View source for American alligator

{{Short description|Crocodilian native to the Southeastern United States}}
{{Distinguish|text=the [[American crocodile]]}}
{{Good article}}
{{Use mdy dates|date=September 2016}}
{{speciesbox
| name = American alligator
| fossil_range = {{fossil range|Middle Pleistocene|Present}}
| image = American Alligator.jpg
| image_caption = At the [[Columbus Zoo and Aquarium]] in [[Powell, Ohio]]
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name=iucn>{{cite iucn|author1=Elsey, R.|author2= Woodward, A. |author3 = Balaguera-Reina, S.A. |name-list-style=amp |title=''Alligator mississippiensis'' |article-number=e.T46583A3009637|year=2019|doi=10.2305/IUCN.UK.2019-2.RLTS.T46583A3009637.en}}</ref>
| status2 = CITES_A2
| status2_system = CITES
| status2_ref = <ref name = "CITES">{{cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php|access-date=2022-01-14|website=cites.org}}</ref>
| display_parents = 2
| genus = Alligator
| species = mississippiensis
| authority = ([[François Marie Daudin|Daudin]], 1802)
| synonyms = *''Crocodilus mississipiensis'' {{sic}}<br />{{small|Daudin, 1802}}
* ''Crocodilus lucius'' <br />{{small|[[Georges Cuvier|Cuvier]], 1807}}
* ''Crocodilus cuvieri'' <br />{{small|[[William Elford Leach|Leach]], 1815}}
* ''Alligator lucius'' <br />{{small|— [[André Marie Constant Duméril|A.M.C. Duméril]] & [[Gabriel Bibron|Bibron]], 1836}}
* ''Alligator mississippiensis'' {{sic}}<br />{{small|— [[John Edwards Holbrook|Holbrook]], 1842}}
| synonyms_ref = <ref>{{EMBL species|genus=Alligator|species=mississippiensis}}. www.reptile-database.com.</ref>
| range_map = The_range_of_the_American_Alligator.png
| range_map_caption = Approximate range of American alligator
}}

The '''American alligator''' ('''''Alligator''' '''mississippiensis'''''), sometimes referred to as a '''common alligator''' or just '''gator''', is a large [[crocodilia]]n [[reptile]] native to the [[Southeastern United States]]. It is one of the two [[extant species]] in the [[genus]] ''[[Alligator]]'', and is larger than the only other living alligator species, the [[Chinese alligator]].

Adult male American alligators measure {{convert|3.4|to|4.5|m|ft|1|abbr=on}} in length, and can weigh up to {{convert|500|kg|lb|-2|abbr=on}}, with unverified sizes of up to {{convert|5.84|m|ft|1|abbr=on}} and weights of {{convert|1000|kg|lb|abbr=on}} making it the second longest and the heaviest of the [[family (biology)|family]] [[Alligatoridae]], after the [[black caiman]]. Females are smaller, measuring {{convert|2.6|to|3|m|ft|abbr=on}} in length.<ref name="natgeo"/><ref name="philadelphiazoo.org"/><ref name="animalspot"/><ref name="gatorfact"/><ref name="nationalzoo"/> The American alligator inhabits [[humid subtropical climate|subtropical]] and [[tropical]] freshwater [[wetland]]s, such as [[marsh]]es and cypress [[swamp]]s, from southern Texas to [[North Carolina]].<ref>Virginia Living Museum. (2016, April 30). Herp highlight #1: American alligator. Retrieved April 08, 2021, from https://thevlm.org/herp-highlight-1-american-alligator/</ref> It is distinguished from the [[sympatric]] [[American crocodile]] by its broader snout, with overlapping jaws and darker coloration, and is less tolerant of saltwater but more tolerant of cooler climates than the American crocodile, which is found only in tropical and warm subtropical climates.

American alligators are [[apex predator]]s and consume fish, [[amphibian]]s, reptiles, birds, and [[mammal]]s. Hatchlings feed mostly on [[invertebrate]]s. They play an important role as [[ecosystem engineer]]s in [[wetland]] ecosystems through the creation of alligator holes, which provide both wet and dry habitats for other organisms. Throughout the year (in particular during the breeding season), American alligators bellow to declare territory, and locate suitable mates.<ref>{{cite journal |last=Vilet|first=Kent |title=Social Displays of the American Alligator (''Alligator mississippiensis'') |journal=American Zoology |year=1989 |volume=2 |issue=3|pages=1019–1031 |doi=10.1093/icb/29.3.1019|doi-access=free }}</ref> Male American alligators use [[infrasound]] to attract females. Eggs are laid in a nest of vegetation, sticks, leaves, and mud in a sheltered spot in or near the water. Young are born with yellow bands around their bodies and are protected by their mother for up to one year.<ref>{{cite web |last1=Pajerski |first1=Lauren |last2=Schechter |first2=Benjamin |last3=Street |first3=Robin |title=Alligator mississippiensis |year=2000 |url=http://animaldiversity.ummz.umich.edu/accounts/Alligator_mississippiensis/ |publisher=University of Michigan Museum of Zoology }}</ref> This species displays parental care, which is rare for most reptiles. Mothers protect their eggs during the incubation period, and move the hatchlings to the water using their mouths.<ref>Merchant, M., Savage, D., Cooper, A., Slaughter, M., Perkin, J. S., & Murray, C. M. (2018). Nest attendance patterns in the American alligator (Alligator mississippiensis). ''Copeia'', ''106''(3), 421-426.</ref>

The conservation status of the American alligator is listed as [[Least Concern]] by the [[International Union for Conservation of Nature]]. Historically, hunting had decimated their population, and the American alligator was listed as an [[endangered species]] by the [[Endangered Species Act of 1973]]. Subsequent conservation efforts have allowed their numbers to increase and the species was removed from endangered status in 1987. The species is the official [[state reptile]] of three states: [[Florida]], [[Louisiana]], and [[Mississippi]].

== History and taxonomy ==
The American alligator was first classified in 1801 by French zoologist [[François Marie Daudin]] as ''Crocodilus mississipiensis''. In 1807, [[Georges Cuvier]] created the [[genus]] ''[[Alligator]]'' for it,<ref>[https://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=174366 ''Alligator'' Cuvier, 1807]. ITIS.gov</ref> based on the English common name ''alligator'' (derived from Spanish word {{lang|es|el lagarto}}, "the lizard").

The American alligator and its closest living relative, the [[Chinese alligator]], belong the [[subfamily]] [[Alligatorinae]]. Alligatorinae is the [[sister taxon|sister group]] to the caimans of [[Caimaninae]], which together comprise the [[family (biology)|family]] [[Alligatoridae]] shown in this [[cladogram]]:<ref name="PanamaCrocs">{{Cite journal | last1 = Hastings | first1 = A. K. | last2 = Bloch | first2 = J. I. | last3 = Jaramillo | first3 = C. A. | last4 = Rincon | first4 = A. F. | last5 = MacFadden | first5 = B. J. | title = Systematics and biogeography of crocodylians from the Miocene of Panama | doi = 10.1080/02724634.2012.713814 | journal = Journal of Vertebrate Paleontology | volume = 33 | issue = 2 | page = 239 | year = 2013 | bibcode = 2013JVPal..33..239H | s2cid = 83972694 | doi-access = free }}</ref><ref name="NecrosuchusRev">{{Cite journal | last1 = Brochu | first1 = C. A. | doi = 10.1111/j.1096-3642.2011.00716.x | title = Phylogenetic relationships of Necrosuchus ionensis Simpson, 1937 and the early history of caimanines | journal = Zoological Journal of the Linnean Society | volume = 163 | pages = S228–S256 | year = 2011 | doi-access = free }}</ref>
{{clade| style=font-size:85%;line-height:85%
|label1='''[[Alligatoridae]]'''
|1={{clade
 |1='''[[Caimaninae]]'''
 |label2='''[[Alligatorinae]]'''
 |2={{clade
  |1=''[[Ceratosuchus burdoshi]]''{{extinct}}
  |2=''[[Hassiacosuchus haupti]]''{{extinct}}
  |3=''[[Navajosuchus mooki]]''{{extinct}}
  |4={{clade
   |1=''[[Wannaganosuchus brachymanus]]''{{extinct}}
   |2=''[[Arambourgia gaudryi]]''{{extinct}}
   |3={{clade
    |1=''[[Allognathosuchus polyodon]]''{{extinct}}
    |2=''[[Allognathosuchus wartheni]]''{{extinct}}
    |3=''[[Procaimanoidea kayi]]''{{extinct}} }}
   |label4=''[[Alligator]]''
   |4={{clade
    |1=''[[Alligator prenasalis]]''{{extinct}}
    |2={{clade
     |1=''[[Alligator mcgrewi]]''{{extinct}}
     |2={{clade
      |1=''[[Alligator olseni]]''{{extinct}}
      |2={{clade
       |1=''Alligator sinensis'' '''[[Chinese alligator]]'''
       |2={{clade
        |1=''[[Alligator thomsoni]]''{{extinct}}
        |2=''[[Alligator mefferdi]]''{{extinct}}
        |3=''Alligator mississippiensis'' '''American alligator''' }} }} }} }} }} }} }} }} }}

===Evolution===
[[File:AlligatorFL2007.JPG|thumb|In the [[Okefenokee Swamp]]]]
Fossils identical to the American alligator are found throughout the [[Pleistocene]], from 2.5 million to 11.7 thousand years ago.<ref>{{cite journal|doi=10.2307/3889340|title=Phylogenetics, Taxonomy, and Historical Biogeography of Alligatoroidea|last=Brochu|first=Christopher A.|journal=Society of Vertebrate Paleontology Memoir|volume=6|year=1999|pages=9–100|jstor=3889340}}</ref> In 2016, a Late [[Miocene]] fossil skull of an alligator, dating to approximately seven or eight million years ago, was discovered in [[Marion County, Florida]]. Unlike the other extinct alligator species of the same genus, the fossil skull was virtually indistinguishable from that of the modern American alligator. This alligator and the American alligator are considered to be [[sister taxa]], suggesting that the ''A.&nbsp;mississippiensis'' lineage has existed in North America for seven to eight million years.<ref name="Whiting2016">{{Cite journal |last1=Whiting |first1=Evan T. |last2=Steadman |first2=David W. |last3=Vliet |first3=Kent A. |date=June 1, 2016 |title=Cranial Polymorphism and Systematics of Miocene and Living Alligator in North America|journal=Journal of Herpetology |volume=50 |issue=2 |pages=306–315 |doi=10.1670/15-023 |s2cid=88200803 |issn=0022-1511}}</ref> However in 2020, a study reconsiders that American alligators Late Miocene record, with the older fossils being reassigned to ''[[Alligator mefferdi]]'' and ''[[Alligator hailensis]],'' and with American alligators evolving sometime during the [[Middle Pleistocene]].<ref name="S20">{{cite journal |last1=Stout |first1=J.B. |date=2020 |title=New early Pleistocene ''Alligator'' (Eusuchia: Crocodylia) from Florida bridges a Gap in ''Alligator'' evolution |url=https://www.researchgate.net/publication/344844631 |journal=Zootaxa |volume=4868 |issue=1 |pages=41–60 |doi=10.11646/zootaxa.4868.1.3 |pmid=33311408 |s2cid=226337860}}</ref>

The alligator's full [[mitochondrial genome]] was sequenced in the 1990s, and it suggests the animal evolved at a rate similar to mammals and greater than birds and most cold-blooded vertebrates.<ref>{{cite journal |author1=Janke, A. |author2=Arnason, U. |year=1997 |title=The complete mitochondrial genome of Alligator mississippiensis and the separation between recent archosauria (birds and crocodiles) |journal=Molecular Biology and Evolution |volume=14 |issue=12 |pages=1266–72 |pmid=9402737 |doi=10.1093/oxfordjournals.molbev.a025736 |doi-access=free}}</ref> However, the full [[genome]], published in 2014, suggests that the alligator evolved much more slowly than mammals and birds.<ref>{{cite journal |vauthors=Green RE, Braun EL, Armstrong J, Earl D, Nguyen N, Hickey G, Vandewege MW, St John JA, Capella-Gutiérrez S, Castoe TA, Kern C, Fujita MK, Opazo JC, Jurka J, Kojima KK, Caballero J, Hubley RM, Smit AF, Platt RN, Lavoie CA, Ramakodi MP, Finger JW, Suh A, Isberg SR, Miles L, Chong AY, Jaratlerdsiri W, Gongora J, Moran C, Iriarte A, McCormack J, Burgess SC, Edwards SV, Lyons E, Williams C, Breen M, Howard JT, Gresham CR, Peterson DG, Schmitz J, Pollock DD, Haussler D, Triplett EW, Zhang G, Irie N, Jarvis ED, Brochu CA, Schmidt CJ, McCarthy FM, Faircloth BC, Hoffmann FG, Glenn TC, Gabaldón T, Paten B, Ray DA |title=Three crocodilian genomes reveal ancestral patterns of evolution among archosaurs |journal=Science |volume=346 |issue=6215 |article-number=1254449 |year=2014 |pmid=25504731 |pmc=4386873 |doi=10.1126/science.1254449 |bibcode=2014Sci...34654449G }}</ref>

==Characteristics==
[[File:Alligator Crâne et Mandibule.jpg|thumb|American alligator skull]]
[[File:Alligator mississippiensis 3d scan Natural History Museum University of Pisa B 66.stl|thumb|3D scan of skeleton]]
Domestic American alligators range from long and slender to short and robust, possibly in response to variations in factors such as growth rate, diet, and climate.

