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{{Short description|Species of bird}}
{{Short description|Species of bird}}
{{For|the bird genus ''Anhinga''|Darter}}
{{For|the bird genus Anhinga|darter}}
{{Speciesbox
{{Speciesbox
| italic_title = no
| italic_title = no
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| image = Anhinga anhinga -Costa Rica-8.jpg
| image = Anhinga anhinga -Costa Rica-8.jpg
| image_caption = Male in Costa Rica
| image_caption = Male in Costa Rica
| image2 = Female anhinga in Florida.jpg
| image2 = AnhingaFemale.jpg
| image2_caption = Female in Florida
| image2_caption = Female in [[Tampa, Florida]]
| status = LC
| status = LC
| status_system = IUCN3.1
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 13 November 2021">{{cite iucn |author=BirdLife International |date=2016 |title=''Anhinga anhinga'' |volume=2016 |page=e.T22696702A93581588 |doi=10.2305/IUCN.UK.2016-3.RLTS.T22696702A93581588.en |access-date=13 November 2021}}</ref>
| status_ref = <ref name="iucn">{{cite iucn |author=BirdLife International. |year=2025 |title=''Anhinga anhinga'' |volume=2025 |article-number=e.T22696702A281836797 |doi=10.2305/IUCN.UK.2025-2.RLTS.T22696702A281836797.en |access-date=22 November 2025}}</ref>
| status2 = G5
| status2 = G5
| status2_system = TNC
| status2_system = TNC
| status2_ref = <ref>{{cite web|title=Anhinga anhinga|url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.100210/Anhinga_anhinga|website=[[NatureServe]] Explorer|access-date=17 April 2024}}</ref>
| status2_ref = <ref>{{cite web|title=''Anhinga anhinga''|url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.100210/Anhinga_anhinga|work=[[NatureServe]] Explorer |publisher=[[The Nature Conservancy]]|access-date=17 April 2024}}</ref>
| genus = Anhinga
| genus = Anhinga
| species = anhinga
| species = anhinga
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| synonyms = ''Plotus anhinga'' {{small|Linnaeus,&nbsp;1766}}
| synonyms = ''Plotus anhinga'' {{small|Linnaeus,&nbsp;1766}}
}}
}}
The '''anhinga''' ({{IPAc-en|æ|n|ˈ|h|ɪ|ŋ|g|ə}}; '''''Anhinga anhinga'''''), sometimes called '''snakebird''', '''darter''', '''American darter''', or '''water turkey''', is a water bird of the warmer parts of the Americas. The word ''anhinga'' comes from ''a'ñinga'' in the Brazilian [[Tupi language]] and means "devil bird" or "snake bird".<ref>Ferreira, A. B. H. (1986). ''Novo Dicionário da Língua Portuguesa''. Second edition. Rio de Janeiro: Nova Fronteira. p. 123.</ref> The origin of the name is apparent when swimming: only the neck appears above water, so the bird looks like a snake ready to strike. They do not have external nares (nostrils) and breathe solely through their [[epiglottis]].
The '''anhinga''' ({{IPAc-en|æ|n|ˈ|h|ɪ|ŋ|g|ə}}; '''''Anhinga anhinga'''''), sometimes called '''snakebird''', '''darter''', '''American darter''', or '''water turkey''', is a water bird of the warmer parts of the Americas. The word ''anhinga'' comes from ''a'ñinga'' in the Brazilian [[Tupi language]] and means "devil bird" or "snake bird".<ref>{{cite book|author=Ferreira, A. B. H. |year=1986|title=Novo Dicionário da Língua Portuguesa|edition= Second|location= Rio de Janeiro|publisher= Nova Fronteira|page= 123}}</ref> The origin of the name is apparent when swimming: only the neck appears above water, so the bird looks like a snake ready to strike. They do not have external nares (nostrils) and breathe solely through their [[epiglottis]].{{citation needed|date=August 2025}}


The anhinga is placed in the darter family, [[Anhingidae]], and is closely related to [[Indian darter|Indian]] (''Anhinga melanogaster''), [[African darter|African]] (''Anhinga rufa''), and [[Australian darter|Australian]] (''Anhinga novaehollandiae'') [[darter]]s. Like other darters, the anhinga hunts by spearing fish and other small prey using its sharp, slender beak.
The anhinga is placed in the darter family, [[Anhingidae]], and is closely related to [[Indian darter|Indian]] (''Anhinga melanogaster''), [[African darter|African]] (''Anhinga rufa''), and [[Australian darter|Australian]] (''Anhinga novaehollandiae'') [[darter]]s. Like other darters, the anhinga hunts by spearing fish and other small prey using its sharp, slender beak.


