Darwin's rhea

{{Short description|Species of bird}} {{Use dmy dates|date=November 2021}} {{Speciesbox | name = Darwin's rhea | status = LC | image = {{CSS image crop |Image = Lesser rhea (Rhea pennata pennata) Torres del Paine.jpg |bSize = 400 |cWidth = 220 |cHeight = 240 |oTop = 20 |oLeft = 50 }}

| image_caption = Torres del Paine, Chile | status_system = IUCN3.1 | status_ref = <ref name="iucn status">{{cite iucn |author=BirdLife International |year=2022 |title=''Rhea pennata'' |article-number=e.T22678081A217016710 |doi=10.2305/IUCN.UK.2022-2.RLTS.T22678081A217016710.en}}</ref> | status2 = CITES_A1 | status2_system = CITES | status2_ref = <ref>{{Cite web|title=Appendices {{!}} CITES|url=https://cites.org/eng/app/appendices.php|access-date=2022-01-14|website=cites.org}}</ref>{{NoteTag|''Pterocnemia pennata pennata'' is included in Appendix II.}} | genus = Rhea | species = pennata | authority = d'Orbigny, 1837<ref>{{cite journal |last1=Dickinson |first1=Edward C. |title=Conflicting options for the first available use of the name ''Rhea pennata'' d'Orbigny and the date to be used |journal=Zoological Bibliography |date=8 March 2019 |volume=5 |issue=9 |pages=403–404 |url=https://www.biodiversitylibrary.org/page/63787898#page/409/mode/1up |access-date=1 December 2024}}</ref> | range_map = Pterocnemia pennata Distribution map.jpg | subdivision_ranks = Subspecies | subdivision = * ''R. p. garleppi'' (Chubb, 1913)<ref name ="SN"/> * ''R. p. pennata'' d'Orbigny, 1837<ref name="SN" /> * ''R. p. tarapacensis'' (Chubb, 1913) | synonyms = {{collapsable list| |''Pterocnemia pennata'' (d'Orbigny, 1837) |''Rhea darwinii'' Gould, 1837<ref name=Peters>Peters, James L. (1979)</ref><ref>{{cite journal |last1=Gould |first1=J. |title=On a New Rhea (''Rhea Darwinii'') from Mr. Darwin's Collection |journal=Proceedings of the Zoological Society of London |date=1837 |volume=5 |issue=51 |page=35 |url=https://www.biodiversitylibrary.org/page/30570920}}</ref> |''Rhea pennata darwinii'' Gould, 1837 |''Rhea nana'' Lydekker, 1894 |''Rhea pennata nana'' Lydekker, 1894 |''Pterocnemia pennata garleppi'' Chubb, 1913 |''Pterocnemia tarapacensis garleppi'' Chubb, 1913 |''Pterocnemia tarapacensis'' Chubb, 1913 |''Rhea tarapacensis'' (Chubb, 1913) |''Rhea tarapacensis tarapacensis'' (Chubb, 1913) }} }}

'''Darwin's rhea''' or the '''lesser rhea''' ('''''Rhea pennata''''') is a large flightless bird, the smaller of the two extant species of rheas. It is found in the Altiplano and Patagonia in South America.

==Description== thumb|A family of ''Rhea pennata pennata'' in the wild in Chile, 2006 [[File:Pterocnemia pennata head Edinburgh Zoo.jpg|thumb|Head of a Darwin's rhea at the Edinburgh Zoo]]

The lesser rhea stands at {{convert|90|to(-)|100|cm|in|abbr=on}} tall. Length is {{convert|92|to(-)|100|cm|in|abbr=on}} and weight is {{convert|15|to(-)|28.6|kg|lb|abbr=on}}.<ref name="Davies" /><ref>Elliott, Andrew (1992)</ref> Like most ratites, it has a small head and a small bill, the latter measuring {{convert|6.2|to|9.2|cm|in|abbr=on}}, but has long legs and a long neck. It has relatively larger wings than other ratites, enabling it to run particularly well. It can reach speeds of 60 km/h (37 mph), enabling it to outrun predators. The sharp claws on the toes are effective weapons. Their feathers are similar to those of ostriches, in that they have no aftershaft.<ref name=Perrins>Perrins, C. (1987)</ref> Their plumage is spotted brown and white, and the upper part of their tarsus is feathered.<ref name="Davies" /> The tarsus is {{convert|28|to|32|cm|in|abbr=on}} long and has 18 horizontal plates on the front.<ref name="Davies"/>

