My dog howls at sirens?

my lab does the same thing! I know my dog doesn't do it because he is afraid of them, and I thought for a long time he did it because the pitch of the sirens was so high it hurt his ears. Now I'm starting to think he does it just because he can. Who knows... The only way to really tell if your dog is scared of the noise is if he trembles, or tucks his tail between his legs, or other such behavior. Sounds like from what you described that he's not scared. I guess all we can do is watch our dogs howl at the sirens... (and I laugh too!) Take care and good luck!