==Distribution and migration==
==Distribution and migration==
Members of the ''[[Darter|Anhinga]]'' genus live in warm, shallow waters and swamplands worldwide.<ref name=Nellis/> The American anhinga has been subdivided into two subspecies, ''A. a. anhinga'' and ''A. a. leucogaster'', based on their respective location. ''A. a. anhinga'' can be found mainly east of the [[Andes]] in [[South America]], east to the islands of [[Trinidad and Tobago]]. ''A. a. leucogaster'' can be found in the [[southern United States]], [[Mexico]], [[Cuba]], and the [[Caribbean]] island of  [[Grenada]].<ref name=Blake/> A fossil species, ''[[Anhinga walterbolesi]],'' has been described from the [[Chattian|Late Oligocene]] to [[Early Miocene]] of [[Australia]].
Members of the ''[[Darter|Anhinga]]'' genus live in warm, shallow waters and swamplands worldwide.<ref name=Nellis/> The American anhinga has been subdivided into two subspecies, ''A. a. anhinga'' and ''A. a. leucogaster'', based on their respective location. ''A. a. anhinga'' can be found mainly east of the [[Andes]] in [[South America]], east to the islands of [[Trinidad and Tobago]]. ''A. a. leucogaster'' can be found in the [[southern United States]], [[Mexico]], [[Cuba]], and the [[Caribbean]] island of  [[Grenada]].<ref name=Blake/> A fossil species, ''[[Anhinga walterbolesi]]'', has been described from the [[Chattian|Late Oligocene]] to [[Early Miocene]] of [[Australia]].


Only birds living in the extreme north or south of their respective ranges will [[Bird migration|migrate]] based on temperature and available sunlight; anhingas will travel closer towards the [[equator]] during winter, but this range is "determined by the amount of sunshine to warm the chilled birds".<ref name=Nellis/> Although not part of their traditional range, American anhingas have been found as far north as the states of [[Pennsylvania]],<ref name=McWilliams/> [[Wisconsin]],<ref name=Robbins/> and [[New York (state)|New York.]]<ref>{{Citation| title = The 'Devil Bird' Lands in New York, With More Likely to Come | newspaper = [[The New York Times]]| date = 4 May 2023}}</ref>
Only birds living in the extreme north or south of their respective ranges will [[Bird migration|migrate]] based on temperature and available sunlight; anhingas will travel closer towards the [[equator]] during winter, but this range is "determined by the amount of sunshine to warm the chilled birds".<ref name=Nellis/> Although not part of their traditional range, American anhingas have been found as far north as the states of [[Pennsylvania]],<ref name=McWilliams/> [[Wisconsin]],<ref name=Robbins/> and [[New York (state)|New York.]]<ref>{{Cite news| title = The 'Devil Bird' Lands in New York, With More Likely to Come | newspaper = [[The New York Times]]| date = 4 May 2023}}</ref>


[[Kettle (birds)|Kettles]] of anhingas often migrate with other species of birds, and have been described as resembling "black paper gliders".<ref name=Eubanks/>
[[Kettle (birds)|Kettles]] of anhingas often migrate with other species of birds, and have been described as resembling "black paper gliders".<ref name=Eubanks/>


