Otter
46916
225271038
2008-07-12T20:28:13Z
201.74.102.140
/* Cultural references */
{{otheruses1|the carnivorous mammals}}
{{Taxobox
| name = Otters
| image = LutraCanadensis fullres.jpg
| image_width = 299px
| image_caption = [[Northern river otter]]s
| regnum = [[Animal]]ia
| phylum = [[Chordata]]
| classis = [[Mammal]]ia
| ordo = [[Carnivora]]
| familia = [[Mustelidae]]
| subfamilia = '''Lutrinae'''
| subdivision_ranks = Genera
| subdivision =
''[[Amblonyx]]''<br />
''[[Aonyx]]''<br />
''[[Enhydra]]''<br />
''[[Lontra]]''<br />
''[[Lutra]]''<br />
''[[Lutrogale]]''<br />
''[[Pteronura]]''
}}
'''Otters''' are [[wikt:amphibious|amphibious]] (or in one case [[aquatic animal|aquatic]]) fish-eating [[mammal]]s. The otter [[Rank (zoology)|subfamily]] ''Lutrinae'' forms part of the [[Family (biology)|family]] [[Mustelidae]], which also includes [[weasel]]s, [[polecat]]s, [[badger]]s, as well as others. With thirteen [[species]] in seven [[genus|genera]], otters have an almost worldwide distribution.They eat mainly fish, clams, lobsters, shrimp, and mice if they have to.
==Etymology and terminology==
The word ''otter'' derives from the [[Old English language|Old English]] word ''otr'', ''otor'' or ''oter''. This and cognate words in other [[Indo-European languages]] ultimately stem from a [[root (linguistics)|root]] which also gave rise to the English words ''water'', ''wet'' and ''winter''.
An otter's den is called a ''holt''. Male otters are ''dog-otters'', females are ''queens'' and babies are ''cubs'' or ''pups''. The [[collective noun]] ''pack'' or "romp" is sometimes used for a group of otters, being descriptive of their often playful nature.<ref>{{cite journal | month=July/August | year=2004 | title=Birds of a feather... | journal=Natural History | volume=113 | issue=6 | pages=71 | url=http://findarticles.com/p/articles/mi_m1134/is_6_113/ai_n6211593 | accessdate=2006-12-07}}</ref>
==Characteristics==
Otters have long, slim bodies and relatively short limbs, with webbed paws. Most have sharp claws on their feet, and all have long muscular tails.
They have a very soft underfur which is protected by their outer layer of long guard hair. This traps a layer of air, and keeps them dry and warm under water.
==Diet and behaviour==
Otters do not depend on their specialized fur alone for survival in the cold waters where many live: they also have very high [[metabolic rate]]s. For example [[#Eurasian otter|Eurasian otters]] must eat 15% of their body-weight a day, and sea otters, 20 to 25%, depending on the temperature. In water as warm as 10°C (50°F) an otter needs to catch 100 grams (3 oz) of fish per hour to survive. Most species hunt for 3 to 5 hours a day, and nursing mothers up to 8 hours a day.
Most otters have [[fish]] as the primary item in their diet, supplemented by [[frog]]s, [[crayfish]] and [[crab]]s. Some are expert at opening [[shellfish]], and others will take any available small mammals or birds. This prey-dependence leaves otters very vulnerable to prey depletion.
Otters are very active, chasing prey in the water or searching the beds of rivers, lakes or the sea. Most species live beside water, entering it mainly to hunt or travel, otherwise spending much of their time on land to avoid their fur becoming waterlogged. The sea otter actually lives in the sea.
Otters are playful animals, for example sliding repeatedly down snowy slopes, apparently from sheer enjoyment. Different species vary in their social structure, with some being largely solitary, while others live in groups—in a few species these groups may be fairly large.
