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{{Taxobox
| name = American Alligator
| status = LR/LC
| status_system = IUCN2.3
| status_ref = <ref>{{IUCN2008 | assessors=Crocodile Specialist Group | year=1996 | title=Alligator mississippiensis | id=46583 | downloaded=24 February 2009}}</ref>
| image = American Alligator.jpg
| image_caption = An American Alligator in captivity at the Columbus Zoo, in Powell, Ohio
| image_width = 230px
| regnum = [[Animal]]ia
| phylum = [[Chordate|Chordata]]
| classis = [[Reptilia]]
| unranked_ordo = [[Archosauria]]
| ordo = [[Crocodilia]]
| familia = [[Alligatoridae]]
| genus = ''[[Alligator]]''
| species = '''''A. mississippiensis'''''
| binomial = ''Alligator mississippiensis''
| binomial_authority = ([[François Marie Daudin|Daudin]], 1802)
| synonyms = ''Crocodilus mississipiensis'' [sic] [[François Marie Daudin|Daudin]], 1802<br>''Alligator mississippiensis'' [[John Edwards Holbrook|Holbrook]], 1842
| range_map = Rangemapx.gif
| range_map_width = 210px
| range_map_caption = American Alligator range map
}}

The '''American alligator''' (''Alligator mississippiensis''), sometimes referred to colloquially as a ''' gator''', is a [[reptile]] endemic only to the [[American South|Southeastern United States]]. It is one of the two living [[species]] of [[alligator]], in the [[genus]] ''[[Alligator]]'', within the family ''[[Alligatoridae]]''. It is larger than the other extant alligator species, the [[Chinese alligator]].

The American alligator inhabits wetlands that frequently overlap with human-populated areas.

== Description ==
{| style="float:left; float:right;"
|-
| [[File:Alligator Left Forepaw.jpg|120px|thumb|left|Forelimb showing the large claws and slight webbing between the toes]] || [[File:Alligator Tail.jpg|thumb|left|75px|Tail which is for aquatic propulsion and as a weapon of defense]]
|}
the ansestor of the'''American alligator''' were named latyra, and pactrick.

The American alligator has a large, slightly rounded body, with thick limbs, a broad head, and a very powerful tail. Adult Alligators generally have dark gray or nearly black color. They may at times appear to be lighter based on detritus or algae in the water covering their skin. Juvenile alligators have a striped pattern for camouflage that they lose as they mature. Averaging about 9.5 in (24&nbsp;cm) in length when newly hatched, alligators reach sexual maturity when they measure about {{convert|5|–|7|ft|m|abbr=on}}.<ref>[http://www.robinsonlibrary.com/science/zoology/reptiles/crocodilia/alligator.htm|Alligator Profile] (2011).</ref> Adult male alligators average {{Convert|11.2|ft|m|abbr=on}} in length, while adult females average {{Convert|8.2|to|9.8|ft|m|abbr=on}}.<ref name = "ufl">{{cite web|url=http://www.flmnh.ufl.edu/cnhc/csp_amis.htm |title=Crocodilian Species—American Alligator (Alligator mississippiensis) |publisher=Flmnh.ufl.edu |date= |accessdate=2008-10-14}}</ref><ref name="woodward-et-al">{{cite journal
|doi=10.2307/1564733
|title=Maximum Size of the Alligator (''Alligator mississippiensis'')
|jstor=1564733
|author=Woodward, Allan R.; White, John H.; Linda, Stephen B.
|journal=[[The Society for the Study of Amphibians and Reptiles|Journal of Herpetology]]|volume=29|issue=4|year=1995
|pages=507–513}}</ref><ref>http://nationalzoo.si.edu/Anis highmals/ReptilesAmphibians/Facts/FactSheets/Americanalligator.cfm</ref><ref>[http://en.wikipedia.org/w/index.php?title=American_alligator&action=edit&section=1] (2011).</ref> Average body weights are reported from {{Convert|270|to|800|lb|kg|abbr=on}}, with a few exceptionally large and old males exceeding {{Convert|14|ft|m|abbr=on}} and {{convert|1000|lb|kg}}.<ref>http://www.thebigzoo.com/Animals/American_Alligator.asp</ref><ref>http://www.jacksonzoo.org/animals/documents/RAmericanAlligator.doc</ref><ref>http://animals.nationalgeographic.com/animals/reptiles/american-alligator/</ref> One American Alligator reached a length of {{convert|19|ft|2|in|m}} and 2,200&nbsp;lb (1,000&nbsp;kg),<ref>{{cite web|url=http://www.saltgrassflats.com/wildlife/alligator.html |title=Salt Grass Flats—American Alligator |publisher=Saltgrassflats.com |date= |accessdate=2008-12-02}}</ref> which made it not only the largest alligator ever recorded, but also among the largest crocodilians on record (although the related [[Black Caiman]] and 5 other crocodilians are believed to equal or exceed this size and prehistoric crocodilians such as ''[[Sarcosuchus]]'', ''[[Deinosuchus]]'', and ''[[Purussaurus]]'' reached much greater size). The tail, which accounts for half of the alligator's total length, is primarily used for aquatic propulsion. The tail can also be used as a weapon of defense when an alligator feels threatened. Alligators travel very quickly in water and while they are generally slow-moving on land, alligators can lunge short distances very quickly. They have five claws on each front foot and four on each rear foot. American Alligators have the strongest laboratory measured bite of any living animal, measured at up to {{convert|9452|N|lbf|lk=on}} in laboratory conditions. It should be noted that this experiment has not (at the time of the paper published) been replicated in any other crocodilians.<ref name="lappin">{{cite journal
|title=The ontogeny of bite-force performance in American alligator (Alligator mississippiensis)
|journal=[[Journal of Zoology]]
|volume=260|issue=3|pages=317–327
|url=http://www.alligatorfarm.us/images/Research/Erickson%20et%20al.%202003.pdf|format=PDF
|doi=10.1017/S0952836903003819
|year=2003
|last1=Erickson
|first1=Gregory M.
|last2=Lappin
|first2=A. Kristopher
|last3=Vliet
|first3=Kent A.
}}</ref>

