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====Variations==== | ====Variations==== | ||
Divided into two non-overlapping subspecies groups sometimes treated as separate species. The two groups are separated by a large area of unsuitable habitat and are believed to have diverged after the rise of the Andes which isolated the two populations. | Divided into two non-overlapping subspecies groups sometimes treated as separate species. The two groups are separated by a large area of unsuitable habitat and are believed to have diverged after the rise of the Andes which isolated the two populations. | ||
− | *'''Darwin's Rhea''': Patagonian steppe. Back and scapular feathers finely tipped white with tips becoming larger lower down on the grey feathers creating a white fringe to the skirt. Has more transverse scutes (scales) on front of leg. | + | *'''Darwin's Rhea''': Patagonian steppe. Back and scapular feathers finely tipped white with tips becoming larger lower down on the grey feathers creating a white fringe to the skirt. Has longer legs and more transverse scutes (scales) on front of leg. |
− | *'''Puna Rhea''': Altiplano grassland. White feather tips mostly near the front edge of the skirt creating a forward white patch at the base of the neck. | + | *'''Puna Rhea''': Altiplano grassland. White feather tips mostly near the front edge of the skirt creating a forward white patch at the base of the neck. Shorter legs and fewer transverse scutes on front of leg. |
==Distribution== | ==Distribution== | ||
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#{{Ref-Clements6thAug18}}#{{Ref-Jaramillo03}}#Lesser Rhea (''Rhea pennata''), In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. retrieved from Neotropical Birds Online: https://neotropical.birds.cornell.edu/Species-Account/nb/species/lesrhe2 | #{{Ref-Clements6thAug18}}#{{Ref-Jaramillo03}}#Lesser Rhea (''Rhea pennata''), In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. retrieved from Neotropical Birds Online: https://neotropical.birds.cornell.edu/Species-Account/nb/species/lesrhe2 | ||
#Folch, A., Christie, D.A., Jutglar, F. & Garcia, E.F.J. (2019). Lesser Rhea (''Rhea pennata''). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/52400 on 18 January 2019). | #Folch, A., Christie, D.A., Jutglar, F. & Garcia, E.F.J. (2019). Lesser Rhea (''Rhea pennata''). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/52400 on 18 January 2019). | ||
+ | #del Hoyo, J., Collar, N. & Garcia, E.F.J. (2019). Puna Rhea (''Rhea tarapacensis''). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/467080 on 18 January 2019) | ||
{{ref}} | {{ref}} | ||
Revision as of 16:28, 18 January 2019
Alternative name: Darwin's Rhea; includes Puna Rhea
- Rhea pennata
Identification
Length: 92½–100 cm. (36½-39¼ in.)
Plumage greyish-brown with whitish underparts. Upperparts are flecked with white white spots which help distinguish it from the larger Greater Rhea. The female is duller with fewer and smaller white spots on the back. Juveniles are browner and lack the white spotting. They generally attain full adult plumage in their first or second year. Young chicks are greyish brown with black stripes.
Variations
Divided into two non-overlapping subspecies groups sometimes treated as separate species. The two groups are separated by a large area of unsuitable habitat and are believed to have diverged after the rise of the Andes which isolated the two populations.
- Darwin's Rhea: Patagonian steppe. Back and scapular feathers finely tipped white with tips becoming larger lower down on the grey feathers creating a white fringe to the skirt. Has longer legs and more transverse scutes (scales) on front of leg.
- Puna Rhea: Altiplano grassland. White feather tips mostly near the front edge of the skirt creating a forward white patch at the base of the neck. Shorter legs and fewer transverse scutes on front of leg.
Distribution
Peru, Bolivia, northern Chile and north-western Argentina, and well separated from the above, in southern Chile and Argentina.
Taxonomy
Pterocnemia vs. Rhea
Some authorities (Howard & Moore, 2003) place Lesser Rhea (R. pennata) in the monotypic genus Pterocnemia. However, Sibley & Monroe (1996), Clements (2007) and SACC since July 2008 place pennata within Rhea and the Opus follows the majority.
Subspecies
This is a polytypic species with three subspecies[1].
- R. p. garleppi - Desert puna of se Peru, sw Bolivia and nw Argentina
- R. p. tarapacensis - Puna of n Chile (Arica to Atacama)
- R. p. pennata - Patagonian steppes of s Argentina and Magellanic Chile
The Lesser Rhea has been proposed split into two species: Puna Rhea (Rhea tarapacensis) with subspecies garleppi, and Darwin's Rhea (Rhea pennata)[2][4].
Habitat
Grass and scrubland, in the north at high elevation, in the south in lowland and foothills.
Behaviour
Rheas are flightless but are adept runners, reaching speeds of up to 60 km/hr.
Breeding
Their mating system is both Polyandry and Polygyny. Males mate with multiple females and females mate with multiple males. The nest is a scrape in the ground, lined with dry grass or twigs. It is built by the male who incubates and cares for young from multiple females. Each nest may contain between 10 and 30 eggs, which start yellowish green but fade to buff over time. The male incubates the eggs and cares for the young. Incubation period is around 40 days. The young are about 90 percent of adult size by 8 to 9 months but may not reach sexual maturity until about three years in males, and two years in females.
Diet
They are omnivorous feeders, taking mostly plant matter including grasses and seeds, but also small animals, especially insects.
Vocalisations
The male makes a low roaring sound during breeding.
Movements
Resident but southern populations move into uplands for breeding.
References
- Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2018. The eBird/Clements checklist of birds of the world: v2018. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
- Jaramillo, A. 2003. Birds of Chile. Princeton & Oxford: Princeton Univ. Press. ISBN 978-0691117409
- Lesser Rhea (Rhea pennata), In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. retrieved from Neotropical Birds Online: https://neotropical.birds.cornell.edu/Species-Account/nb/species/lesrhe2
- Folch, A., Christie, D.A., Jutglar, F. & Garcia, E.F.J. (2019). Lesser Rhea (Rhea pennata). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/52400 on 18 January 2019).
- del Hoyo, J., Collar, N. & Garcia, E.F.J. (2019). Puna Rhea (Rhea tarapacensis). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/467080 on 18 January 2019)
Recommended Citation
- BirdForum Opus contributors. (2024) Lesser Rhea. In: BirdForum, the forum for wild birds and birding. Retrieved 26 April 2024 from https://www.birdforum.net/opus/Lesser_Rhea