==Etymology== It is known as ''ñandú petiso'', or ''ñandú del norte'', in Argentina, where the majority live. Other names are ''suri'' and ''choique''. The name ''ñandú'' comes from the greater rhea's name in Guaraní, ''ñandu guazu'', meaning big spider, possibly in relation to their habit of alternately opening and lowering their wings when they run. In English, Darwin's rhea gets its scientific name from Rhea, a Greek goddess, and ''pennata'', meaning winged. The specific name was bestowed in 1837 by Darwin's contemporary and rival Alcide d'Orbigny, who first described the bird to Europeans from a specimen from the lower Río Negro south of Buenos Aires, Argentina.<ref name="Davies">Davies, S.J.J.F. (2003)</ref><ref>Krulwich, R. (2009)</ref> As late as 2008, it was classified in the monotypic genus ''Pterocnemia''. This word is formed from two Greek words ''pteron'', meaning feathers, and ''knēmē'', meaning the leg between the knee and the ankle, hence feather-legged, alluding to their feathers that cover the top part of the leg.<ref>Gotch, A.T. (1995)</ref> In 2008, the SACC subsumed ''Pterocnemia'' into the genus ''Rhea''.<ref>Nores, M. (2008)</ref>

==Taxonomy== Three subspecies have traditionally been recognized: * ''R. p. garleppi'' is found in the puna of southeastern Peru, southwestern Bolivia, and northwestern Argentina.<ref name = "Clements, J (2007)">Clements, J (2007)</ref> * ''R. p. tarapacensis'' is found in the puna of northern Chile from the region of Arica and Parinacota to Antofagasta.<ref name = Chile>Jaramillo ''et al.'' (2003)</ref> * ''R. p. pennata'' is found in the Patagonian steppes of Argentina and Chile.<ref name="iucn status" /><ref name = "Clements, J (2007)"/>

The IUCN formerly considered the two northern taxa ''R. p. tarapacensis'' and ''R. p. garleppi'' as a separate species, the puna rhea (''R. tarapacensis'').<ref name="BirdLife International tarapacensis" /><ref name=Chile/> Both ''garleppi'' and ''tarapacensis'' were described by Charles Chubb in 1913.<ref name ="SN">Brands, S. (2008)</ref> The IUCN now recognizes them as one species, but notes the need for more work on the taxonomy of this species.<ref name="iucn status"/> It is possible ''garleppi'' should be considered a junior synonym of ''tarapacensis''.

==Behavior== The lesser rhea is mainly a herbivore, with the odd small animal (lizards, beetles, grasshoppers) eaten on occasion. It predominantly eats saltbush and fruits from cacti, as well as grasses, roots, seeds, and leaves.<ref name="Davies"/><ref>{{cite web | url=https://animaldiversity.org/accounts/Pterocnemia_pennata/ | title=Pterocnemia pennata (Lesser rhea) | website=Animal Diversity Web }}</ref> They tend to be quiet birds, except as chicks when they whistle mournfully, and as males looking for a female, when they emit a booming call.<ref name="Davies"/>

The males of this species become aggressive once they are incubating eggs, even towards females. The females thus lay the later eggs near the nest, rather than in it. Most of the eggs are moved into the nest by the male, but some remain outside, where they rot and attract flies. The male, and later the chicks, eat these flies. The incubation period is 30–44 days, and the clutch size is from 5–55 eggs. The eggs are {{convert|87|to(-)|126|mm|in|abbr=on}} and are greenish yellow.<ref name="Davies" /> Chicks mature by three years of age. Outside the breeding season, Darwin's rhea is quite sociable: it lives in groups of from 5 to 30 birds, of both sexes and a variety of ages.<ref name="Davies" />