Some alligators are missing an inhibited [[gene]] for [[melanin]], which makes them [[albinism|albino]]. These alligators are extremely rare and almost impossible to find in the wild. They could survive only in captivity. Like all albino animals, they are very vulnerable to the sun and predators.<ref>{{cite web|url=http://news.softpedia.com/news/White-albino-alligators-54575.shtml|title=White albino alligators |publisher=.softpedia.com |date= |accessdate=2008-10-27}}</ref>
American Alligators can remain underwater for several hours if not actively swimming or hunting (then it is only about 20 minutes); they do this by rerouting blood to reduce circulation to the lungs, and thus the need for oxygen.

==Habitat==
American alligators are mostly found in the [[Southeastern United States]], from [[Great Dismal Swamp]] in North Carolina south to [[Everglades National Park]] in [[Florida]] and west to the southern tip of [[Texas]]. They are found in the [[U.S. state]]s of [[North Carolina]], [[South Carolina]], [[Georgia (U.S. state)|Georgia]], [[Florida]], [[Louisiana]], [[Alabama]], [[Mississippi]], [[Arkansas]], [[Texas]], and [[Oklahoma]]. [[Florida]] and [[Louisiana]] currently have the largest population of alligators. [[Florida]] has an estimated population of 1 to {{Nowrap|1.5 million}} while [[Louisiana]] has an estimated population of 1.5 million

Although primarily [[freshwater]] animals, alligators will occasionally venture into [[brackish water]].<ref>{{cite web|url=http://www.uga.edu/srelherp/alligators/allmis.htm |title=American Alligator |publisher=Uga.edu |date= |accessdate=2008-12-02}}</ref>
Alligators live in [[wetland]]s and this is the vital habitat that holds the key to their continued long-term survival. Alligators depend on the wetlands, and in some ways the wetlands depend on them. As [[apex predator]]s, they help control the population of rodents and other animals that might overtax the [[marsh]]land vegetation.

