Pygmy Right Whale
Encyclopedia
The pygmy right whale is a baleen whale
Baleen whale
The Baleen whales, also called whalebone whales or great whales, form the Mysticeti, one of two suborders of the Cetacea . Baleen whales are characterized by having baleen plates for filtering food from water, rather than having teeth. This distinguishes them from the other suborder of cetaceans,...

, the sole member of the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Neobalaenidae. First described by John Edward Gray
John Edward Gray
John Edward Gray, FRS was a British zoologist. He was the elder brother of George Robert Gray and son of the pharmacologist and botanist Samuel Frederick Gray ....

 in 1846, it is the smallest of the baleen whales, ranging between 6 metres (19.7 ft) and 6.5 metres (21.3 ft) in length and 3,000 and 3,500 kg in mass. Despite its name, the pygmy right whale may have more in common with the gray whale
Gray Whale
The gray whale, Eschrichtius robustus, is a baleen whale that migrates between feeding and breeding grounds yearly. It reaches a length of about , a weight of , and lives 50–70 years. The common name of the whale comes from the gray patches and white mottling on its dark skin. Gray whales were...

 and rorqual
Rorqual
Rorquals are the largest group of baleen whales, with nine species in two genera. They include the largest animal that has ever lived, the Blue Whale, which can reach , and another that easily reaches ; even the smallest of the group, the Northern Minke Whale, reaches .-Characteristics:Rorquals...

s than the bowhead
Bowhead Whale
The bowhead whale is a baleen whale of the right whale family Balaenidae in suborder Mysticeti. A stocky dark-colored whale without a dorsal fin, it can grow to in length. This thick-bodied species can weigh to , second only to the blue whale, although the bowhead's maximum length is less than...

 and right whale
Right whale
Right whales are three species of large baleen whales consisting of two genera in the family Balaenidae of order Cetacea. Their bodies are very dark gray or black and rotund....

s.

The pygmy right whale is found in the Southern Ocean
Southern Ocean
The Southern Ocean comprises the southernmost waters of the World Ocean, generally taken to be south of 60°S latitude and encircling Antarctica. It is usually regarded as the fourth-largest of the five principal oceanic divisions...

 in the lower reaches of the Southern Hemisphere
Southern Hemisphere
The Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...

, and feeds on copepod
Copepod
Copepods are a group of small crustaceans found in the sea and nearly every freshwater habitat. Some species are planktonic , some are benthic , and some continental species may live in limno-terrestrial habitats and other wet terrestrial places, such as swamps, under leaf fall in wet forests,...

s and euphausiids. Little is known about its population or social habits. Unlike most other baleen whales, it has rarely been subject to exploitation.

Taxonomy

During the 1839-43 voyage of James Clark Ross
James Clark Ross
Sir James Clark Ross , was a British naval officer and explorer. He explored the Arctic with his uncle Sir John Ross and Sir William Parry, and later led his own expedition to Antarctica.-Arctic explorer:...

 naturalists found bones and baleen plates resembling a smaller version of the right whale
Right whale
Right whales are three species of large baleen whales consisting of two genera in the family Balaenidae of order Cetacea. Their bodies are very dark gray or black and rotund....

. In his Zoology of the Voyage of HMS Erebus and Terror (1846), John Edward Gray
John Edward Gray
John Edward Gray, FRS was a British zoologist. He was the elder brother of George Robert Gray and son of the pharmacologist and botanist Samuel Frederick Gray ....

 described the new species, naming it Balaena marginata. In 1864 Gray established a new genus (Caperea) after receiving a skull and some bones of another specimen. Six years later, in 1870, he added the name Neobalaena. He soon realized the three species were one and the same: Caperea marginata (caperea means "wrinkle" in Latin, "referring to the wrinkled appearance of the ear bone"; while marginata translates to "enclosed with a border", which "refers to the dark border around the baleen plates of some individuals").

Description

The pygmy right whale is rarely encountered and consequently little studied. However, it is known that the pygmy right is by far the smallest of the baleen whales. Calves are estimated to be about 1.6 metres (5.2 ft) to 2.2 metres (7.2 ft) at birth (a 2 metres (6.6 ft) fetus was reported from a 6 metres (19.7 ft) female). By the time they are weaned they may be about 3 metres (9.8 ft) to 3.5 metres (11.5 ft) long. It is believed they become sexually mature at about 5 metres (16.4 ft) and physically mature at about 6 metres (19.7 ft). The longest male was a 6.1 metres (20 ft) individual which had stranded in Cloudy Bay, Tasmania, while the longest female was a 6.45 metres (21.2 ft) individual which had stranded in Stanley, Tasmania
Stanley, Tasmania
Stanley is a town on the north-west coast of Tasmania, Australia. Travelling west, Stanley is the second-last major township on the north-west coast of Tasmania, Smithton being the larger township in the Circular Head municipality...

. Pygmy rights can weigh as much as 3,430 kg—a 6.21 metres (20.4 ft) female weighed 3,200 kg and a 5.47 metres (17.9 ft) male weighed 2,850 kg. Gestation and lactation periods and longevity are all unknown. Part of the reason for the paucity of data may be the relative inactivity of the whale, making location for study difficult. The blow is small and indistinct and the whale is usually a slow undulating swimmer, although capable of bursts of acceleration.

