Still big enough for raccoons to reach through and also allow smaller predators to get through, like mink, weasels, rats, snakes. You'd still have to reinforce it with hardware cloth.A level up is to use pvc coated chain linm fencing. It costs LOADS but is indestructable.
and Welcome to Backyard Chickens.
to have you here with us. Enjoy your time here at BYC! Good luck with your chick.