It breaks my heart to see a red breasted Robin on the lawn, but as a cat owner I take all care responsibility for my cats . On the farm we have 3x cats and they all have their work cut out for them catching rats and mice. I see more fledgling birds taken by the goshawk and the sparrow hawk than I do cats.Some are hunters and some really aren't, I'd think by now you would know if he was the killing type lol. Some people see the constant gifts of native birds on the doorstep as just a normal part of cat ownership which is terrible.