Our chicken pen suffered it's first attack the other night and I'm happy to say it withstood the assult. We are thinking it was probably a racoon, maybe a opposum. The first picture shows how it tried to dig under the pen, but gave up.
In this picture (if you look closely) you can see how it tried pulling on the chicken wire.
Whatever it was hasn't been back since, but I am sure it will probably try again. I'm thinking a dog may help this situation. We looked into nocturnal watch dogs for the farm and it seems Great Pyrenees tops the list. Any other ideas?