===Size===
The American alligator is a relatively large species of crocodilian. On average, it is the largest species in the family [[Alligatoridae]], with only the [[black caiman]] being possibly larger.<ref>Thorbjarnarson, J. B. (2010). Black caiman ''Melanosuchus niger''. Crocodiles. Status Survey and Conservation Action Plan, 29–39.</ref> Weight varies considerably depending on length, age, health, season, and available food sources. Similar to many other reptiles that range expansively into temperate zones, American alligators from the northern end of their range, such as southern [[Arkansas]], [[Alabama]], and northern [[North Carolina]], tend to reach smaller sizes. Large adult American alligators tend to be relatively robust and bulky compared to other similar-length crocodilians; for example, captive males measuring {{convert|3|to|4|m|ftin|abbr=on}} were found to weigh {{convert|200|to|350|kg|lb|abbr=on}}, although captive specimens may outweigh wild specimens due to lack of hunting behavior and other stressors.<ref name= Woodward>{{cite journal|author=Woodward, A. R.|author2=White, J. H.|author3=Linda, S. B.|name-list-style=amp |year=1995|title=Maximum size of the alligator (''Alligator mississippiensis'')|journal= Journal of Herpetology|pages= 507–513|jstor=1564733|volume=29|issue=4|doi=10.2307/1564733 |bibcode=1995JHerp..29..507W }}</ref><ref>{{cite journal | last1 = Clippinger | first1 = T. L. | last2 = Avery Bennett | first2 = R. | last3 = Johnson | first3 = C. M. | last4 = Vliet | first4 = K. A. | last5 = Deem | first5 = S. L. | last6 = Orós | first6 = J. | last7 = Brown | first7 = M. B. | year = 2000 | title = Morbidity and mortality associated with a new mycoplasma species from captive American alligators (''Alligator mississippiensis'') | journal = Journal of Zoo and Wildlife Medicine | volume = 31 | issue = 3| pages = 303–314 | doi=10.1638/1042-7260(2000)031[0303:mamawa]2.0.co;2| pmid = 11237136 | s2cid = 42676388 }}</ref>

Large male American alligators reach an expected maximum size up to {{convert|4.6|m|ftin|abbr=on}} in length and weigh up to {{cvt|500|kg|lb|-2}}, while females reach an expected maximum of {{convert|3|m|ftin|abbr=on}}.<ref name="natgeo">[https://web.archive.org/web/20100117092307/http://animals.nationalgeographic.com/animals/reptiles/american-alligator American Alligators, American Alligator Pictures, American Alligator Facts – National Geographic]. Animals.nationalgeographic.com.</ref><ref name="philadelphiazoo.org">[http://www.philadelphiazoo.org/Animals/Reptiles/Crocodiles-Alligators/American-Alligator.htm American alligator] {{webarchive |url=https://web.archive.org/web/20130411194955/http://www.philadelphiazoo.org/Animals/Reptiles/Crocodiles-Alligators/American-Alligator.htm |date=April 11, 2013}}. Philadelphia Zoo.</ref><ref>{{cite book |title=Reptile biodiversity: standard methods for inventory and monitoring |date=2012 |publisher=University of California press |location=Berkeley (Calif.) |isbn=978-0-520-26671-1 |page=11 |url=https://books.google.com/books?id=H6m4YEF9MXwC}}</ref> However, the largest free-ranging female had a total length of {{Cvt|3.22|m|ftin}} and weighed {{Cvt|170|kg|lb}}.<ref>{{cite journal |last1=Deem |first1=Vincent R. |last2=Letter |first2=Andrew W. |last3=Woodward |first3=Allan R. |last4=Ford |first4=Ryan M. |last5=Moore |first5=Brandon C. |title=Maximum Size of Female American Alligators and a New Record Total Length and Weight |journal=Southeastern Naturalist |date=5 February 2021 |volume=20 |issue=1 |doi=10.1656/058.020.0109 |s2cid=232326848 |url=https://bioone.org/journals/southeastern-naturalist/volume-20/issue-1/058.020.0109/Maximum-Size-of-Female-American-Alligators-and-a-New-Record/10.1656/058.020.0109.short|url-access=subscription }}</ref> On rare occasions, a large, old male may grow to an even greater length.<ref name= Ross>Charles, S.; Ross, A. and Garnett, Stephen (1989) ''Crocodiles and Alligators''. Checkmark Books. {{ISBN|978-0-8160-2174-1}}.</ref><ref name = "Wood">{{cite book | author = Wood, Gerald | url = https://archive.org/details/guinnessbookofan00wood | title = The Guinness Book of Animal Facts and Feats | year = 1983 | publisher = Guinness Superlatives | isbn = 978-0-85112-235-9 }}</ref>

====Largest====
During the 19th and 20th centuries, larger males reaching {{convert|5|to|6|m|ftin|abbr=on}} were reported.<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 |access-date=October 14, 2008}}</ref> The largest reported individual size was a male killed in 1890 by Edward McIlhenny<ref>Woodward, A. R., White, J. H., & Linda, S. B. (1995). Maximum size of the alligator (Alligator mississippiensis). ''Journal of Herpetology'', 507-513.</ref> on [[Marsh Island (Louisiana)|Marsh Island]], [[Louisiana]], and reportedly measured at {{convert|5.84|m|ftin|abbr=on}} in length, but no voucher specimen was available, since the American alligator was left on a muddy bank after having been measured due to having been too massive to relocate.<ref name = "Wood"/> If the size of this animal was correct, it would have weighed about {{convert|1000|kg|lb|abbr=on}}.<ref>{{cite journal|author=Smith, E. N.|author2=Standora, E. A.|author3=Robertson, S. L.|name-list-style=amp |title=Physiological thermoregulation of mature alligators|journal=Comparative Biochemistry and Physiology. A, Comparative Physiology|volume=77|issue=1|pages=189–93|pmid=6141029|year=1984|doi=10.1016/0300-9629(84)90033-1}}</ref> In Arkansas, a man killed an American alligator that was {{convert|4.04|m|ftin|abbr=on}} and {{convert|626|kg|lb|abbr=on}}.<ref>{{cite web|url=https://www.foxnews.com/us/record-gator-caught-in-southwest-arkansas/|title=Record gator caught in Southwest Arkansas|publisher=FoxNews.com|access-date=March 15, 2014}}</ref> The largest American alligator ever killed in Florida was {{convert|5.31|m|ftin|abbr=on}}, as reported by the [[Everglades National Park]], although this record is unverified.<ref>[https://web.archive.org/web/20120205061623/http://www.everglades.national-park.com/bird.htm Everglades National Park Flora & Fauna Page]. Everglades National Park</ref><ref>[http://www.floridaadventuring.com/florida-alligator.html Florida alligator] {{Webarchive|url=https://web.archive.org/web/20131230232726/http://www.floridaadventuring.com/florida-alligator.html |date=December 30, 2013 }}. Floridaadventuring.com (March 2, 2016). Retrieved on 2016-09-07.</ref> The largest American alligator scientifically verified in Florida for the period from 1977 to 1993 was reportedly {{convert|4.23|m|ftin|abbr=on}} and weighed {{convert|473|kg|lb|abbr=on}}, although another specimen (size estimated from skull) may have measured {{convert|4.54|m|ftin|abbr=on}}.<ref name= Woodward/> A specimen that was {{convert|4.5|m|ftin|abbr=on}} long and weighed {{convert|458.8|kg|lb|1|abbr=on}} is the largest American alligator killed in Alabama and has been declared the SCI world record in 2014.<ref>{{cite journal |last1=Brunell |first1=Arnold M. |last2=Rainwater |first2=Thomas R. |last3=Sievering |first3=Michael |last4=Platt |first4=Steven G. |title=A New Record for the Maximum Length of the American Alligator |journal=Southeastern Naturalist |date=September 2015 |volume=14 |issue=3 |pages=N38–N43 |doi=10.1656/058.014.0302 |s2cid=86247523 |url=https://bioone.org/journals/southeastern-naturalist/volume-14/issue-3/058.014.0302/A-New-Record-for-the-Maximum-Length-of-the-American/10.1656/058.014.0302.short|url-access=subscription }}</ref><ref>{{cite journal |last1=Platt |first1=Steven G. |last2=Elsey |first2=Ruth M. |last3=Rainwater |first3=Thomas R. |last4=Fredenberg |first4=Mike |title=A Critical Analysis of a Historic Size Record for the American Alligator |journal=Southeastern Naturalist |date=1 November 2018 |volume=17 |issue=4 |doi=10.1656/058.017.0403 |s2cid=92148606 |url=https://bioone.org/journals/southeastern-naturalist/volume-17/issue-4/058.017.0403/A-Critical-Analysis-of-a-Historic-Size-Record-for-the/10.1656/058.017.0403.short|url-access=subscription }}</ref>

====Reported sizes====
{|class="wikitable sortable collapsible collapsed"
|-
!scope="col"| Date
!scope="col"| Location
!scope="col"| Reported length
!scope="col"| Reported weight
!scope="col"| Reported girth
!scope="col"| Reported skull length
!scope="col"| Scientifically analyzed length
!scope="col"| Comments

|-
| January 2, 1890
| Lake Vermilion, Louisiana
| 584.2&nbsp;cm
| not listed
| not listed
| not listed
| not listed
| Shot by [[Edward Avery McIlhenny]]. Body was too heavy to tow out of the mud.<ref>{{cite web|url=https://www.grunge.com/127199/19-foot-alligator-the-fascinating-true-story/|title=19-Foot Alligator: The Fascinating True Story|date=June 26, 2018}}</ref>

|-
| 1886
| Avery Island, Louisiana
| 523.24&nbsp;cm
| not listed
| not listed
| not listed
| not listed
| Captured alive by John Avery and died en route to the Smithsonian Institution after a sailor poured green paint on its back.<ref name="The Alligator's Life History">{{cite book | author=[[E.A. McIlhenny]]| title=The Alligator's Life History | publisher=Society for the Study of Amphibians and Reptiles| year=1976 | isbn=978-0-916984-00-7}}</ref>

|-
| March 1916
| Marsh Island, Louisiana
| 561.34&nbsp;cm
| not listed
| not listed
| not listed
| not listed
| Killed by Max Touchet, a game warden on Marsh Island following an attempted live capture.<ref name="Guinness Book of World Records Animal Facts and Feats">{{cite book | author=[[Gerald L Wood]]| title=Guinness Book of World Records Animal Facts and Feats | publisher=Sterling Pub Co., Inc| year=1982 | isbn=978-0-85112-235-9}}</ref>

|-
| 1956
| Lake Apopka, Florida
| 530.86&nbsp;cm
| not listed
| not listed
| not listed
| not listed
| Estimated by Allan Woodward to have been 421.64&nbsp;cm using head to length formula.<ref name="The Last of the Ruling Reptiles">{{cite book | author=[[Wilfred T. Neill]]| title=The Last of the Ruling Reptiles | publisher=Columbia University Press| year=1971 | isbn=978-0-231-03224-7}}</ref><ref>{{cite web|url=https://www.sun-sentinel.com/news/fl-xpm-1996-08-18-9608230262-story.html|title = Gator Tales| date=August 18, 1996 }}</ref>

|-
| November 11, 2010
| St Johns River, Florida
| 435.61&nbsp;cm
| 297&nbsp;kg
| not listed
| not listed
| 435.61&nbsp;cm
| <ref>{{Cite web|url=https://www.livescience.com/8921-alligator-hunter-nabs-florida-longest-gator.html|title=Alligator Hunter Nabs Florida's Longest Gator|author1=Live Science Staff|date=November 11, 2010|website=livescience.com}}</ref>

|-
| August 23, 2012
| Lake Talquin, Florida
| 426.72&nbsp;cm
| not listed
| not listed
| 60.325&nbsp;cm
| 426.72&nbsp;cm
|<ref>{{cite news| title=Huge alligator — with largest head ever found in Florida — caught and killed|newspaper=New York Daily News | date=23 August 2012 | url=https://www.nydailynews.com/2012/08/23/huge-alligator-with-largest-head-ever-found-in-florida-caught-and-killed/ | access-date=25 February 2024}}</ref>


|-
| August 16, 2014
| Alabama River, Alabama
| 480&nbsp;cm
| 458.8&nbsp;kg
| not listed
| not listed
| 480&nbsp;cm
| <ref>{{cite web|url=https://ourplnt.com/largest-alligator-ever-measured/#axzz6PMgZn9Tf|title= The Largest Alligator Ever Measured|date=August 2, 2015}}</ref>

|-
| May 31, 2016
| Palmetto, Florida
| 426.72&nbsp;cm
| not listed
| not listed
| not listed
| not listed
| Estimated to be between 426.72&nbsp;cm and 457.2&nbsp;cm when spotted.<ref>{{cite web|url=https://www.fox13news.com/news/watch-massive-gator-strolls-through-palmetto-golf-course|title=WATCH: Massive gator strolls through Palmetto golf course|date=May 31, 2016}}</ref><ref>{{cite web|url=https://www.foxnews.com/science/famous-15-foot-gator-named-chubbs-returns-to-florida-golf-course|title=Famous 15-foot gator named 'Chubbs' returns to Florida golf course|website=[[Fox News]]|date=October 16, 2018}}</ref><ref>{{Cite news|url=https://www.nytimes.com/2018/10/19/us/chubbs-alligator-florida.html|title = How is Chubbs the Alligator These Days? Glad You Asked|newspaper = The New York Times|date = October 19, 2018|last1 = Gomez|first1 = Melissa}}</ref>

|-
| September 26, 2020
| Lake Merrisach, Arkansas
| 425.45&nbsp;cm
| 362.874&nbsp;kg
| not listed
| not listed
| not listed
| <ref>{{cite web|url=https://www.5newsonline.com/article/sports/outdoors/arkansas-man-kills-alligator-dumas/91-3053dbe7-bdac-424f-bdb9-0caeae80435a|title=Longest alligator in Arkansas history killed in Dumas|date=September 27, 2020 }}</ref>

|-
| February 2, 2022
| Lake Washington, Florida
| 401.32&nbsp;cm
| 410.501&nbsp;kg
| not listed
| not listed
| not listed
| Killed by Doug Borries of Dynamic Outdoors TV after alligator began eating livestock.<ref>{{cite web|url=https://www.yahoo.com/sports/hunter-bags-905-pound-problem-190048136.html|title=Hunter bags 905-pound, problem-causing alligator; lively debate ensues|date=February 2, 2022 }}</ref>


|-
| August 29, 2023
| Yazoo River, Mississippi
| 434.34&nbsp;cm
| 364.00&nbsp;kg
| 167.64&nbsp;cm
| not listed
| 434.34&nbsp;cm
| <ref>{{cite web | url=https://www.independent.co.uk/news/world/americas/alligator-mississippi-state-record-yazoo-river-b2400676.html | title='Nightmare' giant alligator caught in Mississippi sets new records | website=[[Independent.co.uk]] | date=August 28, 2023 }}</ref><ref>{{cite news| last=Bella | first=Timothy | title=Record 14-foot monster alligator caught in Mississippi: 'It was pandemonium' |newspaper=The Washington Post | date=28 August 2023 | url=https://www.washingtonpost.com/nation/2023/08/28/mississippi-alligator-800-pounds-14-feet/ | access-date=25 February 2024}}</ref>
|}