American alligators are less prone to cold than [[American crocodile]]s. Unlike the American crocodile, which would immediately succumb to the cold and drown in water of 45&nbsp;°F (7.2&nbsp;°C), an alligator can survive in such temperatures for some time without any signs of evident discomfort.<ref name="Guggisberg">{{cite book | author = Guggisberg, C.A.W. |url = | title = Crocodiles: Their Natural History, Folklore, and Conservation| year = 1972 | page = 195 | isbn = 0-7153-5272-5 | publisher = David & Charles | location = Newton Abbot}}</ref> It is thought that this adaptiveness is the reason why American alligators spread farther north than the American crocodile.<ref name="Guggisberg"/> In fact, the American alligator is found farther from the equator and is more equipped to deal with cooler conditions than any other crocodilian.<ref>{{cite journal |title=Alligator physiology and life history: the importance of temperature |first=Valentine A. |last=Lance |journal=Experimental Gerontology |volume=38 |issue=7 |year=2003 |pages=801–805 |doi=10.1016/S0531-5565(03)00112-8 }}</ref>

In [[Florida]], alligators face ambient temperature patterns unlike elsewhere in their range. The consistently high temperatures lead to increased [[metabolism|metabolic]] cost. Alligators in the [[Everglades]] have reduced length to weight ratio, reduced total length, and delayed onset of sexual maturity compared with other parts of their range. The reason for this poor condition is currently suspected to be a combination of low food availability and sustained high temperatures.

==Diet==
[[File:Gator-with-deer2.jpg|thumb|right|Alligators are [[apex predator]]s capable of killing large terrestrial prey. This large American alligator has caught an adult deer.]]

Alligators eat [[fish]], [[bird]]s, [[turtle]]s, [[snake]]s, [[mammal]]s, and [[amphibian]]s. Hatchlings diet on invertebrates, insects, [[larva]]e, [[snail]]s, [[spider]]s, [[worm]]s, and other small prey. They will also eat small [[fish]] at any opportunity. As they grow, they gradually move on to larger [[fish]], [[mollusca|mollusk]]s, [[frog]]s and small mammals like [[rat]]s, and [[mouse|mice]]. Some adult alligators take a larger variety of prey ranging from a [[snake]] or [[turtle]] to a [[bird]] and moderate sized [[mammal]]s like a [[raccoon]] or [[deer]].

Once an alligator reaches adulthood, any animal living in the water or coming to the water to drink is potential prey. Adult alligators will eat [[wild boar]]s, [[deer]], [[dog]]s of all sizes, livestock including [[cattle]] and [[sheep]], and are often known to kill and eat smaller alligators. In rare instances, large male alligators have been known to prey on the [[Florida panther]] and [[American black bear]], making the American alligator the [[apex predator]] throughout its distribution.<ref>{{cite web |url=http://www.sciencedaily.com/articles/a/american_alligator.htm |title=American Alligator |publisher=Sciencedaily.com |date= |accessdate=2008-10-14}}</ref> The American alligator is known as King of the Everglades, although the [[American crocodile]], which shares parts of the Everglades with the alligator, is capable of growing larger (over 5 meters), mostly in warmer regions like Central America, Mexico, and the Caribbean.

Although fish and other prey taken in the water or at the water edge form the major part of alligator's diet, adult alligators also spend considerable time hunting on land, up to 50 m (170&nbsp;feet) from water, ambushing terrestrial animals on trailsides and road shoulders on warm nights.<ref>{{cite journal | author=Dinets, V.L.
| year = 2011
| title = On terrestrial hunting in crocodilians | volume=114| journal = Herpetological Bulletin | pages = 15–18}}</ref>

The [[gizzard]]s (stomachs) of alligators often contain [[gastrolith]]s. The function of these stones is to grind up food in the stomach and help with digestion. This is important because gators swallow their food whole. These [[gastrolith]]s are also used in [[buoyancy]] control.

In 2005, the bite force of a {{convert|12|ft|m|adj=on}}, {{convert|450|lb|adj=on}} alligator was measured to be 2209 [[pounds-force]] (9.826 [[Kilonewton|kN]]). It was measured by Greg Ericson.<ref>BBC - The Truth about Killer Dinosaurs</ref>
American alligators cruise through water at just over {{convert|1|mph|m/s|1|abbr=on}}; in pursuit of prey they can swim much faster over short distances.

