Southern right whale

Appearance

An adult female is 15 m (49 ft) and can weigh up to 47 tonnes (46 long tons; 52 short tons), with the larger records of 17.5–18 m (57–59 ft) in length and 80 tonnes (79 long tons; 88 short tons) or up to 90 tonnes (89 long tons; 99 short tons) in weight, making them slightly smaller than other right whales in the Northern Hemisphere. 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 do not normally cross the warm equatorial waters to connect with the other species and (inter)breed: their thick layers of insulating blubber make it difficult for them to dissipate their internal body heat in tropical waters. However, based on historical records and unconfirmed sightings in modern periods, E. australis actually do occur in equatorial waters.

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.

Distribution

The southern right whale spends summer in the far Southern Ocean feeding, probably close to Antarctica. If the opportunity arises, feeding can occur even in temperate waters such as along Buenos Aires. 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, however, whales have been known to winter on sub-Antarctic regions. 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. If the later mentioned sighting was truly of E. australis, this species could cross the Equator on irregular occasions.

The most recent population estimates, published by National Geographic in October 2008, put the southern whale population at 10,000. An 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.

Aside from impacts on whales and environments caused by mankind, their distributions and residences could be largely effected by presences of natural predators or enemies, and similar trends are also expectable for other subspecies.

Many locations throughout the Southern Hemisphere where whales are rare today were named after the former presence of southern rights, including Walvis Bay, Punta Ballena, Right Whale Bay, Otago Harbour, Whangarei Harbour, South Taranaki Bight, Moutohora Island and Wineglass Bay.

Status

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.

The southern right whale is covered by the Memorandum of Understanding for the Conservation of Cetaceans and Their Habitats in the Pacific Islands Region (Pacific Cetaceans MoU).

Behavior

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 behavior unique to the southern right whale, known as sailing, is that of using their elevated flukes to catch the wind, remaining in the same position for 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. Some other species such as humpback whales are also known to display. Right whales are often seen interacting with other cetaceans, especially humpback whales and dolphins. There is a record of a southern right and a humpback thought to be involved in mating activities off Mozambique.

They have very strong maternal connections with locations and gene pools they were born in, and they are known to return to their 'birth spots' at 3-years intervals. This species has been recognized to nurse unrelated orphans on occasions.

On occasions such as under attack by predators, right whales have been observed to perform the 'marguerite formation' like sperm whales.