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American Beaver

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+#REDIRECT [[American Beaver]]
-{{Taxobox
-| name = American Beaver
-| status = LR/lc
-| status_system = iucn2.3
-| image = Castor canadensis.jpg
-| image_width = 250px
-| regnum = [[Animal]]ia
-| phylum = [[Chordata]]
-| classis = [[Mammal]]ia
-| ordo = [[Rodent]]ia
-| familia = [[Castoridae]]
-| genus = ''[[Beaver|Castor]]''
-| species = '''''C. canadensis'''''
-| binomial = ''Castor canadensis''
-| binomial_authority = [[Heinrich Kuhl|Kuhl]], 1820
-| subdivision_ranks = [[Subspecies]]<ref name="msw">[http://nmnhgoph.si.edu/cgi-bin/wdb/msw/synonyms/query/4013 MSW Synonym List.] ''Mammal Species of the World.'' Smithsonian Institution, 1993.</ref><ref name="warner">Warner, Richard E. and Kathleen M. Hendrix, editors. [http://content.cdlib.org/xtf/view?docId=ft1c6003wp&doc.view=content&chunk.id=d0e108057 California Riparian Systems: Ecology, Conservation, and Productive Management] University of California Press, 1984, p. 952. Retrieved on [[2007]]-[[08-04]].</ref><ref>[http://bnhm.berkeley.edu/browse/vertebrates_Mammalia_Rodentia_Castoridae_Castor_all.php?ViewResults=vertebrates_Mammalia_Rodentia_Castoridae_Castor_all  Browse Genus equals Castor by Scientific Name for All Museums]. Berkeley Natural History Museums. Retrieved on [[2007]]-[[08-04]].</ref><ref>Tesky, Julie L. [http://www.fs.fed.us/database/feis/animals/mammal/caca/all.html Wildlife Species: Castor canadensis] Fire Effects Information System (Online), U.S. Department of Agriculture, Forest Service,
-[[Rocky Mountain Research Station]], Fire Sciences Laboratory. 1993. Retrieved on [[2007]]-[[08-04]].</ref>
-| subdivision =
-* ''C. c. acadicus'' Bailey
-* ''C. c. baileyi'' Nelson
-* ''C. c. belugae'' Taylor<br/><small>Cook Inlet beaver</small>
-* ''C. c. caecator'' Bangs<br/><small>Newfoundland beaver</small>
-* ''C. c. canadensis'' Kuhl<br/><small>Canadian beaver</small>
-* ''C. c. concisor''
-* ''C. c. carolinensis'' Rhoads<br/><small>Carolina beaver</small>
-* ''C. c. duchesnei''
-* ''C. c. frondator'' Mearns<br/><small>Sonora beaver</small>
-* ''C. c. idoneus''
-* ''C. c. labradorensis''
-* ''C. c. leucodonta'' Gray<br/><small>Pacific beaver</small>
-* ''C. c. mexicanus'' Bailey<br/><small>Rio Grande beaver</small>
-* ''C. c. michiganensis'' Bailey<br/><small>Woods beaver</small>
-* ''C. c. missouriensis'' Bailey<br/><small>Missouri River beaver</small>
-* ''C. c. pacificus'' Rhoads<br/><small>Washington beaver</small>
-* ''C. c. pallidus''
-* ''C. c. phaeus'' Heller<br/><small>Admiralty beaver</small>
-* ''C. c. rostralis''
-* ''C. c. repentinus'' Goldman<br/><small>Sonora beaver</small>
-* ''C. c. taylori'' Davis
-* ''C. c. texensis'' Bailey<br/><small>Texas beaver</small>
-* ''C. c. subauratus''<br/><small>Golden beaver</small>
-* ''C. c. sagittatus''
-* ''C. c. shastensis'' Taylor<br/><small>Shasta beaver</small>
-}}
-The '''American Beaver''' (''Castor canadensis'') is a large semi-aquatic [[rodent]] native to [[Canada]], much of the [[United States]], and parts of northern [[Mexico]]. It was introduced in the most southern province of [[Argentina]], [[Tierra del Fuego]], and it adapted to its temperate forests many years ago. Common names include '''North American Beaver''', or simply '''Beaver''' in North America, as well as its subspecies names, the most common being the '''Canadian Beaver'''.
-== Description ==
-Its fur has a range of many different colors but is usually seen as dark brown. The beaver coat comprises two types of hair.  The outer section is coarse and long and covers an inner layer which is much finer.  It has a rounded head, a large flat paddle-shaped tail and webbed hind feet. The unwebbed front paws are smaller, with claws. This is the largest rodent found in [[North America]] and the second largest rodent in the world (the largest rodent being the [[South America]]n [[capybara]]).
-Beavers are mainly active at night. They are excellent swimmers but are more vulnerable on land and tend to remain in the water as much as possible. They are able to remain submerged for up to 15 minutes. A scent gland near their genitals secretes an oily substance known as castoreum which is used to waterproof its fur. A thick layer of fat under its skin insulates the beaver from its cold water environment. The eyes are covered by a [[nictitating membrane]] which allows the beaver to see underwater. Their nostrils and ears are sealed while submerged.  The flat, scaly tail is used to signal danger and also serves as a source of fat storage.