==Distribution and habitat==

Darwin's rhea lives in areas of open scrub in the grasslands of Patagonia and on the Andean plateau (the Altiplano), through the countries of Argentina, Bolivia, Chile, and Peru.<ref name="iucn status" /> All subspecies prefer grasslands, brushlands and marshland. However, the nominate subspecies prefers elevations less than {{convert|1500|m|ft|abbr=on}},<ref name="iucn status" /> where the other subspecies typically range from {{convert|3000|to(-)|4500|m|ft|abbr=on}}, but locally down to {{convert|1220|m|ft|abbr=on}} in the south.<ref name="BirdLife International tarapacensis">Birdlife International (2016)</ref>

==History of the discovery of the genus ''Rhea''== [[File:Image-Rhea Darwinii1.jpg|upright=1.1|thumb|right|Illustration of Darwin's rhea, published in 1841 in John Gould's description of birds collected on the second voyage of HMS ''Beagle'']] During the second voyage of HMS ''Beagle'', the young naturalist Charles Darwin made many trips on land, and around August 1833 heard from gauchos in the Río Negro area of Northern Patagonia about the existence of a smaller rhea, "a very rare bird which they called the Avestruz Petise". He continued searching fruitlessly for this bird, and the ''Beagle'' sailed south, putting in at Port Desire in southern Patagonia on 23 December. On the following day, Darwin shot a guanaco (similar to a llama) which provided them with a Christmas meal, and in the first days of January, the artist Conrad Martens shot a rhea which they enjoyed eating before Darwin realised that this was the elusive smaller rhea rather than a juvenile, and preserved the head, neck, legs, one wing, and many of the larger feathers. As with his other collections, these were sent to John Stevens Henslow in Cambridge. On 26 January the ''Beagle'' entered the Straits of Magellan, and at St Gregory's Bay Darwin met Patagonians he described as "excellent practical naturalists". A half Indian, who had been born in the Northern Provinces, told him that the smaller rheas were the only species this far south, while the larger rheas kept to the north. On an expedition up the Santa Cruz River, they saw several of the smaller rheas, which were too wary to be approached closely or caught.<ref name=B63-271>{{harvnb|Barlow|1963|pp=[http://darwin-online.org.uk/content/frameset?viewtype=text&itemID=F1577&pageseq=73 271–5].}}</ref><ref>{{harvnb|Keynes|2001|pp=[http://darwin-online.org.uk/content/frameset?pageseq=244&itemID=F1925&viewtype=text 212], [http://darwin-online.org.uk/content/frameset?pageseq=249&itemID=F1925&viewtype=text 217–218]}}</ref>

In 1837, Darwin's rhea was described as ''Rhea darwinii'' (later synonymized with ''R. pennata'') by the ornithologist John Gould in a presentation to the Zoological Society of London, in which he was followed by Darwin reading a paper on the eggs and distribution of the two species of rheas.<ref name = "Darwin, C (1837)">Darwin, C (1837)</ref>

When Gould classified Darwin's rhea and the greater rhea as separate species, he confirmed a serious problem for Darwin. These birds mainly live in different parts of Patagonia, but there is also an overlapping zone where the two species coexist. As every living being had been created in a fixed form, as accepted by the science of his time, they could only change their appearance by a perfect adaptation to their way of life, but would still be the same species. But now he had to deal with two different species. This started to form his idea that species were not fixed at all, but that another mechanism might be at work.<ref>Herbert, S (1980)</ref>

==Conservation== [[File:Pterocnemia pennata MWNH 0002.JPG|thumb|upright=1.1|Rhea's egg, in the Museum Wiesbaden, Germany]]

