As for calling the cops. Yea you can try it but it will likely be ignored. I speak from experience. A few months ago I was commuting home from school on the mup. As I hit a certain spot a few riders passing the other way warned me about a ped throwing rocks at cyclists. So I proceeded with caution and saw the ped in question. He indeed was throwing rocks at cyclists. So, I stopped before I encountered him and called the cops. I got hung up on twice as soon as I mentioned the situation. Another cyclist who actually had been hit with a rock came over to me and he also called the cops. Again same thing, he got hung up on. SO cops dont seem to care about cyclist related incidents unless it involves a crash or something that absolutely cannot be ignored.

Now in regards to the use of an airzound I think your just as likely if not more to get into a fight for using it than for attempting to talk to the salmon.