Owls DO eat bats.
Though not a main diet staple, birds of prey such as owls and hawks will prey upon bats. Other natural predators to the bat include other bats, snakes, raccoons, weasels, mink, and rodents. Smaller bat species sometime fall prey to fish and bullfrogs.
An interesting predator to the bat is the great horned owl known for its hunting ferocity. The great horned owl will feed on bats, birds, rabbits, skunks, woodchucks, and occasionally domesticated cats. These owls are also known to cache food for later use often incubating it in frozen weather and consuming it once it thaws.
” All About Birds : Great Horned Owls .” Birds, Cornell Lab of Ornithology. N.p., n.d. Web. 15 Nov. 2011. http://www.birds.cornell.edu/AllAboutBirds/owlp/ghowl/document_view
“Adirondack Ecosystem.” SUNY-ESF, SUNY College of Environmental Science and Forestry. N.p., n.d. Web. 15 Nov. 2011. http://www.esf.edu/aec/adks/mammals/littlebrownbat.htm