I wonder if you can shed some light on this. Recently whenever I go to feed my hens I find they (I think its the hens) have filled up the hopper with the wood chippings from their coop floor and some feathers. There is food underneath, but it is covered by all the chippings and feathers. Has anyone else seen this sort of behaviour before and can anyone guess what causes it? It is becoming annoying as I have to tip out all the bark and feathers everytime I feed them and I'm wasting food each time. any help with this much appreciated.