The coloring and shape of the pygmy right whale, dark gray dorsally and lighter gray ventrally, commonly with a pair of chevron-shaped lighter patches behind the eyes, is similar to that of the dwarf minke and Antarctic minke whale
Antarctic Minke Whale
The Antarctic minke whale or southern minke whale , is a species of minke whale within the suborder of baleen whales.-Taxonomy:...

s and at sea may easily be confused with these two species if the jaw and flippers are not carefully observed. The arched jawline is not as pronounced as other right whale
Right whale
Right whales are three species of large baleen whales consisting of two genera in the family Balaenidae of order Cetacea. Their bodies are very dark gray or black and rotund....

s and may not be sufficient to distinguish a pygmy right whale from a minke whale. The long, narrow cream-coloured baleen plates with a distinctive white gumline are the most effective discriminators. Unlike true right whales, pygmy rights do not have callosities
Callosity
A callosity is another name for callus, a piece of skin that has become thickened as a result of repeated contact and friction.- Monkeys :When occurring on an animal's buttocks, as with baboons, they are specifically called ischial callosities...

. The dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...

 is falcate (crescent-shaped) and located about three-quarters of the way along the back of the animal. Unlike the minke whales, occasionally the dorsal will not be seen on the whale surfacing. Like the minkes, though, it doesn't raise its flukes when it dives.

Analysis of the stomach contents of dead pygmy right whales indicates that it feeds on copepods and euphausiids. The social and mating structures are unknown. The whale is typically seen alone or in pairs, sometimes associated with other cetaceans (including dolphins, pilot whale
Long-finned Pilot Whale
The long-finned pilot whale is one of the two species of cetacean in the genus Globicephala. It belongs to the oceanic dolphin family , though its behavior is closer to that of the larger whales.-Description:...

s, minke whale
Minke Whale
Minke whale , or lesser rorqual, is a name given to two species of marine mammal belonging to a clade within the suborder of baleen whales. The minke whale was given its official designation by Lacepède in 1804, who described a dwarf form of Balænoptera acuto-rostrata...

s, and once a sei whale
Sei Whale
The sei whale , Balaenoptera borealis, is a baleen whale, the third-largest rorqual after the blue whale and the fin whale. It inhabits most oceans and adjoining seas, and prefers deep offshore waters. It avoids polar and tropical waters and semi-enclosed bodies of water...

 cow and calf). Occasionally larger groups are seen — in 2001 a group of 14 were seen at 46°S in the South Pacific about 450 km southeast of New Zealand, while in 1992 a group of about 80 individuals were seen 320 nm southwest of Cape Leeuwin
Cape Leeuwin
Cape Leeuwin is the most south-westerly mainland point of the Australian Continent, in the state of Western Australia.A few small islands and rocks, the St Alouarn Islands, extend further to the south. The nearest settlement, north of the cape, is Augusta. South-east of Cape Leeuwin, the coast...

 and another group of over 100 individuals were sighted in June 2007 about 40 km southwest of Portland, Victoria
Portland, Victoria
The city of Portland is the oldest European settlement in what is now the state of Victoria, Australia. It is the main urban centre of the Shire of Glenelg. It is located on Portland Bay.-History:...

.

Population and distribution

The pygmy right whale is among the least studied cetaceans (as of 2008 fewer than 25 "at sea" sightings of the species have been made). The species lives in the Southern Hemisphere and is believed to be circumpolar
Circumpolar
The term circumpolar may refer to:* circumpolar navigation: to travel the world "vertically" traversing both of the poles* Antarctic region** Antarctic Circle** the Antarctic Circumpolar Current** Subantarctic** List of Antarctic and subantarctic islands...

, living in a band from about 30°S to 55°S in areas with surface water temperature between 5 and 20 °C (41 and 68 °F). Individuals have been found on the coasts of Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

, Tierra del Fuego
Tierra del Fuego
Tierra del Fuego is an archipelago off the southernmost tip of the South American mainland, across the Strait of Magellan. The archipelago consists of a main island Isla Grande de Tierra del Fuego divided between Chile and Argentina with an area of , and a group of smaller islands including Cape...

, Namibia
Namibia
Namibia, officially the Republic of Namibia , is a country in southern Africa whose western border is the Atlantic Ocean. It shares land borders with Angola and Zambia to the north, Botswana to the east and South Africa to the south and east. It gained independence from South Africa on 21 March...

, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 and New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...

. One group may be a year-round resident off Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...

. The total population is unknown.

Whaling and whale-watching

On account of its relatively small size and sparse distribution the pygmy right whale has rarely been taken by whalers. A 3.39 metres (11.1 ft) male was taken off South Africa in 1917, and it is likely that a few pygmy rights were taken opportunistically by whalers hunting minke whales. Also a few pygmy right whales are known to have been caught in fishing nets. However these factors are not believed to have had a significant impact on the population.

Most data about pygmy right whales come from individual specimens washed up on coastlines; they are rarely encountered at sea and so they are not the primary subject of any whale watching
Whale watching
Whale watching is the practice of observing whales and other cetaceans in their natural habitat. Whales are watched most commonly for recreation but the activity can also serve scientific or educational purposes. A 2009 study, prepared for IFAW, estimated that 13 million people went whale watching...

cruises.

Conservation

The Pygmy right whale is listed on Appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). It is listed on Appendix II as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements.

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

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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