The rheas belong to the category of ratites under the type rhea, and originate from Southern America. They are usually flightless birds. There are two known existing species, which are the American Rhea and the Darwin’s Rhea. The American rhea is known to be the largest species of the genus Rhea. It is also the only known largest American bird alive.

The rhea Americana is known for its reproductive habits. It is large, does not fly and has grey to brown feathers. In addition, it has long legs and long necks, almost similar to an ostrich. They have huge wings, and because it is a bird that cannot fly, the wings are stretched when it runs to act like propellers. A difference with most other birds is that there are three toes on the American Rhea’s feet. Another characteristic feature of the American Rhea is that they store urine in a separate expansion of the cloaca.

Rheas tend to be silent birds, except for the chicks, or when the male is seeking to mate. Outside the breeding season, they usually tend to form flocks of from ten to one hundred birds, particularly for the American rhea. For the other species of rheas, they may form smaller flocks. They basically move in a zigzag manner particularly when they are in danger, using one wing after another in a repeated pattern, just as a rudder. The flocks are known to break up during the season of breeding.

The American Rheas are known to be omnivorous and they eat leafy plants. They also do eat grasshoppers, roots, seeds, fruit, beetles, lizards, and decomposed flesh of dead animals. The American Rhea is polygamous, and males court from between two to tens of hens. Following copulation, the male constructs a shelter in which every hen will lay eggs. The nest is made up of simply prepared ground laced with leaves and grass. The male is known to incubate from ten to sixty eggs, and it places some eggs outside the nest as a way to prevent predators from entering the nest. It is not uncommon for the male to use another male to incubate the eggs while he goes in search of another group of females to start another nest.

The chicks hatch within a space of thirty six hours. That is, after one chick hatches, the next would do so after thirty six hours. Meanwhile, the females may move on and mate with other males. While looking after the chicks, the males are known to be very aggressive, and they can attack any menace approaching the chicks. Even the hen rheas are considered a menace, including human beings.

A young American rhea reaches adulthood in about six months, but they are unable to breed until they attain two years. The Rhea Americana have loads of uses in Southern America. Their fluff is used for making dusters, their skins used for fabricating loose garments, while its meat is used as a staple food to many people.