====Average====
American alligators do not normally reach such extreme sizes. In mature males, most specimens grow up to about {{convert|3.4|m|ftin|abbr=on}} in length, and weigh up to {{convert|360|kg|lb|abbr=on}},<ref name="animalspot">{{cite web|url=http://www.animalspot.net/american-alligator.html|title=American Alligator|website=www.animalspot.net|date=June 16, 2012|language=en-US|access-date=April 24, 2017}}</ref> while in females, the mature size is normally around {{convert|2.6|m|ftin|abbr=on}}, with a body weight up to {{convert|91|kg|lb|abbr=on}}.<ref name="gatorfact">{{cite web |title=Gator factsheet |publisher=Savannah River Ecology Laboratory |url=http://srelherp.uga.edu/SPARC/PDFs/gator-fact-sheetA.pdf |access-date=August 14, 2012 |archive-date=May 12, 2013 |archive-url=https://web.archive.org/web/20130512090737/http://srelherp.uga.edu/SPARC/PDFs/gator-fact-sheetA.pdf }}</ref><ref name="nationalzoo">{{cite web |url=http://nationalzoo.si.edu/animals/reptilesamphibians/facts/factsheets/americanalligator.cfm |title=American Alligator Fact Sheet |publisher=The National Zoo |access-date=December 30, 2013}}</ref> In [[Newnans Lake]], Florida, adult males averaged {{convert|73.2|kg|lb|abbr=on}} in weight and {{convert|2.47|m|ftin|abbr=on}} in length, while adult females averaged {{convert|55.1|kg|lb|abbr=on}} and measured {{convert|2.22|m|ftin|abbr=on}}.<ref name=Goodwin>{{cite journal|last=Goodwin |first=Thomas M. |year=1979 |title=Seasonal activity ranges and habitat preferences of adult alligators in a north-central Florida lake |journal=Journal of Hepatology |volume=13 |issue=2 |pages=157–64 |jstor=1563922|doi=10.2307/1563922 |bibcode=1979JHerp..13..157G }}</ref> In [[Lake Griffin State Park]], Florida, adults weighed on average {{convert|57.9|kg|lb|abbr=on}}.<ref>{{cite journal | last1 = Honeyfield | first1 = D. C. | last2 = Ross | first2 = J. P. | last3 = Carbonneau | first3 = D. A. | last4 = Terrell | first4 = S. P. | last5 = Woodward | first5 = A. R. | last6 = Schoeb | first6 = T. R. | last7 = Hinterkopf | first7 = J. P. | year = 2008 | title = Pathology, physiologic parameters, tissue contaminants, and tissue thiamine in morbid and healthy central Florida adult American alligators (''Alligator mississippiensis'') | journal = Journal of Wildlife Diseases | volume = 44 | issue = 2| pages = 280–294 | doi=10.7589/0090-3558-44.2.280| pmid = 18436661 | doi-access = free }}</ref> Weight at sexual maturity per one study was stated as averaging {{convert|30|kg|lb|abbr=on}} while adult weight was claimed as {{convert|160|kg|lb|abbr=on}}.<ref>{{cite journal | last1 = Ruben | first1 = J. A. | last2 = Jones | first2 = T. D. | year = 2000 | title = Selective factors associated with the origin of fur and feathers | journal = American Zoologist | volume = 40 | issue = 4| pages = 585–596 | doi=10.1668/0003-1569(2000)040[0585:sfawto]2.0.co;2| s2cid = 55795562 }}</ref>

====Relation to age====
There is a common presumption stated throughout reptilian literature that crocodilians, including the American alligator, exhibit [[indeterminate growth]], meaning the animal continues to grow for the duration of its life. However, these claims are largely based on assumptions and observations of juvenile and young adult crocodilians, and recent studies are beginning to contradict this claim. For example, one long-term mark-recapture study (1979–2015) done at the [[Tom_Yawkey#Tom_Yawkey_Wildlife_Center_Heritage_Preserve|Tom Yawkey Wildlife Center]] in [[South Carolina]] found evidence to support patterns of determinate growth, with growth ceasing upon reaching a certain age (43 years for males and 31 years for females).<ref name="Wilkinson2016">{{Cite journal |last1=Wilkinson |first1=Philip M. |last2=Rainwater |first2=Thomas R. |last3=Woodward |first3=Allan R. |last4=Leone |first4=Erin H. |last5=Carter |first5=Cameron |date=November 2016 |title=Determinate Growth and Reproductive Lifespan in the American Alligator (Alligator mississippiensis): Evidence from Long-term Recaptures |url=https://bioone.org/journals/copeia/volume-104/issue-4/CH-16-430/Determinate-Growth-and-Reproductive-Lifespan-in-the-American-Alligator-Alligator/10.1643/CH-16-430.full |journal=Copeia |volume=104 |issue=4 |pages=843–852 |doi=10.1643/CH-16-430 |bibcode=2016Copei.104..843W |s2cid=89048080 |issn=0045-8511|url-access=subscription }}</ref>

====Sexual dimorphism====
While noticeable in very mature specimens, the [[sexual dimorphism]] in size of the American alligator is relatively modest among crocodilians.<ref>{{cite journal | last1 = Saalfeld | first1 = D. T. | last2 = Webb | first2 = K. K. | last3 = Conway | first3 = W. C. | last4 = Calkins | first4 = G. E. | last5 = Duguay | first5 = J. P. | year = 2008 | title = Growth and condition of American alligators (''Alligator mississippiensis'') in an inland wetland of east Texas | journal = Southeastern Naturalist | volume = 7 | issue = 3| pages = 541–550 | doi=10.1656/1528-7092-7.3.541| s2cid = 84645749 }}</ref> For contrast, the sexual dimorphism of [[saltwater crocodile]]s is much more extreme, with mature males nearly twice as long as and at least four times as heavy as female saltwater crocodiles.<ref>{{cite journal | last1 = Webb | first1 = GJW. | last2 = Messel | first2 = H. | s2cid = 56360888 | year = 1978 | title = Morphometric analysis of Crocodylus porosus from the north coast of Arnhem Land, northern Australia | doi = 10.1071/zo9780001 | journal = Australian Journal of Zoology | volume = 26 | issue = 1| pages = 1–27 | bibcode = 1978AuJZ...26....1W }}</ref> Given that female American alligators have relatively higher survival rates at an early age and a large percentage of given populations consists of immature or young breeding American alligators, relatively few large mature males of the expected mature length of {{convert|3.4|m|ftin|abbr=on}} or more are typically seen.<ref>{{cite journal | last1 = Lance | first1 = V. A. | last2 = Elsey | first2 = R. M. | last3 = Lang | first3 = J. W. | year = 2000 | title = Sex ratios of American alligators (Crocodylidae): male or female biased? | journal = Journal of Zoology | volume = 252 | issue = 1| pages = 71–78 | doi=10.1017/s0952836900009080}}</ref>

===Color===
Dorsally, adult American alligators may be olive, brown, gray, or black. However, they are on average one of the most darkly colored modern crocodilians (although other alligatorid family members are also fairly dark), and can reliably be distinguished by color via their more blackish dorsal scales against [[American crocodile|crocodiles]].<ref name= Ross/> Meanwhile, their undersides are cream-colored.<ref>{{cite web|title=American Alligator: Species Profile|publisher=US National Park Service|access-date=August 14, 2012|url=https://home.nps.gov/ever/learn/nature/alligator.htm}}</ref> Some American alligators are missing or have an inhibited [[gene]] for [[melanin]], which makes them [[albinism|albino]]. These American alligators are extremely rare and almost impossible to find in the wild. They could only survive in captivity, as they are very vulnerable to the sun and predators.<ref>{{cite web|url=https://www.nbcnews.com/id/wbna18620211|title=Zoo keeps albino alligator in the dark |publisher=NBC News.com |date=May 11, 2007 |access-date=August 15, 2012}}</ref>

===Jaws, teeth, and snout===
[[File:AmericanAlligator3.jpg|thumbnail|American alligator showing teeth]]
[[File:American alligator (Alligator mississippiensis) skull nostrils at the Royal Veterinary College anatomy museum.JPG|thumb|The snout of an American alligator skull]]
American alligators have 74–80 teeth.<ref name = "ufl"/> As they grow and develop, the morphology of their teeth and jaws change significantly.<ref name=":0">{{Cite journal|last1=Erickson|first1=Gregory M.|last2=Lappin|first2=A. Kristopher|last3=Vliet|first3=Kent A.|s2cid=241524|date=March 2003|title=The ontogeny of bite-force performance in American alligator (Alligator mississippiensis)|journal=Journal of Zoology|volume=260|issue=3|pages=317–327|doi=10.1017/s0952836903003819|issn=0952-8369}}</ref> Ventral pterygoideus muscles are enlarged and extremely powerful.<ref>{{Cite journal |last1=Gignac |first1=P. M. |last2=Erickson |first2=G. M. |date=2016 |title=Ontogenetic bite-force modeling of Alligator mississippiensis: implications for dietary transitions in a large-bodied vertebrate and the evolution of crocodylian feeding |url=https://zslpublications.onlinelibrary.wiley.com/doi/10.1111/jzo.12349 |journal=Journal of Zoology |language=en |volume=299 |issue=4 |pages=229–238 |doi=10.1111/jzo.12349 |issn=1469-7998|url-access=subscription }}</ref> Juveniles have small, needle-like teeth that become much more robust and narrow snouts that become broader as the individuals develop.<ref name=":0" /> These morphological changes correspond to shifts in the American alligators' diets, from smaller prey items such as fish and insects to larger prey items such as turtles, birds, and other large vertebrates.<ref name=":0" /> American alligators have broad snouts, especially in captive individuals. When the jaws are closed, the edges of the upper jaws cover the lower teeth, which fit into the jaws' hollows. Like the [[spectacled caiman]], this species has a bony nasal ridge, though it is less prominent.<ref name = "ufl"/> American alligators are often mistaken for a similar animal: the American crocodile. An easy characteristic to distinguish the two is the fourth tooth. Whenever an American alligator's mouth is closed, the fourth tooth is no longer visible. It is enclosed in a pocket in the upper jaw. American alligators also frequently lose and replace their teeth, about once every year.<ref>{{cite journal |last1=Wu |first1=Ping |last2=Wu |first2=Xiaoshan |last3=Jiang |first3=Ting-Xin |last4=M. Elsey |first4=Ruth |last5=L. Temple |first5=Bradley |last6=J. Divers |first6=Stephen |last7=C. Glenn |first7=Travis |last8=Yuan |first8=Kuo |last9=Chen |first9=Min-Huey |last10=B. Widelitz |first10=Randall |last11=Chuong |first11=Cheng-Ming |title=Specialized stem cell niche enables repetitive renewal of alligator teeth |journal=PNAS |date=13 May 2013 |volume=110 |issue=22 |pages=E2009–E2018 |doi=10.1073/pnas.1213202110 |pmid=23671090 |doi-access=free |pmc=3670376 |bibcode=2013PNAS..110E2009W }}</ref> As American alligators live a lengthy life, they can go through over 2,000 teeth in their lifetimes.<ref>{{cite web |title=AnimalHub: Discover fascinating facts about American Alligator |url=https://animalhub.earth/animals/american-alligator/fascinating-facts |website=AnimalHub |access-date=19 February 2025}}</ref>

===Bite===
Adult American alligators held the record as having the strongest laboratory-measured bite of any living animal, measured at up to {{convert|13172|N|kgf lbf|abbr=on|lk=on}}. This experiment had not been, at the time of the paper published, replicated in any other crocodilians, and the same laboratory was able to measure a greater bite force of {{convert|16414|N|kgf lbf|abbr=on}} in [[saltwater crocodile]]s;<ref name="lappin">{{cite journal |title=Comparison of bite-force performance between long-term captive and wild American alligators (Alligator mississippiensis) |journal=[[Journal of Zoology]] |volume=262 |issue=1 |pages=21–28 |url=http://www.alligatorfarm.us/images/Research/Erickson%20et%20al.%202004.pdf|doi=10.1017/S0952836903004400 |year=2004 |last1=Erickson |first1=Gregory M. |last2=Lappin |first2=A. Kristopher |last3=Parker |first3= Trevor |last4=Vliet |first4=Kent A. |bibcode=2004JZoo..262...21E }}</ref><ref name="erickson">{{cite journal|last=Erickson|first=GM|author2=Gignac PM |author3=Steppan SJ |author4=Lappin AK |author5=Vliet KA |year=2012|title=Insights into the Ecology and Evolutionary Success of Crocodilians Revealed through Bite-Force and Tooth-Pressure Experimentation|journal=PLOS ONE|volume=7|issue=3|article-number=e31781|doi=10.1371/journal.pone.0031781|pmid=22431965|pmc=3303775|display-authors=etal|bibcode=2012PLoSO...731781E|doi-access=free}}</ref> notwithstanding this very high biting force, the muscles opening the American alligator's jaw are quite weak, and the jaws can be held closed by hand or tape when an American alligator is captured. No significant difference is noted between the bite forces of male and female American alligators of equal size.<ref name=":0" /> Another study noted that as the American alligator increases in size, the force of its bite also increases.<ref>Erickson, G. M., Lappin, A. K., & Vliet, K. A. (2003). The ontogeny of bite-force performance in American alligator (Alligator mississippiensis). Journal of Zoology, 260(3), 317–327		</ref>

