It seems obvious to me that some type of human action is causing this ecological disaster. Bats are such an important natural and FREE form of pesticide that I can't imagine that the governments aren't already all over this trying to find answers and cures. In the long run, farmers and the government would save much more money ensuring the safety and health of all species of bats than it would cost funding the research and solutions. Millions of bats eating 400 insects a night for free and with no effort from humans and no negative ecological cost to the planet, who could possibly ask for a better deal?!