==Reproduction==
[[File:Alligator mississippiensis 2 babies.jpg|thumb|right|Young American Alligators basking]]

The [[Reproduction|breeding]] season begins in the spring. Although alligators have no [[vocal folds|vocal cords]], males bellow loudly to attract mates and warn off other males during this time by sucking air into their lungs and blowing it out in intermittent, deep-toned roars. Male alligators are also known to use [[infrasound]] during their mating behavior, as one of their routines is to engage in bellowing in infrasound while their head and tail are above the water, with their midsection very slightly submerged, making the surface of the water that is directly over their back literally "sprinkle" from their infrasound bellowing, in a so-called "water dance".<ref>{{cite journal | author=Garrick, L.D. and Lang, J.W.
| year = 1977
| title = Social Displays of the American Alligator | volume=17| journal = American Zoologist | pages = 225–239}}</ref> Recently it was discovered that on spring nights alligators gather in large numbers for group courtship, the so-called "alligator dances".<ref>{{cite journal | author=Dinets, V.L.
| year = 2010
| title = Nocturnal behavior of the American Alligator (''Alligator mississippiensis'') in the wild during the mating season | volume=111| journal = Herpetological Bulletin | pages = 4–11}}</ref>

[[File:Crocnest.JPG|thumb|left|Alligator nest and young in Florida]]

The female builds a nest of vegetation, sticks, leaves, and mud in a sheltered spot in or near the water. After she lays her 20 to 50 white, goose egg-sized eggs, she covers them under more vegetation, which, like mulch, heats as it decays, helping to keep the eggs warm. This differs from [[Nile crocodile]]s who lay their eggs in pits.<ref name="Guggisberg" />

The temperature at which alligator eggs develop determines their sex. Those eggs which are hatched in temperatures ranging from 90 to 93 degrees Fahrenheit (32 to 34&nbsp;°C) become males, while those in temperatures from 82 to 86&nbsp;°F (23 to 30&nbsp;°C) become female. Intermediate temperature ranges have proven to yield a mix of both male and females. The female will remain near the nest throughout the 65-day [[avian incubation|incubation]] period, protecting the nest from intruders. When the young begin to hatch they emit a high-pitched croaking noise, and the mother quickly digs them out.

[[File:Alligator mississippiensis baby.jpg|thumb|Juvenile American alligator swimming, showing the distinctive yellow striping found on juveniles]]

The young are tiny replicas of adult alligators with a series of yellow bands around their bodies. They find their way to water after hatching. For several days they continue to live on yolk masses within their stomachs. The baby spends about five months with the mother before leaving her. [[Snapping turtles]], large [[snakes]], [[raccoons]], [[largemouth bass]], [[American black bears]] and large raptorial birds like [[great horned owl]]s and [[bald eagle]]s prey upon the young. The adult alligator grows up to prey upon many of the same species.

Alligators reach breeding maturity at about 6 to 10 years of age, at which time they are about 6 to 7 feet (1.8–2.1&nbsp;m) long. From then on, growth continues at a slower rate. The oldest males may grow to be 16 feet (4.85&nbsp;m)<ref>{{cite web|url=http://animal.discovery.com/fansites/crochunter/australiazoo/06amerigator.html |title=Animal Planet :: Australia Zoo—American Alligator |publisher=Animal.discovery.com |date=October 13, 2008 |accessdate=2008-10-14}}</ref> long and weigh up to 1,200 [[pound (mass)|pounds]] (510&nbsp;kg) during a lifespan of 30 or more years. A recent study by scientists from the [[Savannah River Ecology Laboratory]] in South Carolina reveals that up to 70 percent of ''A. mississippiensis'' females chose to remain with their partner, often for many years.<ref>{{cite web |url=http://www.macroevolution.net/alligator-mating.html |title=Alligator Mating (www.macroevolution.net) |accessdate=2009-10-28}}</ref>

== Relationships with humans ==
=== Human deaths and injuries ===
{{main|List of fatal alligator attacks in the United States by decade}}
Alligators are capable of killing humans, but are generally wary enough not to see them as a potential prey. Alligator bites are serious injuries due to the reptile's sheer bite force and risk of infection. Even with medical treatment, an alligator bite may still result in a fatal infection.<ref>{{cite journal |last=Harding |first=Brett E. |last2=Wolf |first2=Barbara C. |title=Alligator Attacks in Southwest Florida |journal=Journal of Forensic Sciences |volume=51 |issue=3 |pages=674–677 |year=2006 |doi=10.1111/j.1556-4029.2006.00135.x }}</ref> The alligator's tail is a formidable weapon that can easily knock a person down and break their bones. Alligators are protective parents who will protect their young by attacking anything that comes too close or poses threats to baby alligators.

