Aww, I feel for your wife. Losing birds really hurts, especially when you're just starting out. Give her some time to mourn the loss, but encourage her to try again! We have ALL suffered loss for various reasons. I really don't think the blame lies on leaving the coop door open.
When the chickens roam into other people's yards you have no control over what they come into contact with...antifreeze, metal pieces, rat poison, etc. I don't recommend leaving them out unsupervised until you get a real good feel for chickens and what they can get into when you aren't watching. They will definitely eat mice, which is one of the reasons I only use mouse traps to control vermin.
Direct cold wind is not good for birds, but chickens are incredibly well insulated. Feathers are the best insulator in the world! I don't think a few hours of cold wind would kill them the way you described. If chickens aren't comfortable they will move to get to a more comfortable spot. My gut is telling me they ingested something toxic.
I feel so bad for you both. Please do try again. Owning chickens is so rewarding!
When the chickens roam into other people's yards you have no control over what they come into contact with...antifreeze, metal pieces, rat poison, etc. I don't recommend leaving them out unsupervised until you get a real good feel for chickens and what they can get into when you aren't watching. They will definitely eat mice, which is one of the reasons I only use mouse traps to control vermin.
Direct cold wind is not good for birds, but chickens are incredibly well insulated. Feathers are the best insulator in the world! I don't think a few hours of cold wind would kill them the way you described. If chickens aren't comfortable they will move to get to a more comfortable spot. My gut is telling me they ingested something toxic.
I feel so bad for you both. Please do try again. Owning chickens is so rewarding!