A bat's natural predators are most commonly snakes and owls. Occasionally parasites and raccoons.
Threats
The bat has threats and maybe this will give you a different view of them. White-Nose Syndrome is a fungus that grows on a bat's nose during the winter when they hibernate in caves. The worst species being effected is the Grey Bat. Another thing that makes things even worse is that bats have small litters of up to 1 pup a year! To make things even more worse, this baby bat doesn't know how to fly and it is about 1/4 of it's mothers weight!
There are about 9 types of bats that are endangered. The rest of the bats have numbers in the millions. If we don't act fast then the bat could go extinct!
A bat contribution
Bats do make a contribution to the world. They are a natural bug repellent, well, not really but, They eat a ton of mosquitoes. So may I recommend getting a bat house in your yard. One single bat can eat 1,000 mosquitoes in an hour!