Arnie, I know of two ways to get rid of rats which do not harm other creatures.

First you find its tunnels. Then you put bags of poison in the tunnels and bury them. Wear clean gloves so as not to leave your scent on the bags. Details like that should be covered in the directions.

Another way it to burn a fusee-type device in the tunnel. This is not for near the house.

I feed the birds, and once every few years we get a rat or two. These two methods have got rid of them.

Thanks for explaining about the skunks, possums, etc.