[SoftTalker]

> did the cats eat the chickens and take their place

Maybe not the adults, who are big enough to be a challenge, but almost certainly the chicks.

A friend of mine who lives on a farm was trying to get ducks to live on his pond. He was advised to shoot all the feral cats he could find, which he did. He still has something of a problem with snapping turtles nabbing the ducklings as they swim, but he's working on that too.