I don't mean to sound flippant, but what if someone did shoot one of these down? Wouldn't that be the best way to solve this? They're not humans so "killing" them shouldn't be a problem. So long as its done over an area with limited chance of them landing on someone where's the downside. I sense there would be zero sympathy for whoever is doing this if their little toy is broken. Let the cops shoot one or two down. They have the firepower.