That's exactly what I have been doing is moving them inside at night. And the pen is made with chicken wire so a snake can fit through the holes and several black snakes have and we just capture and relocate them several miles away.
I have to had to hens about 2 years old and 6 hens about 3 months old. Only the two older hens were laying at best 2 eggs a day and they were left alone. However the firth morning I came out to check them there was only one dead looked like it had been swallowed up to the shoulders and spit out...