Fun Facts

Rheas are named after the Greek Titan, Rhea, whose name comes from the Ancient Greek word for “ground.” This name likely refers to their flightlessness.

Both rhea species average the same weight, so the primary difference between greater rheas and lesser rheas is that greaters tend to have longer necks and legs, while lessers are more compact. They have been known to hybridize.

Rheas are flightless but use their long wings while running 40 mph (64.4 km/h) to maintain stability and speed. They often run in zigzags, and the wings balance them during tight turns. They also use their wings for courtship displays.

Males and females breed with multiple partners, but males are responsible for incubating eggs and raising chicks, a six- or seven-month process. Males will raise offspring from multiple females, meaning they may care for over 60 chicks at once.

There is a small population of greater rheas in northern Germany that is descended from one male and five females that escaped from a farm in 2000. The most recent survey numbers the birds at 600, and they are starting to affect local farmers. Although they have previously been protected, the German government now allows the hunting of the birds and their eggs to control the population.