Rheidae – Rheas

The Rheas are large (the Greater Rhea is the largest bird in South America weighing c. 25kg and standing up to 1.8m tall) flightless birds that are three toed, terrestrial and have long legs and long necks. They live for about 10 years in the wild. The are confined to South America where they inhabit open grassland, grassy wetlands or scrub ranging from sea-level up to 4500m and even into very arid areas. When not breeding they form flocks of up to 100 birds. They generally eat broadleaf foliage, seeds and fruit but will also take insects, scorpions, reptiles, and small mammals and birds. Often eating seeds and tough vegetation they swallow pebbles which help grind the food and so aid digestion. As they tend not to eat grains they are considered beneficial to farmers as they will take pests from crops including locust, beetles and other pests.

Like other ratites males tend eggs and nests.

The IOC recognises just two species in this family, which are:

Greater Rhea Rhea americana
Lesser Rhea Rhea pennata

The ‘Puna Rhea’ was formerly considered a separate species but recent evidence shows it to be a race of Lesser Rhea.