How much money can bats save farmers with natural pest control services? That's what Thomas Kunz, a professor at the Center for Ecology and Conservation Biology at Boston University, wants to know.

Each night, more than 100 million free-tailed bats disperse from caves and bridges in south-central Texas to forage for food. They ingest enormous quantities of insects, which include a variety of destructive agricultural pests such as the fall armyworm, cabbage looper, tobacco budworm, corn earworm and cotton bollworm. The magnitude at which these pests can affect crops economically is enormous, but if farmers can determine how bats impact these pests, the number of pesticide applications could be reduced.

"If bats are not protected in Mexico, where they winter, they won't be as effective in consuming agricultural pests here in the U.S.," Morton says. "Education on both sides of the border is essential to maintaining healthy populations of these highly beneficial animals."