==Description==
==Description==
The anhinga is a large bird, measuring approximately {{convert|89|cm|in|abbr=on}} in length (with a range of {{convert|75|-|95|cm|in|abbr=on}}), with a {{convert|1.14|m|ft|abbr=on}} wingspan.<ref name=Sibley/><ref name=Cornell/> The ''A. a. anhinga'' subspecies is larger than ''A. a. leucogaster'' and has broader buffy tail tips.<ref name=Blake/> They weigh on average around {{convert|1.22|kg|lbs|abbr=on}}, with a range of {{convert|1.04|-|1.35|kg|lb|abbr=on}}.<ref name= Cornell/><ref name=Maehr/><ref name=Hennemann1985/> The bill is relatively long (about twice the length of the head), sharply pointed, and yellow, and the webbed feet are yellow as well.<ref name=Robbins/><ref name=Audubon/><ref name=Sibley/><ref name=Maehr/>
The anhinga is a large bird, measuring approximately {{convert|89|cm|in|abbr=on}} in length (with a range of {{cvt|75|-|95|cm|in}}), with a {{cvt|1.14|m|ft}} wingspan.<ref name=Sibley/><ref name=Cornell/> The ''A. a. anhinga'' subspecies is larger than ''A. a. leucogaster'' and has broader buffy tail tips.<ref name=Blake/> They weigh on average around {{cvt|1.22|kg|lb}}, with a range of {{cvt|1.04|-|1.35|kg|lb}}.<ref name= Cornell/><ref name=Maehr/><ref name=Hennemann1985/> The bill is relatively long (about twice the length of the head), sharply pointed, and yellow, and the webbed feet are yellow as well.<ref name=Robbins/><ref name=Audubon/><ref name=Sibley/><ref name=Maehr/>


The male is glossy black-green, including its wings and the base of its wings, while its tail is glossy black-blue.<ref name=Audubon/> The tip of the tail is white.<ref name=Wood/> The back of the head and the neck have elongated feathers that have been described as gray<ref name=Chapman/> or light purple-white.<ref name=Audubon/> The upper back of the body and wings are spotted or streaked with white.<ref name=Chapman/>
The male is glossy black-green, including its wings and the base of its wings, while its tail is glossy black-blue.<ref name=Audubon/> The tip of the tail is white.<ref name=Wood/> The back of the head and the neck have elongated feathers that have been described as gray<ref name=Chapman/> or light purple-white.<ref name=Audubon/> The upper back of the body and wings are spotted or streaked with white.<ref name=Chapman/>
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The hatchling starts bald but gains tan down within a few days of hatching. Within two weeks, the tan down is replaced by white down. Three weeks after hatching, the first juvenile feathers appear. Juveniles are mostly brown until they first breed, usually after the second or third winter.<ref name=Nellis/>
The hatchling starts bald but gains tan down within a few days of hatching. Within two weeks, the tan down is replaced by white down. Three weeks after hatching, the first juvenile feathers appear. Juveniles are mostly brown until they first breed, usually after the second or third winter.<ref name=Nellis/>


Anhinga are similar in size, shape, and behavior to the [[double-crested cormorant]]. The two species can be differentiated by their tails, bills, and flight. The tail of the anhinga is wider and longer, only the bill of the cormorant has a hook-tip, only the anhinga can glide in flight.<ref name=Peterson/>
Anhinga are similar in size, shape, and behavior to the [[double-crested cormorant]]. The two species can be differentiated by their tails, bills, and flight. The tail of the anhinga is wider and longer, only the cormorant's bill has a hook-tip, only the anhinga can glide in flight.<ref name=Peterson/>


Typical of the genus, anhingas have a "kinked” neck due to the of the unique “hinge” morphology of the joint between eighth and ninth cervical vertebrae.<ref>{{Cite journal |last=Garrod |first=A. H. |date=1876 |title=1. Notes on the Anatomy of Plotus anhinga. |url=https://zslpublications.onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.1876.tb02572.x |journal=Proceedings of the Zoological Society of London |language=en |volume=44 |issue=1 |pages=335–345 |doi=10.1111/j.1096-3642.1876.tb02572.x |issn=1469-7998}}</ref>
Typical of the genus, anhingas have a "kinked" neck due to the unique "hinge" morphology of the joint between the eighth and ninth cervical vertebrae.<ref>{{Cite journal |last=Garrod |first=A. H. |date=1876 |title=1. Notes on the Anatomy of ''Plotus anhinga''. |url=https://zslpublications.onlinelibrary.wiley.com/doi/10.1111/j.1096-3642.1876.tb02572.x |journal=Proceedings of the Zoological Society of London |language=en |volume=44 |issue=1 |pages=335–345 |doi=10.1111/j.1096-3642.1876.tb02572.x |issn=1469-7998}}</ref>