Darwin's rhea is categorized as least concern by the IUCN.<ref name="iucn status" /> The former southern nominate subspecies remains relatively widespread and locally fairly common. Its range is estimated at {{convert|859000|km2|sqmi|abbr=on}}.<ref name="iucn status" /> The situation for the two former northern subspecies is more worrying, with their combined population estimated as being possibly as low as in the hundreds.<ref name="BirdLife International tarapacensis" /> However, they are classified as ''Rhea tarapacensis'' by the IUCN, which regards it as being near threatened, with the primary threats being hunting, egg-collecting, and fragmentation of its habitat due to conversion to farmland or pastures for cattle-grazing.<ref name="BirdLife International tarapacensis" /><ref name="Davies" />

Patagonia National Park in Chile's Aysén Region hosts the Centro de Reproducción para la Conservación del Ñandú ('Reproduction Centre for Darwin's rhea Conservation').<ref name=Conaf2020>{{Cite web|url=https://www.conaf.cl/recuperando-al-nandu-en-la-region-de-aysen/|title=Recuperando al ñandú en la región de Aysén|date=2021-05-11|access-date=2022-01-08|website=Conaf|language=Spanish}}</ref><ref name=coop7jul>{{Cite news|title=Incendio en Parque Nacional Patagonia fue causado por "colapso" de estufa producto de fuertes vientos|url=https://www.cooperativa.cl/noticias/pais/region-de-aysen/incendio-en-parque-nacional-patagonia-fue-causado-por-colapso-de/2021-07-07/014127.html|date=July 7, 2021|access-date=January 12, 2022|work=Radio Cooperativa|language=Spanish}}</ref> The centre is run by Tompkins Conservation with the support of the National Forest Corporation.<ref name=Conaf2020/> {{clear left}}

