When the chicks were younger (9 weeks?), our older cat would "test" them by stalking and showing them he was boss. The last couple weeks, since they were 15-16 weeks at least, the cat has left them alone I think seeing them as too big to contend with. He is a hoot to watch "protect his deck" though... When the chickens come up to check out the fallen BOSS under the wild bird feeder, they occasionally roam around on the deck. When the indoor/outdoor cat is outside, he'll hop on the deck & roll and get all frisky on the edge of the deck steps. He doesn't want any chickens on HIS deck! Comical to watch