==Behavior==
==Behavior==
Anhingas swim underwater by kicking their [[Webbed foot|webbed feet]] to pursue their prey, fish or amphibians, which they spear by rapidly outstretching their bent neck. They come up to the surface to consume and swallow prey.<ref>Frederick, P. C. and D. Siegel-Causey (2000). Anhinga (''Anhinga anhinga''), version 2.0. In The Birds of North America (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA.      Pg 4-5 [[Digital object identifier|DOI]]: [https://birdsna.org/Species-Account/bna/species/anhing/introduction 10.2173/bna.522]</ref> Unlike [[duck]]s, [[osprey]]s and [[pelican]]s, which coat their feathers with oils from the [[uropygial gland]], the anhinga does not have this ability; anhingas lack waterproof feathers on their bodies, causing them to be saturated upon immersion into water, while the flight feathers are slightly less wettable. Thus, their habit of basking in the sun with outstretched wings is crucial. Their dense bones, wetted plumage, and neutral [[buoyancy]] in water allow them to fully submerge and hunt for underwater prey.<ref>{{cite web |url= https://birdsna.org/Species-Account/bna/species/anhing/introduction |title=Anhinga - Introduction |work=Birds of North America Online |via= website: ''birdsna.org'' |language=en |access-date= 2018-12-08 |archive-url= https://web.archive.org/web/20180605100521/https://birdsna.org/Species-Account/bna/species/anhing/introduction|archive-date=2018-06-05 |url-status=live}}</ref><ref>{{Cite journal |last1=Rijke |first1=Arie M. |last2=Jesser |first2=William A. |last3=Mahoney |first3=Sheila A. |date=1989 |title=Plumage wettability of the African darter Anhinga melanogaster compared with the double-crested cormorant Phalacrocorax auritus |url=https://www.tandfonline.com/doi/full/10.1080/00306525.1989.9633739 |journal=Ostrich |language=en |volume=60 |issue=3 |pages=128–132 |doi=10.1080/00306525.1989.9633739 |bibcode=1989Ostri..60..128R |issn=0030-6525|url-access=subscription }}</ref>
Anhingas swim underwater by kicking their [[Webbed foot|webbed feet]] to pursue their prey, fish or amphibians, which they spear by rapidly outstretching their bent neck. They come up to the surface to consume and swallow prey.<ref name=BNA>{{cite book|author=Frederick, P. C. |author2= D. Siegel-Causey |year=2000|chapter= Anhinga (''Anhinga anhinga'')|version=2.0|title= The Birds of North America |editor=A. F. Poole |editor2= F. B. Gill |publisher= Cornell Lab of Ornithology|location= Ithaca, NY, USA|pages= 4–5 |chapter-url=https://birdsna.org/Species-Account/bna/species/anhing/introduction |doi=10.2173/bna.522}}</ref> Unlike [[duck]]s, [[osprey]]s and [[pelican]]s, which coat their feathers with oils from the [[uropygial gland]], the anhinga does not have this ability; anhingas lack waterproof feathers on their bodies, causing them to be saturated upon immersion into water, while the flight feathers are slightly less wettable. Thus, their habit of basking in the sun with outstretched wings is crucial. Their dense bones, wetted plumage, and neutral [[buoyancy]] in water allow them to fully submerge and hunt for underwater prey.<ref name=BNA/><ref>{{Cite journal |last1=Rijke |first1=Arie M. |last2=Jesser |first2=William A. |last3=Mahoney |first3=Sheila A. |date=1989 |title=Plumage wettability of the African darter ''Anhinga melanogaster'' compared with the double-crested cormorant ''Phalacrocorax auritus'' |url=https://www.tandfonline.com/doi/full/10.1080/00306525.1989.9633739 |journal=Ostrich |language=en |volume=60 |issue=3 |pages=128–132 |doi=10.1080/00306525.1989.9633739 |bibcode=1989Ostri..60..128R |issn=0030-6525|url-access=subscription }}</ref>


