Can you guess what it's trying to do??

(No boasting about myself) Wanted to share with this community.Sight of this dog makes me so happy and the way he responds to me.This was the dog I found tied to a tree with a broken bone near my house where I go for a walk I brought it to my home and after 2 months of treatment it's fine and I am on my terrace relaxing for sometime right now and it's trying to catch something on terrace.What do you think it might be??