Screamer
| Screamer | |
|---|---|
| |
| Southern screamer(Chauna torquata) | |
Scientific classification
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Anseriformes |
| Suborder: | Anhimae Wetmore & Miller 1926 |
| Family: | Anhimidae Stejneger,1885 |
| Genera | |
Thescreamersare three South Americanbirdspecies placed infamilyAnhimidae.They were thought to be related to theGalliformesbecause of similarbills,but are more closely related to the familyAnatidae,i.e.ducksand allies,[1][2]and themagpie goose,[3]within the cladeAnseriformes.The clade is exceptional within the living birds in lackinguncinate processes of ribs.[4]The three species are: Thehorned screamer(Anhima cornuta); thesouthern screameror crested screamer (Chauna torquata); and thenorthern screameror black-necked screamer (Chauna chavaria).
Systematics and evolution
[edit]Screamers have a poor fossil record. A putativeEocenespecimen is known fromWyoming,while the more modernChaunoides antiquusis known from the lateOligoceneto earlyMioceneinBrazil.Anhimids are most similar topresbyornithids,with which they 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 frompresbyornithid-gradebirds, reverting from a filter-feeding lifestyle to an herbivorous one.[5]
| Image | Genus | Living Species |
|---|---|---|
 |
Anhima |
|
 |
Chauna |
|
Distribution and habitat
[edit]The three species occur only inSouth America,ranging fromColombiato northernArgentina.The horned screamer was once present on theCaribbeanisland ofTrinidad,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 largespurson their wings which are used in fights over mates and territorial disputes;[2]these can break off in the breast of other screamers, and are regularly renewed. Unlike ducks, they have a partialmoultand are able to fly throughout the year.[2]They live in open areas and marshes with some grass and feed on water plants. One species, the southern screamer, is considered apestas it raids crops and competes with farm birds.
Behaviour and ecology
[edit]Screamers typical lay 4–5 white eggs, with clutches ranging between 2 and 7. Like mostAnseriformes,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 chicksimprintearly 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
[edit]Both the southern and the horned screamer remain widespread and are overall fairly common.[6][7]In contrast, the northern screamer is relatively rare and consequently considerednear threatened.[8]They are seldomhunted,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]The main threats arehabitat destructionand increased intensification of agriculture.[8]
References
[edit]- ^ Carboneras, C. (1992). "Family Anhimidae (Screamers)". In del Hoyo, J.; Elliott, A.; Sargatal, J. (eds.).Handbook of the Birds of the World.Vol. 1, Ostrich to Ducks. Barcelona, ES: Lynx Edicions. pp. 528–535.ISBN84-87334-09-1.
- ^abc Todd, Frank S. (1991). Forshaw, Joseph (ed.).Encyclopaedia of Animals: Birds.London, UK: Merehurst Press. p. 87.ISBN1-85391-186-0.
- ^ Kricher, John C. (1997).A Neotropical Companion.Princeton, NJ: Princeton University Press. p. 213.ISBN0-691-04433-3– via Google Books.
- ^ Fowler, M.E.; Cubas, Z.S. (2001).Biology, Medicine, and Surgery of South American Wild Animals.Wiley-Blackwell. p. 103.
- ^ de Pietri, Vanesa L.; Scofield, R. Paul; Zelenkov, Nikita; Boles, Walter E.; Worthy, Trevor H. (2016)."The unexpected survival of an ancient lineage of anseriform birds into the Neogene of Australia: The youngest record of Presbyornithidae".Royal Society Open Science.3(2): 150635.doi:10.1098/rsos.150635.PMC4785986.
- ^ "Southern ScreamerChauna torquata".IUCN Red List of Threatened Species.2016.BirdLife International:e.T22679729A92826769. 2016.doi:10.2305/IUCN.UK.2016-3.RLTS.T22679729A92826769.en.Retrieved29 December2022.
- ^ "Anhima cornuta".IUCN Red List of Threatened Species.2016.BirdLife International:e.T22679723A92826187. 2016.doi:10.2305/IUCN.UK.2016-3.RLTS.T22679723A92826187.en.Retrieved29 December2022.
- ^ab "Chauna chavaria".IUCN Red List of Threatened Species.2016.BirdLife International:e.T22679726A92826428. 2016.doi:10.2305/IUCN.UK.2016-3.RLTS.T22679726A92826428.en.Retrieved29 December2022.
External links
[edit]- Screamer videos.Internet Bird Collection(video shorts, sound recordings, and photographs). Archived from the original on 2016-04-11.Retrieved2023-07-18.
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