Well, yes. You can either buy a coop with an attached, enclosed run or a fox-proof electric fence.
Our cat did try and stalk the hens for fun when we first got them, but never attacked them and he was a decent mouser.
Our cat did try and stalk the hens for fun when we first got them, but never attacked them and he was a decent mouser.
In general, to a cat, "runs away" == "prey" and "comes right up to me" == "equal and/or potential threat"
Partly aggression - chickens are/can be nasty and will attack other animals with sharp beaks. Combine this with the fact that they're flock animals, one cat isn't going up against multiple flying, aggressive, pointy ended foes.