Dealing with neighbourhood cats?

[Tmall]

The neighbourhood cats are shitting everywhere on my property. I called animal control and they told me there was nothing I could do unless I know who owns them.

What do I do? I let the dogs chase them out of the yard now, I used to give them shit for it before. The cats keep coming back through the night and shitting in the same spots. I'm at the point where I'm either going to trap them and relocate them, or worse. I am beyond fed up of this. I'm about ready to start collecting my dog shit and throwing it on every cat owner's lawn in the neighbourhood.

I need ideas. Today I made a hot pepper and hot sauce smoothie and poured it where they do most of their pooping. Help me out, because I'm about 3 days away from buying a pellet gun..