Anhingas cannot fly for any extended distance with soaked feathers; if they attempt to fly while wet, notable difficulty is experienced, the birds flapping vigorously while "running" on the water's surface for a short distance (often escaping a perceived threat).  Like [[cormorants]], anhingas perch and rest on fallen trees, logs or rocks near the water's edge with wings spread and feathers fanned-open in a semicircular shape, facing away from the sun, in order to dry themselves and absorb the sun's heat.<ref name=":1">Hennemann, Willard W. "[https://sora.unm.edu/sites/default/files/journals/condor/v084n01/p0091-p0096.pdf Energetics and Spread-Winged Behavior of Anhingas in Florida]" ''The Condor''84, no. 1 (1982): 91-96. [[JSTOR]] [https://www.jstor.org/stable/1367827 1367827]</ref>  Anhingas also lose body heat relatively fast, and their posture helps them absorb solar radiation from the sun to counteract this.<ref name=":1" /> Because an anhinga in the drying position resembles a male [[Turkey (bird)|turkey]], it has been colloquially referred to as the 'water turkey' or 'swamp turkey'.{{cn|date=December 2024}}
Anhingas cannot fly for any extended distance with soaked feathers; if they attempt to fly while wet, notable difficulty is experienced, the birds flapping vigorously while "running" on the water's surface for a short distance (often escaping a perceived threat).  Like [[cormorants]], anhingas perch and rest on fallen trees, logs or rocks near the water's edge with wings spread and feathers fanned-open in a semicircular shape, facing away from the sun, in order to dry themselves and absorb the sun's heat.<ref name=":1">{{cite journal |author=Hennemann, Willard W. |url=https://sora.unm.edu/sites/default/files/journals/condor/v084n01/p0091-p0096.pdf |title=Energetics and Spread-Winged Behavior of Anhingas in Florida|journal=The Condor|volume=84 |issue=1 |year=1982|pages= 91–96|doi=10.2307/1367827 |jstor= 1367827}}</ref>  Anhingas also lose body heat relatively fast, and their posture helps them absorb solar radiation from the sun to counteract this.<ref name=":1" /> Because an anhinga in the drying position resembles a male [[Turkey (bird)|turkey]], it has been colloquially referred to as the 'water turkey' or 'swamp turkey'.{{cn|date=December 2024}}


== Diet ==
== Diet ==
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Anhingas feed on moderately sized wetland fishes,<ref name="Cornell" /> amphibians,<ref>{{cite web |url=https://sta.uwi.edu/fst/lifesciences/sites/default/files/lifesciences/images/Anhinga%20anhinga%20-%20Anhinga%20or%20Snake-bird.pdf |title=The Online Guide to the Animals of Trinidad and Tobago - Anhinga anhinga (Anhinga or Snake-bird)}}</ref> aquatic invertebrates and insects.<ref name="animaldiversity.org">{{cite web|last=Kearns |first=Laura |url=https://animaldiversity.org/accounts/Anhinga_anhinga/ |title=ADW: Anhinga anhinga: INFORMATION |publisher=Animaldiversity.org |date= |access-date=2022-08-08}}</ref> In [[Alabama]], the anhinga's diet consists of fishes (such as [[mullet (fish)|mullet]], [[Centrarchidae|sunfish]], [[black bass]], [[catfish]], [[Catostomidae|suckers]], and [[chain pickerel]]), [[crayfish]], [[crab]]s, [[shrimp]], [[aquatic insects]], [[tadpole]]s, [[Nerodia|water snakes]] and small [[terrapins]].<ref>{{Cite book|title=Alabama Birds|last=Imhof|first=Thomas, A|publisher=University of Alabama Press|year=1962|isbn=978-0-8173-1701-0}}</ref> In Florida, [[Centrarchidae|sunfishes and bass]], [[Cyprinodontiformes|killifishes]], and [[Poeciliidae|live-bearing fishes]] are primarily eaten by the anhingas.<ref name=":2">{{Cite journal|url= https://sora.unm.edu/sites/default/files/journals/om/om006.pdf#page=127 |title=Adaptations for locomotion and feeding in the Anhinga and the Double-crested cormorant|last=Owre|first=Oscar, T|journal=Ornithological Monographs |publisher=American Ornithologists Union|year=1967 |issue=6 |doi= 10.2307/40166666 |isbn=978-0-9436-1006-1|pages=126–127|jstor=40166666 }}</ref> Other fish eaten include [[pupfish]] and [[Percidae|percids]].<ref name="animaldiversity.org"/>
Anhingas feed on moderately sized wetland fishes,<ref name="Cornell" /> amphibians,<ref>{{cite web |url=https://sta.uwi.edu/fst/lifesciences/sites/default/files/lifesciences/images/Anhinga%20anhinga%20-%20Anhinga%20or%20Snake-bird.pdf |website=The Online Guide to the Animals of Trinidad and Tobago |title=''Anhinga anhinga'' (Anhinga or Snake-bird)|publisher=[[University of the West Indies|UWI]]}}</ref> aquatic invertebrates and insects.<ref name="animaldiversity.org">{{cite web|last=Kearns |first=Laura |url=https://animaldiversity.org/accounts/Anhinga_anhinga/ |title=ADW: ''Anhinga anhinga'': INFORMATION |publisher=Animaldiversity.org |date= |access-date=2022-08-08}}</ref> In [[Alabama]], the anhinga's diet consists of fishes (such as [[mullet (fish)|mullet]], [[Centrarchidae|sunfish]], [[black bass]], [[catfish]], [[Catostomidae|suckers]], and [[chain pickerel]]), [[crayfish]], [[crab]]s, [[shrimp]], [[aquatic insects]], [[tadpole]]s, [[Nerodia|water snakes]] and small [[terrapins]].<ref>{{Cite book|title=Alabama Birds|last=Imhof|first=Thomas, A|publisher=University of Alabama Press|year=1962|isbn=978-0-8173-1701-0}}</ref> In Florida, [[Centrarchidae|sunfishes and bass]], [[Cyprinodontiformes|killifishes]], and [[Poeciliidae|live-bearing fishes]] are primarily eaten by the anhingas.<ref name=":2">{{Cite journal|url= https://sora.unm.edu/sites/default/files/journals/om/om006.pdf#page=127 |title=Adaptations for locomotion and feeding in the Anhinga and the Double-crested cormorant|last=Owre|first=Oscar, T|journal=Ornithological Monographs |publisher=American Ornithologists Union|year=1967 |issue=6 |doi= 10.2307/40166666 |isbn=978-0-9436-1006-1|pages=126–127|jstor=40166666 }}</ref> Other fish eaten include [[pupfish]] and [[Percidae|percids]].<ref name="animaldiversity.org"/>


