Family Rheas (Rheidae)

Least Concern

Lesser Rhea (Rhea pennata)


French: Nandou de Darwin German: Darwinnandu Spanish: Ñandú petiso
Other common names: Darwin's Rhea

Rhea pennata


, 1834,

lower Río Negro, southern Buenos Aires, Argentina


Previously placed in genus Pterocnemia, on basis mainly of tarsal scutellation and feathered upper tarsus, but genetic studies reveal close relationship with R. americana, and probably more aptly considered congeneric#R#R; has hybridized with R. americana in captivity. Normally considered conspecific with upland R. tarapacensis but#R#R differs in having 16–18 vs. 8–10 tarsal scutes (3), longer legs (allow 2), greyer upperparts (1) and less dense white spots near front edge of “skirt” (1); appears also to intergrade or to be parapatric with R. pennata in Mendoza province, Argentina (possible score 2 or 3), but on other hand plumage variable with age and breeding condition#R; more research needed. Monotypic.

What do (1) and (2) mean? Learn more about the scoring system.

S Chile and WC to S Argentina (S Mendoza S to Strait of Magellan).

Introduced to N Tierra del Fuego.

Descriptive notes

92·5–100 cm; 15–25 kg. Feathering covers thighs and top of tarsi (in front). Male has head, neck and upperparts buffish-brown, lower throat and foreneck... read more


Low roaring sound by male during breeding.


Occupies shrub-steppe and grassland of floodplains, from sea-level to 2000 m; normally breeds in... read more

Food and feeding

Omnivorous. Mainly consumes plant matter, including seeds and grasses; also small animals, especially insects. Normally walks... read more


Season Sept–Jan in N, from Jul in Río Negro (Argentina) and Nov in extreme S. Males simultaneously polygynous, females... read more


Sedentary, but S populations mostly move into uplands for breeding.  

Status and conservation

Not globally threatened. Currently considered of Least Concern. CITES II. Still fairly common, perhaps owing to inaccessibility and bleak conditions which prevail... read more

Recommended citation

Folch, A., Christie, D.A., Jutglar, F. & Garcia, E.F.J. (2018). 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 on 18 March 2018).