Since 1948, there have been more than 275 unprovoked attacks on humans in Florida, of which at least 17 resulted in death.<ref>Living with Alligators, Myfwc.com [http://web.archive.org/web/20071016203825/http://myfwc.com/gators/faq/lwa.htm] on the [[Internet Archive]]</ref> There were only nine fatal attacks in the U.S. throughout the 70s, 80s, and 90s, but alligators killed 12 people from 2001 to 2007. In May 2006, alligators killed three Floridians in less than a week.<ref>{{cite news|url=http://www.nytimes.com/2006/05/15/us/15alligator.html |title=A String of Deaths by Gators in Florida |publisher=nytimes.com |date= 2006-05-15|accessdate=2006-05-15}}</ref>

=== Alligator wrestling ===

{{main|Alligator wrestling}}

Several Florida tourist attractions have taken advantage of fears and myths about alligators—as well as the reality of their danger—through a practice known as alligator wrestling. Created in the early 20th century by some members of the [[Miccosukee]] and [[Seminole]] Tribe of Florida, this tourism tradition continues to the present day.

=== Endangered species recovery ===
[[File:Albino Alligator 2008.jpg|[[Albinism|Albino]] American alligator|250px|thumb|thumb|

An albino alligator could survive only in captivity.]]
Historically, alligators were depleted from many parts of their range as a result of market hunting and loss of habitat, and 30 years ago many people believed their population would never recover. In 1967, the alligator was listed as an endangered species (under a law that preceded the [[Endangered Species Act]] of 1973), meaning it was considered in danger of [[extinction]] throughout all or a significant portion of its range.

A combined effort by the [[United States Fish and Wildlife Service]], state wildlife agencies in the [[Southern United States|South]], and the creation of large, commercial alligator farms were instrumental in aiding the American alligator's recovery. The Endangered Species Act outlawed alligator [[hunting]], allowing the species to rebound in numbers in many areas where it had been depleted. As the alligator began to make a comeback, states established alligator population monitoring programs and used this information to ensure alligator numbers continued to increase. In 1987, the Fish and Wildlife Service pronounced the American alligator fully recovered and consequently removed the animal from the list of endangered species. The Fish and Wildlife Service still regulates the legal trade in alligator skins and products made from them.

Recently, a population of non-native [[Burmese Python]]s has become established in Everglades National Park. While there have been observed events of predation by Burmese pythons on alligators and vice versa, there is currently no evidence of a net negative effect on alligator populations.<ref>[http://www.msnbc.msn.com/id/9600151/ Gator-guzzling python comes to messy end]. Published 2005-10-05 by [[Associated Press]]. Retrieved 2008-03-11.</ref><ref>Butler, Rhett A. (2005-10-05 [http://news.mongabay.com/2005/1005-gator.html Python explodes after swallowing 6-foot alligator in Florida Everglades]. Mongabay.com. Retrieved 2008-03-11.</ref><ref name="USGS">[[United States Department of the Interior]], [[U.S. Geological Survey]] (2008-02-20). [http://www.usgs.gov/newsroom/article.asp?ID=1875 USGS Maps Show Potential Non-Native Python Habitat Along Three U.S. Coasts]. www.usgs.gov. Retrieved 2008-03-11.</ref>

=== Alligator farming ===
{{main|Alligator farm}}
Alligator farming is a big and growing industry in Georgia, Florida, Texas and Louisiana. These states produce a combined annual total of some 45,000 alligator hides. Alligator hides bring good prices and hides in the {{Convert|6|to|7|ft|m}} range have sold for $300 each, though the price can fluctuate considerably from year to year. The market for alligator meat is growing and approximately {{Convert|300000|lb|kg}} of meat is produced annually. According to the [[Florida Department of Agriculture and Consumer Services]], raw alligator meat contains roughly 200 calories (840 kJ) per {{Convert|3|oz|g}} serving size, of which 27 calories (130 kJ) come from fat.<ref>{{cite web|url=http://www.annecollins.com/calories/calories-alligator.htm |title=Calories in Alligator, Crocodile |publisher=Annecollins.com |date= |accessdate=2008-12-11}}</ref>

Alligator meat is sometimes used in [[jambalaya]]s, [[soup]]s, and [[stew]].