===Movement===
[[File:AmericanAlligator77.JPG|thumb|"High walk" of an American alligator]]
[[File:X-ray video of a female American alligator (Alligator mississippiensis) while breathing - pone.0004497.s009.ogv|thumb|[[X-ray]] video of a female American alligator showing contraction of the lungs while [[breathing]]]]
When on land, an American alligator moves either by sprawling or walking, the latter involving the reptile lifting its belly off the ground. The sprawling of American alligators and other crocodylians is not similar to that of salamanders and lizards, being similar to walking. Therefore, the two forms of land locomotion can be termed the "low walk" and the "high walk". Unlike most other land vertebrates, American alligators increase their speed through the distal rather than proximal ends of their limbs.<ref>{{cite journal|last1=Reilly |first1=S. M. |last2=Elias |first2=J. A. |year=1998 |title=Locomotion in alligator mississippiensis: kinematic effects of speed and posture and their relevance to the sprawling-to-erect paradigm |journal=[[The Journal of Experimental Biology]] |volume=201 |issue=18 |pages=2559–74 |doi=10.1242/jeb.201.18.2559 |pmid=9716509 |url=http://jeb.biologists.org/content/201/18/2559.full.pdf |doi-access=free |bibcode=1998JExpB.201.2559R }}</ref> 

In the water, American alligators swim like fish, moving their pelvic regions and tails from side to side.<ref>{{cite journal |last=Fish |first=F. E. |year=1984 |title=Kinematics of undulatory swimming in the American alligator |journal=Copeia |pages=839–43 |url=http://darwin.wcupa.edu/~biology/fish/pubs/pdf/1984CopeiaKinematics.pdf |doi=10.2307/1445326 |volume=1984 |issue=4 |jstor=1445326 |archive-url=https://web.archive.org/web/20131021220152/http://darwin.wcupa.edu/~biology/fish/pubs/pdf/1984CopeiaKinematics.pdf |archive-date=October 21, 2013 }}</ref> Swimming is assisted by webbed rear feet as well, which bear four toes in contrast to the five toes of the front feet.<ref>{{cite web|url=https://www.fws.gov/species/american-alligator-alligator-mississippiensis|title=American Alligator|website=U.S. Fish & Wildlife Service|access-date=1 September 2024}}</ref><ref>{{cite web|url=https://www.nwf.org/Educational-Resources/Wildlife-Guide/Reptiles/American-Alligator|title=American Alligator|website=National Wildlife Federation|access-date=1 September 2024}}</ref>  During respiration, air flow is unidirectional, looping through the lungs during inhalation and exhalation;<ref name=FK10>{{Cite journal |last1=Farmer |first1=C. G. |last2=Sanders |first2=K. |s2cid=206522844 |year=2010 |title=Unidirectional airflow in the lungs of American alligators |journal=Science |volume=327 |issue=5963 |pages=338–340 |doi=10.1126/science.1180219 |pmid=20075253|bibcode=2010Sci...327..338F }}</ref> the American alligator's abdominal muscles can alter the position of the lungs within the torso, thus shifting the center of buoyancy, which allows the American alligator to dive, rise, and roll within the water.<ref name="uriona">{{cite journal |title=Recruitment of the diaphragmaticus, ischiopubis and other respiratory muscles to control pitch and roll in the American alligator (''Alligator mississippiensis'') |journal=[[Journal of Experimental Biology]] |volume=211 |issue=7 |pages=1141–11477 |doi=10.1242/jeb.015339 |year=2008 |last1=Uriona |first1=T. J. |last2=Farmer |first2= C. G. |pmid=18344489|doi-access=free |bibcode=2008JExpB.211.1141U }}</ref>

== Distribution ==
[[File:Crocodile and Gator at Mrazek Pond (2), EVER, NPSPhoto, SCotrell, 4-2011 (9255694189).jpg|thumb|right|American alligator (right) and [[American crocodile]] (left) at Mrazek Pond, Florida]]
American alligators, being native both to the [[Nearctic]] and [[Neotropical]] [[biogeographic realm|realm]]s, are found in the wild in the [[Southeastern United States]], from the [[Lowcountry]] in [[South Carolina]], south to [[Everglades National Park]] in Florida, and west to [[South Texas]].<ref name="researchgate.net">{{cite web|last=Sigler|first=Luis|date=September 2007|title=Searching for the northern and southern distribution limits of two crocodilian species: Alligator mississippiensis and Crocodylus moreletii in South Texas, US, and in northern Tamaulipas, Mexico.|url=https://www.researchgate.net/publication/305721061|access-date=May 12, 2018}}</ref> They are found in parts of [[North Carolina]], South Carolina, [[Georgia (U.S. state)|Georgia]], Florida, Louisiana, [[Alabama]], [[Mississippi]], [[Arkansas]], [[Oklahoma]], and [[Texas]]. Some of these locations appear to be relatively recent introductions, with often small but reproductive populations.<ref>{{cite web|url=https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=221 |title=NAS - Nonindigenous Aquatic Species: Alligator mississippiensis|website=USGS}}</ref> Louisiana has the largest American alligator population of any U.S. state. In the future, possible American alligator populations may be found in areas of [[Mexico]] adjacent to the Texas border.<ref>{{cite web|url=https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=221 |title=American alligator (Alligator mississippiensis) - Species Profile |publisher=Nas.er.usgs.gov |date= |access-date=2022-03-16}}</ref> The range of the American alligator is slowly expanding northwards, including into areas they once found unsuitable, such as Virginia.<ref>{{Cite web |date=2023-12-19 |title=Why We Almost Said "See You Later" to the American Alligator {{!}} Defenders of Wildlife |url=https://defenders.org/blog/2023/12/why-we-almost-said-see-you-later-american-alligator |access-date=2024-08-03 |website=defenders.org |language=en}}</ref> American alligators have been naturally expanding their range into [[Tennessee]],<ref>{{Cite web |title=Alligators have been sighted in Tennessee |url=https://www.tn.gov/twra/wildlife/reptiles/alligators.html |access-date=2022-08-02 |website=www.tn.gov |language=en}}</ref> and have established a small population in the southwestern part of that state via inland waterways, according to the state's wildlife agency.<ref>{{Cite web |last=Outdoors |first=Grand View |date=2019-07-02 |title=Alligators Expanding Range, Confirmed in… |url=https://www.grandviewoutdoors.com/news/alligators-expanding-range-confirmed-in-tennessee |access-date=2022-08-02 |website=Grand View Outdoors |language=en}}</ref> They have been [[extirpated]] from [[Virginia]], and occasional [[Vagrancy (biology)|vagrants]] from North Carolina wander into the [[Great Dismal Swamp]].<ref>{{cite web |author=VLM Staff |date=April 30, 2016 |title=Herp Highlight #1: American Alligator |url=https://thevlm.org/herp-highlight-1-american-alligator/ |access-date=April 8, 2021 |work=TheVLM.org |publisher=Virginia Living Museum (VLM)}}</ref> 

In 2021, an individual was found in [[Calvert County, Maryland|Calvert County]], [[Maryland]], near [[Chesapeake Bay]], where it was shot and killed by a hunter using a [[crossbow]]. Additional reports of American alligators from this region exist, though they are believed to be escaped or released exotic pets.<ref>{{Cite web |last=Bulletin |first=Bay |date=2021-06-22 |title=Calvert Man Recounts How He Caught 7.5-Foot Alligator from Chesapeake Bay |url=https://www.chesapeakebaymagazine.com/calvert-co-man-claims-7-5-foot-alligator-caught-from-chesapeake-bay/ |access-date=2024-08-03 |website=Chesapeake Bay Magazine |language=en-US}}</ref>

== Conservation status ==
[[File:LeucisticAlligator.jpg|thumb|A [[leucistic]] American alligator at [[Gatorland]]]]
American alligators are listed as [[Least-concern species|least concern]] by the [[IUCN Red List]],<ref name=iucn/> even though from the 19th century to the mid-20th century, they were being hunted and poached by humans unsustainably.

Historically, hunting and habitat loss have severely affected American alligator populations throughout their range, and whether the species would survive was in doubt. In 1967, the American alligator was listed as an endangered species (under a law that was the precursor to the [[Endangered Species Act]] of 1973), since it was believed to be in danger of [[extinction]] throughout all or a significant portion of its range.<ref name="ufws">{{cite web|date=February 2008|title=American Alligator ''Alligator mississippiensis''|url=http://www.fws.gov/endangered/esa-library/pdf/alligator.pdf|archive-url=https://web.archive.org/web/20200702034410/https://www.fws.gov/endangered/esa-library/pdf/alligator.pdf|archive-date=2 July 2020|publisher=U.S. Fish and Wildlife Service}}</ref>

Both the [[United States Fish and Wildlife Service]] (USFWS) and state wildlife agencies in the [[Southern United States|South]] contributed to the American alligator's recovery. Protection under the Endangered Species Act allowed the species to recuperate in many areas where it had been depleted. States began monitoring their American alligator populations to ensure that they would continue to grow. In 1987, the USFWS removed the animal from the endangered species list, as it was considered to be fully recovered.<ref>[https://www.captainjacksairboattours.com/7-are-alligators-endangered/ captain jacks air boat tours] Retrieved June 26, 2020.</ref> The USFWS still regulates the legal trade in American alligators and their products to protect still endangered crocodilians that may be passed off as American alligators during trafficking.<ref name="ufws" />

American alligators are listed under Appendix II of the [[Convention on International Trade in Endangered Species]] (CITES) meaning that international trade in the species (including parts and derivatives) is regulated.<ref name = "CITES"/>

==Habitat==
[[File:Alligatoridae - Alligator mississippiensis from Everglades.webm|thumb|alt=muted|American alligator in the Everglades]]American alligators inhabit swamps, streams, rivers, ponds, and lakes as well as wetland prairies interspersed with shallow open water and canals with associated levees.<ref>{{Cite journal |last1=WEBB |first1=KEVIN K. |last2=CONWAY |first2=WARREN C. |last3=CALKINS |first3=GARY E. |last4=DUGUAY |first4=JEFFREY P. |date=May 2009 |title=Habitat Use of American Alligators in East Texas |journal=The Journal of Wildlife Management |volume=73 |issue=4 |pages=566–572 |doi=10.2193/2006-294 |bibcode=2009JWMan..73..566W |issn=0022-541X}}</ref> A lone American alligator was spotted for over 10 years living in a river north of Atlanta, Georgia.<ref>{{Cite news|url=http://www.myajc.com/news/hooch-gator-trapped/Dty4FQvuIqEEc2IhC9yqTI/|title=Elusive Chattahoochee alligator caught in Cobb County|newspaper=myajc|access-date=December 17, 2016}}</ref> Females and juveniles are also found in [[Carolina Bay]]s and other seasonal wetlands. While they prefer fresh water, American alligators may sometimes wander into [[brackish]] water,<ref name=srel>{{cite web|title=American Alligator (''Alligator mississippiensis'')|publisher=Savannah River Ecology Lab|access-date=August 16, 2012|url=http://srelherp.uga.edu/alligators/allmis.htm|archive-date=March 28, 2023|archive-url=https://web.archive.org/web/20230328011456/http://srelherp.uga.edu/alligators/allmis.htm}}</ref> but are less tolerant of salt water than American crocodiles, as the [[salt glands]] on their tongues do not function.<ref>{{cite web|title=What's the difference between a crocodile and an alligator?|publisher=Flmnh.ufl.edu.|access-date=August 26, 2012|url=http://crocodilian.com/cnhc/cbd-faq-q1.htm|archive-date=October 11, 2012|archive-url=https://web.archive.org/web/20121011223513/http://crocodilian.com/cnhc/cbd-faq-q1.htm}}</ref> One study of American alligators in north-central Florida found the males preferred open lake water during the spring, while females used both swampy and open-water areas. During summer, males still preferred open water, while females remained in the swamps to construct their nests and lay their eggs. Both sexes may den underneath banks or clumps of trees during the winter.<ref name=Goodwin />

In some areas of their range, American alligators are an unusual example of [[urban wildlife]]; golf courses are often favored by the species due to an abundance of water and a frequent supply of prey animals such as fish and birds.<ref>{{cite web|date=2015-03-12|title=Alligator hazard is par for the course at Florida golf club|url=http://www.theguardian.com/us-news/2015/mar/12/alligator-florida-golf-club-par-for-the-course|access-date=2022-01-20|website=The Guardian|language=en}}</ref><ref>{{cite news|date=2020-11-12|title=Enormous alligator spotted on Florida golf course|url=https://www.independent.co.uk/news/world/americas/alligator-florida-naples-golf-course-b1721855.html |archive-url=https://web.archive.org/web/20201113070828/https://www.independent.co.uk/news/world/americas/alligator-florida-naples-golf-course-b1721855.html |archive-date=2020-11-13 |url-access=limited |url-status=live|access-date=2022-01-20|website=The Independent|language=en}}</ref>

Recent research on juvenile American alligators has found that young alligators can adjust behavior in reaction to stressful environments, particularly with higher salt levels. Rather than adapting physically, juveniles have been shown to change their everyday habits – things like basking in the sun or moving between habitats – to avoid dehydration from salt water <ref>Faulkner, P. C., Hala, D., Shimskie, J., Johnson, R., Schneider, A., Cubbage, T., Lozano, N., & Petersen, L. H. (2023). Juvenile American alligators (Alligator mississippiensis) use behavioral Thermoregulation to cope with dehydration and salt-loading when chronically exposed to 12 ‰ saltwater. ''Animal Behavior and Cognition'', ''10''(1), 1-13. <nowiki>https://doi.org/10.26451/abc.10.01.01.2023</nowiki></ref>. As sea levels continue to rise, it is especially important that alligators can adapt and maintain regular body function, despite changing environments. 

