Porbeagle

Porbeagle

Taxobox
name = Lamna Nasus
status = VU | status_system = IUCN3.1
trend = down



image_width = 200px
regnum = Animalia
phylum = Chordata
classis = Chondrichthyes
subclassis = Elasmobranchii
ordo = Lamniformes
familia = Lamnidae
genus = "Lamna"
species = "L. nasus"
range_


range_map_width = 200px
range_map_caption = Range of porbeagle (in blue)
binomial = "Lamna nasus"
binomial_authority = Bonnaterre, 1788
The porbeagle, "Lamna nasus", is a pelagic predatory shark of the family Lamnidae. The porbeagle is considered vulnerable to extinction, and the European Union has proposed listing the porbeagle under the United Nations Convention on International Trade in Endangered Species (CITES) [cite press release |title=More oceanic sharks added to the IUCN Red List |publisher=IUCN |date=2007-02-22 |url=http://www.iucn.org/en/news/archive/2007/02/22_pr_sharks.htm |format= |language= |accessdate=2007-02-25 |quote= ] .

Naming

The origins of the name porbeagle are unknown. The "Oxford English Dictionary" attributes its first appearance to a Cornish dialect. It is possible it is derived from two old French words meaning "hog" and "nose".cite book |last=Thrussell |first=Mike |title=First Run Shark |date=1990 |publisher=Ward Lock |id= ISBN 0-7063-6930-0] The Greek "lamna" means "shark" and "nasus" means "nose".

Distribution

The porbeagle's distribution ranges from the northeastern coast of North America, from New Jersey to Greenland and from the northwestern coast of Africa, Morocco or Western Sahara and the Mediterranean, and up to the waters off Iceland to the north coast of Norway and the northwestern coast of Russia. In the southern hemisphere its distribution is circumglobal from 30° to 60° south.

The porbeagle is listed as "Vulnerable" on the IUCN (World Conservation Union) Red List of Threatened Species. Canada also lists the porbeagle as an endangered species [cite web|url=http://www.speciesatrisk.gc.ca/search/speciesDetails_e.cfm?SpeciesID=810|title=Environment Canada: Species at risk|accessdate=2008-02-01] overfishing has recently decimated numbers in British waters.

Habitat

The porbeagle is mainly a pelagic shark, but can be found in coastal waters. It lives in cold water commonly from about 5°C to 10°C (41°F to 50°F), but have been found down to 1°C (33°F) and up to 23°C (71°F). It can be found at the surface and to a depth of more than 700 metres.

Anatomy and appearance

The most distinguishing characteristic of the porbeagle is a white patch on the trailing edge of the dorsal fin. This distinguishes it from all other sharks in its family. It has two keels on the caudal fin, in common with the salmon shark.

The porbeagle is a stout and heavy shark, dark blue-grey on top and white underneath, with a conical snout. The porbeagle can grow to about 3.7 m (12 ft), weighing about 160 to 250 kg (350 to 550 lb).

Behaviour

The porbeagle is among the fastest sharks. It can jump fully out of the water, a behavior observed in only a few sharks. Porbeagles are unique in that they have been known to play tag with other porbeagles, pass around seaweed to other porbeagles, and toss driftwood out of the water in a manner similar to dolphins.

Diet

The porbeagle is an opportunistic feeder, it eats mostly bony fish like mackerel, herring, lancetfish and sauries.

Reproduction

The porbeagle is ovoviviparous. Gestation period is about 8 to 9 months. Litters of up to 6 pups have been recorded but the normal size is about 4. Pups are about 60 to 80 cm long when born. Female porbeagles reaches sexual maturity at about 12 to 13 years and males at 7 to 8 years.

References

* Database entry includes a range map and justification for why this species is vulnerable
*
*

Footnotes

External links

* [http://www.postmodern.com/~fi/sharkpics/ellis/porbeagl.htm Richard Ellis porbeagle page]
* [http://new-brunswick.net/new-brunswick/sharks/species/porbeagle.html New brunswick net porbeagle page]
* [http://www.flmnh.ufl.edu/fish/Gallery/Descript/Porbeagle/Porbeagle.html Florida museum of natural history porbeagle page]
* [http://www.marinebiodiversity.ca/shark/english/porbeagle.htm Canadian Shark research laboratory]
* [http://www.newenglandsharks.com/porbeagl.htm Capt. Toms guide to New England sharks]
* [http://www.zoo.co.uk/~z9015043/porbeagle.html Mediterranean Shark site]
*


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Look at other dictionaries:

  • Porbeagle — Por bea gle, n. (Zo[ o]l.) A species of shark ({Lamna cornubica}), about eight feet long, having a pointed nose and a crescent shaped tail; called also {mackerel shark}. [Written {also probeagle}.] [1913 Webster] …   The Collaborative International Dictionary of English

  • porbeagle — [pôr′bē΄gəl] n. [< Cornish dial. porgh bugel] a large, fierce mackerel shark (Lamna nasus) of the N Atlantic, which brings forth living young …   English World dictionary

  • porbeagle shark — atlantinis silkiaryklis statusas T sritis zoologija | vardynas taksono rangas rūšis atitikmenys: lot. Lamna nasus angl. mackerel shark; porbeagle shark rus. атлантическая сельдевая акула; ламна ryšiai: platesnis terminas – paprastieji… …   Žuvų pavadinimų žodynas

  • porbeagle shark — noun see porbeagle …   Useful english dictionary

  • porbeagle — noun Etymology: Cornish porgh bugel Date: 1758 a viviparous mackerel shark (Lamna nasus) chiefly of the North Atlantic and southwestern Pacific oceans with a pointed snout and crescent shaped tail …   New Collegiate Dictionary

  • porbeagle — /pawr bee geuhl/, n. a shark of the genus Lamna, esp. L. nasus, a large, voracious species of the North Atlantic and North Pacific oceans. [1750 60; < Cornish porghbugel] * * *       species of mackerel shark (q.v.). * * * …   Universalium

  • porbeagle — noun A large pelagic predatory shark, Lamna nasus, of the Atlantic …   Wiktionary

  • porbeagle — shark with a pointed snout Unusual Animals …   Phrontistery dictionary

  • porbeagle — n. large shark with a pointed nose and a tail shaped like a crescent (found in the North Atlantic ocean and Mediterranean) …   English contemporary dictionary

  • porbeagle — [ pɔ:bi:g(ə)l] noun a large, active shark found chiefly in the open seas of the North Atlantic and in the Mediterranean. [Lamna nasus.] Origin C18: perh. from Cornish porth harbour, cove + bugel shepherd …   English new terms dictionary

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