Rhea (bird)
\n| Rheas |
|---|
\n |
\n |
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\n| \n\n |
| Species |
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\n\n Rhea americana
\n Rhea pennata\n |
\n
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Rheas are large flightless
birds native to
South America. \nThe name was given in 1752 by Paul Mohring (his reason for choosing this name, from classical mythology, is not known).
Rheas are polygamous with males courting between two and twelve females. After mating, he builds a nest, in which each female lays her eggs. The male incubates from ten to sixty eggs; the chicks hatch within 36 hours of each other. The females, meanwhile, may move on and mate with other males. While caring for the young, the males will charge at anyone--including humans and female rheas--who approaches the chicks.
Rheas are
omnivorous, preferring broad-leafed plants, but also eating seeds, roots, fruit, insects, and small vertebrates.
American rhea
Rhea americanus (the gray or common rhea) is not only the largest species of rhea, but the largest South American bird, with adults averaging 23 kilograms (51 lb).
Farmers sometimes consider them pests, because they will eat almost any crop plant.\nBecause of this, farmers sometimes kill the birds. This, along with egg gathering and habitat loss, has led to a sharp population decline; the species is listed as being of
special concern.
American rheas live in
grassland,
savanna, scrub
forest,
chaparral, and even
desert, but prefer areas with at least some tall vegetation. During breeding season (which ranges from August to January, depending on location), they stay near water.
Darwin's rhea
Rhea pennatus (Darwin's rhea, syn. R. darwini) is 90 to 100 centimeters (3 ft to 3 ft 4 in) tall, and has larger wings than other ratites, enabling it to run particularly well. They can reach speeds of 60 km/hour, enabling them to outrun predators. The strong claws at the end of each wing are effective weapons.
The males of this species become aggressive once they are incubating eggs. 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.
Outside the breeding season, Darwin's rheas are quite sociable: they live in groups of from 5 to 30 birds, of both sexes and a variety of ages.
Darwin's rhea lives in areas of open scrub in the grasslands of
Patagonia and on the
Andean plateau. It is classified as
endangered throughout its range.
The "lesser rhea" (
Pterocnemia pennata, formerly
R. macrorhyncha) appears to be a synonym for
R. darwini.
