Hello folks. Hilda here is having issues with missing feathers. Any idea what the cause might be? Mites, boredom, another chicken? She's missing feathers around her vent and then over the course of 24 - 48 hours, she was missing strips of feather along each side of her neck. It's been cold, like -15F, and I'm worried about her staying warm without feathers. Thank you for any and all help!