Hooded Seal

Hooded Seal

Taxobox
name = Hooded SealMSW3 Wozencraft | pages = | id = 14001030]
status = LR/lc
status_system = iucn2.3
status_ref = IUCN2007 | assessors = Seal Specialist Group | year = 1996 | title = Cystophora cristata | id = 6204 | downloaded = 2008-05-18]



regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Carnivora
familia = Phocidae
genus = "Cystophora"
genus_authority = Nilsson, 1820
species = "C. cristata"
binomial = "Cystophora cristata"
binomial_authority = (Erxleben, 1777)
range_


range_map_caption = Distribution of the Hooded Seal. Breeding grounds indicated in blue.
The Hooded Seal ("Cystophora cristata") is an arctic pinniped found only in the central and western North Atlantic ranging from Svalbard in the east to the Gulf of St. Lawrence in the west.

Naming

The generic name means 'bladder-bearer' in Greek, from the peculiar inflatable appendage on the nose of the adult male. The seal is named after a cap-like bulge essay on the forehead and nose of the adult male which does not hang down, unlike that of the elephant seals.

The bulge

The bulge develops when the seal is four years old. The male can blow up this bulge, so that the size of its head seems to be twice as large. Very rarely the bulge can become infected and turn a bright red color.

ize

Adult males are m to ft|2.6|abbr=yes|precision=1 long on average, and weigh lb to kg|900|abbr=yes|precision=0. Sexual dimorphism is obvious from birth and females are much smaller: m to ft|2.03|abbr=yes|precision=1 long and rarely weighing kg to lb|300|abbr=yes|precision=0. The colour is silvery; the body is scattered with dark, irregular marks. The head is darker than the rest of the body, and without marks.

Lifestyle

In April through June, after the breeding season, this species travels long distances to feed and eventually gather together again in separate moulting areas on the ice from June through August. After moulting, it disperses widely again to feed in the late summer and autumn before returning to the breeding areas in late winter.

Breeding

There are four major breeding areas: the Gulf of St. Lawrence, the "Front" east of Newfoundland, Davis Strait (between Greenland and northern Canada) and the West Ice near Jan Mayen.

Offspring

Pups are about m to ft|1|abbr=yes|wiki=yes|precision=0 long at birth and weigh about kg to lb|24|abbr=yes|wiki=yes|precision=0. They are born on the ice from mid-March to early April with a well-developed blubber layer and having shed their pre-natal coat. They are born with a slate blue-grey coat (giving them the name "blueback"), with a pale cream color on the belly, which they will moult after about 14 months. Nursing of the pup lasts for an average of only 4 days, the shortest lactation period of any mammal, during which the pup doubles in size from about. This is possible because the milk that they drink has a fat content of 60%. [ [http://www.ncbi.nlm.nih.gov/sites/entrez?db=pubmed&uid=7601954&cmd=showdetailview&indexed=google Prenatal and postnatal transfer of fatty acids fro... [J Comp Physiol [B. 1995 - PubMed Result ] ] The female pup will mature between ages 3 and 6, whereas the male pup will mature between ages 5 and 7.

Lifespan

The Hooded Seal can live to about age 30 to 35.

References

External links

* [http://www.pinnipeds.org/species/hooded.htm SCS: Hooded Seal]
* [http://www.cresli.org/cresli/seals/hoodseal.html CRESLI hooded seal]


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Look at other dictionaries:

  • Hooded seal — Hooded seal[1] Conservation status …   Wikipedia

  • Hooded seal — Hooded Hood ed, a. 1. Covered with a hood. [1913 Webster] 2. Furnished with a hood or something like a hood. [1913 Webster] 3. Hood shaped; esp. (Bot.), rolled up like a cornet of paper; cuculate, as the spethe of the Indian turnip. [1913… …   The Collaborative International Dictionary of English

  • hooded seal — n. a large, dark gray, earless seal (Cystophora cristata) of the N Atlantic: the male has on its head a hoodlike sac that can be inflated …   English World dictionary

  • hooded seal — a large seal, Cystophora cristata, the male of which has a large, distensible, hoodlike sac on the head. Also called bladdernose. [1860 65] * * * ▪ mammal also called  bladdernose seal   large grayish seal with dark spots that is found in open… …   Universalium

  • hooded seal — pūsliasnukis ruonis statusas T sritis zoologija | vardynas taksono rangas rūšis atitikmenys: lot. Cystophora cristata angl. bladder nosed seal; crested seal; hooded seal vok. Blasenrobbe; Kappenrobbe; Klappmütze; Mützenrobbe rus. хохлач pranc.… …   Žinduolių pavadinimų žodynas

  • hooded seal — noun medium sized blackish grey seal with large inflatable sac on the head; of Arctic and northern Atlantic waters • Syn: ↑bladdernose, ↑Cystophora cristata • Hypernyms: ↑earless seal, ↑true seal, ↑hair seal • Member Holonyms: ↑ …   Useful english dictionary

  • hooded seal — hood′ed seal′ n. mam a large earless seal, Cystophora cristata: the male has a large, distensible, hoodlike sac on the head • Etymology: 1860–65 …   From formal English to slang

  • hooded seal — noun /ˈhʊdɪd siːl/ An arctic seal, Cystophora christata, notable for the fleshy bulge on its forehead and nose …   Wiktionary

  • hooded seal — noun a North Atlantic seal with a grey and white blotched coat, the male having a nasal sac that inflates into a hood during display. [Cystophora cristata.] …   English new terms dictionary

  • hooded seal — /hʊdəd ˈsil/ (say hooduhd seel) noun → bladdernose …  

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