Editing Northern screamer

{{short description|Species of bird}}
{{Use American English|date=September 2022}}

{{speciesbox
| name = Northern screamer
| image = Chauna chavaria-8.jpg
| status = NT
| status_system = IUCN3.1
| status_ref = <ref name=IUCN>{{cite iucn |author=BirdLife International |date=2016 |title=''Chauna chavaria'' |volume=2016 |page=e.T22679726A92826428 |doi=10.2305/IUCN.UK.2016-3.RLTS.T22679726A92826428.en |access-date=30 September 2022}}</ref>
| genus = Chauna
| species = chavaria
| authority = ([[Carl Linnaeus|Linnaeus]], 1766)
| range_map = Northern Screamer Range.png
| range_map_caption = Distribution map 
| synonyms = ''Parra chavaria'' {{small|Linnaeus,&nbsp;1766}}
}}

The '''northern screamer''' ('''''Chauna chavaria''''') is a [[Near-threatened species|Near Threatened]] species of bird in family [[Anhimidae]] of the [[waterfowl]] order [[Anseriformes]]. It is found in [[Colombia]] and [[Venezuela]].<ref name=IOC12.2>{{cite web |url=https://www.worldbirdnames.org/new/bow/waterfowl/ |title=Screamers, ducks, geese, swans |website=IOC World Bird List |version =v 12.2 |editor-last1=Gill |editor-first1= F. |editor-last2=Donsker|editor-first2=D.|editor-last3=Rasmussen |editor-first3=P. |date=August 2022 |access-date=August 9, 2022 }}</ref>

==Taxonomy and systematics==

The northern screamer shares genus ''Chauna'' with the [[southern screamer]] (''C. torquata''). One other species, the [[horned screamer]] (''Anhima cornuta'') is also in family Anhimidae. The northern screamer is [[monotypic]].<ref name=IOC12.2/>

==Description==

The northern screamer is {{convert|76|to|91|cm|in|abbr=on}} long. They are stout bodied with a disproportionately small head and a gray bill. The sexes have the same plumage. Adults have a gray crown with a long crest, a mostly white face, a wide black band around the neck, and a dark gray body, wings, and tail. Their wing has two sharp spurs at its [[Manus (anatomy)|manus]]. They have bare red skin around their brown eye and reddish orange legs and feet. Juveniles are similar to adults but drabber.<ref name=NOSC-BOW>Carboneras, C., P. F. D. Boesman, G. M. Kirwan, and C. J. Sharpe (2020). Northern Screamer (''Chauna chavaria''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.norscr1.01 retrieved September 30, 2022</ref>

==Distribution and habitat==

The northern screamer is found across northern Colombia from the [[Atrato River]] and [[Magdalena River]] valleys east into the [[Lake Maracaibo]] area of Venezuela. It inhabits a variety of wet landscapes including swamps, marshes, lagoons, riverbanks, and seasonally flooded river plains.<ref name=NOSC-BOW/>

==Behavior==
===Movement===

The northern screamer is essentially sedentary but local wandering by non-breeders and juveniles is suspected.<ref name=NOSC-BOW/>

===Feeding===

The northern screamer feeds on the leaves, stems, and roots of aquatic plants. They usually graze like geese, sometimes in loose flocks.<ref name=NOSC-BOW/>

===Breeding===
[[File:Chauna chavaria carpometacarpus.png|thumb|261x261px|Diagram of the carpometacarpus of Chauna chavaria, the bone which both manual spurs are attached to. The carpometacarpus consists of several fused bones from both the second digit (yellow) and the third digit (green) of the manus. Keratin caps (blue) cover the spurs and the thumb claw (red).]]
The northern screamer is territorial during the breeding season. The pair build a mound of plant material and debris as a nest. Breeding can be at any time of year but most eggs are laid in October and November. The typical clutch size is three to five eggs but can be up to seven. Both parents incubate the eggs and care for the young. The incubation period is 42 to 44 days; fledging occurs eight to ten weeks after hatch and the young are independent after about 12 weeks.<ref name=NOSC-BOW/>

{{birdsong|url=https://xeno-canto.org/species/Chauna-chavaria |species=northern screamer}}
===Vocalization===

The northern screamer, like others of its family, is very vocal. Its primary vocalization is a "single, rather high-pitched yelping call...'kleer-a-ruk, cherio'."<ref name=NOSC-BOW/>

==Status==

The [[IUCN]] originally assessed the northern screamer as Threatened. Since 2004 has treated it as Near Threatened but it nearly again meets the criteria for Threatened status. It has a somewhat limited range and its estimated population of between 1500 and 7000 mature individuals is believed to be decreasing.<ref name=IUCN/> It occurs in several protected areas in Colombia but even they have suffered from [[habitat destruction]]. The species is also affected by egg collecting and hunting for food, domestic and industrial pollution of its habitat, and urbanization.<ref name=NOSC-BOW/>

==References==
{{reflist}}

{{Taxonbar|from=Q997306}}

[[Category:Anhimidae]]
[[Category:Birds of Colombia]]
[[Category:Birds of Venezuela]]
[[Category:Birds described in 1766]]
[[Category:Taxa named by Carl Linnaeus]]