===Cold tolerance===
American alligators are less vulnerable to cold than [[American crocodile]]s. Unlike an American crocodile, which would immediately succumb to the cold and drown in water at {{convert|45|F|C}} or less, an American alligator can survive in such temperatures for some time without displaying any signs of discomfort.<ref name="Guggisberg">{{cite book | author = Guggisberg, C.A.W. | title = Crocodiles: Their Natural History, Folklore, and Conservation| year = 1972 | page = 195 | isbn = 978-0-7153-5272-4 | publisher = David & Charles | location = Newton Abbot}}</ref> This adaptiveness is thought to be why American alligators are widespread further north than the American crocodile.<ref name="Guggisberg"/> In fact, the American alligator is found farther from the equator and is more equipped to handle 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 |pmid=12855291 |s2cid=31045078 }}</ref> When the water begins to freeze, American alligators go into a period of [[dormancy|brumation]]; they stick their snouts through the surface, which allows them to breathe above the ice,<ref name=srel/> and they can remain in this state for several days.<ref>{{cite web|last=Bryner |first=Jeanna |title=How Alligators Survive in a Frozen Pond: They 'Snorkel'|url=https://www.livescience.com/64592-alligators-weird-snout-behavior-winter.html|access-date=2020-08-15|website=livescience.com|date=January 25, 2019 |language=en}}</ref>

==Ecology and behavior==
[[File:Alligator mississippiensis (American alligator) 6.jpg|thumb|An American alligator basks on the bank of a pond in [[Big Cypress National Preserve]].]]
===Basking===
American alligators primarily [[Sunning (behaviour)|bask]] on shore, but also climb into and perch on tree limbs to bask if no shoreline is available. This is not often seen, since if disturbed, they quickly retreat back into the water by jumping from their perch.<ref>{{Cite journal|url=http://www.herpetologynotes.seh-herpetology.org/Volume7_PDFs/Dinets_HerpetologyNotes_volume7_pages3-7.pdf|title=Climbing behaviour in extant crocodilians |last1=Dinets |first1=Vladimir |last2=Britton |first2=Adam |last3=Shirley |first3=Matthew |year=2013 |journal=Herpetology Notes |volume=7 |pages=3–7}} (published online January 25, 2014)</ref>

===Holes===

American alligators modify wetland habitats, most dramatically in flat areas such as the Everglades, by constructing small ponds known as alligator holes. This behavior has qualified the American alligator to be considered a [[keystone species]]. Alligator holes retain water during the dry season and provide a refuge for aquatic organisms, which survive the dry season by seeking refuge in alligator holes, so are a source of future populations. The construction of nests along the periphery of alligator holes, as well as a buildup of soils during the excavation process, provides drier areas for other reptiles to nest and a place for plants that are intolerant of inundation to colonize. Alligator holes are an oasis during the Everglades dry season, so are consequently important foraging sites for other organisms.<ref>{{cite web |last1=Rice |first1=Ken G. |last2=Mazzotti |first2=Frank |title=American Alligator Ecology and Monitoring for the Comprehensive Everglades Restoration Plan |date=October 2005 |url=http://edis.ifas.ufl.edu/pdffiles/UW/UW23200.pdf |publisher=University of Florida IFAS Extension}}</ref> In the limestone depressions of [[Taxodium|cypress]] swamps, alligator holes tend to be large and deep, while those in [[Everglades National Park#Freshwater sloughs and marl prairies|marl prairies]] and rocky glades are usually small and shallow, and those in [[peat]] depressions of ridge and slough wetlands are more variable.<ref>{{cite journal|last1=Campell |first1=Mark R. |last2=Mazzotti |first2=Frank J. |year=2004 |title=Characterization of Natural and Artificial Alligator Holes |journal=Southeastern Naturalist |volume=3 |issue=4 |pages=583–94 |doi=10.1656/1528-7092(2004)003[0583:CONAAA]2.0.CO;2 |jstor=3878020 |s2cid=85653669 }}</ref> When alligators dig nesting holes, raised soil creates refuges that can be used by reptiles and birds for nests during flood season, as well as increasing plant germination in areas that are prone to flooding <ref>{{Cite journal |last1=Harvey |first1=Rebecca G. |last2=Mazzotti |first2=Frank J. |last3=Brandt |first3=Laura A. |date=2011-11-30 |title=The American Alligator: An Indicator Species for Everglades Restoration: WEC313/UW358, 10/2011 |url=https://journals.flvc.org/edis/article/view/119421 |journal=EDIS |language=en |volume=2011 |issue=11 |doi=10.32473/edis-uw358-2011 |issn=2576-0009|doi-access=free }}</ref>. The American alligator is a foundational species in the everglades, acting as "ecological engineers" that helps the ecosystem prosper. 

===Feeding===
<gallery mode="packed" heights="80">
File:American Alligator, Chambers County, TX, USA imported from iNaturalist photo 303450133.jpg|Eating a [[Florida gar]]
File:See You Later, Alligator . ..jpg|Eating a [[Loricariidae|pleco]]
File:American Alligator eating Blue Crab 2.JPG|Eating a [[Portunidae|swimmer crab]]
File:American Alligator, Gulf State Park, Gulf Shores, AL, US imported from iNaturalist photo 58085636.jpg|Eating a [[Redhead (bird)|redhead duck]]
File:American Alligator, Big Cypress National Preserve, Ochopee, FL, US imported from iNaturalist photo 345267533.jpg|Eating a [[great blue heron]]
File:American Alligator, Brazoria County, TX, USA imported from iNaturalist photo 283873098.jpg|Eating a [[feral pig]]
File:Gator and Python.jpg|Killing an invasive [[Burmese python]], which is attempting to coil around it
</gallery>

====Bite and mastication====
The teeth of the American alligator are designed to grip prey, but cannot rip or chew flesh like teeth of some other predators (such as [[canid]]s and [[felid]]s), and depend on their [[gizzard]], instead, to masticate their food. The attainment of adulthood enables the consumption of large mammals and the crushing of large turtles.<ref>{{Cite journal |last1=Erickson |first1=Gregory M. |last2=Lappin |first2=A. Kristopher |last3=Vliet |first3=Kent A. |date=July 2003 |title=The ontogeny of bite-force performance in American alligator (''Alligator mississippiensis'') |journal=Journal of Zoology |volume=260 |issue=3 |pages=317–327 |doi=10.1017/s0952836903003819 |issn=0952-8369}}</ref> The American alligator is capable of biting through a turtle's shell or a moderately sized mammal bone.<ref name= University>[http://edis.ifas.ufl.edu/uw230 WEC203/UW230: Living with Alligators: A Florida Reality]. Edis.ifas.ufl.edu. Retrieved on August 21, 2012.</ref> Additionally, the palate of American alligators enables them to capture prey underwater without flooding their respiratory system with water<ref>{{Cite journal |last=Ferguson |first=M. W. J. |date=1981-01-01 |title=The structure and development of the palate in Alligator mississippiensis |url=https://linkinghub.elsevier.com/retrieve/pii/0003996981900418 |journal=Archives of Oral Biology |volume=26 |issue=5 |pages=427–443 |doi=10.1016/0003-9969(81)90041-8 |pmid=6947744 |issn=0003-9969|url-access=subscription }}</ref>

====Possible tool use====
American alligators have been documented using lures to hunt prey such as birds.<ref name="Dinets et al. 2014">{{cite journal|first1=V|last1=Dinets|first2=JC|last2=Brueggen|first3=J.D.|last3=Brueggen |title=Crocodilians use tools for hunting|journal=Ethology, Ecology and Evolution |year=2014 |volume=27 |doi=10.1080/03949370.2013.858276 |pages=74–78 |s2cid=84655220}}</ref> This means they are among the first reptiles recorded to [[tool use by non-humans|use tools]]. By balancing sticks and branches on their heads, American alligators are able to lure birds looking for suitable nesting material to kill and consume. This strategy, which is shared by the [[mugger crocodile]], is particularly effective during the nesting season, in which birds are more likely to gather appropriate nesting materials.<ref>{{cite web|url=https://www.sciencedaily.com/releases/2013/12/131204182433.htm|title=Crocodiles are cleverer than previously thought: Some crocodiles use lures to hunt their prey|website=ScienceDaily|date=December 4, 2013|access-date=December 8, 2013}}</ref> This strategy has been documented in two Florida zoos occurring multiple times a day in peak nesting season and in some parks in Louisiana. The use of tools was documented primarily during the peak rookery season when birds were primarily looking for sticks.<ref name="Dinets et al. 2014"/>

However, a three-day experiment to reproduce the use of sticks as lures, published in 2019, failed to document the behavior. Researchers placed sticks at densities of 30 to 35 sticks per meter squared near four captive populations, two near [[rookeries]] and two at no-rookery sites. While stick-displaying behavior was observed several times, it was not more frequent near rookeries. In fact, in some comparisons, it was associated with no-rookery sites. This implies American alligators do not tailor this behavior to specific contexts, leaving the purpose, if any, of stick-displaying ambiguous.<ref>{{Cite journal |last1=Rosenblatt |first1=Adam E. |last2=Johnson |first2=Alyssa |date=2019-11-26 |title=An experimental test of crocodilian stick-displaying behavior |url=https://www.tandfonline.com/doi/full/10.1080/03949370.2019.1691057 |journal=Ethology Ecology & Evolution |language=en |volume=32 |issue=3 |pages=218–226 |doi=10.1080/03949370.2019.1691057 |issn=0394-9370|url-access=subscription }}</ref>

====Aquatic vs terrestrial prey====
Fish and other aquatic prey taken in the water or at the water's edge form the major part of American alligator's diet and may be eaten at any time of the day or night. Adult American alligators also spend considerable time hunting on land, up to {{convert|50|m|ft|order=flip}} from water, ambushing terrestrial animals on trailsides and road shoulders. Usually, terrestrial hunting occurs on nights with warm temperatures.<ref>{{cite journal |last=Dinets |first=V. L. |year=2011 |title=On terrestrial hunting in crocodilians |volume=114 |journal=Herpetological Bulletin |pages=15–18 |url=http://dinets.travel.ru/Pages%20from%20Bulletin%20114%20Dinets.pdf |archive-url=https://web.archive.org/web/20111015150803/http://dinets.travel.ru/Pages%20from%20Bulletin%20114%20Dinets.pdf |archive-date=October 15, 2011 }}</ref> When hunting terrestrial prey, American alligators may also ambush them from the edge of the water by grabbing them and pulling the prey into the water, the preferred method of predation of larger crocodiles.<ref name= Ross/>

Additionally, American alligators have recently been filmed and documented killing and eating sharks and rays; four incidents documented indicated that [[bonnethead]]s, [[lemon shark]]s, [[Atlantic stingray]]s, and [[nurse shark]]s are components of the animal's diet. Sharks are also known to prey on American alligators, in turn, indicating that encounters between the two predators are common.<ref>{{cite news|url=http://news.nationalgeographic.com/2017/09/american-alligator-sharks-predators-stingrays/|archive-url=https://web.archive.org/web/20170920232103/http://news.nationalgeographic.com/2017/09/american-alligator-sharks-predators-stingrays/|archive-date=September 20, 2017|title=Alligators Attack and Eat Sharks, Study Confirms|author=Jason Bittel|date=September 20, 2017|newspaper=National Geographic}}</ref><ref>{{cite journal|title=Reciprocal Intraguild Predation between Alligator mississippiensis (American Alligator) and Elasmobranchii in the Southeastern United States|journal=Southeastern Naturalist|volume=16|issue=3|year=2017|pages=383–396|first1=James C.|last1=Nifong|first2=Russell H.|last2=Lowers|doi=10.1656/058.016.0306|s2cid=90288005}}</ref>

====Common prey====
American alligators are considered an [[apex predator]] throughout their range. They are opportunists and their diet is determined largely by both their size and age and the size and availability of prey. Most American alligators eat a wide variety of animals, including [[invertebrate]]s, [[fish]], [[bird]]s, [[turtle]]s, [[snake]]s, [[amphibian]]s, and [[mammal]]s. Hatchlings mostly feed on invertebrates such as insects, insect [[larva]]e, [[snail]]s, [[spider]]s, and [[worm]]s, as well as small fish and [[frog]]s.<ref name="auto">{{cite web | url=https://animaldiversity.org/accounts/Alligator_mississippiensis/ | title=Alligator mississippiensis (Alligator, Gator, American alligator, Florida alligator, Mississippi alligator, Louisiana alligator.) | website=[[Animal Diversity Web]] }}</ref><ref>{{cite web | url=https://crocodilian.com/cnhc/csp_amis.htm | title=Crocodilian Species - American Alligator (Alligator mississippiensis) }}</ref> As they grow, American alligators gradually expand to larger prey. Once an American alligator reaches full size and power in adulthood, any animal living in the water or coming to the water to drink is potential prey. Most animals captured by American alligators are considerably smaller than itself.<ref name = "ufl"/> A few examples of animals consumed are [[largemouth bass]], [[spotted gar]], [[freshwater pearl mussel]]s, [[American green tree frog]]s, [[yellow mud turtle]]s, [[Agkistrodon piscivorus|cottonmouths]], [[common moorhen]]s, and feral [[wild boar]]s.<ref name="auto"/> Stomach contents show, among native mammals, [[muskrat]]s and [[raccoon]]s are some of the most commonly eaten species.<ref name= Valentine>{{cite journal | last1 = Valentine | first1 = J. M. Jr. | last2 = Walther | first2 = J. R. | last3 = McCartney | first3 = K. M. | last4 = Ivy | first4 = L. M. | year = 1972 | title = Alligator diets on the Sabine National Wildlife Refuge, Louisiana | journal = The Journal of Wildlife Management | volume = 36| issue = 3| pages = 809–815 | doi=10.2307/3799434| jstor = 3799434 | bibcode = 1972JWMan..36..809V }}</ref> In Louisiana, where introduced [[nutria]] are common, they are perhaps the most regular prey for adult American alligators, although only larger adults commonly eat this species.<ref name=r1/><ref name= Valentine/> It has also been reported that large American alligators prey on medium-sized American alligators, which had preyed on hatchlings and smaller juveniles.<ref>Rootes, W. L., & Chabreck, R. H. (1993). Cannibalism in the American alligator. Herpetologica,		99–107</ref> 

