Bottlenose whale

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Bottlenose whales
Size comparison of a Northern Bottlenose Whale against an average human
Size comparison of a Northern Bottlenose Whale against an average human
Conservation status
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Cetacea
Suborder: Odontoceti
Family: Ziphidae
Genus: Hyperoodon
Lacépède, 1804
Species: H. planifrons
H. ampullatus
Binomial name
Hyperoodon ampullatus
(Forster, 1770)
Northern Bottlenose Whale range
Northern Bottlenose Whale range
Hyperoodon planifrons
Flower, 1882
Southern Bottlenose Whale range
Southern Bottlenose Whale range

A bottlenose whale is one of two species of whale in the Ziphiid family. The two species - the Northern Bottlenose Whale Hyperoodon ampullatus and the Southern Bottlenose Whale Hyperoodon planifrons are the sole members of the Hyperoodon genus. Whilst the two species are physically similar their stories over the past two hundred years are rather different. The Southern Bottlenose has been rarely observed, was seldomly hunted, and is probably the most abundant whale in Antarctic waters. The northern species on the other hand was hunted heavily by Norway and Britain in the nineteenth and early twentieth century. Norway finally stopped hunting the whale in 1973.

Contents

[edit] Physical description

The two species are long (8-10 m in length when adult) and fairly rotund. The melon is extremely bluff - the shape is similar to that of a caricatured 'egg-head' professor. The beak is long and is coloured white in males and grey in females. The dorsal fin is relatively small, 30-38 cm, set behind the middle of the back, is falcate and is usually tipped. The back is coloured mid-dark grey in the Northern species and light-to-mid grey in the Southern. Both species have a lighter underside. Weight estimates are hard to come by. For the Northern Bottlenose Whale, 5,800-7,500 kg is given somewhat consistently[1][2]. For the Southern Bottlenose Whale, there is a single figure of 6-8 tonnes[3].

[edit] Population and distribution

The Northern Bottlenose Whale is endemic to the North Atlantic Ocean and occurs in cool and subarctic waters. It is found in the Davis Strait, the Labrador Sea, the Greenland Sea and the Barents Sea. They prefer deep water. Total population is unknown but likely to be of the order of 10,000. "The Gully", a huge submarine canyon east of Nova Scotia has a year-round population of around 130.

The Southern Bottlenose Whale has a circumpolar distribution in the Southern Ocean. It is found as far south as the Antarctic coast and as north as the tip of South Africa, New Zealand's North Island and the southern parts of Brazil. There is thought to be a global population in excess of 500,000.

Sightings of an apparent Bottlenose Whale in tropical and subtropical waters probably belong to a poorly known species, Longman's Beaked Whale. The relationship of this species to other beaked whales has not been established.

There are many ways to tell the difference of males and females besides checking the underside. The males are normally a dark gray or black, and the females and calves are a white or very light gray.

On 20 January 2006, a Northern Bottlenose Whale was spotted in Central London in the River Thames [3]. The River Thames whale reached as far up river as Albert Bridge. It was moved onto a barge and rescuers hoped to take it out to sea, but it died following a convulsion on 21 January, during its rescue and it's skeleton is now in the Natural History Museum in London[4].

[edit] Conservation

The Southern Bottlenose Whale is not believed to be threatened by human actions. The species has seldomly been hunted (forty-two were caught in the Antarctic by Soviet whalers between 1970 and 1982).

Prior to the beginning of whaling of Northern Bottlenoses it is estimated that there were 40,000-50,000 individuals in the Atlantic. Between 1850 and 1973 88,000 individuals were killed, primarily by Norwegian and British whalers. The population is very likely to be much reduced on pre-whaling figures. Since whaling ended the primary concern to conservationists is the number of oil and gas developments around the Gully.

The Northern Bottlenose Whale in Nes near Hvalba
The Northern Bottlenose Whale in Nes near Hvalba

The Northern Bottlenose Whales are well-known in the Faroe Islands, mainly because in September each year they are killed, especially in the villages of Hvalba and Sandvík on Suðuroy.

[edit] References

  1. Bottlenose Whales in the Encyclopedia of Marine Mammals Shannon Gowans, 1998. ISBN 0-12-551340-2
  2. National Audubon Society Guide to Marine Mammals of the World Reeves et al, 2002. ISBN 0-375-41141-0.
  3. Whales, Dolphins and Porpoises Carwardine, 1995. ISBN 0-7513-2781-6

[edit] External links