Anhingas stalk fish underwater, mainly where there is some vegetation. Once they locate their prey, they partly open their bill and stab the fish swiftly. For larger fish, they use both their jaws; for small fish, they may use only the lower jaw.<ref name="Cornell" /> If the fish is too large to forage, the anhinga stabs it repeatedly and then lets it go.<ref>Wellenstein, Charlie (1986). "[https://sora.unm.edu/sites/default/files/FFN_14-3p74-75.pdf#page=1&zoom=auto,-190,266 Prey Handling by Anhingas]". ''Florida Field Naturalist.'' '''14:''' 74-75- via [https://sora.unm.edu/node/134737 SORA]</ref> Anhingas bring their capture to the surface of the water, toss it backward and engulf it head-first.<ref name=":2" />
Anhingas stalk fish underwater, mainly where there is some vegetation. Once they locate their prey, they partly open their bill and stab the fish swiftly. For larger fish, they use both their jaws; for small fish, they may use only the lower jaw.<ref name="Cornell" /> If the fish is too large to forage, the anhinga stabs it repeatedly and then lets it go.<ref>{{cite journal|author=Wellenstein, Charlie |year=1986 |url=https://digitalcommons.usf.edu/cgi/viewcontent.cgi?article=1450&context=ffn |title=Prey Handling by Anhingas|journal=Florida Field Naturalist|volume=14|issue=3|pages= 74–75| via = SORA}}</ref> Anhingas bring their capture to the surface of the water, toss it backward and engulf it head-first.<ref name=":2" />


==Conservation status==
==Conservation status==
The US protects the anhinga under the [[Migratory Bird Treaty Act of 1918]].<ref name=FWS/> The number of individual anhingas has not been estimated, but they are considered to be of least concern because of the frequency of their occurrence in their {{convert|15000000|km2|sqmi|abbr=on}} global range.<ref name="iucn status 13 November 2021" />
The US protects the anhinga under the [[Migratory Bird Treaty Act of 1918]].<ref name=FWS/> The number of individual anhingas has not been estimated, but they are considered to be of least concern because of the frequency of their occurrence in their {{cvt|15000000|km2|sqmi}} global range.<ref name="iucn" />