If an American alligator's primary food resource is not available, it will sometimes feed on [[carrion]] and non-prey items such as rocks and artificial objects, like bottle caps. These items help the American alligator in the process of digestion by crushing up the meat and bones of animals, especially animals with shells.<ref name="auto"/>

====Large animals====
Other animals may occasionally be eaten, even large [[deer]] or feral wild boars, but these are not normally part of the diet. American alligators occasionally prey on large mammals, but usually do so when fish and smaller prey levels go down.<ref name="American Alligator">{{cite web|title=American Alligator|work=ScienceDaily |url=https://www.sciencedaily.com/articles/a/american_alligator.htm|publisher=News Daily|access-date=February 28, 2018|archive-url=https://web.archive.org/web/20150318173004/http://www.sciencedaily.com/articles/a/american_alligator.htm|archive-date=March 18, 2015}}</ref> Rarely, American alligators have been observed killing and eating [[bobcat]]s, but such events are not common and have little effect on bobcat populations.<ref name="Gator eats bobcat">{{cite web|title=Gator eats bobcat|url=https://www.flickr.com/photos/feltonphoto/8164136944/|publisher=Flickr|access-date=November 7, 2012|date=2012-11-07}}</ref><ref name="Alligator nearly eats bobcat">{{cite web|title=Sneaky alligator nearly eats bobcat |url=http://www.kens5.com/video/featured-videos/Sneaky-alligator-nearly-eats-bobcat--156459515.html |publisher=Kens5 |access-date=June 1, 2012 |archive-url=https://web.archive.org/web/20140111043956/http://www.kens5.com/video/featured-videos/Sneaky-alligator-nearly-eats-bobcat--156459515.html |archive-date=January 11, 2014 }}</ref> Although American alligators have been listed as predators of the [[nilgai]] and the [[West Indian manatee]]s, very little evidence exists of such predation.<ref>Whitaker, John O. (1996). ''The Audubon Society Field Guide to North American Mammals.'' New York, pg. 808. {{ISBN|978-0-679-44631-6}}.</ref> In the 2000s, when invasive [[Burmese python]]s first occupied the Everglades, American alligators have been recorded preying on sizable snakes, possibly controlling populations and preventing the invasive species from spreading northwards.<ref>{{cite journal | last1 = Dorcas | first1 = M. E. | last2 = Willson | first2 = J. D. | last3 = Reed | first3 = R. N. | last4 = Snow | first4 = R. W. | last5 = Rochford | first5 = M. R. | last6 = Miller | first6 = M. A. | last7 = Hart | first7 = K. M. | year = 2012 | title = Severe mammal declines coincide with proliferation of invasive Burmese pythons in Everglades National Park | journal = Proceedings of the National Academy of Sciences | volume = 109 | issue = 7| pages = 2418–2422 | doi=10.1073/pnas.1115226109 | pmid=22308381 | pmc=3289325 | bibcode = 2012PNAS..109.2418D| doi-access = free }}</ref> However, the Burmese python is also known to occasionally prey on American alligators, a form of both [[competition (biology)|competition]] and [[predation]].<ref name=PMC3289325>{{cite journal | last1 = Nolen | first1 = R. S. | year = 2012 | title = How big is Florida's python problem? | journal = J Am Vet Med Assoc | volume = 240 | issue = 7| pages = 778–782 | pmid = 22443430 | doi = 10.2460/javma.240.7.778 }}</ref> American alligator predation on [[Florida panther]]s is rare, but has been documented. Such incidents usually involve a panther trying to cross a waterway or coming down to a swamp or river to get a drink.<ref>Sivlerstein, Alvin (1997). ''The Florida Panther''. Brooksville, Connecticut: Millbrook Press. pp. 41+. {{ISBN|0-7613-0049-X}}.</ref> American alligator predation on [[American black bear]]s has also been recorded.<ref>{{cite web|url=http://animallist.weebly.com/american-alligator.html|title=American Alligator|publisher=Animal List}}</ref><ref name="Alligators">{{cite web|url=http://www.aquaticcommunity.com/alligators/|title=Alligators|publisher=Aquatic Community}}</ref><ref name="Alligator Exhibit">{{cite web|url=http://www.keywestaquarium.com/alligator|title=Key West Florida Attractions {{!}} Alligator Exhibit|publisher=Key West Aquarium|access-date=December 20, 2012}}</ref>

====Domestic animals====
Occasionally, domestic animals, including [[dog]]s, [[cat]]s, and [[calf (animal)|calves]], are taken as available, but are secondary to wild and feral prey.<ref name = "ufl"/> Other prey, including snakes, lizards, and various invertebrates, are eaten occasionally by adults.<ref name="Ross"/>

====Birds====
[[Water bird]]s, such as [[heron]]s, [[egret]]s, [[stork]]s, [[Anatidae|waterfowl]] and large dabbling [[Rail (bird)|rails]] such as [[common gallinule|gallinules]] or [[American coot|coots]], are taken when possible. Occasionally, unwary adult birds are grabbed and eaten by American alligators, but most predation on bird species occurs with unsteady fledgling birds in late summer, as fledgling birds attempt to make their first flights near the water's edge.<ref name="Ross"/>
[[File:Gator Eats Pond Apple, NPSPhoto (9099194321).jpg|thumb|Eating a [[Annona glabra|pond apple]]]]

====Fruit====
In 2013, American alligators and other crocodilians were reported to also eat fruit.<ref>{{cite web |last=Choi |first=Charles Q. |date=August 30, 2013 |title=Crocodiles and alligators like to chomp down on&nbsp;... fruit ! |publisher=NBC News: Science |url=http://www.nbcnews.com/science/crocodiles-alligators-chomp-down-fruit-8C11044419 |access-date=August 31, 2013}}</ref> Such behavior has been witnessed, as well as documented from stomach contents, with the American alligators eating such fruit as wild [[grapes]], [[elderberries]], and [[citrus|citrus fruits]] directly from the trees. Thirty-four families and 46 genera of plants were represented among seeds and fruits found in the stomach contents of American alligators.<ref name="Platt et al. 2013">{{cite journal |last1=Platt |first1=S. G. |last2=Elsey |first2=R. M. |last3=Liu |first3=H. |last4=Rainwater |first4=T. R. |last5=Nifong |first5=J. C. |last6=Rosenblatt |first6=A. E. |last7=Heithaus |first7=M. R. |last8=Mazzotti |first8=F. J. |title=Frugivory and seed dispersal by crocodilians: an overlooked form of saurochory? |journal=Journal of Zoology |date=2013 |volume=291 |issue=2 |pages=87–99 |doi=10.1111/jzo.12052 |doi-access=free}}</ref> The discovery of this unexpected part of the American alligator diet further reveals that they may be responsible for spreading seeds from the fruit they consume across their habitat.<ref name="Platt et al. 2013"/> 

====Cooperative hunting====
Additionally, American alligators engage in what seems to be cooperative hunting.<ref>F. Wayne King, John Thorbjarnarson and Carlos Yamashita. 1998. Cooperative Feeding, A Misinterpreted and Under-Reported Behavior of Crocodilians. 9 p. Available at: http://www.flmnh.ufl.edu/herpetology/links/cooperative-feeding (Online: 1 August 1998)</ref><ref name="Dinets 2014">{{cite journal|first1=Vladmir|last1=Dinets|title=Apparent coordination and collaboration in cooperatively hunting crocodilians|journal=Ethology Ecology & Evolution|year=2014|volume=27|issue=2|pages=244–250|doi=10.1080/03949370.2014.915432|s2cid=84672219}}</ref> One observation of cooperative hunting techniques was where there are pushing American alligators and catching American alligators and they were observed taking turns in each position. Another observation said that about 60 American alligators gathered in an area and would form a semicircle with about half of them and would push the fish closer to the bank. Once one of the American alligators caught a fish another one would enter into its spot, and it would take the fish to the resting area. This was reported to have occurred two days in a row.<ref name="Dinets 2014"/>

====In Florida and East Texas====
The diet of adult American alligators from central Florida lakes is dominated by fish, but the species is highly opportunistic based upon local availability. In [[Lake Griffin State Park|Lake Griffin]], fish made up 54% of the diet by weight, with [[catfish]] being most commonly consumed, while in [[Lake Apopka]], fish made up 90% of the food and mostly [[shad]] were taken; in [[Lake Woodruff National Wildlife Refuge|Lake Woodruff]], the diet was 84% fish and largely consists of [[bass (fish)|bass]] and [[Centrarchidae|sunfish]]. Unusually in these regions, [[reptile]]s and [[amphibian]]s were the most important nonpiscivore prey, mostly turtles and [[Nerodia|water snakes]].<ref>Rice, A. N. (2004). ''Diet and condition of American alligators (''Alligator mississippiensis'') in three central Florida lakes'' (Doctoral dissertation, University of Florida).</ref> In southern Louisiana, [[crustacean]]s (largely [[crawfish]] and [[crab]]s) were found to be present in the southeastern American alligators, but largely absent in southwestern American alligators, which consumed a relatively high proportion of reptiles, although fish were the most recorded prey for adults, and adult males consumed a large portion of mammals.<ref>{{cite journal | last1 = Gabrey | first1 = S. W. | year = 2010 | title = Demographic and geographic variation in food habits of American alligators (''Alligator mississippiensis'') in Louisiana | url = http://www.herpconbio.org/Volume_5/Issue_2/Gabrey_2010.pdf| journal = Herpetological Conservation and Biology | volume = 5 | issue = 2| pages = 241–250 }}</ref>

In [[East Texas]], diets were diverse and adult American alligators took mammals, reptiles, amphibians, and [[invertebrate]]s (e.g. [[snail]]s) in often equal measure as they did fish.<ref>{{cite journal | last1 = Saalfeld | first1 = D. T. | last2 = Conway | first2 = W. C. | last3 = Calkins | first3 = G. E. | year = 2011 | title = Food Habits of American Alligators (''Alligator mississippiensis'') in East Texas | journal = Southeastern Naturalist | volume = 10 | issue = 4| pages = 659–672 | doi=10.1656/058.010.0406| s2cid = 85181112 }}</ref>

'''Human influence on feeding'''

Recent studies have shown that human altered environments – particularly golf courses – can have significant impacts on the diets of local alligators. Stomach content analysis revealed that in areas where humans manage the landscape more heavily, alligators often rely heavily on insects and spiders. Alligators in more natural environments, meanwhile, were found to consume more crustaceans and fish <ref>{{Cite journal |last1=Rosenblatt |first1=Adam E. |last2=Greco |first2=Robert |last3=Beal |first3=Eli |last4=Colbert |first4=Joseph |last5=Moore |first5=Yank |last6=Baglin |first6=Victoria |last7=Nifong |first7=James C. |date=2023 |title=Golf course living leads to a diet shift for American alligators |journal=Ecology and Evolution |language=en |volume=13 |issue=9 |article-number=e10495 |doi=10.1002/ece3.10495 |issn=2045-7758 |pmc=10468965 |pmid=37664492 |bibcode=2023EcoEv..1310495R }}</ref>. This research highlights how human development directly shapes foraging habits of American Alligators. 

===Vocalizations===
{{listen
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====Mechanism====
An American alligator is able to [[abduction (anatomy)|abduct]] and [[Adduction|adduct]] the [[vocal folds]] of its [[larynx]], but not to elongate or shorten them; yet in spite of this, it can modulate [[fundamental frequency]] very well.<ref>{{Cite journal|title=Subglottal pressure and fundamental frequency control in contact calls of juvenile ''Alligator mississippiensis'' |doi-access=free |journal=Journal of Experimental Biology|volume=214|issue=Pt 18|pages=3082–95|pmid=21865521|pmc=3160820|year=2011|last1=Riede|first1=T|last2=Tokuda|first2=I. T.|last3=Farmer|first3=C. G.|doi=10.1242/jeb.051110|bibcode=2011JExpB.214.3082R |url=http://epubs.utah.edu/index.php/open/article/download/775/580}}</ref> Their vocal folds consists of epithelium, [[lamina propria]] and muscle. Sounds ranged from 50 to 1200&nbsp;Hz. In one experiment conducted on the larynx, the fundamental frequency depended on both the glottal gap and stiffness of the larynx tissues. As the frequency increases, there's high tension and large strains. The fundamental frequency has been influenced by the glottal gap size and subglottal pressure and when the phonation threshold pressure has been exceeded, there will be vocal fold vibration.<ref name="American Alligator Vocal">{{cite journal |last1=Riede |first1=T |last2=Li |first2=Z |last3=Tokuda |first3=I |last4=Farmer |first4=C |title=Functional morphology of the ''Alligator mississippiensis'' larynx with implications for vocal production |journal=Journal of Experimental Biology |date=2015 |volume=218 |issue=7 |pages=991–998 |doi=10.1242/jeb.117101|pmid=25657203 |doi-access=free |bibcode=2015JExpB.218..991R }}</ref>

====Calls====
[[Crocodilia]]ns are the most vocal of all non-avian reptiles and have a variety of different calls depending on the age, size, and sex of the animal.<ref>{{cite web|last=Britton|first=Adam|title=Crocodile Talk|url=http://crocodilian.com/cnhc/croccomm.html|publisher=University of Bristol and Florida Museum of Natural History |website=Crocodilians |archive-url=https://web.archive.org/web/20221026132628/http://crocodilian.com/cnhc/croccomm.html |archive-date= Oct 26, 2022 }}</ref> The American alligator can perform specific vocalizations to declare territory, signal distress, threaten competitors, and locate suitable mates. Juveniles can perform a high-pitched hatchling call (a "yelping" trait common to many crocodilian species' hatchling young)<ref>{{cite web |url=https://www.youtube.com/watch?v=ZjqajHt6CAU |title=Hatchling American Alligators Calling |website=YouTube |date=September 3, 2013 |access-date=2016-09-07 |first1=David |last1=Barkasy }}</ref> to alert their mothers when they are ready to emerge from the nest. Juveniles also make a distress call to alert their mothers if they are being threatened. Adult American alligators can growl, hiss, or cough to threaten others and declare territory.