==Notes== {{NoteFoot}}

==References== ===Footnotes=== {{Reflist}}

===Sources cited=== {{Commons category|Rhea pennata}} {{refbegin}} * {{cite journal |last=Barlow |first=Nora |title=Darwin's ornithological notes |url=http://darwin-online.org.uk/content/frameset?itemID=F1577&viewtype=text&pageseq=1 |date=1963 |journal=Bulletin of the British Museum (Natural History), Historical Series |volume=2 |issue=7 |pages=201–278|doi=10.5962/p.310422 |doi-access=free }} * {{cite web | url=http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=3&m=0 | title=Lesser Rhea - BirdLife Species Factsheet | access-date=6 February 2009 | author=BirdLife International | author-link=BirdLife International | year=2008b | work=Data Zone | archive-date=4 January 2009 | archive-url=https://web.archive.org/web/20090104234840/http://www.birdlife.org/datazone/species/index.html?action=SpcHTMDetails.asp&sid=3&m=0 }} * {{cite iucn |author=BirdLife International |year=2016 |title=''Rhea tarapacensis'' |article-number=e.T22728206A94974751 |doi=10.2305/IUCN.UK.2016-3.RLTS.T22728206A94974751.en}} * {{cite web |url=http://www.taxonomy.nl/Main/Classification/99286.htm |title=Systema Naturae 2000 / Classification, Rhea pennata |access-date=4 February 2009 |last=Brands |first=Sheila |date=14 August 2008 |work=Project: The Taxonomicon |archive-url=https://web.archive.org/web/20100313074639/http://www.taxonomy.nl/Main/Classification/99286.htm |archive-date=13 March 2010 }} * {{cite book |last1=Clements |first1=James |title=The Clements Checklist of the Birds of the World |edition=6th |year=2007 |publisher= Cornell University Press|location=Ithaca, NY |isbn=978-0-8014-4501-9 }} * {{cite journal |last1=Darwin|first1= Charles |year=1837 |title=Notes on Rhea americana and Rhea darwinii |journal=Proceedings of the Zoological Society of London |volume=5 |issue=51 |pages=35–36 |url=http://darwin-online.org.uk/content/contentblock?hitpage=1&viewtype=text&basepage=1&itemID=F1643#1 |id={{BHL page|30570920}} |doi=10.1111/j.1469-7998.1837.tb06823.x |url-access=subscription }} * {{cite encyclopedia |last=Davies |first=S.J.J.F.|editor=Hutchins, Michael |encyclopedia=Grzimek's Animal Life Encyclopedia |title=Rheas |edition=2nd |year=2003 |publisher=Gale Group |volume=8 Birds I Tinamous and Ratites to Hoatzins |location=Farmington Hills, MI|isbn=0-7876-5784-0 |pages=69–74}} * {{cite encyclopedia |last=Elliott |first=Andrew |editor=Hoyo, Joseph del |encyclopedia=Handbook of the Birds of the World |title=Lesser Rhea |url=https://archive.org/details/handbookofbirdso0001unse |year=1992 |publisher=Lynx Edicions |volume=1 (Ostrich to Ducks) |isbn=978-84-87334-10-8 |url-access=registration }} * {{cite book |last1=Gotch |first1=A.F. |title=Latin Names Explained. A Guide to the Scientific Classifications of Reptiles, Birds & Mammals|year= 1995 |orig-date=1979 |publisher=Facts on File |location=London|isbn=0-8160-3377-3|page=176|chapter=15}} * {{cite journal |last1=Herbert|first1=Sandra |year=1980 |title= The Red Notebook of Charles Darwin |journal= Bulletin of the British Museum (Natural History) |series=7 |pages=1–164 |url=http://darwin-online.org.uk/content/contentblock?hitpage=110&viewtype=text&basepage=1&itemID=F1583e#110 }} * {{cite book |last1=Jaramillo |first1=Alvaro |last2= Burke |first2= Peter |last3= Beadle |first3= David | title=Birds of Chile |year=2003 |publisher= Christopher Helm|location=London |isbn=0-7136-4688-8 }} *{{Citation | last= Keynes | first= Richard | author-link = Richard Keynes | year= 2001 | title=Charles Darwin's Beagle Diary | publisher=Cambridge University Press | url =http://darwin-online.org.uk/content/frameset?itemID=F1925&viewtype=text&pageseq=1 | access-date =1 August 2019 }} * {{cite web| url= https://www.npr.org/templates/story/story.php?storyId=101090483 | title=Darwin's Very Bad Day: 'Oops, We Just Ate It!' | access-date= 6 June 2009 |last=Krulwich | first= Robert | date= 24 February 2009 | publisher=NPR }} * {{cite web|url=http://lacaledoniasur.com.ar/english/choique.html |title=The revered bird of native people. |author=La Caledonia Sur |access-date=9 December 2011 |archive-url=https://web.archive.org/web/20120426041532/http://lacaledoniasur.com.ar/english/choique.html |archive-date=26 April 2012 }} * {{cite web | url= http://www.museum.lsu.edu/~Remsen/SACCprop348.html | title= Incluir Pterocnemia dentro de Rhea | access-date= 4 February 2009 | last= Nores | first= Manuel | date= 7 August 2008 | work= South American Classification Committee | publisher= American Ornithologists' Union | archive-url= https://web.archive.org/web/20080920120305/http://www.museum.lsu.edu/~Remsen/SACCprop348.html | archive-date= 20 September 2008 }} * {{cite book |last=Perrins |first=Christopher |editor1-last=Harrison |editor1-first=C.J.O. |title=Birds: Their Lifes, Their Ways, Their World |url=https://archive.org/details/birdstheirlifeth00came/page/168 |orig-date=1979 |year=1987 |publisher=Reader's Digest Association, Inc. |location=Pleasantville, NY, US |isbn=0-89577-065-2 |pages=[https://archive.org/details/birdstheirlifeth00came/page/168 168–170] |url-access=registration }} * {{cite book |last1=Peters|first1=James Lee |author-link1=James Lee Peters |title=Checklist of Birds of the World |url=https://archive.org/download/checklistofbirds12pete/checklistofbirds12pete.pdf |edition=2nd |volume=1 |year=1979|publisher=Museum of Comparative Zoology |location=Cambridge, MA |pages=6–7 }} {{refend}}

Category:Rheidae Category:Ratites Category:Domesticated birds Category:Flightless birds Category:Birds of the Altiplano Category:Birds of Patagonia Category:Birds of Argentina Category:Birds of Peru Category:Birds of Chile Category:Birds of Bolivia Darwin's rhea Category:Taxa named by Alcide d'Orbigny