Francesca : I have another rat themed message! We have been fighting rats here in Oakland CA since we got our chicken coop up about 4 years ago. The only time we saw no rats was when we had to re-home our flock to go on an extended "retirement celebration" vacation last summer. We started up fresh again in September with a dozen 6 week old pullets, two rescued Silkies from a slaughterhouse, and a pair of Mille Fleur bantams. And no surprise, now we have at least that many rats.
We are handling the problem by picking up the feed before locking up the birds at night and that works fairly well - at least that removes temptation for the overnight rat patrol. Trapping and poisoning does not get rid of them so we have decided to try a couple of feral cats - there is a program here in CA called Tenth Life Foundation which places cats in outside homes/barns/yards as rodent hunters. These cats are deemed unacceptable for adoption by the local shelter (failing the personality test, or simply strays which are kind of wild and unlikely to be adopted) and this program thus far has placed over 500 cats with people like us who have a proper set up for them.

The two cats just arrived, and they will be acclimated to their new location in dog crates for 2-3 weeks in our yard until they get used to the place. They are already neutered and innoculated and there is no adoption fee. So we are saving two lives. After they get used to the place, we hope they will "give back" by