I recently wathced a NOVA program concerning periodic rat invasions in India which linker bamboo flowering to local crop devistations. The feathred scientist was trying to define the triggers and then to help find solutions.

I recently watched a neighbor install an Invisible Fence to keep his small dog contained. The fence installers apparently set the voltage for a large dog and the wee little dog convulsed when he entered the barrier. It was successfully remedied but electrical barriers stuck with me.

Obviously detection collars on rats are not a solution but a below ground electric charge might create a barrier. This could be a burried wire or perhaps an above ground connection that could release a deterring or fatal shock at the time needed for control. Love to have such be effective for this horrible plague.