We live on a farm. Hawks are rampant in our area. I saw one fly over me so low that I could see he had a fish from the local lake. I also saw one behead one of our chickens! I work with exotic birds and the horror stories come with the job. One of our customers was on his porch with his parrot on his shoulder and a hawk actually swooped him!
So, yea in my opinion a hawk would take a Yorkie.
