Grass wren

This article is about a species of bird from South and Central America. For the genus of Australian birds, see grasswren.

Grass wren
C. p. aequatorialis, Colombia
Conservation status
Least Concern  (IUCN 3.1)[1]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Family:	Troglodytidae
Genus:	Cistothorus
Species:	C. platensis
Binomial name
Cistothorus platensis (Latham, 1790)

C. p. polyglottus
Serra da Canastra National Park, Brasil

The grass wren (Cistothorus platensis) is a species of passerine bird in the family Troglodytidae. It is widely distributed in central and southern America.^[2]

Taxonomy and systematics

The grass wren was described in 1790 by the English ornithologist John Latham and given the binomial name Sylvia platensis.^[3] The type locality is Buenos Aires, Argentina.^[4] The current genus Cistothorus was introduced by the German ornithologist Jean Cabanis in 1850.^[5]

The grass wren and the sedge wren (Cistothorus stellaris) were formerly treated as conspecific. They were split based on the results of a molecular phylogenetic study published in 2014.^[6] This split was accepted in 2018 by the International Ornithological Committee (IOC) and BirdLife International's Handbook of the Birds of the World, in 2019 by the South American Classification Committee of the American Ornithological Society (AOS), and in 2021 by the AOS North American Classification Committee and the Clements taxonomy. As of 2018 the fourth edition of the Howard and Moore Complete Checklist of the Birds of the World had not implemented the split. Taxonomic bodies recognize 17 subspecies of the grass wren.^{[2][7][8][9][10]}

Description

The grass wren is 10 to 10.5 cm (3.9 to 4.1 in) long. Its upperparts are buffy brown with black and buffy whitish streaks on the back. The wings and tail have dusky bands. Its underparts are mostly buffy.^[11]

Distribution and habitat

The grass wren is found discontinuously from central Mexico south through Belize, Guatemala, Honduras, and Nicaragua into Costa Rica, in every mainland South American country except French Guiana and Suriname, and the Falkland Islands.^[2][12]

In Colombia and Ecuador, the grass wren inhabits moist grassy and sedgy parts of paramo, clearings, agricultural areas, and interandean valleys.^[11][13] In Brazil it inhabits cerrado, grassland, and marshes.^[14]

Behavior

Non-breeding

Grass wrens build two types of non‐breeding nest structures: platforms and dummy nests. Platforms are rudimentary accumulations of grasses concealed between vegetation. Dummy and breeding nests are dome‐shaped with a similar structural layer. The function of these non-breeding nests is unclear, but an experimental study suggests that building non‐breeding nests may be an attempt by males to manipulate the decision of females to breed with a mate they might otherwise reject or to start reproduction earlier than optimal for the females.^[15]

Vocalization

The grass wren's song is a "series of short,...high notes such as high rattles, sharp trills, sparrowlike 'tr-tr-tr-tr' and nasal 'zèzèzèzè'."^[14]

Status

The IUCN has assessed the grass wren as being of Least Concern.^[1]