====Bellowing====
Both males and females bellow loudly by sucking air into their lungs and blowing it out in intermittent, deep-toned roars that likely serve to advertise their presence.<ref name="Reber 2018">{{cite encyclopedia|last1=Reber |first1=Stephan A. |title=Crocodilia Communication |encyclopedia=Encyclopedia of Animal Cognition and Behavior |date=2018 |pages=1–10 |doi=10.1007/978-3-319-47829-6_950-1 |isbn=978-3-319-47829-6 }}</ref><ref name="Jensen et al. 2024">{{cite journal |last1=Jensen |first1=Thomas Rejsenhus |last2=Anikin |first2=Andrey |last3=Osvath |first3=Mathias |last4=Reber |first4=Stephan A. |title=Knowing a fellow by their bellow: acoustic individuality in the bellows of the American alligator |journal=Animal Behaviour |date=2024 |volume=207 |pages=157–167 |doi=10.1016/j.anbehav.2023.11.009|bibcode=2024AnBeh.207..157J |doi-access=free }}</ref> Males are known to use [[infrasound]] during mating bellows.<ref name="Jensen et al. 2024"/> Their bellowing initiates the beginning of the courtship period for American alligators.<ref>{{Cite journal |last1=JOANEN |first1=TED |last2=MCNEASE |first2=LARRY L. |date=August 1989 |title=Ecology and Physiology of Nesting and Early Development of the American Alligator |journal=American Zoologist |volume=29 |issue=3 |pages=987–998 |doi=10.1093/icb/29.3.987 |issn=0003-1569}}</ref> Bellowing is performed in a "head oblique, tail arched" posture. Infrasonic waves from a bellowing male can cause the surface of the water directly over and to either side of his back to literally "sprinkle",<ref>[https://www.youtube.com/watch?v=ZIxl10Qvgw8 Male alligator "sprinkling" while bellowing in near-infrasound during courtship]. YouTube.com (April 28, 2010). Retrieved on 2016-09-07.</ref> in what is commonly called the "water dance".<ref name="Reber 2018"/><ref>{{cite journal |last1=Garrick |first1=L. D. |last2=Lang |first2=J. W. |year=1977 |title=Social Displays of the American Alligator |volume=17 |journal=American Zoologist |pages=225–239 | doi = 10.1093/icb/17.1.225 |doi-access=free }}</ref> Large bellowing "choruses" of American alligators during the breeding season are commonly initiated by females and perpetuated by males.<ref>{{cite journal |last1=Garrick |first1=L. |last2=Lang |first2=J. |last3=Herzog |first3=H. |journal= American Zoologist |title=Social Signals of Adult American Alligators|year=1978|volume=60|issue=3|pages=153–192}}</ref> Observers of large bellowing choruses have noted they are often felt more than they are heard due to the intense infrasound emitted by males. American alligators bellow in B flat (specifically [[Scientific pitch notation#Table of note frequencies|"B♭<sub>1</sub>"]], defined as an audio frequency of 58.27&nbsp;Hz), and bellowing choruses can be induced by tuba players, sonic booms, and large aircraft.<ref>{{cite news|last=Kilnkenberg|first=Jeff|title=Alligators in B Flat? Gatorland's denizens roar in ecstasy|url=https://www.tampabay.com/features/humaninterest/alligators-in-b-flat-gatorlands-denizens-roar-in-ecstasy/2127882/|newspaper=Tampa Bay Times|date=June 21, 2013 |quote="We want to hit the B flat two octaves below middle C, " Mickelsen reminded his young assistant. "At 57 hertz. That's what that old scientific report advised...BLAAAA!...Though only a few clouds scudded across the sky, we heard what sounded like thunder in the distance. It was a randy male American alligator, turned on by tuba, telling the world that he was a stud...He lifted his upper body out of the water while lowering the middle and raising his tail. Though he barely moved, a droplet spray exploded from the water covering his back. "The water dance!" Tim Williams cried. Toxic let loose a roar that shook the earth.}}</ref>

===Lifespan===
American alligators typically live to the age of 50, and possibly over 70 years old. Males reach sexual maturity at around 11.6 years, and females at around 15.8 years. Although it was originally thought that American alligators never stop growing, studies have now found that males stop growing at around the age of 43 years, and females stop growing at around the age of 31 years.<ref name="Wilkinson2016"/>

===Reproduction===
[[File:Crocnest.JPG|thumb|right|An adult American alligator at its nest accompanied by juveniles of various sizes]]
[[File:Alligator mississippiensis baby.jpg|thumb|Young American alligator swimming, showing the distinctive yellow striping found on juveniles]]
[[File:Alligator mississippiensis 113744549.jpg|thumb|right|Juvenile resting on adult]]

====Breeding season====
The [[Reproduction|breeding]] season begins in the spring. On spring nights, American alligators gather in large numbers for group courtship, in the aforementioned "water dances".<ref>{{cite journal |last=Dinets |first=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> A study conducted in the 1980s at an alligator farm showed that homosexual courtship is common, with two-thirds of the recorded instances of sexual behaviour having been between two males.<ref>{{cite journal |last=Vilet |first=Kent A. |year=2000 |title=Courtship behaviour of American Alligators (''Alligator mississippiensis'') |url=https://www.alligatorfarm.com/images/Research/Courtship%20Behavior%20of%20American%20Alligators.pdf |journal=Crocodile Biology and Evolution |pages=383–408}}</ref> Multiple paternity is thought to occur.<ref>{{Cite journal |last1=Davis |first1=Lisa M. |last2=Glenn |first2=Travis C. |last3=Elsey |first3=Ruth M. |last4=Dessauer |first4=Herbert C. |last5=Sawyer |first5=Roger H. |date=2001 |title=Multiple paternity and mating patterns in the American alligator, Alligator mississippiensis |url=https://onlinelibrary.wiley.com/doi/10.1046/j.1365-294X.2001.01241.x |journal=Molecular Ecology |language=en |volume=10 |issue=4 |pages=1011–1024 |doi=10.1046/j.1365-294X.2001.01241.x |pmid=11348507 |bibcode=2001MolEc..10.1011D |issn=1365-294X|url-access=subscription }}</ref> The female builds a nest of vegetation, sticks, leaves, and mud in a sheltered spot in or near the water.

====Eggs====
After the female lays her 20 to 50 white eggs, about the size of a goose egg, she covers them with more vegetation, which heats as it decays, helping to keep the eggs warm. This differs from Nile crocodiles, which lay their eggs in pits.<ref name="Guggisberg" /> The temperature at which American alligator eggs develop determines their sex (see [[temperature-dependent sex determination]]). Studies have found that eggs hatched at a temperature below {{Convert|88.7|F}} or a temperature above {{Convert|94.1|F}} will produce female offspring, while those at a temperature between {{Convert|90.5 and 92.3|F}} will produce male offspring.<ref>{{Cite journal |last1=Bock |first1=Samantha L. |last2=Lowers |first2=Russell H. |last3=Rainwater |first3=Thomas R. |last4=Stolen |first4=Eric |last5=Drake |first5=John M. |last6=Wilkinson |first6=Philip M. |last7=Weiss |first7=Stephanie |last8=Back |first8=Brenton |last9=Guillette |first9=Louis |last10=Parrott |first10=Benjamin B. |date=2020-05-13 |title=Spatial and temporal variation in nest temperatures forecasts sex ratio skews in a crocodilian with environmental sex determination |journal=Proceedings of the Royal Society B: Biological Sciences |volume=287 |issue=1926 |article-number=20200210 |doi=10.1098/rspb.2020.0210|pmid=32345164 |pmc=7282913 }}</ref> The nests built on [[levee]]s are warmer, thus produce males, while the cooler nests of wet marsh produce females.<ref>{{cite journal |last1=Joanen |first1=T. |last2=Ferguson |first2=M. W. J. |year=1982 |title=Temperature of egg incubation determines sex in ''Alligator mississippiensis'' |journal=Nature |volume=296 |pages=850–53 |doi=10.1038/296850a0 |pmid=7070524 |issue=5860|bibcode=1982Natur.296..850F |s2cid=4307265 }}</ref> The female remains near the nest throughout the 65-day [[egg incubation|incubation]] period, protecting it from intruders. When the young begin to hatch — their "yelping" calls can sometimes even be heard just before hatching commences — the mother quickly digs them out and carries them to the water in her mouth,<ref name = "ufl"/> as some other crocodilian species are known to do.

====Young====
The young are tiny replicas of adults, with a series of yellow bands around their bodies that serve as camouflage.<ref name = "ufl"/> Hatchlings gather into pods and are guarded by their mother and keep in contact with her through their "yelping" vocalizations. Young American alligators eat small fish, frogs, crayfish, and insects.<ref name=maternal>{{cite journal|author1=Hunt, R. H. |author2=Watanabe, M. E. |year=1982|title=Observations on the maternal behavior of the American alligator, ''Alligator mississippiensis''|journal=Journal of Herpetology|volume=16|issue=3|pages=235–39|jstor=1563716|doi=10.2307/1563716 |bibcode=1982JHerp..16..235H }}</ref> They are preyed on by large fish, birds, raccoons, Florida panthers, and adult American alligators.<ref name = "ufl"/> Mother American alligators eventually become more aggressive towards their young, which encourages them to disperse.<ref name=maternal/> Young American alligators grow {{convert|3|–|8|in|cm|abbr=on}} a year and reach adulthood at {{convert|6|ft|m|abbr=on}}.<ref name=srel/>

===Parasites===
American alligators are commonly infected with parasites. In a 2016 Texas study, 100% of the specimens collected were infected with parasites, and by at least 20 different species of parasites, including lung [[pentastomid]]s, [[gastric]] [[nematode]]s, and intestinal [[helminths]]. When compared to American alligators from different states there was no significant difference in prevalence.<ref name="par">{{cite journal |last1=Sung |first1=Helen |last2=Tellez |first2=Marisa |title=Spatial variation of parasite infracommunities in the American alligator (''Alligator mississippiensis'') |journal=The Southwestern Naturalist |date=December 2016 |volume=61 |issue=4 |pages=324–328 |doi=10.1894/0038-4909-61.4.324 |bibcode=2016SWNat..61..324S |s2cid=90639824 |url=https://www.researchgate.net/publication/315917666}}</ref>

===Interactions with exotic species===
[[Nutria]] were introduced into coastal marshes from South America in the mid-20th century, and their population has since exploded into the millions. They cause serious damage to coastal marshes and may dig burrows in levees. Hence, Louisiana has had a bounty to try to reduce nutria numbers. Large American alligators feed heavily on nutria, so American alligators may not only control nutria populations in Louisiana, but also prevent them spreading east into the Everglades. Since hunting and trapping preferentially take the large American alligators that are the most important in eating nutria, some changes in harvesting may be needed to capitalize on their ability to control nutria.<ref name=r1/>

Recently, a population of [[Burmese pythons in Florida|Burmese pythons became established]] in Everglades National Park. Substantial American alligator populations in the Everglades might be a contributing factor, as [[competition (biology)#Interspecific competition|a competitor]], in keeping the python populations low, preventing the spread of the species north. While events of [[predation]] by Burmese pythons on sizable American alligators have been observed,<ref name=PMC3289325/><ref>[https://www.nbcnews.com/id/wbna9600151 Gator-guzzling python comes to messy end]. [[Associated Press]] (October 5, 2005). Retrieved 2008-03-11.</ref><ref>Butler, Rhett A. (October 5, 2005) [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> no evidence of a net negative effect has been seen on overall American alligator populations.<ref name="USGS">[[United States Department of the Interior]], [[U.S. Geological Survey]] (February 20, 2008). [https://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>

In Florida, American alligators may be eaten by some growth stage of other invasive snakes such as [[reticulated python]]s, [[Southern African rock python]]s, [[Central African rock python]]s, [[boa constrictor]]s, [[yellow anaconda]]s, [[Bolivian anaconda]]s, [[dark-spotted anaconda]]s, and [[green anaconda]]s.<ref>{{Cite book|title=Final Environmental Assessment For The Large Constrictor Snakes Listed As Injurious Wildlife under the Lacey Act|date=January 2012|publisher=U.S. Fish and Wildlife Service}}</ref>

Young American alligators have been documented consuming a large number of invasive Apple Snails in Northcentral Florida. This trend may be visible across other areas where the range of both species intersects.<ref>{{Cite journal |last1=Delany |first1=Michael F. |last2=Abercrombie |first2=C. L. |date=1986 |title=American Alligator Food Habits in Northcentral Florida |journal=The Journal of Wildlife Management |volume=50 |issue=2 |pages=348–353 |doi=10.2307/3801926 |jstor=3801926 |bibcode=1986JWMan..50..348D |issn=0022-541X}}</ref>

