Wow. the ZF7762 is an outdoor AP, correct? If you're losing those, that's an expensive problem.
Yes, monitoring solutions will tell you just when a device dropped off your network so you could run over to the AP location to see what happened after getting an email alert. (I do that w/ workgroup switches)
If these were indoor devices and I suspected that someone was trying to plug them in somewhere else on *my* network, I could conceivably script a solution that would report when the MAC address of a missing AP re-appeared on the network.
For some newer versions of Ruckus firmware, I believe the AP will try to "phone home" to ruckus in the event tha t it doesn't find a controller on the local network. I'm not aware of Ruckus logging information re: what APs tried to "phone home".
I could imagine you configuring your own controller w/ an internet-routable IP address such that you could monitor that IP address for APs trying to contact it from outside your network. That way you could "innoculate" your remaining APs against theft.
If/when you saw an AP trying to reach your controller from outside your network, a packet-cature of that traffic would tell you the source-IP of your stolen AP. (assuming the stolen AP didn't have its configs wiped yet)
That would be quite an involved solution but it's the best I can think of. Let me know if you're interested in hearing more detail on that.