Southern Right Whale, Hermanus, South Africa
| Eubalaena australis|
The right whales are marine mammals belonging to the family Balaenidae. There are four species in one genus - Eubalaena - three species of right whale (which are discussed below), and the Bowhead Whale.
|Table of contents|
4 Population and distribution
6 Whale watching
Right whales are easily distinguished from other whales by the large number of callositities on their heads, a thick back without a dorsal fin, and a long dropping mouth that begins high above the eye and the arches round beneath it. The body of the whale is very dark grey or black with some white patches, particularly on the belly. Right whales are slow swimmers but highly acrobatic and frequently breach (jump clear of the sea surface), tail-slap and lobtail. Females reach sexual maturity at 6-12 years and breed every 3-5 years. Calves are approximately 1 tonne in weight and 2-4 metres in length. Adults may be between 11-18 metres in length and up to 80 tonnes in weight. Right whales have between 250 and 350 baleen plates on each side of the mouth.
The taxonomy of the right whales has long been controversial. The Bowhead Whale is clearly an individual species and has always been recognised as such. However, different authorities have disagreed over whether to categorise the other right whales as a single worldwide species, 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. No group 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 interbred for between 3 million and 12 million years, confirming the status of the Southern Right Whale as a distinct species. More surprising has been the finding that the northern hemisphere Pacific and Atlantic populations are also distinct, and that the Pacific species (now known as the Pacific Northern Right Whale), is in fact more closely allied with the Southern Right Whale than with the Atlantic Northern Right Whale.
- ORDER CETACEA
- Suborder Mysticeti
- Family Eschrichtiidae: Gray Whale
- Family Balaenopteridae: Rorquals
- Family Balaenidae
- Atlantic Northern Right Whale, Eubalaena glacialis
- Pacific Northern Right Whale, Eubalaena japonica
- Southern Right Whale, Eubalaena australia
- Bowhead Whale, Eubalaena mysticetus
- Family Neobalaenidae: Pygmy Right Whale
- Suborder Odontoceti: 9 families
- Suborder Mysticeti
WhalingRight whales were named because whalers thought they were the 'right' whale to hunt, 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 only with 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 Atlantic population was commercially extinct. Exploitation of the Pacific and Southern Right Whales followed, and they too were on the brink of extinction by the early 1900s. A worldwide total ban on right whaling was agreed in 1937.
Population and distribution
There 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 been reported 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 to become extinct within 200 years ().
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 Whale ceased, stocks have estimated to have grown by only 7% in 60 years.
A report published in the Proceedings of the Royal Society B in December 2003 suggested that Northern Rights responded rapidly on hearing sounds similar to police sirens. On hearing the sounds they moved rapidly to the surface. The research was of particular interest because it is known that Northern Rights ignore most sounds, including those of approaching boats.
Southern Right Whales have made Hermanus, South Africa one of the world centres for whale watching. During the winter months (July-October) Southern Right Whales come 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 where whales have been seen. Southern Rights can also be watched at other winter breeding grounds.