===Symbol===

[[File:Albert and Alberta.jpg|thumb|upright|right|alt=Two alligator mascots with their arms wrapped around each other posing for a photo.|[[Albert and Alberta Gator]], the mascots of the [[University of Florida]]; the school chose the alligator as mascot 75 years before the state of Florida named it as official state reptile.]]

The American alligator is the official [[state reptile]] of three states: Florida, Louisiana, and Mississippi. In addition, the [[Florida Gators|Gators]] have titled the [[University of Florida]]'s teams since 1911. In that year, a printer made a spur-of-the-moment decision to print an alligator emblem on a shipment of the schools football pennants; the mascot stuck, perhaps because the team captain's nickname was Gator.<ref>{{cite web | url = http://www.ufl.edu/history/1906.html | title = History: 1906–1927, early Gainesville | accessdate = February 13, 2011 | publisher = University of Florida}}</ref>
{{-}}

==See also==
*[[Alligatoridae]]
*[[Alligator (film)|''Alligator'' (film)]], a movie about a giant alligator living in the sewer of an Illinois town
*[[Wally Gator]], a cartoon about an anthropomorphic alligator
*[[Everglades]]
*[[The Alligator People]]
*[[Gatorland]]
*[[Brazos Bend State Park]]

==Notes==
{{reflist|colwidth=30em}}

==External links==
{{commons|Alligator mississippiensis}}
*[http://www.crocodilian.com Crocodilian Online]
*[http://www.floridamemory.com/PhotographicCollection/photo_exhibits/alligators/index.cfm Photo exhibit on alligators in Florida; from State Archives of Florida]
*[http://www.fws.gov/video/sound.htm U.S. Fishery and Wildlife Service – alligator bellows and hisses]
* [http://www.care-sheet.com/index/Alligator_mississippiensis American Alligator] at care-sheet.com (Wiki''Pets'')

{{Crocodilia|A.}}
{{Crocs}}
{{North American Game}}

{{DEFAULTSORT:Alligator, American}}
[[Category:Crocodilians]]
[[Category:Symbols of Florida]]
[[Category:Megafauna of North America]]
[[Category:Endemic fauna of the United States]]
[[Category:Reptiles of the United States]]
[[Category:Alligatoridae]]
[[Category:Cuisine of the Southern United States]]
[[Category:Florida culture]]
[[Category:Fauna of the Southeastern United States]]
[[Category:Louisiana culture]]
[[Category:Mississippi culture]]
[[Category:Animals described in 1802]]

[[ar:قاطور أمريكي]]
[[zh-min-nan:Bí-kok Té-bún-kho̍k]]
[[br:Aligator Amerika]]
[[bg:Американски алигатор]]
[[cs:Aligátor severoamerický]]
[[de:Mississippi-Alligator]]
[[nv:Bitseeʼ yee adiłhałii]]
[[es:Alligator mississippiensis]]
[[fr:Alligator d'Amérique]]
[[hr:Američki aligator]]
[[it:Alligator mississippiensis]]
[[he:אליגטור אמריקני]]
[[ka:ამერიკული ალიგატორი]]
[[la:Alligator mississippiensis]]
[[lt:Misisipės aligatorius]]
[[hu:Mississippi aligátor]]
[[mk:Американски алигатор]]
[[nl:Amerikaanse alligator]]
[[ja:アメリカアリゲーター]]
[[no:Amerikansk alligator]]
[[pl:Aligator amerykański]]
[[pt:Jacaré-americano]]
[[ru:Американский аллигатор]]
[[sk:Aligátor severoamerický]]
[[fi:Mississippinalligaattori]]
[[sv:Mississippialligator]]
[[th:แอลลิเกเตอร์อเมริกา]]
[[tr:Amerika aligatoru]]
[[uk:Американський алігатор]]
[[zh-yue:美國短吻鱷]]
[[zh:美國短吻鱷]]

Revision as of 14:30, 8 November 2011

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