They nibble on everything from trees and seeds to cereal crops and sweet potatoes.
But it seems they've developed a special taste for tomatoes - pecking their way through 50,000 of them last year.
Farmers in north eastern Spain are complaining that the birds are stopping them from making a living.
Trouble
The birds originally come from South America.
It's thought some of them were brought over to Spain as pets in the 1970s.
Trouble is, their owners didn't like the noise the birds made, and so released them into the wild.
Predator
Their population is thought to have increased from 50 to a whopping 2,200.
There's so many of them because, as they aren't from Spain, the birds have no natural predator (that's another creature which eats them) in the country.
Now Spanish officials are scratching their heads to come up with a way to stop the birds causing more chaos.
Hear story 
Chat about animals
Which bird are you?