-They construct their homes, or "lodges," out of sticks, twigs, and mud in lakes or streams. These lodges may be surrounded by water, or touching land, including burrows dug into river banks. They are well known for building [[dam]]s across streams and constructing their lodge in the artificial pond which forms. The entrance to the lodge or burrow is located underwater. In the event of danger, a beaver slaps its tail on the water to warn other family members.
-The dam is constructed using sections of [[deciduous]] trees, especially [[birch]], [[aspen]], [[willow]] and [[poplar]]. The inner bark, twigs, shoots and leaves of such trees are also an important part of the beaver's diet. The trees are cut down using their strong [[incisor]] teeth. Their front paws are used for digging and carrying and placing materials.  Some researchers have shown that the sound of running water dictates when and where a beaver builds its dam. Besides providing a safe home for the beaver, beaver ponds also provide habitat for waterfowl and other aquatic animals. Their dams help reduce soil [[erosion]] and can help reduce flooding. During the summer, beavers eat grasses, [[cattail]]s, [[Nymphaeaceae|water lilies]] and  other aquatic plants.
-Beavers usually mate for life. The young beaver "kits" typically remain with their parents for up to two years. The American Beaver is distinguished from its cousin, the [[European Beaver]], by its stronger teeth and greater reproductive capacity.<ref>[http://www.helsinki.fi/lehdet/uh/201a.htm Universitas Helsingiensis 2/01<!-- Bot generated title -->]</ref>
-An emerging problem is the descendants of an introduced population in Tierra del Fuego, Argentina. The escapees from a farmed population of 25 animals has bloomed to an estimated 100,000; the drastically different ecosystem has led to incredible environmental damage, as the ponds created by the beavers have no ecological purpose (wetlands do not form there as they do in the beavers' native territory) and there are no native, large predators. They have also been found to cross saltwater to islands northward; a possible encroachment on the mainland has naturalists highly concerned.
-Beaver meat is similar tasting to lean beef, but care must be taken to prevent contamination from the animal's strong castor (musk) gland. It is usally slow-cooked in a broth, and was a valuable food source to Native Americans.{{Fact|date=January 2008}} In parts of North America, fried pastries called [[Fried dough#BeaverTails|beaver tails]] may be found. Despite their name, they contain no beaver.
-== Subspecies ==
-There are 25 subspecies of the American Beaver, but different subspecies have been reintroduced to areas with previously geographically isolated subspecies, following population decline or extirpation of the indigenous subspecies. This has led to very substantial mixing of the subspecies gene pools, and some subspecies may have disappeared entirely.
-The most widespread subspecies in North America are ''C. c. acadicus'', ''C. c. canadensis'' (Canadian beaver), ''C. c. carolinensis'' (Carolina beaver), and ''C. c. missouriensis'' (Missouri River beaver).<ref name="baker">Baker, B. W., and E. P. Hill. [http://www.fort.usgs.gov/products/publications/909/909.pdf Beaver (Castor canadensis)]. G. A. Feldhamer, B. C. Thompson, and J. A. Chapman, editors. Wild Mammals of North America: Biology, Management, and Conservation. Second Edition. The Johns Hopkins University Press, Baltimore, Maryland, USA, pp. 288-310. 2003. Retrieved on [[2007]]-[[08-04]].</ref> The Canadian beaver originally inhabited almost all of the forested area of Canada,<ref>Kieffer, Michael [http://www.fobr.org/article-meadows_mist.html Meadows in Mist] Bull Run Mountains Conservancy, Inc. Retrieved on [[2007]]-[[08-04]].</ref> and because of its more valued fur, was often selected for reintroductions elsewhere. The Carolina beaver is found in the southeastern United States, the Missouri River beaver, as its name suggests, is found in the [[Missouri River]] and its tributaries, and ''C. c. acadicus'' is found throughout the [[New England]] area in the northeastern United States.
-== Threats ==
-These animals are considered [[pest (animal)|pest]]s in some parts of their range because their dams can cause flooding in nearby areas. They are persistent in repairing any damage to the dam and the only effective measure is to remove them.  In [[1999]] Washington, DC's annual [[Cherry Blossom Festival]] was plagued by a family of beavers who lived in the [[Tidal Basin]].  The offenders were caught and removed, but not before damaging 14 cherry trees, including some of the largest and oldest trees.[http://www.cnn.com/US/9904/11/chomping.cherry.tree/] [http://www.washingtonpost.com/wp-srv/local/daily/april99/chomp7.htm]
-Non-lethal methods of containing beaver-related flooding have been developed.  One such device has been utilized by both the Canadian and U.S. governments, called "Beaver Deceivers," or levelers, invented and pioneered by wildlife biologist, Skip Lisle.
-These animals are often trapped for their fur. During the early [[19th century]], trapping eliminated this animal from most of its original range. The beaver furs were used to make clothing and [[top-hat]]s. Much of the early exploration of North America was driven by the quest for this animal's fur. Native peoples and early settlers also ate this animal's meat. The current beaver population has been estimated to be 10 to 15 million; there may have originally been ten times that many beavers in North America before the days of the [[fur trade]].
