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Atlantic Northern Right Whale(atlanticnorthernrightwhale,atlanticnorthern right whale,atlantic northernright whale,atlantic northern rightwhale)
The right whales are marine mammals belonging to thefamily Balaenidae. There are four species in one genus - Eubalaena - three species of right whale (which are discussedbelow), and the Bowhead Whale .
TaxonomyThe taxonomy of the right whales has long been controversial. The Bowhead Whale is clearly an individual species and has always been recognised assuch. However, different authorities have disagreed over whether to categorise the other right whales as a single worldwidespecies, as two species (one found only in the northern hemisphere, the other found in the Southern Ocean ), or as three species (splitting the northern species into Pacific and Atlantic populations).Small differences in the skull shape of northern and southern animals have tended to lend support to the two-species view. Nogroup of right whales has been known to swim through warm equatorial waters to make contact with the other (sub)species and(inter)breed. In recent years, genetic studies have provided clear evidence that the northern and southern populations have not interbredfor between 3 million and 12 million years, confirming the status of the Southern Right Whale as a distinct species. Moresurprising has been the finding that the northern hemisphere Pacific and Atlantic populations are also distinct, and that thePacific species (now known as the Pacific Northern Right Whale), is in fact more closely allied with the Southern Right Whalethan with the Atlantic Northern Right Whale.
Other namesDue to their familiarity to whalers over a number of centuries the right whales have been given many names over the years.They reflect the fact that it is only in recent times that two species have been distinguished. In his novel Moby Dick , HermanMelville writes: "Among the fishermen, [the whale regularly hunted for oil] isindiscriminately designated by all the following titles: The Whale; the Greenland Whale; the BlackWhale; the Great Whale; the True Whale; the Right Whale." Physical descriptionRight whales are easily distinguished from other whales by the large number of callositities on their heads, a thick backwithout a dorsal fin, and a long dropping mouth that begins high above the eye and the arches round beneath it. The body of thewhale is very dark grey or black with some white patches, particularly on the belly. Right whales are slow swimmers but highlyacrobatic and frequently breach (jump clear of the sea surface), tail-slap and lobtail. Females reach sexual maturity at 6-12years and breed every 3-5 years. Calves are approximately 1 tonne in weight and 2-4 metres in length. Adults may be between 11-18metres in length and up to 80 tonnes in weight. Right whales have between 250 and 350 baleen plates on each side of the mouth. WhalingRight whales were named because whalers thought they were the 'right' whale tohunt, for several reasons. Most importantly, 40% of a right whale's body weight is blubber (which is of relatively low density).In consequence, unlike other whales, right whales float when they die, which made them easy to catch, even for men equipped onlywith frail wooden boats and hand-held harpoons. Hunting of right whales began as early as the 11th century in the Bay of Biscay , and continued throughout the centuries until the Atlanticpopulation was commercially extinct. Exploitation of the Pacific and Southern Right Whales followed, and they too were on thebrink of extinction by the early 1900s. A worldwide total ban on right whaling was agreed in 1937 . Population and distributionThere are about 300 Atlantic Northern Right Whales, almost all living in the west North Atlantic , feeding in areas off the Canadian and US coasts. Sightings as far east as Iceland have beenreported in 2003. A small population probably exists in the north Pacific. The Northern Right Whales are the most endangered of all large whales and two of the most endangered animals in the world. Based on current population density trends the species is predicted tobecome extinct within 200 years ( [1] ). Southern Rights spend the summer months in the Southern Ocean feeding, probably close to Antarctica . Animals migrate north in winter for breeding and can be seen around the coasts of Chile , Argentina , South Africa , Australia and New Zealand . The total population is estimated to be 6-7,000. Since hunting of the Southern Right Whaleceased, stocks have estimated to have grown by only 7% in 60 years. However the IUCN liststhe species as lower risk; conservation dependent in their Red List of Threatened Species . HearingA report published in the Proceedings of the Royal Society B in December 2003 suggested that Northern Rights responded rapidlyon hearing sounds similar to police sirens. On hearing the sounds they moved rapidly to the surface. The research was ofparticular interest because it is known that Northern Rights ignore most sounds, including those of approaching boats. Whale watchingSouthern Right Whales have made Hermanus , South Africa one of the world centres for whale watching . During the winter months (July-October) Southern Right Whalescome so close to the Cape shoreline that visitors can watch whales from their (deliberately placed) hotels. The town employs a'whale crier' (c.f. town crier ) to walk through the town announcing wherewhales have been seen. Southern Rights can also be watched at other winter breeding grounds. ConservationThe particular vulnerabilility of the Northern Right Whale, which migrates through some of the world's busiest shipping laneswhilst journeying off the east coast of the United States, to collisions with ships led the National Oceanic and AtmosphericAdministration to propose new guidelines for captains of vessels in the area in June 2004. The guidelines, currently open topublic consultation, proposed a raft of measure restricting where ships could travel, and at what speed they can move in commonright whale feeding areas. Source: PRNewswire report through Yahoo! : [2] References
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