<gallery>
<gallery>
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[[Category:Mangrove fauna]]
[[Category:Mangrove fauna]]
[[Category:Birds described in 1766]]
[[Category:Birds described in 1766]]
[[Category:Taxa named by Carl Linnaeus]]
[[Category:Animal taxa named by Carl Linnaeus]]
[[Category:Extant Pleistocene first appearances]]
[[Category:Extant Pleistocene first appearances]]
[[Category:Birds of the United States]]
[[Category:Least concern biota of the United States]]

Latest revision as of 23:49, 3 December 2025

Template:Short description Script error: No such module "For". Template:Speciesbox The anhinga (Template:IPAc-en; Anhinga anhinga), sometimes called snakebird, darter, American darter, or water turkey, is a water bird of the warmer parts of the Americas. The word anhinga comes from a'ñinga in the Brazilian Tupi language and means "devil bird" or "snake bird".[1] The origin of the name is apparent when swimming: only the neck appears above water, so the bird looks like a snake ready to strike. They do not have external nares (nostrils) and breathe solely through their epiglottis.Script error: No such module "Unsubst".

The anhinga is placed in the darter family, Anhingidae, and is closely related to Indian (Anhinga melanogaster), African (Anhinga rufa), and Australian (Anhinga novaehollandiae) darters. Like other darters, the anhinga hunts by spearing fish and other small prey using its sharp, slender beak.

Distribution and migration

Members of the Anhinga genus live in warm, shallow waters and swamplands worldwide.[2] The American anhinga has been subdivided into two subspecies, A. a. anhinga and A. a. leucogaster, based on their respective location. A. a. anhinga can be found mainly east of the Andes in South America, east to the islands of Trinidad and Tobago. A. a. leucogaster can be found in the southern United States, Mexico, Cuba, and the Caribbean island of Grenada.[3] A fossil species, Anhinga walterbolesi, has been described from the Late Oligocene to Early Miocene of Australia.

Only birds living in the extreme north or south of their respective ranges will migrate based on temperature and available sunlight; anhingas will travel closer towards the equator during winter, but this range is "determined by the amount of sunshine to warm the chilled birds".[2] Although not part of their traditional range, American anhingas have been found as far north as the states of Pennsylvania,[4] Wisconsin,[5] and New York.[6]

Kettles of anhingas often migrate with other species of birds, and have been described as resembling "black paper gliders".[7]

Description

The anhinga is a large bird, measuring approximately Script error: No such module "convert". in length (with a range of Template:Cvt), with a Template:Cvt wingspan.[8][9] The A. a. anhinga subspecies is larger than A. a. leucogaster and has broader buffy tail tips.[3] They weigh on average around Template:Cvt, with a range of Template:Cvt.[9][10][11] The bill is relatively long (about twice the length of the head), sharply pointed, and yellow, and the webbed feet are yellow as well.[5][12][8][10]

The male is glossy black-green, including its wings and the base of its wings, while its tail is glossy black-blue.[12] The tip of the tail is white.[13] The back of the head and the neck have elongated feathers that have been described as gray[14] or light purple-white.[12] The upper back of the body and wings are spotted or streaked with white.[14]

The female anhinga is similar to the male except for its pale gray-buff[15] or light brown[16] head, neck, and upper chest. The lower chest or breast is a chestnut color, and the back is browner than the male's.[17]

File:Anhinga anhinga 2zz.jpg
Skeleton, showing the hinge-like articulation between the eighth and ninth cervical vertebrae.

The hatchling starts bald but gains tan down within a few days of hatching. Within two weeks, the tan down is replaced by white down. Three weeks after hatching, the first juvenile feathers appear. Juveniles are mostly brown until they first breed, usually after the second or third winter.[2]

Anhinga are similar in size, shape, and behavior to the double-crested cormorant. The two species can be differentiated by their tails, bills, and flight. The tail of the anhinga is wider and longer, only the cormorant's bill has a hook-tip, only the anhinga can glide in flight.[18]

Typical of the genus, anhingas have a "kinked" neck due to the unique "hinge" morphology of the joint between the eighth and ninth cervical vertebrae.[19]