-Common natural predators include [[Gray Wolf|Gray Wolves]], [[Coyote]]s, and [[Cougar|mountain lions]]. Less significant predators include [[bear]]s, which can dig into a lodge, [[wolverine]]s, [[Northern river otter|river otters]], [[Canadian lynx]], [[bobcat]]s, and [[mink]].<ref name="baker" />
-[[Image:beaver_damage_navarino_chile.JPG|thumb|right|Beaver damage on the north shore of Robalo Lake, [[Navarino Island]], [[Chile]].]]
-In the 1940s, beavers were brought to the island of [[Tierra Del Fuego]] in southern [[Argentina]], for commercial fur production. However, the project failed and the beavers were released into the wild. Having no natural predators in their new environment, they quickly spread throughout the island, reaching a number of 100,000 individuals within just 50 years (when released into the wild there were only a few pairs). They are now considered a serious [[invasive species]] on the island, due to their massive destruction of forest trees, and efforts are being made for their eradication<ref>[http://edition.cnn.com/NATURE/9907/09/argentina.beaver/ CNN - Argentina eager to rid island of beavers - July 9, 1999<!-- Bot generated title -->]</ref>.
-== The beaver as symbol ==
-[[Image:Cdn-nickel-reverse.jpg|100px|left|Beaver on the Canadian nickel (five-cent piece).]]
-One of the national symbols of Canada, the beaver is depicted on the [[Nickel (Canadian coin)|Canadian five-cent piece]] and was on the first Canadian postage stamp, the Three Penny Beaver. It is also the state animal of [[Oregon]] and [[New York State|New York]], and a common school emblem for [[engineering]] schools, including the [[California Institute of Technology]] and the [[Massachusetts Institute of Technology]], as well as the mascot for [[Oregon State University]]. The beaver also appears in the [[coat of arms|coats of arms]] of the [[University of Toronto]] and the [[London School of Economics]].
-== Gallery ==
-<gallery>
-Image:AmericanBeaver pennsylvania.jpg
-Image:AmericanBeaver pennsylvania2.jpg
-Image:AmericanBeaver pennsylvania3.jpg
-Image:American Beavers at the National Zoo.jpg
-Image:TZ Beaver.jpg
-Image:North_American_Beaver_2_Indiana.jpg
-Image:North_American_Beaver_4_Indiana.jpg
-Image:North_American_Beaver_5_Indiana.jpg
-</gallery>
-==References==
-{{reflist}}
-==Further reading==
-* {{ITIS|ID=180212|taxon=Castor canadensis|year=2006|date=18 March}}
-* {{cite book|last=Long|first=Kim|title=Beavers: A Wildlife Handbook|publisher=Johnson Books|location=Boulder|pages=37|year=2000|isbn=1-55566-251-X}}
-* {{IUCN2006|assessors=MacDonald & Cook|year=2000|id=4003|title=Castor canadensis|downloaded=12 May 2006}}
-==External links==
-{{commons|Castor canadensis}}
-{{wikispecies|Castor canadensis}}
-* [http://www.ecology.info/beaver-ecology.htm Ecology of the Beaver]
-* [http://www.pch.gc.ca/progs/cpsc-ccsp/sc-cs/o1_e.cfm Canadian Heritage - the beaver as a national symbol]
-* [http://purl.galileo.usg.edu/ugafax/QL737xR6xD84 The romance of the beaver;] being the history of the beaver in the western hemisphere, by A. Radclyffe Dugmore. Illustrated with photographs from life and drawings by the author. Publisher: Philadelphia, J.B. Lippincott company; London, W. Heinemann [[1914]] ''(a searchable facsimile at the University of Georgia Libraries)''
-*Gallant, D., C.H. Bérubé, E. Tremblay, & L. Vasseur (2004). An extensive study of the foraging ecology of beavers (''Castor canadensis'') in relation to habitat quality. [http://www.colby.edu/academics_cs/courses/BI312/upload/ForagingBeaversHabitatQuality.pdf Canadian Journal of Zoology] 82:922–933.
-[[Category:Beavers]]
-[[Category:Fur trade]]
-[[Category:Mammals of Canada]]
-[[Category:Mammals of the United States]]
-[[Category:Fauna of Mexico]]
-[[Category:National symbols of Canada]]
-[[Category:Symbols of Oregon]]
-[[Category:Invasive animal species]]
-{{Link FA|he}}
-[[cs:Bobr kanadský]]
-[[de:Kanadischer Biber]]
-[[et:Kanada kobras]]
-[[es:Castor canadensis]]
-[[eo:Kanada kastoro]]
-[[fr:Castor canadien]]
-[[he:בונה קנדי]]
-[[lv:Kanādas bebrs]]
-[[lt:Kanadinis bebras]]
-[[hu:Kanadai hód]]
-[[nl:Canadese bever]]
-[[pl:Bóbr kanadyjski]]
-[[ru:Канадский бобр]]
-[[fi:Kanadanmajava]]
-[[sv:Amerikansk bäver]]