capital and holds annual Right Whale Week celebrations in September, when mothers and calves are more commonly seen. The old whaling station there is now a museum that explains the history of right whales in Brazil. In Argentina, Península Valdés in Patagonia hosts the largest breeding population of southern right whales during the winter, with more than 2,000 whales cataloged by the Whale Conservation Institute and Ocean Alliance. In Puerto Madryn, the whales swim within 200 meters (660 feet) of the main beach and are part of a large ecotourism industry. In 2013, Uruguay's Parliament made all of its territorial waters a protected area for whales and dolphins. Every year, many whales are seen, especially in the regions of Maldonado and Rocha during winter. Swimming with whales for commercial purposes was banned in 1985 but was later allowed in the Gulf of San Matías, the only place in the world where humans are officially permitted to swim with the species. Land-based whale watching and occasional kayaking with whales occur in other areas, such as Puerto Deseado, Mar del Plata, and Miramar in Buenos Aires, where there are fewer restrictions on approaching whales.

Although their numbers are still very low, land-based sightings of southern right whales are increasing in recent years off the coasts of Chile and Peru, with hopes of developing new tourism industries, especially in the Strait of Magellan, particularly near Cape Virgenes.

In Australia's winter and spring, southern right whales migrate along the Great Australian Bight in South Australia. Popular viewing spots include the Bunda Cliffs and Twin Rocks, the Head of the Bight (which has a visitor center and cliff-top boardwalks), and Fowler's Bay, where accommodations and charter boat tours are available. Another popular location in South Australia is Encounter Bay, where the South Australian Whale Centre supports visitors. In Warrnambool, Victoria, a right whale nursery is a popular tourist attraction. The whales' migration range is expanding as the species recovers and returns to other areas of the continent, including the coastal waters of New South Wales and Tasmania. In Tasmania, the first birth since the 19th century was recorded in 2010 in the River Derwent.

In New Zealand, southern right whales are being seen more regularly from the shore than in the past, especially in southern Fiordland, Southland, and along the Otago coast, as well as on the North Island coast, particularly in Northland and other areas such as the Bay of Plenty and the South Taranaki Bight. While calf births may have occurred along the main islands' coasts, they were confirmed in 2012 with two cow-calf pairs observed.

In the Subantarctic Islands and near Antarctica, where few rules exist or are followed, whales can be seen on expedition tours with increasing frequency. The Auckland Islands are a protected sanctuary for right whales, where whale-watching tourism is not allowed without official permission.

Popular culture

The species was shown on a 70 p special stamp made by Tristan da Cunha in 2019 as part of a collection honoring various types of whales.