New studies have revealed that spiders are indeed eating bats, and that they're doing it deliberately and maliciously. Not just one type of spider, mind you, but lots of different species are doing this on a regular basis, and it's happening everywhere. Researchers found out that the only place that spiders aren't sucking the life out of bats is Antarctica, and that's probably only because penguins are higher in fat content.
Sam Barnard/Live Science
This picture was taken in Colorado. Colorado. Nowhere is safe.
Most of the time, the bats are ensnared in strategically placed webs, but not always. Some spiders dispense with all that extra effort and may simply crawl into caves and throttle bats while they sleep, as some huntsman spiders and tarantulas have been observed devouring them on forest floors.
Time to get rid of those bats in your attic the natural way.