My mom would constantly do this with neighborhood cats. They were always under our deck marking so the whole back yard smelled of cat pee. Ugh, disgusting. Plus, it drove our poor dog crazy.Ugh that does sound horrible. I would continue to call animal control every time I see them out. Also, I'm bad like this, and of course it depends on your local shelter, but if you can get a hold of one of them I would pick it up and take it to the local shelter. They will know what it feels like to fear one of their dogs is lost, and then will have to pay to get it out of lock up. And if they don't maybe the dog stands a chance of getting adopted by someone who actually cares about it's well being.