References

1. BirdLife International (2016). "Cistothorus platensis". IUCN Red List of Threatened Species. 2016: e.T103886997A94290566. doi:10.2305/IUCN.UK.2016-3.RLTS.T103886997A94290566.en. Retrieved 20 November 2021.
2. Gill, F.; Donsker, D.; Rasmussen, P. (July 2021). "IOC World Bird List (v 11.2)". Retrieved July 14, 2021.
3. Latham, John (1790). Index Ornithologicus, Sive Systema Ornithologiae: Complectens Avium Divisionem In Classes, Ordines, Genera, Species, Ipsarumque Varietates (in Latin). Vol. 2. London: Leigh & Sotheby. p. 548.
4. Mayr, Ernst; Greenway, James C. Jr, eds. (1960). Check-list of Birds of the World. Vol. 9. Cambridge, Massachusetts: Museum of Comparative Zoology. p. 393.
5. Cabanis, Jean (1850). Museum Heineanum : Verzeichniss der ornithologischen Sammlung des Oberamtmann Ferdinand Heine, auf Gut St. Burchard vor Halberstadt (in German). Vol. 1. Halberstadt: In Commission bei R. Frantz. p. 77.
6. Robbins, Mark B.; Nyári, Árpád S. (2014). "Canada to Tierra del Fuego: species limits and historical biogeography of the Sedge Wren (Cistothorus platensis)". Wilson Journal of Ornithology. 126 (4): 649–662. doi:10.1676/13-162.1. S2CID 86234438.
7. HBW and BirdLife International (2020) Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world Version 5. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v5_Dec20.zip [.xls zipped 1 MB] retrieved May 27, 2021
8. Remsen, J. V., Jr., J. I. Areta, E. Bonaccorso, S. Claramunt, A. Jaramillo, D. F. Lane, J. F. Pacheco, M. B. Robbins, F. G. Stiles, and K. J. Zimmer. Version 24 August 2021. A classification of the bird species of South America. American Ornithological Society. https://www.museum.lsu.edu/~Remsen/SACCBaseline.htm retrieved August 24, 2021
9. "Check-list of North and Middle American Birds". American Ornithological Society. June 29, 2021. Retrieved August 9, 2021.
10. Clements, J. F., T. S. Schulenberg, M. J. Iliff, S. M. Billerman, T. A. Fredericks, J. A. Gerbracht, D. Lepage, B. L. Sullivan, and C. L. Wood. 2021. The eBird/Clements checklist of Birds of the World: v2021. Downloaded from https://www.birds.cornell.edu/clementschecklist/download/ Retrieved August 25, 2021
11. Ridgely, Robert S.; Greenfield, Paul J. (2001). The Birds of Ecuador. Vol. II. Ithaca NY: Cornell University Press. p. 590. ISBN 978-0-8014-8721-7.
12. Herkert, J. R., D. E. Kroodsma, and J. P. Gibbs (2021). Grass Wren (Cistothorus platensis), version 1.1. In Birds of the World. Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.sedwre.01.1 retrieved September 9, 2021
13. McMullan, Miles; Donegan, Thomas M.; Quevedo, Alonso (2010). Field Guide to the Birds of Colombia. ProAves. p. 182. ISBN 978-0-9827615-0-2.
14. van Perlo, Ber (2009). A Field Guide to the Birds of Brazil. Oxford University Press. p. 344. ISBN 978-0-19-530155-7.
15. Llambías, Paulo Emilio; Jefferies, María Milagros; Apaza, Daniel Pascual Cáceres; Garrido, Paula Sabrina; Zarco, Agustín; Arrieta, Ramiro Santiago; Bender, José Benjamin (2020). "Building multiple nests is associated with reduced breeding performance in a south temperate population of Grass Wrens Cistothorus platensis platensis". Ibis. 162 (1): 75–89. doi:10.1111/ibi.12722. ISSN 1474-919X. S2CID 91283835.

Further reading

• Kroodsma, D.; Brewer, D. (2017). del Hoyo, J.; Elliott, A.; Sargatal, J.; Christie, D.A.; de Juana, E. (eds.). "Grass Wren (Cistothorus platensis)". Handbook of the Birds of the World Alive. Lynx Edicions. Retrieved 31 December 2017.
• Kroodsma, Donald E.; Sánchez, Julio; Stemple, David W.; Goodwin, Elijah; Silva, Maria Luisa da; Vielliard, Jacques M.E. (1999). "Sedentary life style of Neotropical sedge wrens promotes song imitation". Animal Behaviour. 57 (4): 855–863. doi:10.1006/anbe.1998.1036. PMID 10202093. S2CID 32688973.
• Traylor, Melvin A. Jnr. (1988). Geographic variation and evolution in South American Cistothorus platensis (Aves, Troglodytidae). Fieldiana Zoology Number 48. Chicago, Illinois: Field Museum of Natural History. pp. 19–28.