For cats, Rosie, it is not. I have been advised so over the years by various veterinarians. The cats over those years who deigned to live with us have been offered only water. They drink very little of it. Perhaps they collect enough of the stuff from the food that they eat - or maybe the few shallow trays we keep topped up in the garden for the use of our avian friends.
[Rosie] Yes they are. In all my time here I have not come across a bundle of feathers in my gardens. Nor has my wife, the gardener of the Dujon Estate. I put down that to the calls some birds make when danger is imminent, particularly from the colloquially named 'Noisy Miner'.
[CdM] Given that most of them there cats lived to seventeen years on average, I have to doubt that supposition. :)