I'm trying to get a Skarmory with Drill Peck so I've got to breed it. I'm using a female Skarmory, but whatever I pair it with, it won't breed. I've tried with Xatu, Dodrio, Doduo and Fearow, all of them males, of course. It says "Skarmory is interested in Dodrio" and viceversa, but I still get no eggs.

Am I doing something wrong? Or is it just that it takes more time than normal to breed this particular species?