The Rhea is a large flightless bird native to South America. American
Rheas live in grassland, savanna, scrub forest, chaparral, and even desert, but prefer areas with at least some tall vegetation. 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 Common Rhea, Rhea americana, is not only the largest species of rhea, but also the largest bird in the Americas. Adults weigh up to 66 pounds. Darwin’s Rhea, Rhea pennata, is 3 to 3.5 feet tall and has larger wings than other ratites, allowing it to run particularly well. They can reach speeds up to 60 km/hour, enabling it to outrun predators. Sharp claws on their toes make for effective weapons.
Rheas are polygamous, with males courting between two and twelve females. After mating, the male 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. Farmers sometimes consider them pests, because they will eat crop plants such as cabbage, chard, and bok choi. Because of this habit, farmers sometimes kill the birds. This, along with egg gathering and habitat loss, has led to a sharp population decline.
Rheas have an incredible immune system that allows injured birds to heal rapidly with little intervention. This is reflected in the commercial uses of the animal. The fat of the birds is used as an anti-inflammatory salve. Use of the meat as an energy supplement is patented in the U.S. and Canada by an American woman who has spent 12 years working to reduce chick mortality and provide a commercial basis for the species, trying to ensure its long-term survival.