get a "trip wire" hooked up to an ecall with a yote howls
lol
or try a cheap walmart kids bow qith rubber blunts
it will scare them quite a bit
also if legal to get blowguns you can get the bigbore blowguns with the steel tipped stun darts they are a "dart" with a round steel tip and sting like heck
they leve a nasty bruise dont ask how i know
oh and they work very well on cats 