my chickens (all 80 of them) free range round our local area...its just fields and no traffic so a great 'play' area for them. the winter is drawing in fast here and ive been reading here on byc that people dont let their birds free range over winter...why is this? increased threat of predators? shorter days? fear of birds wandering too far? i would like to know do i need to erect a fence to keep them confined around their houses over winter or can they continue to free range?