You shouldn't let your Yorkie outside by itself. I had a friend of mine who didn't listen to me and her Yorkie was picked up by a Hawk. She had a wood privacy fence with a nice open green backyard. Thinking it would be the best thing to do with letting her Yorkie outside by itself and not watching for good exercise. It didn't go well at all. She cried to me for several days. She told me she heard her Yorkie screaming as it was picked up and was helpless when the Hawk flew away with her Yorkie.
Just a lesson learn and hopefully others too. Treat your Yorkie just like your child. One eye on him/her and the other around for danger.
