At my work (im a security guard at a gated community) theres a few owls out every night, and I've seen them pick pretty large rabbits up, and attempt to take cats. I'd keep an eye out. Here in AZ, on the news not to long ago, an owl tried to nab someones dog but failed, due to the dog being a bit over weight
Up in Northern MI, I remember a hawk tried to nab my grandmas cat a few times. After a few failed attempts over a weeks time, and it not letting up, something had to be done
It just sat there outside our house in the trees waiting, sneaky little bastard. Beatiful bird though.