I had a ferret and a bird together. Yes ferrets will go after the bird. They are sneaky like a cat. However they cant pounce or jump high or go fast like a cat. Ferrets are pretty cool too. A ferret also goes into a cage unlike a cat that is free to roam all the time. In fact I had a ferret, bird, cat, dog/ collie in one small apt. They got along. I feel as long as there is supervision you will be fine.