I live in London and have had 4 hens for just over a year. They share a 7 meter square pen but also range freely when I am around to keep an eye out for foxes and strange cats. They went through a bout of feather pecking when I had to keep them penned for 2 months during avian flu restrictions but this reduced when they were allowed out again. I've just returned from a 10 day holiday, during which they were penned again, to find one hen (a copper black) emaciated and badly pecked. She recovered a bit when I put the 2 worst peckers in broody boxes leaving her with one less aggressive companion. But I felt I couldn't keep the two boxed up for more than a couple of days. I tried dividing the pen but the two got back into the roost. This morning the victim was hiding in the roost again and was immediately visciously attacked by the aggressive pair when she came out to feed. What should I do?