Thor was not going to let Loki or his children get the best of him. In fact, hurting Fenrir might draw Loki back out. It was a brute tactic, but it was what a big, Scandinavian god used.
There was no mistaking that awful dog this time. As Thor found himself on the outskirts where less people were likely to be around he called out. "Come on out you mutt! I cab smell you!"