The rhea stands about five feet tall, weighs fifty pounds, and has three toes. The male and the female have similar characteristics. The only real difference is that the male is slightly larger than the female. The common rhea has long, soft feathers of grayish or brownish color that droop over the hind part of its body. The long- billed rhea is somewhat like the common rhea except that it is smaller and darker.
Rheas are able to reproduce when they are two or three years old.
Their breeding season is between September and December, earlier in the north than in the south. Rhea eggs are different because they can change color. The males incubate the eggs over a forty-day incubation period. The chicks reach adult size in about half a year. Their meat is not tasty.