Behavior

Anhingas swim underwater by kicking their webbed feet to pursue their prey, fish or amphibians, which they spear by rapidly outstretching their bent neck. They come up to the surface to consume and swallow prey.[20] Unlike ducks, ospreys and pelicans, which coat their feathers with oils from the uropygial gland, the anhinga does not have this ability; anhingas lack waterproof feathers on their bodies, causing them to be saturated upon immersion into water, while the flight feathers are slightly less wettable. Thus, their habit of basking in the sun with outstretched wings is crucial. Their dense bones, wetted plumage, and neutral buoyancy in water allow them to fully submerge and hunt for underwater prey.[20][21]

Anhingas cannot fly for any extended distance with soaked feathers; if they attempt to fly while wet, notable difficulty is experienced, the birds flapping vigorously while "running" on the water's surface for a short distance (often escaping a perceived threat). Like cormorants, anhingas perch and rest on fallen trees, logs or rocks near the water's edge with wings spread and feathers fanned-open in a semicircular shape, facing away from the sun, in order to dry themselves and absorb the sun's heat.[22] Anhingas also lose body heat relatively fast, and their posture helps them absorb solar radiation from the sun to counteract this.[22] Because an anhinga in the drying position resembles a male turkey, it has been colloquially referred to as the 'water turkey' or 'swamp turkey'.Script error: No such module "Unsubst".

Diet

Script error: No such module "Multiple image". Anhingas feed on moderately sized wetland fishes,[9] amphibians,[23] aquatic invertebrates and insects.[24] In Alabama, the anhinga's diet consists of fishes (such as mullet, sunfish, black bass, catfish, suckers, and chain pickerel), crayfish, crabs, shrimp, aquatic insects, tadpoles, water snakes and small terrapins.[25] In Florida, sunfishes and bass, killifishes, and live-bearing fishes are primarily eaten by the anhingas.[26] Other fish eaten include pupfish and percids.[24]

Anhingas stalk fish underwater, mainly where there is some vegetation. Once they locate their prey, they partly open their bill and stab the fish swiftly. For larger fish, they use both their jaws; for small fish, they may use only the lower jaw.[9] If the fish is too large to forage, the anhinga stabs it repeatedly and then lets it go.[27] Anhingas bring their capture to the surface of the water, toss it backward and engulf it head-first.[26]

Conservation status

The US protects the anhinga under the Migratory Bird Treaty Act of 1918.[28] The number of individual anhingas has not been estimated, but they are considered to be of least concern because of the frequency of their occurrence in their Template:Cvt global range.[29]

References

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  1. ↑ Script error: No such module "citation/CS1".
  2. ↑ a b c Script error: No such module "citation/CS1".
  3. ↑ a b Script error: No such module "citation/CS1".
  4. ↑ Script error: No such module "citation/CS1".
  5. ↑ a b Script error: No such module "citation/CS1".
  6. ↑ Script error: No such module "citation/CS1".
  7. ↑ Script error: No such module "citation/CS1".
  8. ↑ a b Script error: No such module "citation/CS1".
  9. ↑ a b c d Template:Cite AllAboutBirds
  10. ↑ a b Script error: No such module "citation/CS1".
  11. ↑ Script error: No such module "Citation/CS1".
  12. ↑ a b c Script error: No such module "citation/CS1".
  13. ↑ Script error: No such module "citation/CS1".
  14. ↑ a b Script error: No such module "citation/CS1".
  15. ↑ Script error: No such module "citation/CS1".
  16. ↑ Script error: No such module "citation/CS1".
  17. ↑ Script error: No such module "citation/CS1".
  18. ↑ Script error: No such module "citation/CS1".
  19. ↑ Script error: No such module "Citation/CS1".
  20. ↑ a b Script error: No such module "citation/CS1".
  21. ↑ Script error: No such module "Citation/CS1".
  22. ↑ a b Script error: No such module "Citation/CS1".
  23. ↑ Script error: No such module "citation/CS1".
  24. ↑ a b Script error: No such module "citation/CS1".
  25. ↑ Script error: No such module "citation/CS1".
  26. ↑ a b Script error: No such module "Citation/CS1".
  27. ↑ Script error: No such module "Citation/CS1".
  28. ↑ Script error: No such module "citation/CS1".
  29. ↑ Cite error: Script error: No such module "Namespace detect".Script error: No such module "Namespace detect".

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External links

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