Remove all wood piles and tall grass from around your coops. Piles of anything in addition to feed on the ground for them to forage will draw them in. I never saw a rat here until we thinned a lot of trees, let in sun and pasture grasses and tall weeds took over, things that would not grow under deep shade. Also, we had lots of stuff just shoved under one coop and it was blocked off so the birds could not get underneath. We knew rats were under there because the birds would freak out and peer underneath and we'd seen their silhouettes under there from time to time. When we cleaned it all out and left it open and cut down the tall growth, the rats beat it out into the woods again. But, the point is, don't give them super great places to hide near your coops.
In November, a stray tomcat showed up and stayed and now, the little rodents are running for their lives. He doesn't bother the chickens and cruises under every coop he can get under, striking fear in the hearts of rats and mice everywhere. Good boy, Finn. Will work for cat chow, LOL.