A rhea bird is a member of the family Rheidae, a group of large birds native to South America. The family includes two species: the greater rhea bird and the lesser rhea bird. They are flightless, like their relatives, ostriches and emus. They have rounded bodies covered in large feathers, which usually are grayish-brown in color. Their legs are long and powerful, and they have long necks with small heads and pointed beaks.
The greater rhea bird, also known as the Rhea americana, is found in the plains and woodlands of Argentina and Brazil. These birds can be as tall as 4 feet (about 1.2 meters), making them the largest bird in South America. The lesser rhea bird, also called the Rhea pennata or Darwin’s rhea, lives in steppes, scrublands and wetlands in Chile, Argentina, Peru and Bolivia. Standing about 3 feet (0.9 meters) tall, the lesser rhea is smaller than the greater rhea.
Both greater and lesser rheas live in flocks, and they are known to form mixed herds with other herbivores, including deer and guanacos. Males leave the group during mating season to stake out territory. Each male builds a large ground nest in which several females lay eggs. He protects and incubates the eggs of all of his mates for six weeks, until they hatch. He continues to defend the chicks until they are old enough to be self-sufficient.
Rhea birds also are omnivorous. They eat plants, fruits and small lizards, among other things. The rhea bird often feasts on crops, making it a target for angry farmers. This is particularly a problem for the greater rhea, whose habitat typically is near agricultural centers. Some farmers, however, keep rhea birds alongside their grazing herds of sheep because the birds eat the burrs that the farmers would otherwise have to remove from the wool.
These birds commonly are used commercially as well. For example, their meat and eggs are sold for food, and the resilient eggshells are used to create decorative carvings. Likewise, the feathers are used for decoration, and rhea skin is tanned to make leather. Many birds are killed for these valuables, while others are captured and kept as pets or used for egg production.
The rhea population is small and dwindling. Rhea birds commonly are driven out by expanding farmland and hunted by territorial farmers. Their eggs are stolen for food and decoration. Some young birds are tamed, and some are killed for the valuables they produce. These factors combined pose a threat to the rhea bird that conservationists are working hard to address.