There is an old timers trick where you raise kittens with baby chicks and they grow up not recognizing them as prey. We do this with many of our cats and as adults they don't even bother going after the chicks. The cats that do not have this upbringing however (we can't catch all the litters all the time), have learned to give our girls a WIDE berth. From a cats perspective,, there is is nothing worse than a very large group of irate birds bearing down on it. Also,, out birds can be better mousers than the cats sometimes as well