==Species==
<div class="thumb tright" style="border: 1px solid #CCCCCC; margin:0.5em;">
{|border="0" cellpadding="2" cellspacing="0"
|{{clade| style=font-size:75%;line-height:75%
| label1=Lutrinae
| 1={{clade
| 1=[[Giant otter]] (''Pteronura brasiliensis'')
| 2={{clade
| 1={{clade
| 1=[[Northern river otter]] (''Lontra canadensis'')
| 2={{clade
| 1={{clade
| 1=[[Marine otter]] (''Lontra felina'')
| 2=[[Southern river otter]] (''Lontra provocax'')
}}
| 2=[[Neotropical river otter]] (''Lontra longicaudis'')
}} }}
| 2={{clade
| 1=[[Sea otter]] (''Enhydra lutris'')
| 2=[[Speckle-throated otter]] (''Hydrictis maculicollis'')
| 3={{clade
| 1={{clade
| 1=[[Eurasian otter]] (''Lutra lutra'')
| 2=[[Hairy-nosed otter]] (''Lutra sumatrana'')
}}
| 2={{clade
| 1={{clade
| 1=[[African clawless otter]] (''Aonyx capensis'')
| 2=[[Congo clawless otter]] (''Aonyx congicus'')
}}
| 2={{clade
| 1=[[Oriental small-clawed otter]] (''Aonyx cinerea'')
| 2=[[Smooth-coated otter]] (''Lutrogale perspicillata'')
}} }} }} }} }} }} }}
|}
<div style="border: none;"><div class="thumbcaption"><center><small>Cladogram, after Koepfli ''et al'' 2008<ref>{{cite journal |author=Koepfli KP, Deere KA, Slater GJ, ''et al'' |title=Multigene phylogeny of the Mustelidae: resolving relationships, tempo and biogeographic history of a mammalian adaptive radiation |journal=BMC Biol. |volume=6 |issue=1 |pages=4–5 |year=2008 |pmid=18275614 |doi=10.1186/1741-7007-6-10}}</ref> and Bininda-Emonds ''et al'' 1999<ref>{{cite journal |author=Bininda-Emonds OR, Gittleman JL, Purvis A |title=Building large trees by combining phylogenetic information: a complete phylogeny of the extant Carnivora (Mammalia) |journal=Biol Rev Camb Philos Soc |volume=74 |issue=2 |pages=143–75 |year=1999 |pmid=10396181 |doi=10.1017/S0006323199005307}}</ref></small></center></div></div></div>
Genus ''[[Lutra]] ''
*[[Eurasian otter]] (''Lutra lutra'')
*[[Hairy-nosed otter]] (''Lutra sumatrana'')
Genus ''[[Hydrictis]]''
*[[Speckle-throated otter]] (''Hydrictis maculicollis'')
Genus ''[[Lutrogale]]''
*[[Smooth-coated otter]] (''Lutrogale perspicillata'')
Genus ''[[Lontra]]''
*[[Northern river otter]] (''Lontra canadensis'')
*[[Southern river otter]] (''Lontra provocax'')
*[[Neotropical river otter]] (''Lontra longicaudis'')
*[[Marine otter]] (''Lontra felina'')
Genus ''[[Pteronura]]''
*[[Giant otter]] (''Pteronura brasiliensis'')
Genus ''[[Aonyx]]''
*[[African clawless otter]] (''Aonyx capensis'')
*[[Congo clawless otter]] (''Aonyx congicus'')
*[[Oriental small-clawed otter]] (''Aonyx cinerea'')
Genus ''[[Enhydra]]''
*[[Sea otter]] (''Enhydra lutris'')
=== Northern river otter ===
{{main|Northern river otter}}
The northern river otter (''Lontra canadensis'') became one of the major animals hunted and trapped for [[fur]] in North America after European contact. River otters eat a variety of fish and shellfish, as well as small land mammals and [[bird]]s. They grow to one metre (3 to 4 ft) in length and weigh from five to fifteen kilograms (10 to 30 lb).
In some areas this is a protected species, and some places have otter sanctuaries, which help ill and injured otters to recover.
===Sea otter===
[[Image:Sea otter cropped.jpg|thumb|200px|A sea otter in [[Morro Bay]], California]]
{{main|Sea otter}}
Sea otters (''Enhydra lutris'') live along the [[Pacific]] coast of North America. Their historic range included shallow waters of the [[Bering Strait]] and [[Kamchatka Peninsula|Kamchatka]], and as far south as Japan. Sea otters have some 200 thousand strands of [[hair]] per square centimetre of [[skin]], a rich fur for which humans hunted them almost to extinction. By the time the 1911 Fur Seal Treaty gave them protection, so few sea otters remained that the fur trade had become unprofitable.
Sea otters eat shellfish and other [[invertebrate]]s (especially [[clam]]s, [[abalone]], and [[sea urchin]]s ), frequently using rocks as crude [[tool]]s to smash open [[Animal shell|shell]]s. They grow to 1.0 to 1.5 metres (2.5<!-- ≠ 1 m --> to 5 ft) in length and weigh 30 kilograms (65 lb). Although once near extinction, they have begun to spread again, from remnant populations in [[California]] and [[Alaska]].
Unlike most marine mammals (such as [[Pinniped|seals]] or [[whale]]s), sea otters do not have a layer of insulating [[blubber]]. As with other species of otter, they rely on a layer of air trapped in their fur, which they keep topped up by blowing into the fur from their mouths. They spend most of their time in the water, whereas other otters spend much of their time on land.
