Slum, use a little aversive training with a marker ie. while you gas em' with the pepper spray give a loud strong command that will stick in their brains, associating with the trauma they're about to feel as the OC takes affect. The next time you see them out give them the same command and odds are they run for the fort, if not gas them again and repeat. They can take just so much of that stuff. I gassed a rotty many years ago.Took a few seconds to settle in deep but never saw him again after that.
