Gads. There's no way I would keep a cat that couldn't be trusted to give warning before attacking. My brother and his wife have a Russian Blue that is a serious mouser/birder/lizarder- she supports herself, but comes into the house daily to get a commercial fix.

This cat is called Minni, the Grouch. She goes around growling to herself at every thing and event of which she disapproves and of which there are many, from having to go through the pet door to the glimpse of another animal to someone ensconced in her favorite chair.

I will no longer touch her. I had never been bitten by any cat and I have petted and cuddled many a one. One day when I was visiting the Grouch came to me purring and winding herself around my arm. So I petted her. At a certain point she had had enough contact and without ado, she turned her head and sank her teeth into the side of my thumb. When I visit them now and she asks for attention, I tell her: Nope. You blew it. Go somewhere else.

Pluck, my foot.