=== Eurasian otter ===
[[Image:Otter in Southwold.jpg|thumb|200px|Eurasian otter, in England]]
{{main|Eurasian otter}}
This species (''Lutra lutra'') inhabits Europe, and its range also extends across most of [[Asia]] and parts of [[North Africa]]. In the [[British Isles]] they occurred commonly as recently as the 1950s, but became rare in many areas due to the use of [[chlorinated hydrocarbon]] [[pesticide]]s and as a result of [[Habitat (ecology)|habitat]]-loss and water [[pollution]] (they remained relatively common in parts of Scotland and Ireland). Population levels attained a low point in the 1980s, but are now recovering strongly. The UK [[Biodiversity Action Plan]] envisages the re-establishment of otters by 2010 in all the UK rivers and coastal areas that they inhabited in 1960. [[Roadkill]] deaths have become one of the significant threats to the success of their re-establishment.
=== Giant otter ===
[[Image:giantotter.jpg|thumb|200px|Giant otter]]
{{main|Giant otter}}
The giant otter (''Pteronura brasiliensis'') inhabits South America, especially the Amazon river basin, but is becoming increasingly rare due to poaching, habitat loss, and the use of mercury and other toxins in illegal alluvial gold mining. This gregarious animal grows to a length of up to 1.8 metres (6 ft), and is more aquatic than most other otters.
==Cultural references==
[[Norse mythology]] tells of the [[Norse dwarves|dwarf]] [[Ótr]] habitually taking the form of an otter. The myth of ''Otter's Ransom''<ref>{{Cite web
| title = The Otter's Ransom| accessdate = 2007-07-05| url = http://faculty.mcla.edu/cthomas/otter.html}}</ref> is the starting point of the [[Volsunga saga]].
In some Native American cultures, otters are considered [[totem animals]].
The otter is held to be a clean animal belonging to [[Ahura Mazda]] in [[Zoroastrianism|Zoroastrian]] belief, and taboo to kill.<ref name = "Cooper92">{{cite book |last=Cooper |first=JC |title=Symbolic and Mythological Animals |pages=p. 171-72|year=1992 |publisher= Aquarian Press |location=London |isbn=1-85538-118-4}}</ref>
In the [[Harry Potter]] books, [[Hermione Granger]]'s [[Spells in Harry Potter#Expecto Patronum (Patronus Charm)|Patronus]] is an otter.
==Gallery==
<gallery>
Image:Amblonyx_cinereus.jpg| Oriental small-clawed otter
Image:Lutra_longicaudis.jpg|Long-tailed otter in Tortuguero, Costa Rica
Image:Otters.jpg|otters at the Perth Zoo, Western Australia
Image:Fischotter, Lutra Lutra.JPG|Eurasian otter
</gallery>
==References and further reading==
{{wikispecies|lutrinae}}
{{commonscat|Lutrinae}}
{{reflist}}
{{refbegin}}
*Gallant, D., L. Vasseur, & C.H. Bérubé (2007). Unveiling the limitations of scat surveys to monitor social species: a case study on river otters. [http://www.wildlifejournals.org/perlserv/?request=get-abstract&doi=10.2193%2F2005-697 Journal of Wildlife Management] 71:258–265.
{{refend}}
==External links==
*[http://www.arkive.org/species/ARK/mammals/Lutra_lutra/ ARKive] Photographs and Videos of Eurasian Otter. On the same site are photos and videos of Marine otter (''Lontra felina''), Sea otter (''Enhydra lutris''), Marine otter (''Lontra felina'') , Sea otter (''Enhydra lutris''), Smooth-coated otter (''Lutrogale perspicillata'') and the Giant otter (''Pteronura brasiliensis'').
*[http://www.ottertrust.org.uk The Otter Trust]
*[http://www.otter.org/ International Otter Survival Fund]
*[http://www.otternet.com/index.htm Otternet]
*[http://www.chattoogariver.org/index.php?req=otter&quart=Sp2004 North American River Otter]
{{Mustelidae nav}}
[[Category:Carnivores]]
[[Category:Otters| ]]
[[Category:Mammals of North America]]
[[Category:Mammals of South America]]
[[Category:Mammals of Africa]]
[[Category:Mammals of Europe]]
[[Category:Mammals of Asia]]
[[ast:Llóndriga]]
[[ca:Llúdriga]]
[[cy:Dwrgi]]
[[da:Oddere]]
[[de:Otter]]
[[es:Lutrinae]]
[[eo:Lutro]]
[[fa:سمور آبی]]
[[fr:Loutre]]
[[fur:Lodre]]
[[ga:Dobharchú]]
[[gl:Lontra]]
[[ko:수달아과]]
[[hr:Vidre]]
[[io:Lutro]]
[[it:Lutrinae]]
[[la:Lutrinae]]
[[nah:Āhuitzotl]]
[[nl:Otters]]
[[cr:ᓂᒋᒄ]]
[[ja:カワウソ]]
[[pl:Wydry]]
[[pt:Lontra]]
[[ru:Выдровые]]
[[simple:Otter]]
[[fi:Saukot]]
[[th:นาก]]
[[vi:Rái cá]]
[[tr:Susamuru]]
[[zh:水獺]]