Rhea refers to a specific type of bird, remember it's not the general term for all birds. In the wildlife sanctuary, they have a separate enclosure for rheas.
Pro Tip 2/3
Not an Ostrich
Don't confuse a rhea with an ostrich; they're similar but different species. I saw a rhea at the zoo, not to be mistaken with the ostriches we saw earlier.
Pro Tip 3/3
Native Habitat
Remember that rheas are native to South America when mentioning their habitat or origin. The rhea we observed was a creature accustomed to the wide open plains of South America.