===Indicators of environmental restoration===
[[File:Avery Island, Louisiana-044.JPG|thumb|American alligator at [[Avery Island, Louisiana]]]]
American alligators play an important role in the [[restoration of the Everglades]] as [[biological indicator]]s of restoration success.<ref>{{cite web |title=The American Alligator: An Indicator Species for Everglades Restoration |url=http://edis.ifas.ufl.edu/pdffiles/UW/UW35800.pdf |publisher=University of Florida IFAS Extension |last1=Harvey |first1=Rebecca G. |last2=Brandt |first2=Laura A. |last3=Mazzotti |first3=Frank J. |date=October 2011}}</ref> American alligators are highly sensitive to changes in the hydrology, salinity, and productivity of their ecosystems; all are factors that are expected to change with Everglades restoration. American alligators also may control the long-term vegetation dynamics in wetlands by reducing the population of small mammals, particularly nutria, which may otherwise overgraze marsh vegetation.<ref name=r1>Keddy, P.A., L. Gough, J.A. Nyman, T. McFalls, J. Carter and J. Siegrist (2009). [http://www.drpaulkeddy.com/pdffiles/Keddy_et_al_2009_alligator_trophic_cascade.pdf Alligator hunters, pelt traders, and runaway consumption of Gulf coast marshes: A trophic cascade perspective on coastal wetland losses.] {{Webarchive|url=https://web.archive.org/web/20141103232924/http://www.drpaulkeddy.com/pdffiles/Keddy_et_al_2009_alligator_trophic_cascade.pdf |date=November 3, 2014 }} pp. 115–133 in B.R. Silliman, E.D. Grosholz, and M.D. Bertness (eds.) ''Human Impacts on Salt Marshes. A Global Perspective''. University of California Press, Berkeley, CA {{ISBN|0-520-25892-4}} [https://books.google.com/books?id=dZbvgaYT6JYC&pg=PA115 Google Books]</ref>  In this way, the vital ecological service they provide may be important in reducing rates of coastal [[wetland]] losses in Louisiana.<ref>Keddy, P.A. (2010). ''Wetland Ecology: Principles and Conservation'' (2nd edition). Cambridge University Press, Cambridge, UK. {{ISBN|0-521-78367-4}}.</ref> They may provide a protection service for water birds nesting on islands in freshwater wetlands. American alligators prevent predatory mammals from reaching island-based [[rookery|rookeries]] and in return eat spilled food and birds that fall from their nests. Wading birds appear to be attracted to areas with American alligators and have been known to nest at heavily trafficked tourist attractions with large numbers of American alligators, such as the [[St. Augustine Alligator Farm Zoological Park|St. Augustine Alligator Farm]] in St. Augustine, Florida.<ref>{{cite web |last1=White |first1=C. |last2=Frederick |first2=P. |last3=Main |first3=M. |last4=Rodgers |first4=J. |title=Nesting Island Creation for Wading Birds |date=May 2005 |url=http://edis.ifas.ufl.edu/pdffiles/UW/UW22300.pdf |publisher=University of Florida IFAS Extension}}</ref>

== Relationship with humans ==
[[File:American alligator swimming.jpg|thumb|An American alligator swimming in an enclosure at a zoo]]

===Attacks on humans===
[[File:Alligator mississippiensis defensive.jpg|thumb|right|Defensive American alligator with mouth open]]
{{main|List of fatal alligator attacks in the United States}}

American alligators are capable of killing humans, but fatal attacks are rare. Mistaken identity leading to an attack is always possible, especially in or near cloudy waters. American alligators are often less aggressive towards humans than larger crocodile species, a few of which (mainly the Nile and saltwater crocodiles) may prey on humans with some regularity.<ref name="Wood"/><ref>[http://www.sciencekids.co.nz/sciencefacts/animals/crocodilealligatordifferences.html Crocodile and Alligator Differences – Animal Facts for Kids]. Sciencekids.co.nz (July 11, 2012). Retrieved on 2012-08-21.</ref> Alligator bites are serious injuries, due to the reptile's sheer bite force and risk of infection. Even with medical treatment, an American alligator bite may still result in a fatal infection.<ref>{{cite journal |last1=Harding |first1=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 |pmid=16696720 |s2cid=39551914 }}</ref>

As human populations increase, and as they build houses in low-lying areas, or fish or hunt near water, incidents are inevitable where humans intrude on American alligators and their habitats. Since 1948, 257 documented attacks on humans in Florida (about five incidents per year) have been reported, of which an estimated 23 resulted in death.<ref>McLaughlin, Eliott C.; Almasy, Steve and Shoichet, Catherine E. (2016-06-16) [http://www.cnn.com/2016/06/16/us/alligator-attacks-child-disney-florida/index.html Disney alligator attack: Resort to add warning signs, source says]. ''CNN''<!-- [https://web.archive.org/web/20071016203825/http://myfwc.com/gators/faq/lwa.htm Living with Alligators], Myfwc.com. --></ref> Only nine fatal attacks occurred in the United States throughout the 1970s–1990s, but American alligators killed 12 people between 2001 and 2007. An additional report of alligator attacks showed a total of 376 injuries and 15 deaths recorded all from 1948 to 2004, leading this to an increase of the alligator population.<ref>{{Cite journal |last=Langley |first=Ricky |date=September 1, 2005 |title=Alligator Attacks on Humans |journal=Wilderness & Environmental Medicine|volume=16 |issue=3 |pages=119–124 |doi=10.1580/1080-6032(2005)16[119:AAOHIT]2.0.CO;2 |pmid=16209465 |s2cid=37639089 |doi-access=free }}</ref> In May 2006, American alligators killed three Floridians in less than a week.<ref>{{cite news|url=https://www.nytimes.com/2006/05/15/us/15alligator.html |title=A String of Deaths by Gators in Florida |newspaper=nytimes.com |date=May 15, 2006 |access-date=May 15, 2006}}</ref> At least 28 fatal attacks by American alligators have occurred in the United States since 1970.

=== Wrestling ===
{{main|Alligator wrestling}}

[[File:GilletteAlligatorWrestling.jpg|thumb|Man wrestling American alligator]]
Since the late 1880s, alligator wrestling has been a source of entertainment for some. Created by the [[Miccosukee]] and [[Seminole]] tribes for food prior to its popularity for tourism, this tourism tradition remains popular despite criticism from animal-rights activists.<ref>{{cite news|title=Alligator wrestling – cruelty or tradition?|publisher=BBC News.com|date=March 17, 2009|url=https://news.bbc.co.uk/2/hi/americas/7941699.stm|access-date=August 29, 2012}}</ref>

===Farming===
{{main|Alligator farm}}

[[File:FMIB 33999 Alligator Skins edited.png|thumb|American alligator skins]]
Alligator farming is a large, 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|–|7|ft|m}} range have sold for $300 each.<ref>{{cite web|author1=Lane, Thomas J. |author2=Ruppert, Kathleen C. |date=June 2008|title=Alternative Opportunities for Small Farms:Alligator Production Review|publisher=University of Florida|access-date=August 29, 2012|url=http://myfwc.com/media/310209/Alligator_IFASrfac002.pdf}}</ref> The market for [[alligator meat]] is growing, and about {{Convert|300000|lb|kg}} of meat are produced annually.<ref>{{cite web|author=Reig Eimeric|year=2006|title=Gator Maters: Florida farmers find lucrative business mating alligators|publisher=Orange and Blue Magazine|access-date=August 29, 2012|url=http://www.jou.ufl.edu/pubs/onb/F06/index.php?id=9|archive-url=https://web.archive.org/web/20130530231721/http://www.jou.ufl.edu/pubs/onb/F06/index.php?id=9|archive-date=May 30, 2013}}</ref> According to the [[Florida Department of Agriculture and Consumer Services]], raw alligator meat contains {{convert|232|cal|kJ}} per {{convert|3.2|oz|g}} portion, of which {{convert|38|cal|kJ}} come from fat.<ref>{{cite web|url=https://www.fdacs.gov/Consumer-Resources/Buy-Fresh-From-Florida/Florida-Alligator-Meat-Skins-and-Hides|title=Florida Alligator Meat, Skins and Hides|website=[[Florida Department of Agriculture and Consumer Services]]|access-date=April 17, 2025}}</ref>
[[File:American alligator on grass.jpg|thumb|An American alligator sunning itself on the grass at a zoo]]

==Culture==
The American alligator is the official [[state reptile]] of Florida,<ref name="fl">{{cite web | url=http://www.flheritage.com/kids/symbol.cfm?id=3 | title=Alligator | publisher=Florida Division of Historical Resources | work=Florida State Symbols | year=2013 | access-date=April 6, 2013}}</ref> Louisiana,<ref name="la">{{cite web | url=http://louisiana.gov/Explore/About_Louisiana/ | title=About Louisiana | publisher=State of Louisiana | work=Louisiana.gov | access-date=April 6, 2013 | archive-url=https://web.archive.org/web/20130324052614/http://louisiana.gov/Explore/About_Louisiana/ | archive-date=March 24, 2013 }}</ref> and Mississippi.<ref name="ms">{{cite act |title=An Act To Designate The American Alligator As The State Reptile; And For Related Purposes |institution=Mississippi Legislature |number=2060 |date=July 1, 2005 |url=http://billstatus.ls.state.ms.us/documents/2005/pdf/SB/2001-2099/SB2060SG.pdf|access-date=April 6, 2013}}</ref>

[[Florida Gators|"Gators"]] has been the nickname of the [[University of Florida]]'s sports teams since 1911. In 1908, a printer made a spur-of-the-moment decision to print an alligator emblem on a shipment of the school's football pennants.<ref>{{cite web|title=History of the Gator|url=http://floridagators.com/sports/2015/12/10/_spirit_mascots_history_.aspx|website=Official website of Gator Athletics|publisher=University of Florida|access-date=17 October 2017}}</ref> The mascot stuck, and was made official in 1911, 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 |access-date=February 13, 2011 |publisher=University of Florida |archive-url=https://web.archive.org/web/20101231184043/http://www.ufl.edu/history/1906.html |archive-date=December 31, 2010 }}</ref> [[Allegheny College]] and [[San Francisco State University]] both have Gators as their mascots, as well.<ref>{{cite web |url=https://alleghenygators.com/sports/2017/4/13/why-gators.aspx |title=Why Gators? |access-date=March 30, 2019 |publisher=Allegheny College}}</ref>

The [[Gator Bowl]] is a [[college football]] game held in [[Jacksonville]] annually since 1946, with [[Gator Bowl Stadium]] hosting the event until the 1993 edition. The [[Gatornationals]] is a [[NHRA]] drag race held at the [[Gainesville Raceway]] in Gainesville since 1970.

==See also==
* [[Chinese alligator]], the other living species of alligator
* [[Muja (alligator)|Muja]], the oldest living American alligator in captivity, lived in [[Belgrade Zoo]], [[Serbia]]
* [[Saturn (alligator)|Saturn]], an American alligator that survived the destruction of the [[Berlin Zoological Garden]] during [[World War II]]
* ''[[The Alligator People]]''
* [[Gatorland]]
* [[Brazos Bend State Park]]
* [[Sewer alligator]]
* [[American Crocodile]]

==References==
{{Reflist|30em}}

==Further reading==
* [[George Albert Boulenger|Boulenger GA]] (1889). ''Catalogue of the Chelonians, Rhynchocephalians, and Crocodiles in the British Museum (Natural History). New Edition.'' London: Trustees of the British Museum (Natural History). (Taylor and Francis, printers). x + 311 pp. + Plates I-VI. (''Alligator mississippiensis'', p.&nbsp;290).
* [[François Marie Daudin|Daudin FM]] (1802). ''Histoire Naturelle, Générale et Particulière des Reptiles; Ouvrage faisant suite à l'Histoire Naturelle générale et particulière, composée par [[Georges-Louis Leclerc, Comte de Buffon|Leclerc de Buffon]]; et rédigée par [[Charles-Nicolas-Sigisbert Sonnini de Manoncourt|C.S. Sonnini]], membre de plusieurs sociétés savantes. Tome Second'' [Volume 2]. 432 pp. Paris: F. Dufart. ("''Crocodilus mississipiensis'' [sic]", new species, pp.&nbsp;412–416). (in French and Latin).
* [[Robert Powell (herpetologist)|Powell R]], [[Roger Conant (herpetologist)|Conant R]], [[Joseph T. Collins|Collins JT]] (2016). ''Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition''. Boston and New York: Houghton Mifflin Harcourt. xiv + 494 pp., 47 Plates, 207 Figures. {{ISBN|978-0-544-12997-9}}. (''Alligator mississippiensis'', p.&nbsp;170 + Plate 13 + photographs on pp.&nbsp;166–167, 465).
* [[Hobart Muir Smith|Smith, Hobart M.]]; Brodie, Edmund D., Jr. (1982). ''Reptiles of North America: A Guide to Field Identification''. New York: Golden Press. 240 pp. {{ISBN|0-307-13666-3}}. (''Alligator mississippiensis'', pp.&nbsp;208–209).

==External links==
{{Commons and category|Alligator mississippiensis|Alligator mississippiensis}}
{{Wikispecies|Alligator mississippiensis}}
* [http://www.crocodilian.com Crocodilian Online] {{Webarchive|url=https://web.archive.org/web/20110708204615/http://www.crocodilian.com/ |date=July 8, 2011 }}
* [https://www.floridamemory.com/learn/exhibits/photo_exhibits/alligators/ Photo exhibit on alligators in Florida] from [[State Archives of Florida]]
* [https://web.archive.org/web/20130827222507/http://drpaulkeddy.com/talks_--_alligators_and_nutria.html Why the Gulf Coast needs more big alligators]
* [http://www.fws.gov/video/sound.htm Alligator bellows and hisses] {{Webarchive|url=https://web.archive.org/web/20140301031934/http://www.fws.gov/video/sound.htm |date=March 1, 2014 }} – sound clips from the [[U.S. Fish and Wildlife Service]]
* {{UCSC genomes|allMis1}}

{{Crocodilia|A.}}
{{Crocs}}

{{Taxonbar|from=Q193327}}
{{Authority control}}

{{DEFAULTSORT:Alligator, American}}
[[Category:Alligator]]
[[Category:Crocodilians of North America]]
[[Category:Reptiles of the United States]]
[[Category:Reptiles of Mexico]]
[[Category:Miocene reptiles of North America]]
[[Category:Extant Tortonian first appearances]]
[[Category:Fauna of the Southeastern United States]]
[[Category:Cuisine of the Southern United States]]
[[Category:Native American cuisine of the Southeastern Woodlands]]
[[Category:Apex predators]]
[[Category:Articles containing video clips]]
[[Category:Symbols of Florida]]
[[Category:Symbols of Louisiana]]
[[Category:Symbols of Mississippi]]
[[Category:Tool-using animals]]
[[Category:Natural history of Florida]]
[[Category:Reptiles described in 1802]]
[[Category:Taxa named by François Marie Daudin]]
[[Category:Least concern biota of the United States]]