View source for Screamer

{{Short description|Family of birds}}
{{Other uses}}
{{Automatic taxobox
| parent_authority = Wetmore & Miller 1926 
| taxon=Anhimidae
| image = At Possa da Londra in the Brazilian Patanal (105m) - the weird looking Southern Screamer (Chauna torquata) - (24213807344).jpg
| image_caption = [[Southern screamer]] (''Chauna torquata'')
| subdivision_ranks = [[Genera]]
| subdivision =
* ''[[Anhima]]''
* ''[[Chauna]]''
* ''†[[Chaunoides]]''
| authority = [[Leonhard Hess Stejneger|Stejneger]], 1885
}}

The '''screamers''' are three South American [[bird]] species placed in [[Family (biology)|family]] '''Anhimidae'''. They were thought to be related to the [[Galliformes]] because of similar [[beak|bills]], but are more closely related to the family [[Anatidae]], i.e. [[duck]]s and allies,<ref name=Carboneras-1992/><ref name=Todd/> and the [[magpie goose]],<ref name=Kricher/> within the clade [[Anseriformes]]. The clade is exceptional within the living birds in lacking [[uncinate processes of ribs]].<ref name=Fowler-Cubas-2001/> The three species are: The [[horned screamer]] (''Anhima cornuta''); the [[southern screamer]] or crested screamer (''Chauna torquata''); and the [[northern screamer]] or black-necked screamer (''Chauna chavaria'').

==Systematics and evolution==
Anhimids are most similar to [[Presbyornithidae|presbyornithid]]s, with which they may form a clade to the exclusion of the rest of Anseriformes. Given the presence of lamelae in the otherwise fowl-like beaks of screamers, it is even possible that they evolved from [[Presbyornithidae|presbyornithid-grade]] birds, reverting from a filter-feeding lifestyle to an herbivorous one.<ref name=dePietri-Schofield-etal-2016/>

Screamers have a poor fossil record. ''[[Anachronornis]]'' from the [[Eocene]] of [[Wyoming]] was originally suggested to be a screamer but is now though to be a basal [[Anseriformes|anseriform]], while the more modern ''[[Chaunoides antiquus]]'' is known from the late [[Oligocene]] to early [[Miocene]] in [[Brazil]]. ''[[Eoneornis]]'' from the Miocene of Argentina was originally described as an indeterminate anseriform but shows some similarities with Anhimidae, especially ''Chaunoides''.<ref>{{cite journal |last1=Cenizo|first1=M.M. |last2=Agnolín|first2=F.L.|year=2010|title=The southernmost records of Anhingidae and a new basal species of Anatidae (Aves) from the lower–middle Miocene of Patagonia, Argentina|journal=Alcheringa |volume=34|issue=4|pages=493–514| url=https://www.tandfonline.com/doi/full/10.1080/03115511003793504| doi=10.1080/03115511003793504|url-access=subscription}}</ref>

{| class="wikitable"
|-
! Image !! Genus   !! Living species
|-
|[[File:Anhima cornuta - Horned screamer.jpg|120px]]||''Anhima ''  || 
*  [[horned screamer]], (''Anhima cornuta'')
|-
|[[File:Southern Screamer RWD2.jpg|120px]]||''[[Chauna]]''  || 
* [[Southern screamer]] or crested screamer, ''Chauna torquata''
* [[Northern screamer]] or black-necked screamer, ''Chauna chavaria''
|-
|}

==Distribution and habitat==
The three species occur only in [[South America]], ranging from [[Colombia]] to northern [[Argentina]]. The horned screamer was once present on the [[Caribbean]] island of [[Trinidad]], but is now extirpated from there. They are large, bulky birds, with a small downy head, long legs and large feet which are only partially webbed. They have large [[Spur (zoology)|spurs]] on their wings which are used in fights over mates and territorial disputes;<ref name=Todd/> these can break off in the breast of other screamers, and are regularly renewed. Unlike ducks, they have a partial [[moult]] and are able to fly throughout the year.<ref name=Todd/> They live in open areas and marshes with some grass and feed on water plants. One species, the southern screamer, is considered a [[pest (animal)|pest]] as it raids crops and competes with farm birds.

==Behaviour and ecology==
Screamers typically lay 4–5&nbsp;white eggs, with clutches ranging between 2 and 7&nbsp;. Like most [[Anseriformes]], the chicks can run as soon as they are hatched. They can swim better than they can run, so young screamers are usually raised in or near water, where they can better avoid predators. Like ducks, screamer chicks [[Imprinting (psychology)|imprint]] early in life. That, and their unspecialized omnivorous diet makes them amenable to domestication. They can be excellent guard animals, due to their loud alarm calls ("screams") when encountering anything new and possibly threatening.

