This is good advice on removing possible hiding spots and food sources. I do suggest a metal bin would be better than a plastic, because if rats can chew through 2x4s and even concrete, I think they can chew through plastic.
What I suggest, while the flock is away, get some one-bite rat poison...
I would start poisoning the rats right away. In my neighborhood, I have a neighbor who is getting similar complaints. Everyone, including myself, has seen rats in her woods and around her barn, and last year, our neighborhood got overtaken by rats. Our neighbors had a legit reason to complain...