In Southeastern US these ants are agricultural pests. Now that you know that fire ants will eat anything that gets in their way, you must know their enemies. The fire ants only enemies are the bird and the termite. These two countries have two very different climates. South America has less distinct seasons than North America does.
Fire ants live in anthills that go deep into the ground.
Fire ants mate all at one time. I have no idea how they know. They just do. The winged queens and winged male fly out of their nests. They fly up in the air and the male fertilizes the eggs inside the female.