==Status and conservation==
Both the southern and the horned screamer remain widespread and are overall fairly common.<ref name=IUCN-Southern-Screamer/><ref name=IUCN-Horned-Screamer/> In contrast, the northern screamer is relatively rare and consequently considered [[near threatened]].<ref name=IUCN-Northern-Screamer/> They are seldom [[Hunting|hunt]]ed, in spite of their conspicuous nature, because their flesh has a spongy texture and is riddled with air-sacs, making it highly unpalatable.{{citation needed|date=December 2022}} The main threats are [[habitat destruction]] and increased intensification of agriculture.<ref name=IUCN-Northern-Screamer/>

== References ==
{{reflist|25em|refs=

<ref name=Carboneras-1992>
{{cite book
 |last=Carboneras |first=C.
 |year=1992
 |section=Family Anhimidae (Screamers)
 |editor1-last=del Hoyo |editor1-first=J.
 |editor2-last=Elliott |editor2-first=A.
 |editor3-last=Sargatal |editor3-first=J.
 |title=Handbook of the Birds of the World
 |volume=1, Ostrich to Ducks
 |place=Barcelona, ES
 |pages=528–535
 |publisher=Lynx Edicions
 |isbn=84-87334-09-1
}}
</ref>

<ref name=dePietri-Schofield-etal-2016>
{{cite journal
 |first1=Vanesa L.  |last1=de&nbsp;Pietri         |first2=R. Paul    |last2=Scofield
 |first3=Nikita     |last3=Zelenkov               |first4=Walter E.  |last4=Boles
 |first5=Trevor H.  |last5=Worthy
 |year=2016
 |title=The unexpected survival of an ancient lineage of anseriform birds into the Neogene of Australia: The youngest record of Presbyornithidae
 |journal=Royal Society Open Science
 |volume=3 |issue=2 |article-number=150635
 |doi=10.1098/rsos.150635
|pmid=26998335 |pmc=4785986|bibcode=2016RSOS....350635D }}
</ref>

<ref name=Fowler-Cubas-2001>
{{cite book
 |last1=Fowler |first1=M.E.
 |last2=Cubas  |first2=Z.S.
 |year=2001
 |title=Biology, Medicine, and Surgery of South American Wild Animals
 |publisher=Wiley-Blackwell
 |page=103
}}
</ref>

<ref name=IUCN-Horned-Screamer>
{{cite iucn
 |publisher=[[BirdLife International]]
 |year=2016
 |title=''Anhima cornuta''
 |volume=2016
 |article-number=e.T22679723A92826187
 |doi=10.2305/IUCN.UK.2016-3.RLTS.T22679723A92826187.en
 |access-date=29 December 2022
}}
</ref>

<ref name=IUCN-Northern-Screamer>
{{cite iucn
 |publisher=[[BirdLife International]]
 |year=2016 |title=''Chauna chavaria''
 |volume=2016
 |article-number=e.T22679726A92826428
 |doi=10.2305/IUCN.UK.2016-3.RLTS.T22679726A92826428.en
 |access-date=29 December 2022
}}
</ref>

<ref name=IUCN-Southern-Screamer>
{{cite iucn
 |publisher=[[BirdLife International]]
 |year=2016
 |title=Southern Screamer ''Chauna torquata''
 |volume=2016
 |article-number=e.T22679729A92826769
 |doi=10.2305/IUCN.UK.2016-3.RLTS.T22679729A92826769.en
 |access-date=29 December 2022
}}
</ref><br/>&nbsp;

<ref name=Kricher>
{{cite book
 | first=John C. | last=Kricher
 | year=1997 | title=A Neotropical Companion
 | location=Princeton, NJ
 | publisher=Princeton University Press
 | isbn=0-691-04433-3
 | page=213
 | url=https://books.google.com/books?id=b2sZBgAAQBAJ&pg=PA213
 | via=Google Books
}}
</ref>

<ref name=Todd>
{{cite book
 |last = Todd |first = Frank S.
 |year = 1991
 |editor-last = Forshaw |editor-first = Joseph
 |title = Encyclopaedia of Animals: Birds
 |location = London, UK
 |publisher = Merehurst Press
 |isbn = 1-85391-186-0
 |page = 87
}}
</ref>

}} <!-- end "refs=" -->

==External links==
* {{cite AV media
 |title=Screamer videos
 |website=Internet Bird Collection
 |medium=video shorts, sound recordings, and photographs
 |url=http://ibc.lynxeds.com/family/screamers-anhimidae
 |url-status=usurped |access-date=2023-07-18
 |archive-url=https://web.archive.org/web/20160411203922/http://ibc.lynxeds.com/family/screamers-anhimidae
 |archive-date=2016-04-11
}}

{{Taxonbar|from=Q217484}}
{{Authority control}}

[[Category:Anhimidae| ]]
[[Category:Birds of South America]]
[[Category:Exotic pets]]
[[Category:Taxa named by Leonhard Stejneger]]